(slightly shorter for black-hole ULXs). But if the front fails to reach the
outer disc edge, the peak outburst luminosity is given by Eq. (123) with
$R_{\rm out}$ replaced by $R_{\rm tr,max}\leq R_{\rm out}$, where $R_{\rm
tr,max}$ is the maximum radius reached by the instability–triggering heating
front. In this case, the peak luminosity can be up to 50 times larger [142].
This means that wide binaries in which the mass transfer is sub-Eddington
might become transient ULXs at, and close to, the maximum outburst luminosity
if their discs are unstable.

Hameury and Lasota [142] derived analytical formulae describing typical X-ray
transient light curves with great accuracy. They apply also to transient ULXs.
When the heating front brings the whole disc to a hot state ($R_{\rm
tr,max}\approx R_{\rm out}$), the $\dot{M}(t)$ relation during the decay from
outburst maximum is very well described by [378]171717The corresponding
formula in the original publication contains a misprint.

$\dot{M}=\dot{M}_{\rm max}\left[1+\frac{t}{t_{0}}\right]^{-10/3},$ (126)

where the integration constant $t_{0}$ is given by:

$t_{0}=3.19\alpha_{\rm 0.2}^{-4/5}M_{1}^{1/4}R_{12}^{5/4}\dot{M}_{\rm
max,19}^{-3/10}\;\rm yr,$ (127)

with $\dot{M}_{\rm max,19}=\dot{M}_{\rm max}/10^{19}$ g s-1. Here $t_{0}$ is
not the characteristic timescale of disc evolution, which is instead

$\tau=\frac{M_{d}}{\dot{M}}=0.81\psi f^{-0.3}M_{1}^{0.37}f_{\rm
irr}^{0.15}R_{12}^{0.62}\alpha_{0.2}^{-0.8}\;\rm yr,$ (128)

where $M_{d}$ is the disc mass and $f=\dot{M}_{\rm max}/\dot{M}_{\rm
crit}^{+}(r_{\rm out})>1$ [for the derivation see 142]. One can then relate
the maximum outburst accretion rate to the characteristic decay time.

$\dot{M}_{\rm max}=2.0\times
10^{19}\alpha_{0.2}^{2.71}f^{2.02}M_{1}^{-1.65}\left(\frac{\tau}{1\;\rm
yr}\right)^{3.39}f_{\rm irr}^{-1.01}\;\rm g\,s^{-1},$ (129)

Then when both $\dot{M}_{\rm max}$ and $\tau$ are known from observations,
this relation determines $f$, and hence $\dot{M}_{\rm crit}^{+}$ and the size
of the accretion disc.

This phase of the outburst corresponds to a viscous decay, during which X–ray
irradiation prevents the formation and propagation of a cooling front. This
ends when the decreasing accretion rate falls to the critical value
$\dot{M}_{\rm crit}^{+}$ and the front starts propagating into the disc.

If the heating front is unable to reach the outer regions – which happens
quite often in huge discs – the viscous decay phase is missing and, from the
start, the decay-from-maximum $\dot{M}(t)$ relation corresponds to the
cooling–front propagation, and has the form

$\dot{M}=1.31\times 10^{17}\alpha_{0.2}^{2.71}M_{1}^{-1.65}f_{\rm
irr}^{-1}\left[{\xi}\frac{(t_{0}^{\prime}-t)}{1\;\rm yr}\right]^{3.39}\;\rm
g\,s^{-1},$ (130)

where $t_{0}^{\prime}$ is a constant that is determined by the condition that,
when the cooling front starts, $\dot{M}$ is equal to $\dot{M}_{\rm crit}^{+}$
at the maximum transition radius. Then $t_{0}^{\prime}$ can be written as:

$t_{0}^{\prime}=4.64\;\xi^{-1}M_{1}^{0.37}f_{\rm
irr}^{0.15}\alpha_{0.2}^{-0.8}r_{12}^{0.62}\;\rm yr,$ (131)

and $\xi$ is a constant to be calibrated by numerical simulations; it is found
to be in the range $2.47<\xi\lesssim 8.0$. Here $t_{0}^{\prime}$ is equal to
the duration of this phase of the outburst, and can be directly compared to
observations. As before, there exists a relation between $\dot{M}_{\rm max}$
and ${t_{0}^{\prime}}$:

$\dot{M}_{\rm max}=3.1\times
10^{19}\alpha_{0.2}^{2.71}M_{1}^{-1.65}\left(\frac{\xi}{5}\frac{t_{0}^{\prime}}{1\;\rm
yr}\right)^{3.39}f_{\rm irr}^{-1.01}\;\rm g\,s^{-1},$ (132)

which is essentially the same as in Eq. (129), with $f=1$.

It is important to realise that, for super-Eddington accretion rates,
$\dot{M}(t)$ does not directly represent the observed $L_{X}(t)$ light curve,
as the relation between the luminosity and accretion rate is no longer linear.
Then when considering an outburst whose apparent luminosity is larger than
$\,L_{\rm Edd}$ Hameury and Lasota [142] use the following relations

$\displaystyle L_{\rm x}$
$\displaystyle=(1+\ln\dot{m})\left[1+\frac{\dot{m}^{2}}{\tilde{b}}\right]L_{\rm
Edd}\;\ \ \ \ \ \ {\rm if}\;\dot{m}\geq 1$ $\displaystyle=\dot{m}\,L_{\rm
Edd}\;\hskip 85.35826pt{\rm if}\;\dot{m}<1,$ (133)

where $b=(1+\dot{m}^{2}/\tilde{b})^{-1}$ is a beaming term; the larger the
beaming parameter $\tilde{b}$, the larger $b$ and hence the smaller the
beaming effect. Eq. (55) corresponds to $b=\tilde{b}/\dot{m}^{2}$ with
$\tilde{b}=73$. Since the beaming factor $\tilde{b}/\dot{m}^{2}$ applies only
for $\dot{m}>\sqrt{\tilde{b}}$, in time-dependent calculations, one replaces
it by $(1+\dot{m}^{2}/\tilde{b})^{-1}$ in order to get a smooth transition
with the case where beaming is negligible.

Further, when $\dot{m}\gg 1$ so that the apparent luminosity scales
approximately as $\dot{m}^{2}$, the decay time of the luminosity $\tau_{\rm
L}$ is one half of the decay time of the accretion rate, and Eq. (129) has to
be written as:

$\dot{m}_{\rm
max}=132\,\alpha_{0.2}^{2.71}f^{2.02}M_{1}^{-2.65}\left(\frac{\tau_{\rm
L}}{1\;\rm yr}\right)^{3.39}f_{\rm irr}^{-1.01}.$ (134)

If not all of the disc reaches the hot state, the total outburst duration is
related to the maximum mass accretion rate via Eq. (132), and we must have:

$\dot{m}_{\rm
max}=24.0\,\alpha_{0.2}^{2.71}M_{1}^{-2.65}\left(\frac{\xi}{5}\frac{t_{0}^{\prime}}{1\;\rm
yr}\right)^{3.39}f_{\rm irr}^{-1.01},$ (135)

where $t_{0}^{\prime}$ now refers to the outburst duration.

Figure 19: Observed flux from M51 XT-1 as compared with model predictions for
a 1.4 M⊙ neutron star (red curve) and a 10 M⊙ black hole (green curve). Black
points correspond to SWIFT data and blue points to Chandra or XMM-Newton
observations [courtesy M. Brightman, see also 42].

####  3.16.1 M51 XT-1

M51 XT-1 is currently the only ULX transient source whose light curve is
suitable for comparison with the prediction of the disc–instability model.
Figure 19 shows how observational data of M51 XT-1 [42] compare with the
predictions of the disc–instability model when the light curve comes from Eqs.
126 and 130, combined with Eq. (133) with the beaming parameter
$\tilde{b}=73$. Two cases are shown. A 1.4 M⊙ accreting neutron star with a
disc size $4.8\times 10^{11}$ cm; and a 10 M⊙ accreting black hole, with a
disc extending to $4.9\times 10^{11}$ cm. As can be seen, the agreement is
reasonably good, and as acceptable as the original fit with a power law with
index $-5/3$ [42]. These data can also be fitted with a 10 M⊙ accreting black
hole, with a disc extending to $4.9\times 10^{11}$ cm.

In the neutron star case, the maximum accretion rate is $6\times 10^{19}$ g
s-1, while in the black hole case it is $1.5\times 10^{20}$ g s-1. Hence the
emission from a black-hole system would not be beamed, but for a neutron-star
accretor the beaming factor would be $b=0.06$, as expected for $\dot{m}=33$.
The mass transfer rate can be very roughly estimated to be of order 1 – 2% of
the maximum accretion rate, i.e. $1-3\times 10^{18}$ g s-1.

Hameury and Lasota [142] showed that taking $\tilde{b}=200$ instead of
$\tilde{b}=73$ in Eq. (133) also provides an acceptable fit, but
$\tilde{b}=20$ is excluded by the Chandra and XMM-Newton points, thus
suggesting only moderate beaming.

####  3.16.2 HLX-1 in ESO 243-49

HLX-1 in the galaxy ESO 243-49 [108] attracted a lot of attention as the best
IMBH candidate among ULXs. It is the brightest ULX candidate known; its
luminosity is variable and can exceed $10^{42}$ erg s-1 at maximum. Its
association with the galaxy ESO 243-49 at a distance of 95 Mpc is fairly well
established [492, 410] so there is little doubt about its luminosity [see,
however, 237]. Greene et al. [133] conclude that a self-consistent scenario is
that HLX-1 is a central massive black hole on the low–mass end of the mass
distribution of nucleated $10^{9}-10^{10}\rm\,M_{\odot}$ galaxies. Its small
host galaxy was accreted and tidally stripped by ESO 243-49, leaving only the
bare nuclear star cluster near the black hole (e.g., Mapelli et al. 260). Star
formation, perhaps encouraged by the merger, could have increased the capture
rate for the hole to acquire a companion star on which it is currently
feeding. Then by the definition adopted in this review HLX-1 is not an IMBH
candidate, but was the central MBH of a small galaxy, which (unusually) has
been accreted and disrupted by a larger one.

In line with this picture, HLX-1’s historical light curve (see e.g. Godet et
al. 131) initially showed a promising series of almost annual outbursts, only
to lose this quasi–periodicity later on. Subsequent to its discovery, a number
of so–called QPE (‘quasiperiodic eruption’) sources have recently been found
from the centres of small galaxies (e.g. Miniutti et al. 300, 299, Arcodia et
al. 15). These can be modelled as tidal disruption near–misses (King 186):
instead of being fully disrupted by filling its tidal radius near the MBH (a
tidal disruption event or TDE) an infalling star fills its tidal lobe only at
the pericentre of a very eccentric orbit about the MBH. In the small galaxy
GSN 069 the star is probably a low–mass white dwarf (King 186), and the
predicted CNO anomaly was later found (Sheng et al. 404). It appears that this
model works well for all the currently recognised QPE systems [187]. These
systems all have very short lifetimes as the orbits shrink under gravitational
radiation, which is what drives the mass transfer.

Modelling HLX-1 instead as a transient IMBH source undergoing disc outbursts
shows that the outburst timescales are incompatible with a central mass of
$\gtrsim 10^{4}\,\rm\,M_{\odot}$, as would be required to explain the peak
luminosity of $10^{41}\,{\rm erg\,s^{-1}}$ (Hameury and Lasota 142 and
references therein).

###  3.17 Beaming or not?

The arguments in favour of luminosity beaming in PULXs presented above are
simple and fundamental. The main one is that the observed X-ray luminosities
of magnetic ULXs lie between 6 and 500 $\,L_{\rm Edd}$, with the classic (non
BeX) systems having $L_{X}>20L_{\rm Edd}$. Even if mass is supplied at a
super–Eddington rate, the luminosity is only $L\approx\,L_{\rm
Edd}(1+\ln\dot{m})$, so even $\dot{m}\approx 1000\,(>10^{-5}\rm\,M_{\odot}{\rm
yr}^{-1})$ produces only $\sim 8\,L_{\rm Edd}$.

Explaining these huge excess luminosities by appealing to super–strong
magnetic fields appears unpromising. We have argued above that the presence of
magnetars in PULXs is extremely unlikely. Among other problems, it requires a
cosmic conspiracy confining magnetars to just these binary systems. Be–PULXs
spend most of the time as standard pulsed X–ray sources, and clearly do not
have magnetar–strength fields. Assertions that the “apparent luminosity [of
PULXs] is close to the actual one” [313] are rather surprising, especially
when it is not explained how this is supposed to be achieved.

Mushtukov et al. [313] refer to a table in King and Lasota [190] to claim that
these authors require $a=1/b\sim 20$ for M82 ULX-2, NGC 7793 P13 and NGC 300
ULX1 and $\sim 100$ for NGC 5. But Table 3 shows that the values of $1/b$ for
the first three sources are respectively 17, 6, 6, to which one can add 10 for
ULX-7 in M51.

###  3.18 Measuring mass transfer via the orbital period derivative?

The most important parameter in understanding ULXs, as in any accreting
system, is the instantaneous mass transfer rate $-\dot{M}_{2}$ in the host
binary system. Unfortunately, precisely because we do not yet have a clear
picture of how exactly the mass transfer rate specifies the luminosity of
ULXs, it is difficult to measure $-\dot{M}_{2}$ directly from observation. But
if we assume conservative mass transfer (i.e. conserving both total mass and
angular momentum) we see from Section (3.11) that all quantities such as the
companion mass $M_{2}$, the binary separation $a$, and by Kepler’s law, the
binary period $P\propto a^{3/2}$, evolve on the mass transfer timescale
$M_{2}/(-\dot{M}_{2})$ – see Eq. (104). This makes it tempting to use the much
more easily measured orbital period derivative $\dot{P}$ to estimate
$-\dot{M}_{2}$. The recent papers by Bachetti et al. [21, 22] try to use this
method for the ULX M82 X-2.

As we noted above, the problem of measuring $-\dot{M}_{2}$ is common to all
interacting binary systems, not simply ULXs. There is a long history of
efforts to find $-\dot{M}_{2}$ by using $\dot{P}$ and assuming conservative
evolution, going back at least to early studies of cataclysmic variables
(where a low–mass main–sequence star transfers mass to a white dwarf in a very
circular orbit). But all these attempts give uniformly disappointing results –
not least because even the sign of $\dot{P}$ often flatly contradicts that
expected from conservative evolution. The underlying reason for these
difficulties is that relations like (104) hold only if the quantities
$\dot{P},-\dot{M}_{2}$ are averages over a timescale long compared with the
time $t_{H}$ for the Roche lobe to move one scaleheight within the donor star.
This requirement arises because stars have smooth density distributions rather
than sharp edges. On timescales shorter than $t_{H}$ the instantaneous value
of $\dot{P}$ is always in practice dominated by large but short–term effects,
with varying signs often in conflict with the long–term rate. This point has
been made repeatedly in the literature, going back at least to Pringle [364];
see also e.g. Ritter [377] and Frank et al. 117 (Section 4.4). Pringle (1975)
concluded that “… an accurate estimate of the rate of mass transfer cannot be
deduced from a change of binary period”.

In response to Bachetti et al. [21], King and Lasota [191] estimated
$t_{H}\sim 1000\,{\rm yr}$ for M82 X-2. Then observations of $\dot{P}$ over
humanly accessible timescales cannot give information about $-\dot{M}_{2}$.
King and Lasota [191] further pointed out that direct application of the
method of Bachetti et al. [21] to three well–studied X–ray transients with
known values of $\dot{P}$ (Nova Muscae 1991, XTE J1118+480, A0620–00, see
González Hernández et al. 132 and references therein) was possible, but not
encouraging. These Roche–lobe filling systems are all currently in the faint
quiescent state. Under the assumption of conservative evolution, their values
of $\dot{P}$ would instead predict that all three of them should currently
have high mass transfer rates. Their accretion discs should therefore be
steady rather than transient, putting them stably in bright states – indeed
Nova Muscae 1991 would actually be a ULX. The subsequent publication [22] does
not answer these points.

##  4 Conclusions

Table 7 summarises how various models of ULX behaviour compare with
observations. The case for disc–wind beaming appears fairly strong, and is so
far compatible with a large body of data. Given that the photon–bubble model
does not appear promising, this is the only model which can straightforwardly
apply to both black–hole and neutron–star accretors.

Other models come into consideration if we allow for the idea that ULXs might
not be a single homogenous population, but instead consist of various
different types of systems (as in the example of long and short gamma–ray
bursts). IMBH clearly cannot account for PULXs or Be–star ULXs, and have not
been widely tested in other aspects. Unless their masses are $>3\times
10^{4}\rm\,M_{\odot}$ they cannot account for the striking universal $L_{\rm
soft}\propto T^{-4}$ behaviour of ULX soft X–ray components with luminosities
$>3\times 10^{39}\,{\rm erg\,s^{-1}}$.

Table 7: Models of ULXs model |  blackbody $L\propto T^{-4}$ | winds & nebulae | evolution | luminosity fn | $L>3\times 10^{40}\,\,\mathrm{erg}\,\mathrm{s}^{-1}$ | pulsing | BeX | BH & NS
---|---|---|---|---|---|---|---|---
disc-wind beaming | yes | yes | yes | yes | yes | yes | yes | yes
magnetic beaming | no | ? | yes | ? | yes | yes | no | no
IMBH |  needs $M>3\times 10^{4}\rm\,M_{\odot}$ | ? | ? | ? | yes | no | no | no
magnetars | no | no | fieldstrength? | no | no | yes | no | no
photon bubble | no | no | ? | ? | no | no | no | yes
oriented jets | ? | ? | ? | ? | no | ? | no | ?

Observations of Be – X–ray binaries pose a particular problem for models
invoking magnetic beaming, as they make regular transitions between normal Be
X–ray binary states to PULXs, and back again, when their mass supply rates are
increased or decreased by Kozai–Lidov cycles. None of the Be–star ULXs is
observationally distinct from other Be X–ray systems when it is in its usual
Be X–ray binary state, and in the ULX state these systems have all the same
properties as other PULXs, including a markedly more rapid spin up rate (cf
Fig 13. None of the Be X–ray binaries appears to have a very strong magnetic
field. This makes it inescapable that very strong dipole magnetic fields are
not required for making a PULX. Highly–magnetic PULXs might then at most
constitute some fraction of the PULX population, but there is so far no
clinching demonstration that any PULX contains a neutron star with this kind
of field. Even then there remains the difficulty that this model requires us
to believe that strong–field neutron stars in binaries are unobservable unless
the companion star supplies them with mass at a super–Eddington rate.

Acknowledgments

JPL was supported by a grant from the French Space Agency CNES. MM thanks G.
Israel, S. Carpano, M. Bachetti, F. Fuerst, S. Tsygankov, R. Sathyaprakash and
G. Rodriguez for providing the data for Figure 7.

##  Appendix A “Standard” X-ray pulsars

To illustrate the fact that PULXs differ from standard X-ray pulsars not only
in luminosity $>10^{39}\,{\rm erg\,s}^{-1}$, but also in their very large
spin-up rates $\dot{\nu}>10^{-10}\,{\rm s}^{-2}$, we used the XRP sample with
known luminosities and spin-up rates (Table 8) as compiled by Ziolkowski
[505].

Table 8: Observed properties of ‘classical’ X-ray pulsars Name |  $L_{X}(\rm max)$ [erg s-1] |  $P_{s}$ [s] |  $\dot{\nu}$ [s-2]
---|---|---|---
SMC X-1 | $5.0\times 10^{38}$ | 0.71 | $2.6\times 10^{-11}$
Cen X-3 | $5.0\times 10^{37}$ | 4.84 | $1.9\times 10^{-12}$
GX 1+4 | $4.0\times 10^{37}$ | 122 | $5.2\times 10^{-12}$
4U 0115+63 | $3.4\times 10^{37}$ | 3.61 | $2.2\times 10^{-12}$
A 0535+26 | $1.0\times 10^{37}$ | 104 | $3.0\times 10^{-12}$
Her X-1 | $1.0\times 10^{37}$ | 1.24 | $8.5\times 10^{-14}$
Vela X-1 | $1.5\times 10^{36}$ | 283 | $5.6\times 10^{-13}$
GX 301-2 | $1.0\times 10^{36}$ | 696 | $3.8\times 10^{-13}$
X-Per | $3.9\times 10^{33}$ | 835 | $6.4\times 10^{-15}$

## References

  * Abarca et al. [2018] Abarca, D., Kluźniak, W., Sa̧dowski, A., Sep. 2018. Radiative GRMHD simulations of accretion and outflow in non-magnetized neutron stars and ultraluminous X-ray sources. MNRAS 479, 3936–3951.
  * Abarca et al. [2021] Abarca, D., Parfrey, K., Kluźniak, W., Jul. 2021. Beamed emission from a neutron-star ULX in a GRRMHD simulation. arXiv e-prints, arXiv:2107.01149.
  * Abbott et al. [2016] Abbott, B. P., Abbott, R., Abbott, T. D., Abernathy, M. R., Acernese, F., Ackley, K., Adams, C., Adams, T., Addesso, P., Adhikari, R. X., et al., Feb. 2016. Astrophysical Implications of the Binary Black-hole Merger GW150914. ApJL 818, L22.
  * Abbott et al. [2020] Abbott, R., Abbott, T. D., Abraham, S., Acernese, F., Ackley, K., Adams, e., Oct. 2020. GWTC-2: Compact Binary Coalescences Observed by LIGO and Virgo During the First Half of the Third Observing Run. arXiv e-prints, arXiv:2010.14527.
  * Abolmasov et al. [2007a] Abolmasov, P., Fabrika, S., Sholukhova, O., Afanasiev, V., Mar. 2007a. Spectroscopy of optical counterparts of ultraluminous X-ray sources. Astrophysical Bulletin 62 (1), 36–51.
  * Abolmasov et al. [2008] Abolmasov, P., Fabrika, S., Sholukhova, O., Kotani, T., Sep. 2008. Optical Spectroscopy of the ULX-Associated Nebula MF16. arXiv e-prints, arXiv:0809.0409.
  * Abolmasov et al. [2007b] Abolmasov, P. K., Swartz, D. A., Fabrika, S., Ghosh, K. K., Sholukhova, O., Tennant, A. F., Oct. 2007b. Optical Spectroscopy of the Environment of a ULX in NGC 7331. ApJ 668 (1), 124–129.
  * Abramowicz et al. [1978] Abramowicz, M., Jaroszynski, M., Sikora, M., Feb. 1978. Relativistic, accreting disks. A&A 63, 221–224.
  * Abramowicz et al. [1988] Abramowicz, M. A., Czerny, B., Lasota, J. P., Szuszkiewicz, E., Sep. 1988\. Slim accretion disks. ApJ 332, 646–658.
  * Agrawal and Nandi [2015] Agrawal, V. K., Nandi, A., Feb. 2015. Discovery of a quasi-periodic oscillation in the ultraluminous X-ray source IC 342 X-1: XMM-Newton results. MNRAS 446 (4), 3926–3931.
  * Alston et al. [2021] Alston, W. N., Pinto, C., Barret, D., D’Aì, A., Del Santo, M., Earnshaw, H., Fabian, A. C., Fuerst, F., Kara, E., Kosec, P., Middleton, M. J., Parker, M. L., Pintore, F., Robba, A., Roberts, T. P., Sathyaprakash, R., Walton, D., Ambrosi, E., Aug. 2021. Quasi-periodic dipping in the ultraluminous X-ray source, NGC 247 ULX-1. MNRAS 505 (3), 3722–3729.
  * Andersen and Ransom [2018] Andersen, B. C., Ransom, S. M., Aug. 2018. A Fourier Domain “Jerk” Search for Binary Pulsars. ApJL 863 (1), L13.
  * Anderson and Itoh [1975] Anderson, P. W., Itoh, N., Jul. 1975. Pulsar glitches and restlessness as a hard superfluidity phenomenon. Nature 256 (5512), 25–27.
  * Archibald et al. [2016] Archibald, R. F., Kaspi, V. M., Tendulkar, S. P., Scholz, P., Sep. 2016\. A Magnetar-like Outburst from a High-B Radio Pulsar. ApJL 829 (1), L21.
  * Arcodia et al. [2021] Arcodia, R., Merloni, A., Nandra, K., Buchner, J., Salvato, M., Pasham, D., Remillard, R., Comparat, J., Lamer, G., Ponti, G., Malyali, A., Wolf, J., Arzoumanian, Z., Bogensberger, D., Buckley, D. A. H., Gendreau, K., Gromadzki, M., Kara, E., Krumpe, M., Markwardt, C., Ramos-Ceja, M. E., Rau, A., Schramm, M., Schwope, A., Apr. 2021. X-ray quasi-periodic eruptions from two previously quiescent galaxies. Nature 592 (7856), 704–707.
  * Arévalo and Uttley [2006] Arévalo, P., Uttley, P., Apr. 2006. Investigating a fluctuating-accretion model for the spectral-timing properties of accreting black hole systems. MNRAS 367 (2), 801–814.
  * Arnaud et al. [1999] Arnaud, K., Dorman, B., Gordon, C., Oct. 1999. XSPEC: An X-ray spectral fitting package.
  * Asvarov [2014] Asvarov, A. I., Jan. 2014. Size distribution of supernova remnants and the interstellar medium: the case of M 33. A&A 561, A70.
  * Atapin et al. [2019] Atapin, K., Fabrika, S., Caballero-García, M. D., Jun. 2019. Ultraluminous X-ray sources with flat-topped noise and QPO. MNRAS 486 (2), 2766–2779.
  * Bachetti et al. [2014] Bachetti, M., Harrison, F. A., Walton, D. J., Grefenstette, B. W., Chakrabarty, D., Fürst, F., Barret, D., Beloborodov, A., Boggs, S. E., Christensen, F. E., Craig, W. W., Fabian, A. C., Hailey, C. J., Hornschemeier, A., Kaspi, V., Kulkarni, S. R., Maccarone, T., Miller, J. M., Rana, V., Stern, D., Tendulkar, S. P., Tomsick, J., Webb, N. A., Zhang, W. W., Oct. 2014. An ultraluminous X-ray source powered by an accreting neutron star. Nature 514, 202–204.
  * Bachetti et al. [2021a] Bachetti, M., Heida, M., Maccarone, T., Huppenkothen, D., Israel, G. L., Barret, D., Brightman, M., Brumback, M., Earnshaw, H. P., Forster, K., Fürst, F., Grefenstette, B. W., Harrison, F. A., Jaodand, A. D., Madsen, K. K., Middleton, M., Pike, S. N., Pilia, M., Poutanen, J., Stern, D., Tomsick, J. A., Walton, D. J., Webb, N., Wilms, J., Dec. 2021a. Orbital decay in M82 X-2. arXiv e-prints, arXiv:2112.00339.
  * Bachetti et al. [2021b] Bachetti, M., Heida, M., Maccarone, T., Huppenkothen, D., Israel, G. L., Barret, D., Brightman, M., Brumback, M., Earnshaw, H. P., Forster, K., Fürst, F., Grefenstette, B. W., Harrison, F. A., Jaodand, A. D., Madsen, K. K., Middleton, M., Pike, S. N., Pilia, M., Poutanen, J., Stern, D., Tomsick, J. A., Walton, D. J., Webb, N., Wilms, J., Dec. 2021b. Orbital decay in M82 X-2. arXiv e-prints, arXiv:2112.00339v2.
  * Bachetti et al. [2020] Bachetti, M., Maccarone, T. J., Brightman, M., Brumback, M. C., Fürst, F., Harrison, F. A., Heida, M., Israel, G. L., Middleton, M. J., Tomsick, J. A., Webb, N. A., Walton, D. J., Mar. 2020\. All at Once: Transient Pulsations, Spin-down, and a Glitch from the Pulsating Ultraluminous X-Ray Source M82 X-2. ApJ 891 (1), 44.
  * Bachetti et al. [2013] Bachetti, M., Rana, V., Walton, D. J., Barret, D., Harrison, F. A., Boggs, S. E., Christensen, F. E., Craig, W. W., Fabian, A. C., Fürst, F., Grefenstette, B. W., Hailey, C. J., Hornschemeier, A., Madsen, K. K., Miller, J. M., Ptak, A. F., Stern, D., Webb, N. A., Zhang, W. W., Dec. 2013. The Ultraluminous X-Ray Sources NGC 1313 X-1 and X-2: A Broadband Study with NuSTAR and XMM-Newton. ApJ 778 (2), 163.
  * Baldassare et al. [2020] Baldassare, V. F., Dickey, C., Geha, M., Reines, A. E., Jul. 2020. Populating the Low-mass End of the MBH-$\sigma$ Relation. ApJL 898 (1), L3.
  * Basko and Sunyaev [1976] Basko, M. M., Sunyaev, R. A., May 1976. The limiting luminosity of accreting neutron stars with magnetic fields. MNRAS 175, 395–417.
  * Begelman [2002] Begelman, M. C., Apr. 2002. Super-Eddington Fluxes from Thin Accretion Disks? ApJL 568, L97–L100.
  * Begelman et al. [2006] Begelman, M. C., King, A. R., Pringle, J. E., Jul. 2006. The nature of SS433 and the ultraluminous X-ray sources. MNRAS 370, 399–404.
  * Belczynski [2020] Belczynski, K., Dec. 2020. The Most Ordinary Formation of the Most Unusual Double Black Hole Merger. ApJL 905 (2), L15.
  * Belczynski et al. [2010] Belczynski, K., Bulik, T., Fryer, C. L., Ruiter, A., Valsecchi, F., Vink, J. S., Hurley, J. R., May 2010. On the Maximum Mass of Stellar Black Holes. ApJ 714, 1217–1226.
  * Belczynski et al. [2002] Belczynski, K., Kalogera, V., Bulik, T., Jun. 2002. A Comprehensive Study of Binary Compact Objects as Gravitational Wave Sources: Evolutionary Channels, Rates, and Physical Properties. ApJ 572, 407–431.
  * Belczynski et al. [2008] Belczynski, K., Kalogera, V., Rasio, F. A., Taam, R. E., Zezas, A., Bulik, T., Maccarone, T. J., Ivanova, N., Jan. 2008. Compact Object Modeling with the StarTrack Population Synthesis Code. ApJs 174, 223–260.
  * Belczynski et al. [2020] Belczynski, K., Klencki, J., Fields, C. E., Olejak, A., Berti, E., Meynet, G., Fryer, C. L., Holz, D. E., O’Shaughnessy, R., Brown, D. A., Bulik, T., Leung, S. C., Nomoto, K., Madau, P., Hirschi, R., Kaiser, E., Jones, S., Mondal, S., Chruslinska, M., Drozda, P., Gerosa, D., Doctor, Z., Giersz, M., Ekstrom, S., Georgy, C., Askar, A., Baibhav, V., Wysocki, D., Natan, T., Farr, W. M., Wiktorowicz, G., Coleman Miller, M., Farr, B., Lasota, J. P., Apr. 2020\. Evolutionary roads leading to low effective spins, high black hole masses, and O1/O2 rates for LIGO/Virgo binary black holes. A&A 636, A104.
  * Belloni and Altamirano [2013] Belloni, T. M., Altamirano, D., Jun. 2013. High-frequency quasi-periodic oscillations from GRS 1915+105. MNRAS 432 (1), 10–18.
  * Berghea and Dudik [2012] Berghea, C. T., Dudik, R. P., Jun. 2012. Spitzer Observations of MF 16 Nebula and the Associated Ultraluminous X-Ray Source. ApJ 751 (2), 104.
  * Berghea et al. [2010a] Berghea, C. T., Dudik, R. P., Weaver, K. A., Kallman, T. R., Jan. 2010a. The First Detection of [O IV] from an Ultraluminous X-Ray Source with Spitzer. I. Observational Results for Holmberg II ULX. ApJ 708 (1), 354–363.
  * Berghea et al. [2010b] Berghea, C. T., Dudik, R. P., Weaver, K. A., Kallman, T. R., Jan. 2010b. The First Detection of [O IV] from an Ultraluminous X-ray Source with Spitzer. II. Evidence for High Luminosity in Holmberg II ULX. ApJ 708 (1), 364–374.
  * Bhattacharya and van den Heuvel [1991] Bhattacharya, D., van den Heuvel, E. P. J., Jan. 1991. Formation and evolution of binary and millisecond radio pulsars. Physical Reports 203 (1-2), 1–124.
  * Binder et al. [2018] Binder, B., Levesque, E. M., Dorn-Wallenstein, T., Aug. 2018. No Strong Geometric Beaming in the Ultraluminous Neutron Star Binary NGC 300 ULX-1 (SN 2010da) from Swift and Gemini. ApJ 863 (2), 141.
  * Bonnet-Bidaud and van der Klis [1981] Bonnet-Bidaud, J. M., van der Klis, M., Apr. 1981. Long term X-ray observations of SMC X-1 including a turn-on. A&A 97, 134–138.
  * Brice et al. [2021] Brice, N., Zane, S., Turolla, R., Wu, K., Jun. 2021. Super-eddington emission from accreting, highly magnetized neutron stars with a multipolar magnetic field. MNRAS 504 (1), 701–715.
  * Brightman et al. [2020a] Brightman, M., Earnshaw, H., Fürst, F., Harrison, F. A., Heida, M., Israel, G., Pike, S., Stern, D., Walton, D. J., Jun. 2020a. Swift Monitoring of M51: A 38 day Superorbital Period for the Pulsar ULX7 and a New Transient Ultraluminous X-Ray Source. ApJ 895 (2), 127.
  * Brightman et al. [2016] Brightman, M., Harrison, F., Walton, D. J., Fuerst, F., Hornschemeier, A., Zezas, A., Bachetti, M., Grefenstette, B., Ptak, A., Tendulkar, S., Yukita, M., Jan. 2016. Spectral and Temporal Properties of the Ultraluminous X-Ray Pulsar in M82 from 15 years of Chandra Observations and Analysis of the Pulsed Emission Using NuSTAR. ApJ 816 (2), 60\.
  * Brightman et al. [2019] Brightman, M., Harrison, F. A., Bachetti, M., Xu, Y., Fürst, F., Walton, D. J., Ptak, A., Yukita, M., Zezas, A., Mar. 2019. A $\sim$60 day Super-orbital Period Originating from the Ultraluminous X-Ray Pulsar in M82. ApJ 873 (2), 115.
  * Brightman et al. [2018] Brightman, M., Harrison, F. A., Fürst, F., Middleton, M. J., Walton, D. J., Stern, D., Fabian, A. C., Heida, M., Barret, D., Bachetti, M., Apr. 2018. Magnetic field strength of a neutron-star-powered ultraluminous X-ray source. Nature Astronomy 2, 312–316.
  * Brightman et al. [2020b] Brightman, M., Walton, D. J., Xu, Y., Earnshaw, H. P., Harrison, F. A., Stern, D., Barret, D., Jan. 2020b. Spectral Evolution of the Ultraluminous X-Ray Sources M82 X-1 and X-2. ApJ 889 (1), 71\.
  * Brorby et al. [2014] Brorby, M., Kaaret, P., Prestwich, A., Jul. 2014. X-ray binary formation in low-metallicity blue compact dwarf galaxies. MNRAS 441 (3), 2346–2353.
  * Bykov et al. [2022] Bykov, S. D., Gilfanov, M. R., Tsygankov, S. S., Filippova, E. V., Oct. 2022\. ULX pulsar Swift J0243.6+6124 observations with NuSTAR: dominance of reflected emission in the super-Eddington state. MNRAS 516 (2), 1601–1611.
  * Campana et al. [2008] Campana, S., Stella, L., Kennea, J. A., Sep. 2008. Swift Observations of SAX J1808.4-3658: Monitoring the Return to Quiescence. ApJL 684 (2), L99.
  * Canuto et al. [1971] Canuto, V., Lodenquai, J., Ruderman, M., May 1971. Thomson Scattering in a Strong Magnetic Field. Phys. Rev. D 3 (10), 2303–2308.
  * Cappelluti et al. [2011] Cappelluti, N., Predehl, P., Böhringer, H., Brunner, H., Brusa, M., Burwitz, V., Churazov, E., Dennerl, K., Finoguenov, A., Freyberg, M., Friedrich, P., Hasinger, G., Kenziorra, E., Kreykenbohm, I., Lamer, G., Meidinger, N., Mühlegger, M., Pavlinsky, M., Robrade, J., Santangelo, A., Schmitt, J., Schwope, A., Steinmitz, M., Strüder, L., Sunyaev, R., Tenzer, C., Jan 2011\. eROSITA on SRG. A X-ray all-sky survey mission. Memorie della Societa Astronomica Italiana Supplementi 17, 159.
  * Carpano et al. [2018] Carpano, S., Haberl, F., Maitra, C., Vasilopoulos, G., May 2018. Discovery of pulsations from NGC 300 ULX1 and its fast period evolution. MNRAS 476, L45–L49.
  * Castro-Tirado et al. [1992] Castro-Tirado, A. J., Brandt, S., Lund, N., Aug. 1992. GRS 1915+105. IAU Circ 5590, 2.
  * Chandra et al. [2020] Chandra, A. D., Roy, J., Agrawal, P. C., Choudhury, M., Jul. 2020. Study of recent outburst in the Be/X-ray binary RX J0209.6-7427 with AstroSat: a new ultraluminous X-ray pulsar in the Magellanic Bridge? MNRAS 495 (3), 2664–2672.
  * Chashkina et al. [2017] Chashkina, A., Abolmasov, P., Poutanen, J., Sep. 2017. Super-Eddington accretion on to a magnetized neutron star. MNRAS 470 (3), 2799–2813.
  * Chashkina et al. [2019] Chashkina, A., Lipunova, G., Abolmasov, P., Poutanen, J., Jun. 2019. Super-Eddington accretion discs with advection and outflows around magnetized neutron stars. A&A 626, A18.
  * Christodoulou et al. [2019] Christodoulou, D. M., Laycock, S. G. T., Kazanas, D., Oct. 2019. Meta-analysis of electron cyclotron resonance absorption features detected in high-mass X-ray binaries. Research in Astronomy and Astrophysics 19 (10), 146\.
  * Churazov et al. [2001] Churazov, E., Gilfanov, M., Revnivtsev, M., Mar. 2001. Soft state of Cygnus X-1: stable disc and unstable corona. MNRAS 321 (4), 759–766.
  * Clark et al. [2014] Clark, J. S., Ritchie, B. W., Najarro, F., Langer, N., Negueruela, I., May 2014. A VLT/FLAMES survey for massive binaries in Westerlund 1. IV. Wd1-5 - binary product and a pre-supernova companion for the magnetar CXOU J1647-45? A&A 565, A90.
  * Colbert and Mushotzky [1999] Colbert, E. J. M., Mushotzky, R. F., Jul. 1999. The Nature of Accreting Black Holes in Nearby Galaxy Nuclei. ApJ 519, 89–107.
  * Copperwheat et al. [2007] Copperwheat, C., Cropper, M., Soria, R., Wu, K., Apr. 2007. Irradiation models for ULXs and fits to optical data. MNRAS 376 (3), 1407–1423.
  * Corbet et al. [2004] Corbet, R. H. D., Laycock, S., Coe, M. J., Marshall, F. E., Markwardt, C. B., Jul. 2004. Monitoring and Discovering X-ray Pulsars in the Small Magellanic Cloud. In: Kaaret, P., Lamb, F. K., Swank, J. H. (Eds.), X-ray Timing 2003: Rossi and Beyond. Vol. 714 of American Institute of Physics Conference Series. pp. 337–341.
  * Coriat et al. [2009] Coriat, M., Corbel, S., Buxton, M. M., Bailyn, C. D., Tomsick, J. A., Körding, E., Kalemci, E., Nov. 2009. The infrared/X-ray correlation of GX 339-4: probing hard X-ray emission in accreting black holes. MNRAS 400, 123–133.
  * Coriat et al. [2012] Coriat, M., Fender, R. P., Dubus, G., Aug. 2012. Revisiting a fundamental test of the disc instability model for X-ray binaries. MNRAS 424, 1991–2001.
  * Cseh et al. [2012] Cseh, D., Corbel, S., Kaaret, P., Lang, C., Grisé, F., Paragi, Z., Tzioumis, A., Tudose, V., Feng, H., Apr. 2012. Black Hole Powered Nebulae and a Case Study of the Ultraluminous X-Ray Source IC 342 X-1. ApJ 749 (1), 17.
  * Cseh et al. [2013] Cseh, D., Grisé, F., Kaaret, P., Corbel, S., Scaringi, S., Groot, P., Falcke, H., Körding, E., Nov. 2013. Towards a dynamical mass of the ultraluminous X-ray source NGC 5408 X-1. MNRAS 435 (4), 2896–2902.
  * Cseh et al. [2014] Cseh, D., Kaaret, P., Corbel, S., Grise, F., Lang, C., Kording, E., Falcke, H., Jonker, P. G., Miller-Jones, J. C. A., Farrell, S., Yang, Y. J., Paragi, Z., Frey, S., Mar. 2014. Unveiling recurrent jets of the ULX Holmberg II X-1: evidence for a massive stellar-mass black hole? MNRAS 439, L1–L5.
  * Cseh et al. [2015] Cseh, D., Miller-Jones, J. C. A., Jonker, P. G., Grisé, F., Paragi, Z., Corbel, S., Falcke, H., Frey, S., Kaaret, P., Körding, E., Sep. 2015. The evolution of a jet ejection of the ultraluminous X-ray source Holmberg II X-1. MNRAS 452 (1), 24–31.
  * Cui [1997] Cui, W., Jun. 1997. Evidence for “Propeller” Effects in X-Ray Pulsars GX 1+4 and GRO J1744-28. ApJL 482 (2), L163–L166.
  * Dage et al. [2021] Dage, K. C., Kundu, A., Thygesen, E., Bahramian, A., Haggard, D., Irwin, J. A., Maccarone, T. J., Nair, S., Peacock, M. B., Strader, J., Zepf, S. E., Mar. 2021. Three Ultraluminous X-ray Sources Hosted by Globular Clusters in NGC 1316. arXiv e-prints, arXiv:2103.16576.
  * Dage et al. [2019] Dage, K. C., Zepf, S. E., Peacock, M. B., Bahramian, A., Noroozi, O., Kundu, A., Maccarone, T. J., May 2019. X-ray spectral variability of ultraluminous X-ray sources in extragalactic globular clusters. MNRAS 485 (2), 1694–1707.
  * Dage et al. [2020] Dage, K. C., Zepf, S. E., Thygesen, E., Bahramian, A., Kundu, A., Maccarone, T. J., Peacock, M. B., Strader, J., Sep. 2020. X-ray spectroscopy of newly identified ULXs associated with M87’s globular cluster population. MNRAS 497 (1), 596–608.
  * Dai and Li [2006] Dai, H. L., Li, X. D., May 2006. Accretion torque on magnetized neutron stars. A&A 451 (2), 581–585.
  * Dall’Osso et al. [2015] Dall’Osso, S., Perna, R., Papitto, A., Bozzo, E., Stella, L., Dec. 2015\. The accretion regimes of a highly magnetised NS: the unique case of NuSTAR J095551+6940.8. ArXiv e-prints.
  * Dauser et al. [2017] Dauser, T., Middleton, M., Wilms, J., Apr. 2017. Modelling the light curves of ultraluminous X-ray sources as precession. MNRAS 466, 2236–2241.
  * Davis et al. [2011] Davis, S. W., Narayan, R., Zhu, Y., Barret, D., Farrell, S. A., Godet, O., Servillat, M., Webb, N. A., Jun. 2011. The Cool Accretion Disk in ESO 243-49 HLX-1: Further Evidence of an Intermediate-mass Black Hole. ApJ 734 (2), 111.
  * De Marco et al. [2013] De Marco, B., Ponti, G., Miniutti, G., Belloni, T., Cappi, M., Dadina, M., Muñoz-Darias, T., Dec. 2013. Time lags in the ultraluminous X-ray source NGC 5408 X-1: implications for the black hole mass. MNRAS 436 (4), 3782–3791.
  * Dewangan et al. [2006] Dewangan, G. C., Griffiths, R. E., Rao, A. R., Apr. 2006. Quasi-periodic Oscillations and Strongly Comptonized X-Ray Emission from Holmberg IX X-1. ApJL 641 (2), L125–L128.
  * Dib and Kaspi [2014] Dib, R., Kaspi, V. M., Mar. 2014. 16 yr of RXTE Monitoring of Five Anomalous X-Ray Pulsars. ApJ 784 (1), 37.
  * Dib et al. [2009] Dib, R., Kaspi, V. M., Gavriil, F. P., Sep. 2009. Rossi X-Ray Timing Explorer Monitoring of the Anomalous X-ray Pulsar 1E 1048.1 - 5937: Long-term Variability and the 2007 March Event. ApJ 702 (1), 614–630.
  * Dolan et al. [1997] Dolan, J. F., Boyd, P. T., Fabrika, S., Tapia, S., Bychkov, V., Panferov, A. A., Nelson, M. J., Percival, J. W., van Citters, G. W., Taylor, D. C., Taylor, M. J., Nov. 1997. SS 433 in the ultraviolet. A&A 327, 648–655.
  * Dominik et al. [2012] Dominik, M., Belczynski, K., Fryer, C., Holz, D. E., Berti, E., Bulik, T., Mandel, I., O’Shaughnessy, R., Nov. 2012. Double Compact Objects. I. The Significance of the Common Envelope on Merger Rates. ApJ 759, 52.
  * Done et al. [2007] Done, C., Gierliński, M., Kubota, A., Dec. 2007. Modelling the behaviour of accretion flows in X-ray binaries. Everything you always wanted to know about accretion but were afraid to ask. A&Ar 15 (1), 1–66.
  * Dopita et al. [2012] Dopita, M. A., Payne, J. L., Filipović, M. D., Pannuti, T. G., Dec. 2012\. The physical parameters of the microquasar S26 in the Sculptor Group galaxy NGC 7793. MNRAS 427 (2), 956–967.
  * Doroshenko et al. [2015] Doroshenko, V., Santangelo, A., Ducci, L., Jul. 2015. Searching for coherent pulsations in ultraluminous X-ray sources. A&A 579, A22.
  * Doroshenko et al. [2018] Doroshenko, V., Tsygankov, S., Santangelo, A., May 2018. Orbit and intrinsic spin-up of the newly discovered transient X-ray pulsar Swift J0243.6+6124. A&A 613, A19.
  * Dubus et al. [2001] Dubus, G., Hameury, J.-M., Lasota, J.-P., Jul. 2001. The disc instability model for X-ray transients: Evidence for truncation and irradiation. A&A 373, 251–271.
  * Dubus et al. [1999] Dubus, G., Lasota, J.-P., Hameury, J.-M., Charles, P., Feb. 1999. X-ray irradiation in low-mass binary systems. MNRAS 303, 139–147.
  * Dudik et al. [2016] Dudik, R. P., Berghea, C. T., Roberts, T. P., Grisé, F., Singh, A., Pagano, R., Winter, L. M., Nov. 2016. Spitzer IRAC Observations of IR Excess in Holmberg IX X-1: A Circumbinary Disk or a Variable Jet? ApJ 831 (1), 88.
  * Duncan and Thompson [1992] Duncan, R. C., Thompson, C., Jun. 1992. Formation of Very Strongly Magnetized Neutron Stars: Implications for Gamma-Ray Bursts. ApJL 392, L9.
  * Earnshaw et al. [2020] Earnshaw, H. P., Heida, M., Brightman, M., Fürst, F., Harrison, F. A., Jaodand, A., Middleton, M. J., Roberts, T. P., Sathyaprakash, R., Stern, D., Walton, D. J., Mar. 2020. The (Re)appearance of NGC 925 ULX-3, a New Transient ULX. ApJ 891 (2), 153.
  * Earnshaw et al. [2019] Earnshaw, H. P., Roberts, T. P., Middleton, M. J., Walton, D. J., Mateos, S., Mar 2019. A new, clean catalogue of extragalactic non-nuclear X-ray sources in nearby galaxies. MNRAS 483 (4), 5554–5573.
  * Earnshaw et al. [2018] Earnshaw, H. P., Roberts, T. P., Sathyaprakash, R., May 2018. Searching for propeller-phase ULXs in the XMM-Newton Serendipitous Source Catalogue. MNRAS 476 (3), 4272–4277.
  * Edge et al. [2004] Edge, W. R. T., Coe, M. J., Galache, J. L., McBride, V. A., Corbet, R. H. D., Markwardt, C. B., Laycock, S., Oct. 2004. Three new X-ray pulsars detected in the Small Magellanic Cloud and the positions of two other known pulsars determined. MNRAS 353 (4), 1286–1292.
  * Eggum et al. [1988] Eggum, G. E., Coroniti, F. V., Katz, J. I., Jul. 1988. Radiation Hydrodynamic Calculation of Super-Eddington Accretion Disks. ApJ 330, 142.
  * Ekşi et al. [2015] Ekşi, K. Y., Andaç, İ. C., Çıkıntoğlu, S., Gençali, A. A., Güngör, C., Öztekin, F., Mar. 2015. The ultraluminous X-ray source NuSTAR J095551+6940.8: a magnetar in a high-mass X-ray binary. MNRAS 448, L40–L42.
  * El Mellah et al. [2019] El Mellah, I., Sundqvist, J. O., Keppens, R., Feb. 2019. Wind Roche lobe overflow in high-mass X-ray binaries. A possible mass-transfer mechanism for ultraluminous X-ray sources. A&A 622, L3.
  * Erkut et al. [2020] Erkut, M. H., Türkoğlu, M. M., Eksi, K. Y., Alpar, M. A., Aug. 2020. On the Magnetic Fields, Beaming Fractions, and Fastness Parameters of Pulsating Ultraluminous X-Ray Sources. ApJ 899 (2), 97\.
  * Evans et al. [2010] Evans, I. N., Primini, F. A., Glotfelty, K. J., Anderson, C. S., Bonaventura, N. R., Chen, J. C., Davis, J. E., Doe, S. M., Evans, J. D., Fabbiano, G., Galle, E. C., Gibbs, Danny G., I., Grier, J. D., Hain, R. M., Hall, D. M., Harbo, P. N., He, X. H., Houck, J. C., Karovska, M., Kashyap, V. L., Lauer, J., McCollough, M. L., McDowell, J. C., Miller, J. B., Mitschang, A. W., Morgan, D. L., Mossman, A. E., Nichols, J. S., Nowak, M. A., Plummer, D. A., Refsdal, B. L., Rots, A. H., Siemiginowska, A., Sundheim, B. A., Tibbetts, M. S., Van Stone, D. W., Winkelman, S. L., Zografou, P., Jul. 2010. The Chandra Source Catalog. ApJs 189 (1), 37–82.
  * Fabbiano [1989] Fabbiano, G., Jan. 1989. X-rays from normal galaxies. ARAA 27, 87–138.
  * Fabbiano et al. [2001] Fabbiano, G., Zezas, A., Murray, S. S., Jun. 2001. Chandra Observations of “The Antennae” Galaxies (NGC 4038/9). ApJ 554, 1035–1043.
  * Fabian and Rees [1979] Fabian, A. C., Rees, M. J., Apr. 1979. SS 433: a double jet in action? MNRAS 187, 13P–16.
  * Fabrika [2004] Fabrika, S., Jan. 2004. The jets and supercritical accretion disk in SS433. ASPRv 12, 1–152.
  * Fabrika et al. [2015] Fabrika, S., Ueda, Y., Vinokurov, A., Sholukhova, O., Shidatsu, M., Jul. 2015. Supercritical accretion disks in ultraluminous X-ray sources and SS 433. Nature Physics 11 (7), 551–553.
  * Fabrika et al. [2021] Fabrika, S. N., Atapin, K. E., Vinokurov, A. S., Sholukhova, O. N., Jan. 2021. Ultraluminous X-Ray Sources. Astrophysical Bulletin 76 (1), 6–38.
  * Falanga et al. [2015] Falanga, M., Bozzo, E., Lutovinov, A., Bonnet-Bidaud, J. M., Fetisova, Y., Puls, J., May 2015. Ephemeris, orbital decay, and masses of ten eclipsing high-mass X-ray binaries. A&A 577, A130.
  * Falcke et al. [2004] Falcke, H., Körding, E., Markoff, S., Feb. 2004. A scheme to unify low-power accreting black holes. Jet-dominated accretion flows and the radio/X-ray correlation. A&A 414, 895–903.
  * Farrell et al. [2009] Farrell, S. A., Webb, N. A., Barret, D., Godet, O., Rodrigues, J. M., Jul. 2009. An intermediate-mass black hole of over 500 solar masses in the galaxy ESO243-49. Nature 460, 73–75.
  * Fender et al. [2009] Fender, R. P., Homan, J., Belloni, T. M., Jul. 2009. Jets from black hole X-ray binaries: testing, refining and extending empirical models for the coupling to X-rays. MNRAS 396 (3), 1370–1382.
  * Fender et al. [1997] Fender, R. P., Pooley, G. G., Brocksopp, C., Newell, S. J., Oct. 1997. Rapid infrared flares in GRS 1915+105: evidence for infrared synchrotron emission. MNRAS 290 (4), L65–L69.
  * Feng and Kaaret [2008] Feng, H., Kaaret, P., Mar. 2008. Optical Counterpart of the Ultraluminous X-Ray Source IC 342 X-1. ApJ 675 (2), 1067–1075.
  * Feng et al. [2016] Feng, H., Tao, L., Kaaret, P., Grisé, F., nov 2016. Nature of the soft ulx in ngc 247: Super-eddington outflow and transition between the supersoft and soft ultraluminous regimes. The Astrophysical Journal 831 (2), 117.
URL https://dx.doi.org/10.3847/0004-637X/831/2/117

  * Ferland et al. [1998] Ferland, G. J., Korista, K. T., Verner, D. A., Ferguson, J. W., Kingdon, J. B., Verner, E. M., Jul. 1998. CLOUDY 90: Numerical Simulation of Plasmas and Their Spectra. PASP 110 (749), 761–778.
  * Finke and Razzaque [2017] Finke, J. D., Razzaque, S., Dec. 2017. The binary black hole merger rate from ultraluminous X-ray source progenitors. MNRAS 472, 3683–3691.
  * Fragile et al. [2007] Fragile, P. C., Blaes, O. M., Anninos, P., Salmonson, J. D., Oct 2007. Global General Relativistic Magnetohydrodynamic Simulation of a Tilted Black Hole Accretion Disk. ApJ 668 (1), 417–429.
  * Fragos et al. [2013] Fragos, T., Lehmer, B. D., Naoz, S., Zezas, A., Basu-Zych, A., Oct. 2013\. Energy Feedback from X-Ray Binaries in the Early Universe. ApJL 776 (2), L31.
  * Frank et al. [2002] Frank, J., King, A., Raine, D. J., Jan. 2002. Accretion Power in Astrophysics: Third Edition.
  * Fuchs et al. [2006] Fuchs, Y., Koch Miramond, L., Ábrahám, P., Jan. 2006. SS 433: a phenomenon imitating a Wolf-Rayet star. A&A 445 (3), 1041–1052.
  * Fuerst et al. [2021] Fuerst, F., Walton, D. J., Heida, M., Bachetti, M., Pinto, C., Middleton, M. J., Brightman, M., Earnshaw, H. P., Barret, D., Fabian, A. C., Kretschmar, P., Pottschmidt, K., Ptak, A., Roberts, T., Stern, D., Webb, N., Wilms, J., May 2021. Long-term pulse period evolution of the ultra-luminous X-ray pulsar NGC 7793 P13. arXiv e-prints, arXiv:2105.04229.
  * Fürst et al. [2016] Fürst, F., Walton, D. J., Harrison, F. A., Stern, D., Barret, D., Brightman, M., Fabian, A. C., Grefenstette, B., Madsen, K. K., Middleton, M. J., Miller, J. M., Pottschmidt, K., Ptak, A., Rana, V., Webb, N., Nov. 2016. Discovery of Coherent Pulsations from the Ultraluminous X-Ray Source NGC 7793 P13. ApJL 831, L14.
  * Fürst et al. [2017] Fürst, F., Walton, D. J., Stern, D., Bachetti, M., Barret, D., Brightman, M., Harrison, F. A., Rana, V., Jan. 2017. Spectral Changes in the Hyperluminous Pulsar in NGC 5907 as a Function of Super-orbital Phase. ApJ 834 (1), 77.
  * Galloway et al. [2004] Galloway, D. K., Morgan, E. H., Levine, A. M., Oct. 2004. A Frequency Glitch in an Accreting Pulsar. ApJ 613 (2), 1164–1172.
  * Gandhi et al. [2010] Gandhi, P., Dhillon, V. S., Durant, M., Fabian, A. C., Kubota, A., Makishima, K., Malzac, J., Marsh, T. R., Miller, J. M., Shahbaz, T., Spruit, H. C., Casella, P., Oct. 2010. Rapid optical and X-ray timing observations of GX339-4: multicomponent optical variability in the low/hard state. MNRAS 407 (4), 2166–2192.
  * Gao et al. [2003] Gao, Y., Wang, Q. D., Appleton, P. N., Lucas, R. A., Oct. 2003. Nonnuclear Hyper/Ultraluminous X-Ray Sources in the Starbursting Cartwheel Ring Galaxy. ApJL 596, L171–L174.
  * Ghosh and Lamb [1979] Ghosh, P., Lamb, F. K., Aug. 1979. Accretion by rotating magnetic neutron stars. II. Radial and vertical structure of the transition zone in disk accretion. ApJ 232, 259–276.
  * Giacomazzo and Perna [2013] Giacomazzo, B., Perna, R., Jul. 2013. Formation of Stable Magnetars from Binary Neutron Star Mergers. ApJL 771 (2), L26.
  * Gilfanov et al. [2000] Gilfanov, M., Churazov, E., Revnivtsev, M., Aug. 2000. Frequency-resolved spectroscopy of Cyg X-1: fast variability of the reflected emission in the soft state. MNRAS 316 (4), 923–928.
  * Gladstone et al. [2013] Gladstone, J. C., Copperwheat, C., Heinke, C. O., Roberts, T. P., Cartwright, T. F., Levan, A. J., Goad, M. R., Jun. 2013. Optical Counterparts of the Nearest Ultraluminous X-Ray Sources. ApJs 206 (2), 14.
  * Gladstone et al. [2009] Gladstone, J. C., Roberts, T. P., Done, C., Aug. 2009. The ultraluminous state. MNRAS 397 (4), 1836–1851.
  * Goad et al. [2002] Goad, M. R., Roberts, T. P., Knigge, C., Lira, P., Sep. 2002. The optical counterpart of the ultraluminous X-ray source NGC 5204 X-1. MNRAS 335 (3), L67–L70.
  * Godet et al. [2014] Godet, O., Lombardi, J. C., Antonini, F., Barret, D., Webb, N. A., Vingless, J., Thomas, M., Oct. 2014. Implications of the Delayed 2013 Outburst of ESO 243-49 HLX-1. ApJ 793, 105.
  * González Hernández et al. [2017] González Hernández, J. I., Suárez-Andrés, L., Rebolo, R., Casares, J., Feb. 2017. Extremely fast orbital decay of the black hole X-ray binary Nova Muscae 1991. MNRAS 465 (1), L15–L19.
  * Greene et al. [2020] Greene, J. E., Strader, J., Ho, L. C., Aug. 2020. Intermediate-Mass Black Holes. ARAA 58, 257–312.
  * Grisé et al. [2013] Grisé, F., Kaaret, P., Corbel, S., Cseh, D., Feng, H., Aug. 2013. A long-term X-ray monitoring of the ultraluminous X-ray source NGC 5408 X-1 with Swift reveals the presence of dips but no orbital period. MNRAS 433 (2), 1023–1038.
  * Grisé et al. [2012] Grisé, F., Kaaret, P., Corbel, S., Feng, H., Cseh, D., Tao, L., Feb. 2012. Optical Emission of the Ultraluminous X-Ray Source NGC 5408 X-1: Donor Star or Irradiated Accretion Disk? ApJ 745 (2), 123.
  * Grisé et al. [2006] Grisé, F., Pakull, M. W., Motch, C., Jan. 2006. The Ultraluminous X-ray Source in Holmberg IX and its Environment. In: Meurs, E. J. A., Fabbiano, G. (Eds.), Populations of High Energy Sources in Galaxies. Vol. 230\. pp. 302–303.
  * Grisé et al. [2008] Grisé, F., Pakull, M. W., Soria, R., Motch, C., Smith, I. A., Ryder, S. D., Böttcher, M., Jul. 2008. The ultraluminous X-ray source NGC 1313 X-2. Its optical counterpart and environment. A&A 486 (1), 151–163.
  * Gültekin et al. [2009] Gültekin, K., Cackett, E. M., Miller, J. M., Di Matteo, T., Markoff, S., Richstone, D. O., Nov. 2009. The Fundamental Plane of Accretion onto Black Holes with Dynamical Masses. ApJ 706 (1), 404–416.
  * Gúrpide et al. [2021] Gúrpide, A., Godet, O., Koliopanos, F., Webb, N., Olive, J.-F., Feb. 2021. Long-term X-ray spectral evolution of Ultraluminous X-ray sources: implications on the accretion flow geometry and the nature of the accretor. arXiv e-prints, arXiv:2102.11159.
  * Gúrpide et al. [2022] Gúrpide, A., Parra, M., Godet, O., Contini, T., Olive, J. F., Oct. 2022. MUSE spectroscopy of the ULX NGC 1313 X-1: A shock-ionised bubble, an X-ray photoionised nebula, and two supernova remnants. A&A 666, A100.
  * Hameury [2020] Hameury, J. M., Sep. 2020. A review of the disc instability model for dwarf novae, soft X-ray transients and related objects. Advances in Space Research 66 (5), 1004–1024.
  * Hameury and Lasota [2020] Hameury, J. M., Lasota, J. P., Nov. 2020. Models of ultraluminous X-ray transient sources. A&A 643, A171.
  * Harrison et al. [2013] Harrison, F. A., Craig, W. W., Christensen, F. E., Hailey, C. J., Zhang, W. W., Boggs, S. E., Stern, D., Cook, W. R., Forster, K., Giommi, P., Grefenstette, B. W., Kim, Y., Kitaguchi, T., Koglin, J. E., Madsen, K. K., Mao, P. H., Miyasaka, H., Mori, K., Perri, M., Pivovaroff, M. J., Puccetti, S., Rana, V. R., Westergaard, N. J., Willis, J., Zoglauer, A., An, H., Bachetti, M., Barrière, N. M., Bellm, E. C., Bhalerao, V., Brejnholt, N. F., Fuerst, F., Liebe, C. C., Markwardt, C. B., Nynka, M., Vogel, J. K., Walton, D. J., Wik, D. R., Alexander, D. M., Cominsky, L. R., Hornschemeier, A. E., Hornstrup, A., Kaspi, V. M., Madejski, G. M., Matt, G., Molendi, S., Smith, D. M., Tomsick, J. A., Ajello, M., Ballantyne, D. R., Baloković, M., Barret, D., Bauer, F. E., Blandford, R. D., Brandt, W. N., Brenneman, L. W., Chiang, J., Chakrabarty, D., Chenevez, J., Comastri, A., Dufour, F., Elvis, M., Fabian, A. C., Farrah, D., Fryer, C. L., Gotthelf, E. V., Grindlay, J. E., Helfand, D. J., Krivonos, R., Meier, D. L., Miller, J. M., Natalucci, L., Ogle, P., Ofek, E. O., Ptak, A., Reynolds, S. P., Rigby, J. R., Tagliaferri, G., Thorsett, S. E., Treister, E., Urry, C. M., Jun. 2013. The Nuclear Spectroscopic Telescope Array (NuSTAR) High-energy X-Ray Mission. ApJ 770 (2), 103.
  * Hashizume et al. [2015] Hashizume, K., Ohsuga, K., Kawashima, T., Tanaka, M., Aug. 2015. Radiation hydrodynamics simulations of wide-angle outflows from super-critical accretion disks around black holes. PASJ 67 (4), 58.
  * Heida et al. [2019a] Heida, M., Harrison, F. A., Brightman, M., Fürst, F., Stern, D., Walton, D. J., Feb. 2019a. Searching for the Donor Stars of ULX Pulsars. ApJ 871 (2), 231.
  * Heida et al. [2014] Heida, M., Jonker, P. G., Torres, M. A. P., Kool, E., Servillat, M., Roberts, T. P., Groot, P. J., Walton, D. J., Moon, D. S., Harrison, F. A., Aug. 2014. Near-infrared counterparts of ultraluminous X-ray sources. MNRAS 442 (2), 1054–1067.
  * Heida et al. [2016] Heida, M., Jonker, P. G., Torres, M. A. P., Roberts, T. P., Walton, D. J., Moon, D. S., Stern, D., Harrison, F. A., Jun. 2016. Keck/MOSFIRE spectroscopy of five ULX counterparts. MNRAS 459 (1), 771–778.
  * Heida et al. [2019b] Heida, M., Lau, R. M., Davies, B., Brightman, M., Fürst, F., Grefenstette, B. W., Kennea, J. A., Tramper, F., Walton, D. J., Harrison, F. A., Oct 2019b. Discovery of a Red Supergiant Donor Star in SN2010da/NGC 300 ULX-1. ApJL 883 (2), L34.
  * Heil and Vaughan [2010] Heil, L. M., Vaughan, S., Jun. 2010. The linear rms-flux relation in an ultraluminous X-ray source. MNRAS 405 (1), L86–L89.
  * Heil et al. [2009] Heil, L. M., Vaughan, S., Roberts, T. P., Aug. 2009. A systematic study of variability in a sample of ultraluminous X-ray sources. MNRAS 397 (2), 1061–1072.
  * Hernández-García et al. [2015] Hernández-García, L., Vaughan, S., Roberts, T. P., Middleton, M., Nov. 2015. X-ray time lags and non-linear variability in the ultraluminous X-ray sources NGC 5408 X-1 and NGC 6946 X-1. MNRAS 453 (3), 2877–2884.
  * Herold [1979] Herold, H., May 1979. Compton and Thomson scattering in strong magnetic fields. Phys. Rev. D 19 (10), 2868–2875.
  * Hu et al. [2017] Hu, C.-P., Li, K. L., Kong, A. K. H., Ng, C. Y., Lin, L. C.-C., Jan. 2017\. Swift Detection of a 65 Day X-Ray Period from the Ultraluminous Pulsar NGC 7793 P13. ApJL 835 (1), L9.
  * Hu et al. [2022] Hu, H., Inayoshi, K., Haiman, Z., Quataert, E., Kuiper, R., Mar. 2022\. Long-term evolution of supercritical black hole accretion with outflows: a subgrid feedback model for cosmological simulations. arXiv e-prints, arXiv:2203.14994.
  * Iłkiewicz et al. [2019] Iłkiewicz, K., Mikołajewska, J., Belczyński, K., Wiktorowicz, G., Karczmarek, P., Jun. 2019. Wind Roche lobe overflow as a way to make Type Ia supernovae from the widest symbiotic systems. MNRAS 485 (4), 5468–5473.
  * Inayoshi et al. [2018] Inayoshi, K., Ostriker, J. P., Haiman, Z., Kuiper, R., May 2018. Low-density, radiatively inefficient rotating-accretion flow on to a black hole. MNRAS 476 (1), 1412–1426.
  * Inoue et al. [2020] Inoue, A., Ohsuga, K., Kawashima, T., Apr. 2020. Pulsed fraction of super-critical column accretion flows on to neutron stars: Modeling of ultraluminous X-ray pulsars. PASJ 72 (2), 34.
  * Irwin et al. [2010] Irwin, J. A., Brink, T. G., Bregman, J. N., Roberts, T. P., Mar. 2010. Evidence for a Stellar Disruption by an Intermediate-mass Black Hole in an Extragalactic Globular Cluster. ApJL 712 (1), L1–L4.
  * Israel et al. [2017a] Israel, G. L., Belfiore, A., Stella, L., Esposito, P., Casella, P., De Luca, A., Marelli, M., Papitto, A., Perri, M., Puccetti, S., Castillo, G. A. R., Salvetti, D., Tiengo, A., Zampieri, L., D’Agostino, D., Greiner, J., Haberl, F., Novara, G., Salvaterra, R., Turolla, R., Watson, M., Wilms, J., Wolter, A., Feb. 2017a. An accreting pulsar with extreme properties drives an ultraluminous x-ray source in NGC 5907. Science 355 (6327), 817–819.
  * Israel et al. [2017b] Israel, G. L., Papitto, A., Esposito, P., Stella, L., Zampieri, L., Belfiore, A., Rodríguez Castillo, G. A., De Luca, A., Tiengo, A., Haberl, F., Greiner, J., Salvaterra, R., Sandrelli, S., Lisini, G., Mar. 2017b. Discovery of a 0.42-s pulsar in the ultraluminous X-ray source NGC 7793 P13. MNRAS 466, L48–L52.
  * Ivanova et al. [2010] Ivanova, N., Chaichenets, S., Fregeau, J., Heinke, C. O., Lombardi, J. C., J., Woods, T. E., Jul. 2010. Formation of Black Hole X-ray Binaries in Globular Clusters. ApJ 717 (2), 948–957.
  * Jaisawal and Naik [2016] Jaisawal, G. K., Naik, S., Sep. 2016. Detection of cyclotron resonance scattering feature in high-mass X-ray binary pulsar SMC X-2. MNRAS 461 (1), L97–L101.
  * Jansen et al. [2001] Jansen, F., Lumb, D., Altieri, B., Clavel, J., Ehle, M., Erd, C., Gabriel, C., Guainazzi, M., Gondoin, P., Much, R., Munoz, R., Santos, M., Schartel, N., Texier, D., Vacanti, G., Jan. 2001. XMM-Newton observatory. I. The spacecraft and operations. A&A 365, L1–L6.
  * Jaroszynski et al. [1980] Jaroszynski, M., Abramowicz, M. A., Paczynski, B., Jan. 1980. Supercritical accretion disks around black holes. AcA 30 (1), 1–34.
  * Jenke and Wilson-Hodge [2017] Jenke, P., Wilson-Hodge, C. A., Oct. 2017. Fermi GBM detects pulsations from Swift J0243.6+6124. The Astronomer’s Telegram 10812, 1.
  * Jiang et al. [2013] Jiang, Y.-F., Stone, J. M., Davis, S. W., Nov. 2013. On the Thermal Stability of Radiation-dominated Accretion Disks. ApJ 778 (1), 65.
  * Jiang et al. [2014] Jiang, Y.-F., Stone, J. M., Davis, S. W., Dec. 2014. A Global Three-dimensional Radiation Magneto-hydrodynamic Simulation of Super-Eddington Accretion Disks. ApJ 796, 106.
  * Jiang et al. [2019a] Jiang, Y.-F., Stone, J. M., Davis, S. W., Aug. 2019a. Super-Eddington Accretion Disks around Supermassive Black Holes. ApJ 880 (2), 67.
  * Jiang et al. [2019b] Jiang, Y.-F., Stone, J. M., Davis, S. W., Aug. 2019b. Super-Eddington Accretion Disks around Supermassive Black Holes. ApJ 880 (2), 67.
  * Jones and Andersson [2001] Jones, D. I., Andersson, N., Jul. 2001. Freely precessing neutron stars: model and observations. MNRAS 324 (4), 811–824.
  * Kaaret and Corbel [2009] Kaaret, P., Corbel, S., May 2009. A Photoionized Nebula Surrounding and Variable Optical Continuum Emission from the Ultraluminous X-Ray Source in NGC 5408. ApJ 697 (1), 950–956.
  * Kaaret et al. [2003] Kaaret, P., Corbel, S., Prestwich, A. H., Zezas, A., Jan. 2003. Radio Emission from an Ultraluminous X-ray Source. Science 299 (5605), 365–368.
  * Kaaret and Feng [2007] Kaaret, P., Feng, H., Nov. 2007. Confirmation of the 62 Day X-Ray Periodicity from M82. ApJ 669 (1), 106–108.
  * Kaaret et al. [2017] Kaaret, P., Feng, H., Roberts, T. P., Aug. 2017. Ultraluminous X-Ray Sources. ARAA 55, 303–341.
  * Kaaret et al. [2010] Kaaret, P., Feng, H., Wong, D. S., Tao, L., May 2010. Direct Detection of an Ultraluminous Ultraviolet Source. ApJL 714 (1), L167–L170.
  * Kaaret et al. [2006] Kaaret, P., Simet, M. G., Lang, C. C., Jan 2006. The orbital period of the ultraluminous X-ray source in M 82. Science 311, 491–491.
  * Kaaret et al. [2004] Kaaret, P., Ward, M. J., Zezas, A., Jul. 2004. High-resolution imaging of the HeII $\lambda$4686 emission line nebula associated with the ultraluminous X-ray source in Holmberg II. MNRAS 351 (3), L83–L88.
  * Kajava and Poutanen [2008] Kajava, J. J. E., Poutanen, J., Sep 2008. Spectral variability of ultraluminous X-ray sources. In: Axelsson, M. (Ed.), American Institute of Physics Conference Series. Vol. 1054 of American Institute of Physics Conference Series. pp. 39–47.
  * Kajava and Poutanen [2009] Kajava, J. J. E., Poutanen, J., Sep. 2009. Spectral variability of ultraluminous X-ray sources. MNRAS 398, 1450–1460.
  * Kara et al. [2020] Kara, E., Pinto, C., Walton, D. J., Alston, W. N., Bachetti, M., Barret, D., Brightman, M., Canizares, C. R., Earnshaw, H. P., Fabian, A. C., Fürst, F., Kosec, P., Middleton, M. J., Roberts, T. P., Soria, R., Tao, L., Webb, N. A., Feb. 2020. Discovery of a soft X-ray lag in the ultraluminous X-ray source NGC 1313 X-1. MNRAS 491 (4), 5172–5178.
  * Kawashima et al. [2016] Kawashima, T., Mineshige, S., Ohsuga, K., Ogawa, T., Oct. 2016. A radiation-hydrodynamics model of accretion columns for ultra-luminous X-ray pulsars. PASJ 68 (5), 83.
  * Kawashima and Ohsuga [2020] Kawashima, T., Ohsuga, K., Feb. 2020. Super-critical column accretion on to strongly magnetized neutron stars in ULX pulsars. PASJ 72 (1), 15.
  * Kennea et al. [2017] Kennea, J. A., Lien, A. Y., Krimm, H. A., Cenko, S. B., Siegel, M. H., Oct. 2017. Swift J0243.6+6124: Swift discovery of an accreting NS transient. The Astronomer’s Telegram 10809, 1.
  * Khan et al. [2021] Khan, N., Middleton, M. J., Wiktorowicz, G., Dauser, T., Roberts, T. P., Wilms, J., Oct. 2021. The impact of precession on the observed population of ULXs. MNRAS.
  * King [2011] King, A., May 2011. The Brightest Cluster X-ray Sources. ApJL 732, L28.
  * King [2020] King, A., Mar. 2020. GSN 069 - A tidal disruption near miss. MNRAS 493 (1), L120–L123.
  * King [2022] King, A., Jun. 2022. Quasi-Periodic Eruptions from Galaxy Nuclei. MNRAS.
  * King and Lasota [2016] King, A., Lasota, J.-P., May 2016. ULXs: Neutron stars versus black holes. MNRAS 458, L10–L13.
  * King and Lasota [2019] King, A., Lasota, J.-P., May 2019. No magnetars in ULXs. MNRAS 485, 3588–3594.
  * King and Lasota [2020] King, A., Lasota, J.-P., Mar. 2020. Pulsing and Non-Pulsing ULXs: the Iceberg Emerges. arXiv e-prints, arXiv:2003.14019.
  * King and Lasota [2021] King, A., Lasota, J.-P., Dec. 2021. One for the Future: measuring the mass transfer rate in the ULX M82 X-2 by using orbital period changes will take millenia. arXiv e-prints, arXiv:2112.03779.
  * King et al. [2017] King, A., Lasota, J.-P., Kluźniak, W., Jun. 2017. Pulsing ULXs: tip of the iceberg? MNRAS 468, L59–L62.
  * King and Muldrew [2016] King, A., Muldrew, S. I., Jan. 2016. Black hole winds II: Hyper-Eddington winds and feedback. MNRAS 455 (2), 1211–1217.
  * King and Nealon [2019] King, A., Nealon, R., Aug. 2019. Supermassive black hole demographics: evading M - $\sigma$. MNRAS 487 (4), 4827–4831.
  * King and Pounds [2015] King, A., Pounds, K., Aug. 2015. Powerful Outflows and Feedback from Active Galactic Nuclei. ARAA 53, 115–154.
  * King [2002] King, A. R., Sep. 2002. The brightest black holes. MNRAS 335, L13–L16.
  * King [2004] King, A. R., Jan. 2004. Ultraluminous X-ray sources and star formation. MNRAS 347, L18–L20.
  * King [2009] King, A. R., Feb 2009. Masses, beaming and Eddington ratios in ultraluminous X-ray sources. Monthly Notices of the Royal Astronomical Society 393 (1), L41–L44.
  * King and Begelman [1999] King, A. R., Begelman, M. C., Jul. 1999. Radiatively Driven Outflows and Avoidance of Common-Envelope Evolution in Close Binaries. ApJL 519 (2), L169–L171.
  * King et al. [2001] King, A. R., Davies, M. B., Ward, M. J., Fabbiano, G., Elvis, M., May 2001\. Ultraluminous X-Ray Sources in External Galaxies. ApJL 552, L109–L112.
  * King and Pounds [2003] King, A. R., Pounds, K. A., Oct. 2003. Black hole winds. MNRAS 345 (2), 657–659.
  * King and Ritter [1998] King, A. R., Ritter, H., Jan. 1998. The light curves of soft X-ray transients. MNRAS 293 (1), L42–L48.
  * King and Ritter [1999] King, A. R., Ritter, H., Oct. 1999. Cygnus X-2, super-Eddington mass transfer, and pulsar binaries. MNRAS 309, 253–260.
  * King et al. [2000a] King, A. R., Taam, R. E., Begelman, M. C., Feb. 2000a. The Evolutionary Status of SS 433. ApJL 530 (1), L25–L28.
  * King et al. [2000b] King, A. R., Taam, R. E., Begelman, M. C., Feb. 2000b. The Evolutionary Status of SS 433. ApJL 530 (1), L25–L28.
  * Kippenhahn and Weigert [1967] Kippenhahn, R., Weigert, A., Jan. 1967. Entwicklung in engen Doppelsternsystemen I. Massenaustausch vor und nach Beendigung des zentralen Wasserstoff-Brennens. Z. Astrophys. 65, 251.
  * Kitaki et al. [2018] Kitaki, T., Mineshige, S., Ohsuga, K., Kawashima, T., Dec. 2018. Systematic two-dimensional radiation-hydrodynamic simulations of super-Eddington accretion flow and outflow: Comparison with the slim disk model. PASJ 70 (6), 108.
  * Kitaki et al. [2021] Kitaki, T., Mineshige, S., Ohsuga, K., Kawashima, T., Apr. 2021. The origins and impact of outflow from super-Eddington flow. PASJ 73 (2), 450–466.
  * Klencki et al. [2018] Klencki, J., Moe, M., Gladysz, W., Chruslinska, M., Holz, D. E., Belczynski, K., Nov. 2018. Impact of inter-correlated initial binary parameters on double black hole and neutron star mergers. A&A 619, A77.
  * Klochkov et al. [2009] Klochkov, D., Staubert, R., Postnov, K., Shakura, N., Santangelo, A., Nov. 2009. Continuous monitoring of pulse period variations in Hercules X-1 using Swift/BAT. A&A 506 (3), 1261–1267.
  * Kluźniak and Lasota [2015] Kluźniak, W., Lasota, J.-P., Mar. 2015. An ultraluminous nascent millisecond pulsar. MNRAS 448, L43–L47.
  * Koliopanos et al. [2019] Koliopanos, F., Vasilopoulos, G., Buchner, J., Maitra, C., Haberl, F., Jan. 2019. Investigating ULX accretion flows and cyclotron resonance in NGC 300 ULX1. A&A 621, A118.
  * Koliopanos et al. [2017] Koliopanos, F., Vasilopoulos, G., Godet, O., Bachetti, M., Webb, N. A., Barret, D., Dec. 2017. ULX spectra revisited: Accreting, highly magnetized neutron stars as the engines of ultraluminous X-ray sources. A&A 608, A47.
  * Kong and Di Stefano [2003] Kong, A. K. H., Di Stefano, R., Jun. 2003. A Luminous Recurrent Supersoft X-Ray Source in NGC 300. ApJL 590 (1), L13–L16.
  * Kong et al. [2016] Kong, A. K. H., Hu, C.-P., Lin, L. C.-C., Li, K. L., Jin, R., Liu, C. Y., Yen, D. C.-C., Oct. 2016. A possible 55-d X-ray period of the ultraluminous accreting pulsar M82 X-2. MNRAS 461, 4395–4399.
  * Kong et al. [2022] Kong, L.-D., Zhang, S., Zhang, S.-N., Ji, L., Doroshenko, V., Santangelo, A., Chen, Y.-P., Lu, F.-J., Ge, M.-Y., Wang, P.-J., Tao, L., Qu, J.-L., Li, T.-P., Liu, C.-Z., Liao, J.-Y., Chang, Z., Peng, J.-Q., Shui, Q.-C., Jul. 2022. Insight-HXMT Discovery of the Highest-energy CRSF from the First Galactic Ultraluminous X-Ray Pulsar Swift J0243.6+6124. ApjL 933 (1), L3.
  * Körding et al. [2005] Körding, E., Colbert, E., Falcke, H., Jun. 2005. A radio monitoring survey of ultra-luminous X-ray sources. A&A 436 (2), 427–436.
  * Körding et al. [2002] Körding, E., Falcke, H., Markoff, S., Jan. 2002. Population X: Are the super-Eddington X-ray sources beamed jets in microblazars or intermediate mass black holes? A&A 382, L13–L16.
  * Kosec et al. [2018a] Kosec, P., Pinto, C., Fabian, A. C., Walton, D. J., Feb. 2018a. Searching for outflows in ultraluminous X-ray sources through high-resolution X-ray spectroscopy. MNRAS 473 (4), 5680–5697.
  * Kosec et al. [2021] Kosec, P., Pinto, C., Reynolds, C. S., Guainazzi, M., Kara, E., Walton, D. J., Fabian, A. C., Parker, M. L., Valtchanov, I., Dec. 2021\. Ionized emission and absorption in a large sample of ultraluminous X-ray sources. MNRAS 508 (3), 3569–3588.
  * Kosec et al. [2018b] Kosec, P., Pinto, C., Walton, D. J., Fabian, A. C., Bachetti, M., Brightman, M., Fürst, F., Grefenstette, B. W., Sep. 2018b. Evidence for a variable Ultrafast Outflow in the newly discovered Ultraluminous Pulsar NGC 300 ULX-1. MNRAS 479 (3), 3978–3986.
  * Kotani et al. [1994] Kotani, T., Kawai, N., Aoki, T., Doty, J., Matsuoka, M., Mitsuda, K., Nagase, F., Ricker, G., White, N. E., Aug. 1994. Discovery of the Double Doppler-Shifted Emission-Line Systems in the X-Ray Spectrum of SS 433\. PASJ 46, L147–L150.
  * Kotko and Lasota [2012] Kotko, I., Lasota, J. P., Sep. 2012. The viscosity parameter $\alpha$ and the properties of accretion disc outbursts in close binaries. A&A 545, A115.
  * Kotze and Charles [2012] Kotze, M. M., Charles, P. A., Feb. 2012. Characterizing X-ray binary long-term variability. MNRAS 420 (2), 1575–1589.
  * Kovlakas et al. [2022] Kovlakas, K., Fragos, T., Schaerer, D., Mesinger, A., Jul. 2022. The ionizing and heating power of ultraluminous X-ray sources under the geometrical beaming model. arXiv e-prints, arXiv:2207.09331.
  * Kovlakas et al. [2021] Kovlakas, K., Zezas, A., Andrews, J. J., Basu-Zych, A., Fragos, T., Hornschemeier, A., Kouroumpatzakis, K., Lehmer, B., Ptak, A., Sep. 2021\. The Heraklion Extragalactic Catalogue (HECATE): a value-added galaxy catalogue for multimessenger astrophysics. MNRAS 506 (2), 1896–1915.
  * Kovlakas et al. [2020] Kovlakas, K., Zezas, A., Andrews, J. J., Basu-Zych, A., Fragos, T., Hornschemeier, A., Lehmer, B., Ptak, A., Nov. 2020. A census of ultraluminous X-ray sources in the local Universe. MNRAS 498 (4), 4790–4810.
  * Kozai [1962] Kozai, Y., Nov. 1962. Secular perturbations of asteroids with high inclination and eccentricity. AJ 67, 591–598.
  * Kozlowski et al. [1978] Kozlowski, M., Jaroszynski, M., Abramowicz, M. A., Feb. 1978. The analytic theory of fluid disks orbiting the Kerr black hole. A&A 63 (1-2), 209–220.
  * Kretschmar et al. [2000] Kretschmar, P., Kreykenbohm, I., Wilms, J., Staubert, R., Heindl, W. A., Gruber, D. E., Rothschild, R. E., Apr. 2000. Disappearing pulses in Vela X-1. In: McConnell, M. L., Ryan, J. M. (Eds.), The Fifth Compton Symposium. Vol. 510 of American Institute of Physics Conference Series. pp. 163–167.
  * Kuranov et al. [2020] Kuranov, A. G., Postnov, K. A., Yungelson, L. R., Oct. 2020. Population Synthesis of Ultraluminous X-ray Sources with Magnetized Neutron Stars. Astronomy Letters 46 (10), 658–676.
  * Lai [2003] Lai, D., Jul. 2003. Warping of Accretion Disks with Magnetically Driven Outflows: A Possible Origin for Jet Precession. ApJL 591 (2), L119–L122.
  * Lander and Jones [2009] Lander, S. K., Jones, D. I., Jun. 2009. Magnetic fields in axisymmetric neutron stars. MNRAS 395 (4), 2162–2176.
  * Lang et al. [2007] Lang, C. C., Kaaret, P., Corbel, S., Mercer, A., Sep. 2007. A Radio Nebula Surrounding the Ultraluminous X-Ray Source in NGC 5408. ApJ 666 (1), 79–85.
  * Lasota [2001] Lasota, J.-P., Jun. 2001. The disc instability model of dwarf novae and low-mass X-ray binary transients. New Astronomy Reviews 45, 449–508.
  * Lasota [2016] Lasota, J.-P., 2016. Black Hole Accretion Discs. In: Bambi, C. (Ed.), Astrophysics of Black Holes: From Fundamental Aspects to Latest Developments. Vol. 440 of Astrophysics and Space Science Library. p. 1.
  * Lasota et al. [2015] Lasota, J.-P., King, A. R., Dubus, G., Mar. 2015. X-ray Transients: Hyper- or Hypo-Luminous? ApJL 801, L4.
  * Lasota et al. [2016] Lasota, J.-P., Vieira, R. S. S., Sa̧dowski, A., Narayan, R., Abramowicz, M. A., Mar. 2016. The slimming effect of advection on black-hole accretion flows. A&A 587, A13.
  * Lau et al. [2019] Lau, R. M., Heida, M., Walton, D. J., Kasliwal, M. M., Adams, S. M., Cody, A. M., De, K., Gehrz, R. D., Fürst, F., Jencson, J. E., Kennea, J. A., Masci, F., Jun. 2019. Uncovering Red and Dusty Ultraluminous X-Ray Sources with Spitzer. ApJ 878 (1), 71.
  * Lehmer et al. [2021] Lehmer, B. D., Eufrasio, R. T., Basu-Zych, A., Doore, K., Fragos, T., Garofali, K., Kovlakas, K., Williams, B. F., Zezas, A., Santana-Silva, L., Jan. 2021. The Metallicity Dependence of the High-mass X-Ray Binary Luminosity Function. ApJ 907 (1), 17.
  * Lewin et al. [1997] Lewin, W. H. G., van Paradijs, J., van den Heuvel, E. P. J., 1997. X-ray Binaries.
  * Li et al. [2013] Li, J., Ostriker, J., Sunyaev, R., Apr. 2013. Rotating Accretion Flows: From Infinity to the Black Hole. ApJ 767 (2), 105.
  * Licquia and Newman [2015] Licquia, T. C., Newman, J. A., Jun. 2015. Improved Estimates of the Milky Way’s Stellar Mass and Star Formation Rate from Hierarchical Bayesian Meta-Analysis. ApJ 806, 96.
  * Lidov [1962] Lidov, M. L., Oct. 1962. The evolution of orbits of artificial satellites of planets under the action of gravitational perturbations of external bodies. PLANSS 9 (10), 719–759.
  * Lin et al. [2013] Lin, D., Irwin, J. A., Webb, N. A., Barret, D., Remillard, R. A., Dec. 2013. Discovery of a Highly Variable Dipping Ultraluminous X-Ray Source in M94. ApJ 779 (2), 149.
  * Linden et al. [2010] Linden, T., Kalogera, V., Sepinsky, J. F., Prestwich, A., Zezas, A., Gallagher, J. S., Dec. 2010. The Effect of Starburst Metallicity on Bright X-ray Binary Formation Pathways. ApJ 725, 1984–1994.
  * Lipunov and Shakura [1980] Lipunov, V. M., Shakura, N. I., Feb. 1980. Interaction of the accretion disk with the magnetic field of a neutron star. Soviet Astronomy Letters 6, 14–17.
  * Liu et al. [2007] Liu, J.-F., Bregman, J., Miller, J., Kaaret, P., May 2007. Optical Studies of the Ultraluminous X-Ray Source NGC 1313 X-2. ApJ 661 (1), 165–172.
  * Liu et al. [2013] Liu, J.-F., Bregman, J. N., Bai, Y., Justham, S., Crowther, P., Nov. 2013\. Puzzling accretion onto a black hole in the ultraluminous X-ray source M 101 ULX-1. Nature 503 (7477), 500–503.
  * López et al. [2017] López, K. M., Heida, M., Jonker, P. G., Torres, M. A. P., Roberts, T. P., Walton, D. J., Moon, D. S., Harrison, F. A., Jul. 2017\. A systematic search for near-infrared counterparts of nearby ultraluminous X-ray sources (II). MNRAS 469 (1), 671–682.
  * López et al. [2020] López, K. M., Heida, M., Jonker, P. G., Torres, M. A. P., Roberts, T. P., Walton, D. J., Moon, D. S., Harrison, F. A., Sep. 2020\. NIR counterparts to ULXs (III): completing the photometric survey and selected spectroscopic results. MNRAS 497 (1), 917–932.
  * Luangtip et al. [2016] Luangtip, W., Roberts, T. P., Done, C., Aug. 2016. The X-ray spectral evolution of the ultraluminous X-ray source Holmberg IX X-1. MNRAS 460 (4), 4417–4432.
  * Luangtip et al. [2015] Luangtip, W., Roberts, T. P., Mineo, S., Lehmer, B. D., Alexander, D. M., Jackson, F. E., Goulding, A. D., Fischer, J. L., Jan. 2015. A deficit of ultraluminous X-ray sources in luminous infrared galaxies. MNRAS 446, 470–492.
  * Lutovinov and Tsygankov [2009] Lutovinov, A. A., Tsygankov, S. S., Jul. 2009. Timing characteristics of the hard X-ray emission from bright X-ray pulsars based on INTEGRAL data. Astronomy Letters 35 (7), 433–456.
  * Lyubarskii [1997] Lyubarskii, Y. E., Dec. 1997. Flicker noise in accretion discs. MNRAS 292 (3), 679–685.
  * Maccarone et al. [2007] Maccarone, T. J., Kundu, A., Zepf, S. E., Rhode, K. L., Jan. 2007. A black hole in a globular cluster. Nature 445 (7124), 183–185.
  * Maccarone et al. [2011] Maccarone, T. J., Kundu, A., Zepf, S. E., Rhode, K. L., Jan. 2011. A new globular cluster black hole in NGC 4472. MNRAS 410 (3), 1655–1659.
  * Madhusudhan et al. [2008] Madhusudhan, N., Rappaport, S., Podsiadlowski, P., Nelson, L., Dec. 2008\. Models for the Observable System Parameters of Ultraluminous X-Ray Sources. ApJ 688, 1235–1249.
  * Mainieri et al. [2010] Mainieri, V., Vignali, C., Merloni, A., Civano, F., Puccetti, S., Brusa, M., Gilli, R., Bolzonella, M., Comastri, A., Zamorani, G., Aller, M., Carollo, M., Scarlata, C., Elvis, M., Aldcroft, T. L., Cappelluti, N., Fabbiano, G., Finoguenov, A., Fiore, F., Fruscione, A., Koekemoer, A. M., Contini, T., Kneib, J.-P., Le Fèvre, O., Lilly, S., Renzini, A., Scodeggio, M., Bardelli, S., Bongiorno, A., Caputi, K., Coppa, G., Cucciati, O., de la Torre, S., de Ravel, L., Franzetti, P., Garilli, B., Iovino, A., Kampczyk, P., Knobel, C., Kovač, K., Lamareille, F., Le Borgne, J.-F., Le Brun, V., Maier, C., Mignoli, M., Pello, R., Peng, Y., Perez Montero, E., Ricciardelli, E., Silverman, J. D., Tanaka, M., Tasca, L., Tresse, L., Vergani, D., Zucca, E., Capak, P., Ilbert, O., Impey, C., Salvato, M., Scoville, N., Taniguchi, Y., Trump, J., May 2010. Ultraluminous X-ray sources out to z ~ 0.3 in the COSMOS field. A&A 514, A85.
  * Mapelli et al. [2013] Mapelli, M., Annibali, F., Zampieri, L., Soria, R., Nov. 2013. A disrupted bulgeless satellite galaxy as counterpart of the ultraluminous X-ray source ESO 243-49 HLX-1. A&A 559, A124.
  * Mapelli et al. [2009] Mapelli, M., Colpi, M., Zampieri, L., May 2009. Low metallicity and ultra-luminous X-ray sources in the Cartwheel galaxy. MNRAS 395, L71–L75.
  * Mapelli et al. [2010] Mapelli, M., Ripamonti, E., Zampieri, L., Colpi, M., Bressan, A., Oct. 2010. Ultra-luminous X-ray sources and remnants of massive metal-poor stars. MNRAS 408, 234–253.
  * Marchant et al. [2017] Marchant, P., Langer, N., Podsiadlowski, P., Tauris, T. M., de Mink, S., Mandel, I., Moriya, T. J., Aug. 2017. Ultra-luminous X-ray sources and neutron-star-black-hole mergers from very massive close binaries at low metallicity. A&A 604, A55.
  * Margon et al. [1979] Margon, B., Ford, H. C., Grandi, S. A., Stone, R. P. S., Oct. 1979. Enormous periodic Doppler shifts in SS433. ApJL 233, L63–L68.
  * Marshall et al. [2013] Marshall, H. L., Canizares, C. R., Hillwig, T., Mioduszewski, A., Rupen, M., Schulz, N. S., Nowak, M., Heinz, S., Sep. 2013. Multiwavelength Observations of the SS 433 Jets. ApJ 775 (1), 75.
  * Martin et al. [2014] Martin, R. G., Nixon, C., Lubow, S. H., Armitage, P. J., Price, D. J., Doğan, S., King, A., Sep. 2014. The Kozai-Lidov Mechanism in Hydrodynamical Disks. ApJL 792 (2), L33.
  * Mauerhan et al. [2010] Mauerhan, J. C., Muno, M. P., Morris, M. R., Stolovy, S. R., Cotera, A., Feb. 2010. Near-infrared Counterparts to Chandra X-ray Sources Toward the Galactic Center. II. Discovery of Wolf-Rayet Stars and O Supergiants. ApJ 710 (1), 706–728.
  * McClintock et al. [2006] McClintock, J. E., Shafee, R., Narayan, R., Remillard, R. A., Davis, S. W., Li, L.-X., Nov. 2006. The Spin of the Near-Extreme Kerr Black Hole GRS 1915+105. ApJ 652 (1), 518–539.
  * McKinney and Gammie [2002] McKinney, J. C., Gammie, C. F., Jul. 2002. Numerical Models of Viscous Accretion Flows near Black Holes. ApJ 573 (2), 728–737.
  * Medvedev and Fabrika [2010] Medvedev, A., Fabrika, S., Feb. 2010. Evidence of supercritical disc funnel radiation in X-ray spectra of SS 433. MNRAS 402 (1), 479–491.
  * Merloni et al. [2003] Merloni, A., Heinz, S., di Matteo, T., Nov. 2003. A Fundamental Plane of black hole activity. MNRAS 345 (4), 1057–1076.
  * Mezcua et al. [2013a] Mezcua, M., Farrell, S. A., Gladstone, J. C., Lobanov, A. P., Dec. 2013a. Milliarcsec-scale radio emission of ultraluminous X-ray sources: steady jet emission from an intermediate-mass black hole? MNRAS 436 (2), 1546–1554.
  * Mezcua and Lobanov [2011] Mezcua, M., Lobanov, A. P., May 2011. Compact radio emission in Ultraluminous X-ray sources. Astronomische Nachrichten 332 (4), 379.
  * Mezcua et al. [2015] Mezcua, M., Roberts, T. P., Lobanov, A. P., Sutton, A. D., Apr. 2015. The powerful jet of an off-nuclear intermediate-mass black hole in the spiral galaxy NGC 2276. MNRAS 448 (2), 1893–1899.
  * Mezcua et al. [2013b] Mezcua, M., Roberts, T. P., Sutton, A. D., Lobanov, A. P., Dec. 2013b. Radio observations of extreme ULXs: revealing the most powerful ULX radio nebula ever or the jet of an intermediate-mass black hole? MNRAS 436 (4), 3128–3134.
  * Middleton et al. [2019a] Middleton, M. J., Brightman, M., Pintore, F., Bachetti, M., Fabian, A. C., Fürst, F., Walton, D. J., Jun. 2019a. On the magnetic field in M51 ULX-8. MNRAS 486 (1), 2–9.
  * Middleton et al. [2018] Middleton, M. J., Fragile, P. C., Bachetti, M., Brightman, M., Jiang, Y. F., Ho, W. C. G., Roberts, T. P., Ingram, A. R., Dauser, T., Pinto, C., Walton, D. J., Fuerst, F., Fabian, A. C., Gehrels, N., Mar 2018. Lense-Thirring precession in ULXs as a possible means to constrain the neutron star equation of state. MNRAS 475 (1), 154–166.
  * Middleton et al. [2019b] Middleton, M. J., Fragile, P. C., Ingram, A., Roberts, T. P., Oct 2019b. The Lense-Thirring timing-accretion plane for ULXs. MNRAS 489 (1), 282–296.
  * Middleton et al. [2015a] Middleton, M. J., Heil, L., Pintore, F., Walton, D. J., Roberts, T. P., Mar. 2015a. A spectral-timing model for ULXs in the supercritical regime. MNRAS 447, 3243–3263.
  * Middleton et al. [2015b] Middleton, M. J., Heil, L., Pintore, F., Walton, D. J., Roberts, T. P., Mar. 2015b. A spectral-timing model for ULXs in the supercritical regime. MNRAS 447 (4), 3243–3263.
  * Middleton et al. [2021a] Middleton, M. J., Higginbottom, N., Knigge, C., Khan, N., Wiktorowicz, G., Oct. 2021a. Thermally driven winds in ULXs. MNRAS.
  * Middleton and King [2016] Middleton, M. J., King, A., Oct. 2016. Geometrical beaming of stellar mass ULXs. MNRAS 462 (1), L71–L74.
  * Middleton and King [2017] Middleton, M. J., King, A., Sep. 2017. Predicting ultraluminous X-ray source demographics from geometrical beaming. MNRAS 470 (1), L69–L71.
  * Middleton et al. [2013] Middleton, M. J., Miller-Jones, J. C. A., Markoff, S., Fender, R., Henze, M., Hurley-Walker, N., Scaife, A. M. M., Roberts, T. P., Walton, D., Carpenter, J., Macquart, J.-P., Bower, G. C., Gurwell, M., Pietsch, W., Haberl, F., Harris, J., Daniel, M., Miah, J., Done, C., Morgan, J. S., Dickinson, H., Charles, P., Burwitz, V., Della Valle, M., Freyberg, M., Greiner, J., Hernanz, M., Hartmann, D. H., Hatzidimitriou, D., Riffeser, A., Sala, G., Seitz, S., Reig, P., Rau, A., Orio, M., Titterington, D., Grainge, K., Jan. 2013. Bright radio emission from an ultraluminous stellar-mass microquasar in M 31\. Nature 493 (7431), 187–190.
  * Middleton et al. [2011] Middleton, M. J., Roberts, T. P., Done, C., Jackson, F. E., Feb. 2011. Challenging times: a re-analysis of NGC 5408 X-1. MNRAS 411 (1), 644–652.
  * Middleton et al. [2021b] Middleton, M. J., Walton, D. J., Alston, W., Dauser, T., Eikenberry, S., Jiang, Y. F., Fabian, A. C., Fuerst, F., Brightman, M., Marshall, H., Parker, M., Pinto, C., Harrison, F. A., Bachetti, M., Altamirano, D., Bird, A. J., Perez, G., Miller-Jones, J., Charles, P., Boggs, S., Christensen, F., Craig, W., Forster, K., Grefenstette, B., Hailey, C., Madsen, K., Stern, D., Zhang, W., Sep. 2021b. NuSTAR reveals the hidden nature of SS433. MNRAS 506 (1), 1045–1058.
  * Middleton et al. [2015c] Middleton, M. J., Walton, D. J., Fabian, A., Roberts, T. P., Heil, L., Pinto, C., Anderson, G., Sutton, A., Dec. 2015c. Diagnosing the accretion flow in ultraluminous X-ray sources using soft X-ray atomic features. MNRAS 454 (3), 3134–3142.
  * Middleton et al. [2015d] Middleton, M. J., Walton, D. J., Fabian, A., Roberts, T. P., Heil, L., Pinto, C., Anderson, G., Sutton, A., Dec. 2015d. Diagnosing the accretion flow in ultraluminous X-ray sources using soft X-ray atomic features. MNRAS 454, 3134–3142.
  * Middleton et al. [2014] Middleton, M. J., Walton, D. J., Roberts, T. P., Heil, L., Feb. 2014. Broad absorption features in wind-dominated ultraluminous X-ray sources? MNRAS 438 (1), L51–L55.
  * Miller [1995] Miller, B. W., Jun. 1995. The Optical Counterpart to the Extremely Luminous X-Ray Source near Holmberg IX: A Possible Supershell in a Tidal Tail. ApJL 446, L75.
  * Miller et al. [2004a] Miller, J. M., Fabian, A. C., Miller, M. C., Oct. 2004a. A Comparison of Intermediate-Mass Black Hole Candidate Ultraluminous X-Ray Sources and Stellar-Mass Black Holes. ApJL 614 (2), L117–L120.
  * Miller et al. [2004b] Miller, J. M., Fabian, A. C., Miller, M. C., Jun. 2004b. Revealing a Cool Accretion Disk in the Ultraluminous X-Ray Source M81 X-9 (Holmberg IX X-1): Evidence for an Intermediate-Mass Black Hole. ApJ 607 (2), 931–938.
  * Miller et al. [2004c] Miller, J. M., Fabian, A. C., Miller, M. C., Jun. 2004c. Revealing a Cool Accretion Disk in the Ultraluminous X-Ray Source M81 X-9 (Holmberg IX X-1): Evidence for an Intermediate-Mass Black Hole. ApJ 607 (2), 931–938.
  * Miller et al. [2013] Miller, J. M., Walton, D. J., King, A. L., Reynolds, M. T., Fabian, A. C., Miller, M. C., Reis, R. C., Oct. 2013. Revisiting Putative Cool Accretion Disks in Ultraluminous X-Ray Sources. ApJL 776 (2), L36.
  * Miller and Hamilton [2002] Miller, M. C., Hamilton, D. P., Feb. 2002. Production of intermediate-mass black holes in globular clusters. MNRAS 330, 232–240.
  * Miller-Jones et al. [2019] Miller-Jones, J. C. A., Tetarenko, A. J., Sivakoff, G. R., Middleton, M. J., Altamirano, D., Anderson, G. E., Belloni, T. M., Fender, R. P., Jonker, P. G., Körding, E. G., Krimm, H. A., Maitra, D., Markoff, S., Migliari, S., Mooley, K. P., Rupen, M. P., Russell, D. M., Russell, T. D., Sarazin, C. L., Soria, R., Tudose, V., Apr. 2019\. A rapidly changing jet orientation in the stellar-mass black-hole system V404 Cygni. Nature 569 (7756), 374–377.
  * Mineo et al. [2012] Mineo, S., Gilfanov, M., Sunyaev, R., Jan. 2012. X-ray emission from star-forming galaxies - I. High-mass X-ray binaries. MNRAS 419 (3), 2095–2115.
  * Mineshige et al. [1994] Mineshige, S., Hirano, A., Kitamoto, S., Yamada, T. T., Fukue, J., May 1994. Time-dependent Disk Accretion in X-Ray Nova MUSCAE 1991. ApJ 426, 308\.
  * Miniutti et al. [2020] Miniutti, G., Alexander, K. D., Bianchi, S., Chiaberge, M., Giustini, M., Laor, A., Read, A., Saxton, R., Uttley, P., Jan. 2020. Quasi-Periodic Eruptions (QPEs) in GSN 069. HST Proposal.
  * Miniutti et al. [2019] Miniutti, G., Saxton, R. D., Giustini, M., Alexander, K. D., Fender, R. P., Heywood, I., Monageng, I., Coriat, M., Tzioumis, A. K., Read, A. M., Knigge, C., Gandhi, P., Pretorius, M. L., Agís-González, B., Sep. 2019. Nine-hour X-ray quasi-periodic eruptions from a low-mass black hole galactic nucleus. NATURE 573 (7774), 381–384.
  * Mitsuda et al. [1984] Mitsuda, K., Inoue, H., Koyama, K., Makishima, K., Matsuoka, M., Ogawara, Y., Shibazaki, N., Suzuki, K., Tanaka, Y., Hirano, T., Jan. 1984. Energy spectra of low-mass binary X-ray sources observed from Tenma. PASJ 36, 741–759.
  * Mohamed and Podsiadlowski [2007] Mohamed, S., Podsiadlowski, P., Sep. 2007. Wind Roche-Lobe Overflow: a New Mass-Transfer Mode for Wide Binaries. In: Napiwotzki, R., Burleigh, M. R. (Eds.), 15th European Workshop on White Dwarfs. Vol. 372 of Astronomical Society of the Pacific Conference Series. p. 397.
  * Monard [2010] Monard, L. A. G., May 2010. Supernova 2010da in NGC 300. Central Bureau Electronic Telegrams 2289, 1.
  * Mondal et al. [2020] Mondal, S., Belczyński, K., Wiktorowicz, G., Lasota, J.-P., King, A. R., Jan. 2020. The connection between merging double compact objects and the ultraluminous X-ray sources. MNRAS 491 (2), 2747–2759.
  * Mondal et al. [2021] Mondal, S., Różańska, A., De Marco, B., Markowitz, A., Jul. 2021\. Evidence for Fe Kα line and soft X-ray lag in NGC 7456 ultraluminous X-ray source-1. MNRAS 505 (1), L106–L111.
  * Moon et al. [2011] Moon, D.-S., Harrison, F. A., Cenko, S. B., Shariff, J. A., Apr. 2011. Large Highly Ionized Nebulae Around Ultra-luminous X-ray Sources. ApJL 731 (2), L32.
  * Motch [2018] Motch, C., 2018. Optical Observations of Ultra-luminous X-ray Pulsars, presentation at “Ultra-luminous X-ray Pulsars”, 6 - 8 june 2018, European Space Astronomy Centre (ESAC), Villafranca del Castillo, Spain. Available at https://www.cosmos.esa.int/documents/1518557/1518574/motch.pdf/a08257a9-9b9b-b56f-63d1-067cd7ae8f8f.
  * Motch et al. [2014] Motch, C., Pakull, M. W., Soria, R., Grisé, F., Pietrzyński, G., Oct. 2014. A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source. Nature 514, 198–201.
  * Motta et al. [2017] Motta, S. E., Kajava, J. J. E., Sánchez-Fernández, C., Beardmore, A. P., Sanna, A., Page, K. L., Fender, R., Altamirano, D., Charles, P., Giustini, M., Knigge, C., Kuulkers, E., Oates, S., Osborne, J. P., Oct. 2017. Swift observations of V404 Cyg during the 2015 outburst: X-ray outflows from super-Eddington accretion. MNRAS 471 (2), 1797–1818.
  * Mukherjee et al. [2015] Mukherjee, E. S., Walton, D. J., Bachetti, M., Harrison, F. A., Barret, D., Bellm, E., Boggs, S. E., Christensen, F. E., Craig, W. W., Fabian, A. C., Fuerst, F., Grefenstette, B. W., Hailey, C. J., Madsen, K. K., Middleton, M. J., Miller, J. M., Rana, V., Stern, D., Zhang, W., Jul. 2015. A Hard X-Ray Study of the Ultraluminous X-Ray Source NGC 5204 X-1 with NuSTAR and XMM-Newton. ApJ 808 (1), 64.
  * Mushtukov and Tsygankov [2022] Mushtukov, A., Tsygankov, S., Apr. 2022. Accreting strongly magnetised neutron stars: X-ray Pulsars. arXiv e-prints, arXiv:2204.14185.
  * Mushtukov et al. [2019] Mushtukov, A. A., Ingram, A., Middleton, M., Nagirner, D. I., van der Klis, M., Mar. 2019. Timing properties of ULX pulsars: optically thick envelopes and outflows. MNRAS 484 (1), 687–697.
  * Mushtukov et al. [2020] Mushtukov, A. A., Portegies Zwart, S., Tsygankov, S. S., Nagirner, D. I., Poutanen, J., Nov. 2020. Pulsating ULXs: large pulsed fraction excludes strong beaming. arXiv e-prints, arXiv:2011.09710.
  * Mushtukov et al. [2017] Mushtukov, A. A., Suleimanov, V. F., Tsygankov, S. S., Ingram, A., May 2017\. Optically thick envelopes around ULXs powered by accreating neutron stars. MNRAS 467, 1202–1208.
  * Mushtukov et al. [2015a] Mushtukov, A. A., Suleimanov, V. F., Tsygankov, S. S., Poutanen, J., Dec. 2015a. On the maximum accretion luminosity of magnetized neutron stars: connecting X-ray pulsars and ultraluminous X-ray sources. MNRAS 454, 2539–2548.
  * Mushtukov et al. [2015b] Mushtukov, A. A., Suleimanov, V. F., Tsygankov, S. S., Poutanen, J., Feb. 2015b. The critical accretion luminosity for magnetized neutron stars. MNRAS 447, 1847–1856.
  * Nandra et al. [2013] Nandra, K., Barret, D., Barcons, X., Fabian, A., den Herder, J.-W., Piro, L., Watson, M., Adami, C., Aird, J., Afonso, J. M., Alexander, D., Argiroffi, C., Amati, L., Arnaud, M., Atteia, J.-L., Audard, M., Badenes, C., Ballet, J., Ballo, L., Bamba, A., Bhardwaj, A., Stefano Battistelli, E., Becker, W., De Becker, M., Behar, E., Bianchi, S., Biffi, V., Bîrzan, L., Bocchino, F., Bogdanov, S., Boirin, L., Boller, T., Borgani, S., Borm, K., Bouché, N., Bourdin, H., Bower, R., Braito, V., Branchini, E., Branduardi-Raymont, G., Bregman, J., Brenneman, L., Brightman, M., Brüggen, M., Buchner, J., Bulbul, E., Brusa, M., Bursa, M., Caccianiga, A., Cackett, E., Campana, S., Cappelluti, N., Cappi, M., Carrera, F., Ceballos, M., Christensen, F., Chu, Y.-H., Churazov, E., Clerc, N., Corbel, S., Corral, A., Comastri, A., Costantini, E., Croston, J., Dadina, M., D’Ai, A., Decourchelle, A., Della Ceca, R., Dennerl, K., Dolag, K., Done, C., Dovciak, M., Drake, J., Eckert, D., Edge, A., Ettori, S., Ezoe, Y., Feigelson, E., Fender, R., Feruglio, C., Finoguenov, A., Fiore, F., Galeazzi, M., Gallagher, S., Gandhi, P., Gaspari, M., Gastaldello, F., Georgakakis, A., Georgantopoulos, I., Gilfanov, M., Gitti, M., Gladstone, R., Goosmann, R., Gosset, E., Grosso, N., Guedel, M., Guerrero, M., Haberl, F., Hardcastle, M., Heinz, S., Alonso Herrero, A., Hervé, A., Holmstrom, M., Iwasawa, K., Jonker, P., Kaastra, J., Kara, E., Karas, V., Kastner, J., King, A., Kosenko, D., Koutroumpa, D., Kraft, R., Kreykenbohm, I., Lallement, R., Lanzuisi, G., Lee, J., Lemoine-Goumard, M., Lobban, A., Lodato, G., Lovisari, L., Lotti, S., McCharthy, I., McNamara, B., Maggio, A., Maiolino, R., De Marco, B., de Martino, D., Mateos, S., Matt, G., Maughan, B., Mazzotta, P., Mendez, M., Merloni, A., Micela, G., Miceli, M., Mignani, R., Miller, J., Miniutti, G., Molendi, S., Montez, R., Moretti, A., Motch, C., Nazé, Y., Nevalainen, J., Nicastro, F., Nulsen, P., Ohashi, T., O’Brien, P., Osborne, J., Oskinova, L., Pacaud, F., Paerels, F., Page, M., Papadakis, I., Pareschi, G., Petre, R., Petrucci, P.-O., Piconcelli, E., Pillitteri, I., Pinto, C., de Plaa, J., Pointecouteau, E., Ponman, T., Ponti, G., Porquet, D., Pounds, K., Pratt, G., Predehl, P., Proga, D., Psaltis, D., Rafferty, D., Ramos-Ceja, M., Ranalli, P., Rasia, E., Rau, A., Rauw, G., Rea, N., Read, A., Reeves, J., Reiprich, T., Renaud, M., Reynolds, C., Risaliti, G., Rodriguez, J., Rodriguez Hidalgo, P., Roncarelli, M., Rosario, D., Rossetti, M., Rozanska, A., Rovilos, E., Salvaterra, R., Salvato, M., Di Salvo, T., Sanders, J., Sanz-Forcada, J., Schawinski, K., Schaye, J., Schwope, A., Sciortino, S., Severgnini, P., Shankar, F., Sijacki, D., Sim, S., Schmid, C., Smith, R., Steiner, A., Stelzer, B., Stewart, G., Strohmayer, T., Strüder, L., Sun, M., Takei, Y., Tatischeff, V., Tiengo, A., Tombesi, F., Trinchieri, G., Tsuru, T. G., Ud-Doula, A., Ursino, E., Valencic, L., Vanzella, E., Vaughan, S., Vignali, C., Vink, J., Vito, F., Volonteri, M., Wang, D., Webb, N., Willingale, R., Wilms, J., Wise, M., Worrall, D., Young, A., Zampieri, L., In’t Zand, J., Zane, S., Zezas, A., Zhang, Y., Zhuravleva, I., Jun. 2013. The Hot and Energetic Universe: A White Paper presenting the science theme motivating the Athena+ mission. arXiv e-prints, arXiv:1306.2307.
  * Narayan et al. [2017] Narayan, R., Sa̧dowski, A., Soria, R., Aug. 2017. Spectra of black hole accretion models of ultraluminous X-ray sources. MNRAS 469 (3), 2997–3014.
  * Neilsen et al. [2016] Neilsen, J., Rahoui, F., Homan, J., Buxton, M., May 2016. A Super-Eddington, Compton-thick Wind in GRO J1655-40? ApJ 822 (1), 20.
  * Nixon and Pringle [2020] Nixon, C. J., Pringle, J. E., Dec. 2020. Be Star Disks: Powered by a Nonzero Central Torque. ApJL 905 (2), L29.
  * Ohsuga and Mineshige [2011] Ohsuga, K., Mineshige, S., Jul. 2011. Global Structure of Three Distinct Accretion Flows and Outflows around Black Holes from Two-dimensional Radiation-magnetohydrodynamic Simulations. ApJ 736, 2.
  * Ohsuga and Mineshige [2014] Ohsuga, K., Mineshige, S., Sep. 2014. Outflow Launching Mechanisms. Space Science Reviews 183 (1-4), 353–369.
  * Ohsuga et al. [2005] Ohsuga, K., Mori, M., Nakamoto, T., Mineshige, S., Jul. 2005. Supercritical Accretion Flows around Black Holes: Two-dimensional, Radiation Pressure-dominated Disks with Photon Trapping. ApJ 628, 368–381.
  * Okuda [2002] Okuda, T., Apr. 2002. Super-Eddington Black-Hole Models for SS 433. PASJ 54, 253–266.
  * Okuda et al. [2009] Okuda, T., Lipunova, G. V., Molteni, D., Oct. 2009. The jets and disc of SS 433 at super-Eddington luminosities. MNRAS 398 (4), 1668–1677.
  * Olausen and Kaspi [2014] Olausen, S. A., Kaspi, V. M., May 2014. The McGill Magnetar Catalog. The Astrophysical Journal Supplement Series 212, 6.
  * Olejak et al. [2020] Olejak, A., Belczynski, K., Bulik, T., Sobolewska, M., Jun. 2020. Synthetic catalog of black holes in the Milky Way. A&A 638, A94.
  * Oskinova [2005] Oskinova, L. M., Aug. 2005. Evolution of X-ray emission from young massive star clusters. MNRAS 361 (2), 679–694.
  * Paczyński [1982] Paczyński, B., Jan. 1982. Thick Accretion Disks around Black Holes (Karl-Schwarzschild-Vorlesung 1981). Mitteilungen der Astronomischen Gesellschaft Hamburg 57, 27.
  * Paczynski [1992] Paczynski, B., Jul. 1992. GB 790305 as a Very Strongly Magnetized Neutron Star. AcA 42, 145–153.
  * Paczynsky and Wiita [1980] Paczynsky, B., Wiita, P. J., Aug. 1980. Thick accretion disks and supercritical luminosities. A&A 500, 203–211.
  * Pakull and Grisé [2008] Pakull, M. W., Grisé, F., May 2008. Ultraluminous X-ray Sources: Beambags and Optical Counterparts. In: Bandyopadhyay, R. M., Wachter, S., Gelino, D., Gelino, C. R. (Eds.), A Population Explosion: The Nature & Evolution of X-ray Binaries in Diverse Environments. Vol. 1010 of American Institute of Physics Conference Series. pp. 303–307.
  * Pakull et al. [2006] Pakull, M. W., Grisé, F., Motch, C., Jan 2006. Ultraluminous X-ray Sources: Bubbles and Optical Counterparts. In: Meurs, E. J. A., Fabbiano, G. (Eds.), Populations of High Energy Sources in Galaxies. Vol. 230 of IAU Symposium. pp. 293–297.
  * Pakull and Mirioni [2002] Pakull, M. W., Mirioni, L., Feb. 2002. Optical Counterparts of Ultraluminous X-Ray Sources. ArXiv Astrophysics e-prints.
  * Pakull et al. [2010] Pakull, M. W., Soria, R., Motch, C., Jul. 2010. A 300-parsec-long jet-inflated bubble around a powerful microquasar in the galaxy NGC 7793. Nature 466 (7303), 209–212.
  * Parfrey et al. [2016] Parfrey, K., Spitkovsky, A., Beloborodov, A. M., May 2016. Torque Enhancement, Spin Equilibrium, and Jet Power from Disk-Induced Opening of Pulsar Magnetic Fields. ApJ 822 (1), 33.
  * Parfrey and Tchekhovskoy [2017] Parfrey, K., Tchekhovskoy, A., Dec. 2017. General-relativistic Simulations of Four States of Accretion onto Millisecond Pulsars. ApJL 851, L34.
  * Pasham et al. [2015] Pasham, D. R., Cenko, S. B., Zoghbi, A., Mushotzky, R. F., Miller, J., Tombesi, F., Sep. 2015. Evidence for High-frequency QPOs with a 3:2 Frequency Ratio from a 5000 Solar Mass Black Hole. ApJL 811 (1), L11.
  * Pasham et al. [2019] Pasham, D. R., Remillard, R. A., Fragile, P. C., Franchini, A., Stone, N. C., Lodato, G., Homan, J., Chakrabarty, D., Baganoff, F. K., Steiner, J. F., Coughlin, E. R., Pasham, N. R., Feb. 2019. A loud quasi-periodic oscillation after a star is disrupted by a massive black hole. Science 363 (6426), 531–534.
  * Pasham and Strohmayer [2012] Pasham, D. R., Strohmayer, T. E., Jul. 2012. A Multi-epoch Timing and Spectral Study of the Ultraluminous X-Ray NGC 5408 X-1 with XMM-Newton. ApJ 753 (2), 139.
  * Pasham and Strohmayer [2013] Pasham, D. R., Strohmayer, T. E., Sep 2013. Can the 62 Day X-Ray Period of ULX M82 X-1 Be Due to a Precessing Accretion Disk? ApJL 774 (2), L16.
  * Pasham et al. [2014] Pasham, D. R., Strohmayer, T. E., Mushotzky, R. F., Sep. 2014. A 400-solar-mass black hole in the galaxy M82. Nature 513 (7516), 74–76.
  * Pérez-Ramírez et al. [2011] Pérez-Ramírez, D., Mezcua, M., Leon, S., Caballero-García, M. D., May 2011. A search for radio counterparts to Chandra ULX candidates. Astronomische Nachrichten 332 (4), 384.
  * Perlman et al. [2002] Perlman, E. S., Stocke, J. T., Carilli, C. L., Sugiho, M., Tashiro, M., Madejski, G., Wang, Q. D., Conway, J., Nov. 2002. The Apparent Host Galaxy of PKS 1413+135: Hubble Space Telescope, ASCA, and Very Long Baseline Array Observations. Aj 124 (5), 2401–2412.
  * Petterson [1977] Petterson, J. A., Dec. 1977. The 35 day cycle of the X-ray binary Hercules X-1. ApJ 218, 783–791.
  * Pfeiffer and Lai [2004] Pfeiffer, H. P., Lai, D., Apr. 2004. Warping and Precession of Accretion Disks around Magnetic Stars: Nonlinear Evolution. ApJ 604 (2), 766–774.
  * Pinto et al. [2017] Pinto, C., Alston, W., Soria, R., Middleton, M. J., Walton, D. J., Sutton, A. D., Fabian, A. C., Earnshaw, H., Urquhart, R., Kara, E., Roberts, T. P., Jul. 2017. From ultraluminous X-ray sources to ultraluminous supersoft sources: NGC 55 ULX, the missing link. MNRAS 468 (3), 2865–2883.
  * Pinto et al. [2020a] Pinto, C., Mehdipour, M., Walton, D. J., Middleton, M. J., Roberts, T. P., Fabian, A. C., Guainazzi, M., Soria, R., Kosec, P., Ness, J. U., Feb. 2020a. Thermal stability of winds driven by radiation pressure in super-Eddington accretion discs. MNRAS 491 (4), 5702–5716.
  * Pinto et al. [2016] Pinto, C., Middleton, M. J., Fabian, A. C., May 2016. Resolved atomic lines reveal outflows in two ultraluminous X-ray sources. Nature 533 (7601), 64–67.
  * Pinto et al. [2021] Pinto, C., Soria, R., Walton, D. J., D’Aì, A., Pintore, F., Kosec, P., Alston, W. N., Fuerst, F., Middleton, M. J., Roberts, T. P., Del Santo, M., Barret, D., Ambrosi, E., Robba, A., Earnshaw, H., Fabian, A. C., Aug. 2021. XMM-Newton campaign on the ultraluminous X-ray source NGC 247 ULX-1: outflows. MNRAS 505 (4), 5058–5074.
  * Pinto et al. [2020b] Pinto, C., Walton, D. J., Kara, E., Parker, M. L., Soria, R., Kosec, P., Middleton, M. J., Alston, W. N., Fabian, A. C., Guainazzi, M., Roberts, T. P., Fuerst, F., Earnshaw, H. P., Sathyaprakash, R., Barret, D., Mar. 2020b. XMM-Newton campaign on ultraluminous X-ray source NGC 1313 X-1: wind versus state variability. MNRAS 492 (4), 4646–4665.
  * Pintore et al. [2015] Pintore, F., Esposito, P., Zampieri, L., Motta, S., Wolter, A., Apr. 2015\. Spectral variability in Swift and Chandra observations of the ultraluminous source NGC 55 ULX1. MNRAS 448 (2), 1153–1161.
  * Pintore et al. [2021] Pintore, F., Motta, S., Pinto, C., Bernardini, M. G., Rodriguez-Castillo, G., Salvaterra, R., Israel, G. L., Esposito, P., Ambrosi, E., Salvaggio, C., Zampieri, L., Wolter, A., Mar. 2021. The rare X-ray flaring activity of the Ultraluminous X-ray source NGC 4559 X7. arXiv e-prints, arXiv:2103.14541.
  * Pintore et al. [2017] Pintore, F., Zampieri, L., Stella, L., Wolter, A., Mereghetti, S., Israel, G. L., Feb. 2017. Pulsator-like Spectra from Ultraluminous X-Ray Sources and the Search for More Ultraluminous Pulsars. ApJ 836 (1), 113.
  * Piro et al. [2017] Piro, A. L., Giacomazzo, B., Perna, R., Aug. 2017. The Fate of Neutron Star Binary Mergers. ApJL 844 (2), L19.
  * Podsiadlowski and Rappaport [2000] Podsiadlowski, P., Rappaport, S., Feb. 2000. Cygnus X-2: The Descendant of an Intermediate-Mass X-Ray Binary. ApJ 529, 946–951.
  * Ponti et al. [2012] Ponti, G., Fender, R. P., Begelman, M. C., Dunn, R. J. H., Neilsen, J., Coriat, M., May 2012. Ubiquitous equatorial accretion disc winds in black hole soft states. MNRAS 422 (1), L11–L15.
  * Popov [2016] Popov, S. B., Jan 2016. Origins of magnetars in binary systems. Astronomical and Astrophysical Transactions 29, 183–192.
  * Popov [2022] Popov, S. B., Jan. 2022. High magnetic field neutron stars and magnetars in binary systems. arXiv e-prints, arXiv:2201.07507.
  * Portegies Zwart and McMillan [2002] Portegies Zwart, S. F., McMillan, S. L. W., Sep. 2002. The Runaway Growth of Intermediate-Mass Black Holes in Dense Star Clusters. ApJ 576 (2), 899–907.
  * Pottschmidt et al. [2016] Pottschmidt, K., Ballhausen, R., Wilms, J., Zezas, A., Fuerst, F., Nowak, M. A., Grinberg, V., Kuehnel, M., Kretschmar, P., Tomsick, J. A., Antoniou, V., Kennea, J., Hong, J., Haberl, F., Maccarone, T., Hornschemeier, A., Ptak, A., Yukita, M., Wik, D., Lehmer, B., Fornasini, F., Bodaghee, A., McBride, V., Aug. 2016. NuSTAR Observations of SMC X-3. The Astronomer’s Telegram 9404, 1.
  * Poutanen et al. [2007] Poutanen, J., Lipunova, G., Fabrika, S., Butkevich, A. G., Abolmasov, P., May 2007. Supercritically accreting stellar mass black holes as ultraluminous X-ray sources. MNRAS 377, 1187–1194.
  * Prestwich et al. [2013] Prestwich, A. H., Tsantaki, M., Zezas, A., Jackson, F., Roberts, T. P., Foltz, R., Linden, T., Kalogera, V., Jun. 2013. Ultra-luminous X-Ray Sources in the Most Metal Poor Galaxies. ApJ 769, 92.
  * Pringle [1975] Pringle, J. E., Mar. 1975. Period changes in eruptive binaries. MNRAS 170, 633–642.
  * Pringle [1996] Pringle, J. E., Jul 1996. Self-induced warping of accretion discs. MNRAS 281 (1), 357–361.
  * Qiu and Feng [2021] Qiu, Y., Feng, H., Jan. 2021. Linking Soft Excess in Ultraluminous X-Ray Sources with Optically Thick Wind Driven by Supercritical Accretion. ApJ 906 (1), 36.
  * Ramsey et al. [2006] Ramsey, C. J., Williams, R. M., Gruendl, R. A., Chen, C. H. R., Chu, Y.-H., Wang, Q. D., Apr. 2006. An Optical Study of Stellar and Interstellar Environments of Seven Luminous and Ultraluminous X-Ray Sources. ApJ 641 (1), 241–251.
  * Ransom [2001] Ransom, S. M., Jan. 2001. New search techniques for binary pulsars. Ph.D. thesis, Harvard University.
  * Ransom et al. [2002] Ransom, S. M., Eikenberry, S. S., Middleditch, J., Sep. 2002. Fourier Techniques for Very Long Astrophysical Time-Series Analysis. AJ 124 (3), 1788–1809.
  * Rao et al. [2010] Rao, F., Feng, H., Kaaret, P., Oct. 2010. Detection of Strong Short-term Variability in NGC 6946 X-1. ApJ 722 (1), 620–624.
  * Rappaport et al. [2005] Rappaport, S. A., Podsiadlowski, P., Pfahl, E., Jan. 2005. Stellar-mass black hole binaries as ultraluminous X-ray sources. MNRAS 356, 401–414.
  * Ray et al. [2019] Ray, P. S., Guillot, S., Ho, W. C. G., Kerr, M., Enoto, T., Gendreau, K. C., Arzoumanian, Z., Altamirano, D., Bogdanov, S., Campion, R., Chakrabarty, D., Deneva, J. S., Jaisawal, G. K., Kozon, R., Malacaria, C., Strohmayer, T. E., Wolff, M. T., Jul. 2019. Anti-glitches in the Ultraluminous Accreting Pulsar NGC 300 ULX-1 Observed with NICER. ApJ 879 (2), 130.
  * Reig et al. [2020] Reig, P., Fabregat, J., Alfonso-Garzón, J., Aug. 2020. Optical counterpart to Swift J0243.6+6124. A&A 640, A35.
  * Revnivtsev et al. [1999] Revnivtsev, M., Gilfanov, M., Churazov, E., Jul. 1999. The frequency resolved spectroscopy of CYG X-1: fast variability of the Fe K_$\alpha$ line. A&A 347, L23–L26.
  * Revnivtsev et al. [2002] Revnivtsev, M., Gilfanov, M., Churazov, E., Sunyaev, R., Sep. 2002. Super-Eddington outburst of V4641 Sgr. A&A 391, 1013–1022.
  * Revnivtsev and Mereghetti [2016] Revnivtsev, M., Mereghetti, S., 2016. Magnetic Fields of Neutron Stars in X-Ray Binaries. Vol. 54. p. 299.
  * Ritter [1988] Ritter, H., Aug. 1988. Turning on and off mass transfer in cataclysmic binaries. A&A 202, 93–100.
  * Ritter and King [2001] Ritter, H., King, A. R., Jan. 2001. On the Spin-Up of Neutron Stars to Millisecond Pulsars in Long-Period Binaries. In: Podsiadlowski, P., Rappaport, S., King, A. R., D’Antona, F., Burderi, L. (Eds.), Evolution of Binary and Multiple Star Systems. Vol. 229 of Astronomical Society of the Pacific Conference Series. p. 423.
  * Robba et al. [2021] Robba, A., Pinto, C., Walton, D. J., Soria, R., Kosec, P., Pintore, F., Roberts, T. P., Alston, W. N., Middleton, M., Cusumano, G., Earnshaw, H. P., Fuerst, F., Sathyaprakash, R., Kyritsis, E., Fabian, A. C., Jun. 2021. Broadband X-ray spectral variability of the pulsing ULX NGC 1313 X-2. arXiv e-prints, arXiv:2106.04501.
  * Roberts et al. [2012] Roberts, T. P., Fabbiano, G., Luo, B., Kim, D. W., Strader, J., Middleton, M. J., Brodie, J. P., Fragos, T., Gallagher, J. S., Kalogera, V., King, A. R., Zezas, A., Dec. 2012. A Variable Ultraluminous X-Ray Source in a Globular Cluster in NGC 4649. ApJ 760 (2), 135\.
  * Roberts et al. [2011] Roberts, T. P., Gladstone, J. C., Goulding, A. D., Swinbank, A. M., Ward, M. J., Goad, M. R., Levan, A. J., May 2011. (No) dynamical constraints on the mass of the black hole in two ULXs. Astronomische Nachrichten 332 (4), 398.
  * Roberts et al. [2003] Roberts, T. P., Goad, M. R., Ward, M. J., Warwick, R. S., Jul. 2003. The unusual supernova remnant surrounding the ultraluminous X-ray source IC 342 X-1. MNRAS 342 (3), 709–714.
  * Roberts et al. [2001] Roberts, T. P., Goad, M. R., Ward, M. J., Warwick, R. S., O’Brien, P. T., Lira, P., Hands, A. D. P., Aug. 2001. The identification of an optical counterpart to the super-Eddington X-ray source NGC 5204 X-1. MNRAS 325 (2), L7–L11.
  * Roberts et al. [2006] Roberts, T. P., Kilgard, R. E., Warwick, R. S., Goad, M. R., Ward, M. J., Oct. 2006. Chandra monitoring observations of the ultraluminous X-ray source NGC 5204 X-1. MNRAS 371 (4), 1877–1890.
  * Roberts et al. [2008] Roberts, T. P., Levan, A. J., Goad, M. R., Jun. 2008. New Hubble Space Telescope imaging of the counterparts to six ultraluminous X-ray sources. MNRAS 387 (1), 73–78.
  * Roberts et al. [2005] Roberts, T. P., Warwick, R. S., Ward, M. J., Goad, M. R., Jenkins, L. P., Mar. 2005. XMM-Newton EPIC observations of the ultraluminous X-ray source NGC 5204 X-1. MNRAS 357 (4), 1363–1369.
  * Rodríguez Castillo et al. [2020] Rodríguez Castillo, G. A., Israel, G. L., Belfiore, A., Bernardini, F., Esposito, P., Pintore, F., De Luca, A., Papitto, A., Stella, L., Tiengo, A., Zampieri, L., Bachetti, M., Brightman, M., Casella, P., D’Agostino, D., Dall’Osso, S., Earnshaw, H. P., Fürst, F., Haberl, F., Harrison, F. A., Mapelli, M., Marelli, M., Middleton, M., Pinto, C., Roberts, T. P., Salvaterra, R., Turolla, R., Walton, D. J., Wolter, A., May 2020. Discovery of a 2.8 s Pulsar in a 2 Day Orbit High-mass X-Ray Binary Powering the Ultraluminous X-Ray Source ULX-7 in M51. ApJ 895 (1), 60.
  * Rosen et al. [2016] Rosen, S. R., Webb, N. A., Watson, M. G., Ballet, J., Barret, D., Braito, V., Carrera, F. J., Ceballos, M. T., Coriat, M., Della Ceca, R., Denkinson, G., Esquej, P., Farrell, S. A., Freyberg, M., Grisé, F., Guillout, P., Heil, L., Koliopanos, F., Law-Green, D., Lamer, G., Lin, D., Martino, R., Michel, L., Motch, C., Nebot Gomez-Moran, A., Page, C. G., Page, K., Page, M., Pakull, M. W., Pye, J., Read, A., Rodriguez, P., Sakano, M., Saxton, R., Schwope, A., Scott, A. E., Sturm, R., Traulsen, I., Yershov, V., Zolotukhin, I., May 2016. The XMM-Newton serendipitous survey. VII. The third XMM-Newton serendipitous source catalogue. A&A 590, A1.
  * Russell et al. [2011] Russell, D. M., Yang, Y. J., Gladstone, J. C., Wiersema, K., Roberts, T. P., May 2011. New observations of ULX supershells, and their implications. Astronomische Nachrichten 332 (4), 371.
  * Sadowski [2011] Sadowski, A., Aug. 2011. Slim accretion disks around black holes. arXiv e-prints, arXiv:1108.0396.
  * Sakurai et al. [2016] Sakurai, Y., Inayoshi, K., Haiman, Z., Oct. 2016. Hyper-Eddington mass accretion on to a black hole with super-Eddington luminosity. MNRAS 461 (4), 4496–4504.
  * Sathyaprakash et al. [2022] Sathyaprakash, R., Roberts, T. P., Grisé, F., Kaaret, P., Ambrosi, E., Done, C., Gladstone, J. C., Kajava, J. J. E., Soria, R., Zampieri, L., Apr. 2022. A multi-wavelength view of distinct accretion regimes in the pulsating ultraluminous X-ray source NGC 1313 X-2. MNRAS 511 (4), 5346–5362.
  * Sathyaprakash et al. [2019a] Sathyaprakash, R., Roberts, T. P., Siwek, M. M., Oct. 2019a. Observational limits on the X-ray emission from the bubble nebula surrounding Ho IX X-1. MNRAS 488 (4), 4614–4622.
  * Sathyaprakash et al. [2019b] Sathyaprakash, R., Roberts, T. P., Walton, D. J., Fuerst, F., Bachetti, M., Pinto, C., Alston, W. N., Earnshaw, H. P., Fabian, A. C., Middleton, M. J., Soria, R., Sep 2019b. The discovery of weak coherent pulsations in the ultraluminous X-ray source NGC 1313 X-2. MNRAS 488 (1), L35–L40.
  * Sazonov et al. [1997] Sazonov, S. Y., Sunyaev, R. A., Lund, N., May 1997. Super-Eddington x-ray luminosity of the bursting pulsar GRO J1744-28: WATCH/Granat observations. Astronomy Letters 23 (3), 286–292.
  * Sa̧dowski [2009] Sa̧dowski, A., Aug. 2009. Slim Disks Around Kerr Black Holes Revisited. ApJS 183 (2), 171–178.
  * Sa̧dowski et al. [2011] Sa̧dowski, A., Abramowicz, M., Bursa, M., Kluźniak, W., Lasota, J. P., Różańska, A., Mar. 2011. Relativistic slim disks with vertical structure. A&A 527, A17.
  * Sa̧dowski and Narayan [2015] Sa̧dowski, A., Narayan, R., Nov. 2015. Powerful radiative jets in supercritical accretion discs around non-spinning black holes. MNRAS 453, 3213–3221.
  * Sa̧dowski et al. [2015] Sa̧dowski, A., Narayan, R., Tchekhovskoy, A., Abarca, D., Zhu, Y., McKinney, J. C., Feb. 2015. Global simulations of axisymmetric radiative black hole accretion discs in general relativity with a mean-field magnetic dynamo. MNRAS 447, 49–71.
  * Sa̧dowski and Narayan [2016] Sa̧dowski, A., Narayan, R., Mar. 2016. Three-dimensional simulations of supercritical black hole accretion discs - luminosities, photon trapping and variability. MNRAS 456 (4), 3929–3947.
  * Schwarm et al. [2017] Schwarm, F. W., Schönherr, G., Falkner, S., Pottschmidt, K., Wolff, M. T., Becker, P. A., Sokolova-Lapa, E., Klochkov, D., Ferrigno, C., Fürst, F., Hemphill, P. B., Marcu-Cheatham, D. M., Dauser, T., Wilms, J., Jan. 2017. Cyclotron resonant scattering feature simulations. I. Thermally averaged cyclotron scattering cross sections, mean free photon-path tables, and electron momentum sampling. A&A 597, A3.
  * Serim et al. [2017] Serim, M. M., Şahiner, Ş., ćerri-Serim, D., Inam, S. ć., Baykal, A., Nov. 2017. Discovery of a glitch in the accretion-powered pulsar SXP 1062. MNRAS 471 (4), 4982–4989.
  * Shakura and Sunyaev [1973] Shakura, N. I., Sunyaev, R. A., 1973. Black holes in binary systems. Observational appearance. A&A 24, 337–355.
  * Sheng et al. [2021] Sheng, Z., Wang, T., Ferland, G., Shu, X., Yang, C., Jiang, N., Chen, Y., Oct. 2021. Evidence of a Tidal-disruption Event in GSN 069 from the Abnormal Carbon and Nitrogen Abundance Ratio. ApJL 920 (1), L25.
  * Shih et al. [2010] Shih, I. C., Kundu, A., Maccarone, T. J., Zepf, S. E., Joseph, T. D., Sep. 2010. A Variable Black Hole X-ray Source in an NGC 1399 Globular Cluster. ApJ 721 (1), 323–328.
  * Shklovsky [1981] Shklovsky, I. S., Jun. 1981. The mass loss of SS 433 and its effect on the X-ray and radio emission of this source. Astr. Zh. 58, 554–560.
  * Sikora [1981] Sikora, M., Jul. 1981. Superluminous Accretion Discs. MNRAS 196, 257.
  * Skinner et al. [1982] Skinner, G. K., Bedford, D. K., Elsner, R. F., Leahy, D., Weisskopf, M. C., Grindlay, J., Jun. 1982. Discovery of 69 ms periodic X-ray pulsations in A0538 - 66. Nature 297 (5867), 568–570.
  * Song et al. [2020] Song, X., Walton, D. J., Lansbury, G. B., Evans, P. A., Fabian, A. C., Earnshaw, H., Roberts, T. P., Jan. 2020. The hunt for pulsating ultraluminous X-ray sources. MNRAS 491 (1), 1260–1277.
  * Soria [2013] Soria, R., Jan. 2013. Eccentricity of HLX-1. MNRAS 428, 1944–1949.
  * Soria et al. [2020] Soria, R., Blair, W. P., Long, K. S., Russell, T. D., Winkler, P. F., Jan. 2020. A New Microquasar Candidate in M83. ApJ 888 (2), 103.
  * Soria et al. [2005] Soria, R., Cropper, M., Pakull, M., Mushotzky, R., Wu, K., Jan. 2005. The star-forming environment of an ultraluminous X-ray source in NGC4559: an optical study. MNRAS 356, 12–28.
  * Soria et al. [2006] Soria, R., Fender, R. P., Hannikainen, D. C., Read, A. M., Stevens, I. R., Jun. 2006. An ultraluminous X-ray microquasar in NGC5408? MNRAS 368 (4), 1527–1539.
  * Soria and Kong [2016] Soria, R., Kong, A., Feb. 2016. Revisiting the ultraluminous supersoft source in M 101: an optically thick outflow model. MNRAS 456 (2), 1837–1858.
  * Soria et al. [2014] Soria, R., Long, K. S., Blair, W. P., Godfrey, L., Kuntz, K. D., Lenc, E., Stockdale, C., Winkler, P. F., Mar. 2014. Super-Eddington Mechanical Power of an Accreting Black Hole in M83. Science 343 (6177), 1330–1333.
  * Soria et al. [2010] Soria, R., Pakull, M. W., Broderick, J. W., Corbel, S., Motch, C., Dec. 2010. Radio lobes and X-ray hotspots in the microquasar S26. MNRAS 409 (2), 541–551.
  * Soria et al. [2021] Soria, R., Pakull, M. W., Motch, C., Miller-Jones, J. C. A., Schwope, A. D., Urquhart, R. T., Ryan, M. S., Feb. 2021. The ultraluminous X-ray source bubble in NGC 5585. MNRAS 501 (2), 1644–1662.
  * Staubert et al. [2019] Staubert, R., Trümper, J., Kendziorra, E., Klochkov, D., Postnov, K., Kretschmar, P., Pottschmidt, K., Haberl, F., Rothschild, R. E., Santangelo, A., Wilms, J., Kreykenbohm, I., Fürst, F., Feb. 2019. Cyclotron lines in highly magnetized neutron stars. A&A 622, A61.
  * Steele et al. [2014] Steele, M. M., Zepf, S. E., Maccarone, T. J., Kundu, A., Rhode, K. L., Salzer, J. J., Apr. 2014. Composition of an Emission Line System in Black Hole Host Globular Cluster RZ2109. ApJ 785 (2), 147.
  * Stephenson and Sanduleak [1977] Stephenson, C. B., Sanduleak, N., Apr. 1977. New H-alpha emission stars in the Milky Way. ApJs 33, 459–469.
  * Stobbart et al. [2004] Stobbart, A. M., Roberts, T. P., Warwick, R. S., Jul. 2004. A dipping black hole X-ray binary candidate in NGC 55. MNRAS 351 (3), 1063–1070.
  * Stobbart et al. [2006] Stobbart, A. M., Roberts, T. P., Wilms, J., May 2006. XMM-Newton observations of the brightest ultraluminous X-ray sources. MNRAS 368 (1), 397–413.
  * Straub et al. [2013] Straub, O., Done, C., Middleton, M., May 2013. The effect of advection at luminosities close to Eddington: The ULX in M 31. A&A 553, A61.
  * Strohmayer and Mushotzky [2003] Strohmayer, T. E., Mushotzky, R. F., Mar. 2003. Discovery of X-Ray Quasi-periodic Oscillations from an Ultraluminous X-Ray Source in M82: Evidence against Beaming. ApJL 586 (1), L61–L64.
  * Strohmayer and Mushotzky [2009] Strohmayer, T. E., Mushotzky, R. F., Oct. 2009. Evidence for an Intermediate-mass Black Hole in NGC 5408 X-1. ApJ 703 (2), 1386–1393.
  * Strohmayer et al. [2007] Strohmayer, T. E., Mushotzky, R. F., Winter, L., Soria, R., Uttley, P., Cropper, M., May 2007. Quasi-periodic Variability in NGC 5408 X-1. ApJ 660 (1), 580–586.
  * Sutton et al. [2014] Sutton, A. D., Done, C., Roberts, T. P., Nov. 2014. Irradiated, colour-temperature-corrected accretion discs in ultraluminous X-ray sources. MNRAS 444 (3), 2415–2427.
  * Sutton et al. [2013] Sutton, A. D., Roberts, T. P., Middleton, M. J., Oct. 2013. The ultraluminous state revisited: fractional variability and spectral shape as diagnostics of super-Eddington accretion. MNRAS 435 (2), 1758–1775.
  * Sutton et al. [2015] Sutton, A. D., Roberts, T. P., Middleton, M. J., Nov. 2015. X-Ray Spectral Residuals in NGC 5408 X-1: Diffuse Emission from Star Formation, or the Signature of a Super-Eddington Wind? ApJ 814 (1), 73.
  * Swartz et al. [2004] Swartz, D. A., Ghosh, K. K., Tennant, A. F., Wu, K., Oct. 2004. The Ultraluminous X-Ray Source Population from the Chandra Archive of Galaxies. ApJs 154 (2), 519–539.
  * Swartz et al. [2011] Swartz, D. A., Soria, R., Tennant, A. F., Yukita, M., Nov. 2011. A Complete Sample of Ultraluminous X-ray Source Host Galaxies. ApJ 741 (1), 49\.
  * Swartz et al. [2009] Swartz, D. A., Tennant, A. F., Soria, R., Sep. 2009. Ultraluminous X-Ray Source Correlations with Star-Forming Regions. ApJ 703 (1), 159–168.
  * Takahashi et al. [2018] Takahashi, H. R., Mineshige, S., Ohsuga, K., Jan. 2018. Supercritical Accretion onto a Non-magnetized Neutron Star: Why is it Feasible? apJ 853 (1), 45.
  * Takahashi and Ohsuga [2017] Takahashi, H. R., Ohsuga, K., Aug. 2017. General Relativistic Radiation MHD Simulations of Supercritical Accretion onto a Magnetized Neutron Star: Modeling of Ultraluminous X-Ray Pulsars. ApJL 845 (1), L9.
  * Takahashi et al. [2016] Takahashi, H. R., Ohsuga, K., Kawashima, T., Sekiguchi, Y., Jul. 2016. Formation of Overheated Regions and Truncated Disks around Black Holes: Three-dimensional General Relativistic Radiation-magnetohydrodynamics Simulations. ApJ 826 (1), 23.
  * Takeuchi et al. [2013] Takeuchi, S., Ohsuga, K., Mineshige, S., Aug. 2013. Clumpy Outflows from Supercritical Accretion Flow. PASJ 65, 88.
  * Taniguchi et al. [2000] Taniguchi, Y., Shioya, Y., Tsuru, T. G., Ikeuchi, S., Jun. 2000. Formation of Intermediate-Mass Black Holes in Circumnuclear Regions of Galaxies. PASJ 52, 533–537.
  * Tao et al. [2011] Tao, L., Feng, H., Grisé, F., Kaaret, P., Aug. 2011. Compact Optical Counterparts of Ultraluminous X-Ray Sources. ApJ 737 (2), 81.
  * Tao et al. [2019] Tao, L., Feng, H., Zhang, S., Bu, Q., Zhang, S., Qu, J., Zhang, Y., Mar. 2019. Super-Eddington Accretion onto the Galactic Ultraluminous X-Ray Pulsar Swift J0243.6+6124. ApJ 873 (1), 19.
  * Tetarenko et al. [2020] Tetarenko, B. E., Dubus, G., Marcel, G., Done, C., Clavel, M., Jul. 2020\. Thermally driven disc winds as a mechanism for X-ray irradiation heating in black hole X-ray binaries: the case study of GX339-4. MNRAS 495 (4), 3666–3682.
  * Tetarenko et al. [2018] Tetarenko, B. E., Lasota, J. P., Heinke, C. O., Dubus, G., Sivakoff, G. R., Feb. 2018. Strong disk winds traced throughout outbursts in black-hole X-ray binaries. NATURE 554 (7690), 69–72.
  * Tetarenko et al. [2016] Tetarenko, B. E., Sivakoff, G. R., Heinke, C. O., Gladstone, J. C., Feb. 2016. WATCHDOG: A Comprehensive All-sky Database of Galactic Black Hole X-ray Binaries. The Astrophysical Journal Supplement Series 222, 15.
  * Tong [2015] Tong, H., Nov. 2015. Ultraluminous X-ray pulsar: Accreting magnetar? Astronomische Nachrichten 336, 835.
  * Townsend and Charles [2020] Townsend, L. J., Charles, P. A., May 2020. Orbital and superorbital periods in ULX pulsars, disc-fed HMXBs, Be/X-ray binaries, and double-periodic variables. MNRAS 495 (1), 139–143.
  * Townsend et al. [2017] Townsend, L. J., Kennea, J. A., Coe, M. J., McBride, V. A., Buckley, D. A. H., Evans, P. A., Udalski, A., Nov. 2017. The 2016 super-Eddington outburst of SMC X-3: X-ray and optical properties and system parameters. MNRAS 471 (4), 3878–3887.
  * Trudolyubov [2008] Trudolyubov, S. P., Jun. 2008. XMM-Newton discovery of transient X-ray pulsar in NGC 1313. MNRAS 387 (1), L36–L40.
  * Trudolyubov et al. [2007] Trudolyubov, S. P., Priedhorsky, W. C., Córdova, F. A., Jul. 2007. Chandra and XMM-Newton Discovery of Transient X-Ray Pulsar in the Nearby Spiral Galaxy NGC 2403. ApJ 663 (1), 487–496.
  * Tsygankov et al. [2017] Tsygankov, S. S., Doroshenko, V., Lutovinov, A. A., Mushtukov, A. A., Poutanen, J., Sep. 2017. SMC X-3: the closest ultraluminous X-ray source powered by a neutron star with non-dipole magnetic field. A&A 605, A39.
  * Tsygankov et al. [2006] Tsygankov, S. S., Lutovinov, A. A., Churazov, E. M., Sunyaev, R. A., Sep. 2006. V0332+53 in the outburst of 2004-2005: luminosity dependence of the cyclotron line and pulse profile. MNRAS 371 (1), 19–28.
  * Tsygankov et al. [2016a] Tsygankov, S. S., Lutovinov, A. A., Doroshenko, V., Mushtukov, A. A., Suleimanov, V., Poutanen, J., Aug. 2016a. Propeller effect in two brightest transient X-ray pulsars: 4U 0115+63 and V 0332+53. A&A 593, A16.
  * Tsygankov et al. [2016b] Tsygankov, S. S., Mushtukov, A. A., Suleimanov, V. F., Poutanen, J., Mar. 2016b. Propeller effect in action in the ultraluminous accreting magnetar M82 X-2. MNRAS 457 (1), 1101–1106.
  * Tzanavaris et al. [2016] Tzanavaris, P., Hornschemeier, A. E., Gallagher, S. C., Lenkić, L., Desjardins, T. D., Walker, L. M., Johnson, K. E., Mulchaey, J. S., Feb. 2016. Exploring X-Ray Binary Populations in Compact Group Galaxies with Chandra. ApJ 817 (2), 95.
  * Urpin and Geppert [1995] Urpin, V., Geppert, U., Aug. 1995. Accretion and evolution of the neutron star magnetic field. MNRAS 275 (4), 1117–1124.
  * Urquhart and Soria [2016a] Urquhart, R., Soria, R., Feb. 2016a. Optically thick outflows in ultraluminous supersoft sources. MNRAS 456 (2), 1859–1880.
  * Urquhart and Soria [2016b] Urquhart, R., Soria, R., Nov. 2016b. Two Eclipsing Ultraluminous X-Ray Sources in M51. ApJ 831 (1), 56.
  * Uttley et al. [2014] Uttley, P., Cackett, E. M., Fabian, A. C., Kara, E., Wilkins, D. R., Aug. 2014. X-ray reverberation around accreting black holes. A&Ar 22, 72.
  * Van Booy [2009] Van Booy, S., May 2009. Love Begins in Winter: Five Stories.
  * van den Eijnden et al. [2018] van den Eijnden, J., Degenaar, N., Russell, T. D., Wijnands, R., Miller-Jones, J. C. A., Sivakoff, G. R., Hernández Santisteban, J. V., Sep. 2018. An evolving jet from a strongly magnetized accreting X-ray pulsar. Nature 562 (7726), 233–235.
  * van den Eijnden et al. [2019] van den Eijnden, J., Degenaar, N., Schulz, N. S., Nowak, M. A., Wijnands, R., Russell, T. D., Hernández Santisteban, J. V., Bahramian, A., Maccarone, T. J., Kennea, J. A., Heinke, C. O., Aug. 2019\. Chandra reveals a possible ultrafast outflow in the super-Eddington Be/X-ray binary Swift J0243.6+6124. MNRAS 487 (3), 4355–4371.
  * van Paradijs [1996] van Paradijs, J., Jun. 1996. On the Accretion Instability in Soft X-Ray Transients. ApJL 464, L139.
  * Vasilopoulos et al. [2018] Vasilopoulos, G., Haberl, F., Carpano, S., Maitra, C., Dec. 2018. NGC 300 ULX1: A test case for accretion torque theory. A&A 620, L12.
  * Vasilopoulos et al. [2021] Vasilopoulos, G., Koliopanos, F., Haberl, F., Treiber, H., Brightman, M., Earnshaw, H. P., Gúrpide, A., Feb. 2021. Chandra probes the X-ray variability of M51 ULX-7: evidence of propeller transition and X-ray dips on orbital periods. arXiv e-prints, arXiv:2102.07996.
  * Vasilopoulos et al. [2020a] Vasilopoulos, G., Lander, S. K., Koliopanos, F., Bailyn, C. D., Feb. 2020a. M51 ULX-7: superorbital periodicity and constraints on the neutron star magnetic field. MNRAS 491 (4), 4949–4959.
  * Vasilopoulos et al. [2019] Vasilopoulos, G., Petropoulou, M., Koliopanos, F., Ray, P. S., Bailyn, C. B., Haberl, F., Gendreau, K., Oct. 2019. NGC 300 ULX1: spin evolution, super-Eddington accretion, and outflows. MNRAS 488 (4), 5225–5231.
  * Vasilopoulos et al. [2020b] Vasilopoulos, G., Ray, P. S., Gendreau, K. C., Jenke, P. A., Jaisawal, G. K., Wilson-Hodge, C. A., Strohmayer, T. E., Altamirano, D., Iwakiri, W. B., Wolff, M. T., Guillot, S., Malacaria, C., Stevens, A. L., Jun. 2020b. The 2019 super-Eddington outburst of RX J0209.6-7427: detection of pulsations and constraints on the magnetic field strength. MNRAS 494 (4), 5350–5359.
  * Vaughan and Nowak [1997] Vaughan, B. A., Nowak, M. A., Jan. 1997. X-Ray Variability Coherence: How to Compute It, What It Means, and How It Constrains Models of GX 339-4 and Cygnus X-1. ApJL 474 (1), L43–L46.
  * Vinokurov et al. [2013] Vinokurov, A., Fabrika, S., Atapin, K., Apr. 2013. Ultra-luminous X-ray sources as supercritical accretion disks: Spectral energy distributions. Astrophysical Bulletin 68 (2), 139–153.
  * Voges et al. [1999] Voges, W., Aschenbach, B., Boller, T., Bräuninger, H., Briel, U., Burkert, W., Dennerl, K., Englhauser, J., Gruber, R., Haberl, F., Hartner, G., Hasinger, G., Kürster, M., Pfeffermann, E., Pietsch, W., Predehl, P., Rosso, C., Schmitt, J. H. M. M., Trümper, J., Zimmermann, H. U., Sep. 1999. The ROSAT all-sky survey bright source catalogue. A&A 349, 389–405.
  * von Zeipel [1910] von Zeipel, H., Mar. 1910. Sur l’application des séries de M. Lindstedt à l’étude du mouvement des comètes périodiques. Astronomische Nachrichten 183 (22), 345.
  * Waisberg et al. [2019] Waisberg, I., Dexter, J., Olivier-Petrucci, P., Dubus, G., Perraut, K., Apr. 2019. Collimated radiation in SS 433. Constraints from spatially resolved optical jets and Cloudy modeling of the optical bullets. A&A 624, A127.
  * Walton et al. [2018a] Walton, D. J., Bachetti, M., Fürst, F., Barret, D., Brightman, M., Fabian, A. C., Grefenstette, B. W., Harrison, F. A., Heida, M., Kennea, J., Kosec, P., Lau, R. M., Madsen, K. K., Middleton, M. J., Pinto, C., Steiner, J. F., Webb, N., Apr. 2018a. A Potential Cyclotron Resonant Scattering Feature in the Ultraluminous X-Ray Source Pulsar NGC 300 ULX1 Seen by NuSTAR and XMM-Newton. ApJL 857 (1), L3.
  * Walton et al. [2016a] Walton, D. J., Fürst, F., Bachetti, M., Barret, D., Brightman, M., Fabian, A. C., Gehrels, N., Harrison, F. A., Heida, M., Middleton, M. J., Rana, V., Roberts, T. P., Stern, D., Tao, L., Webb, N., Aug 2016a. A 78 Day X-Ray Period Detected from NGC 5907 ULX1 by Swift. ApJL 827 (1), L13.
  * Walton et al. [2017] Walton, D. J., Fürst, F., Harrison, F. A., Middleton, M. J., Fabian, A. C., Bachetti, M., Barret, D., Miller, J. M., Ptak, A., Rana, V., Stern, D., Tao, L., Apr. 2017. The Broadband Spectral Variability of Holmberg IX X-1. ApJ 839 (2), 105.
  * Walton et al. [2018b] Walton, D. J., Fürst, F., Harrison, F. A., Stern, D., Bachetti, M., Barret, D., Brightman, M., Fabian, A. C., Middleton, M. J., Ptak, A., Tao, L., Feb. 2018b. Super-Eddington accretion on to the neutron star NGC 7793 P13: Broad-band X-ray spectroscopy and ultraluminous X-ray sources. MNRAS 473 (4), 4360–4376.
  * Walton et al. [2018c] Walton, D. J., Fürst, F., Heida, M., Harrison, F. A., Barret, D., Stern, D., Bachetti, M., Brightman, M., Fabian, A. C., Middleton, M. J., Apr. 2018c. Evidence for Pulsar-like Emission Components in the Broadband ULX Sample. ApJ 856, 128.
  * Walton et al. [2022] Walton, D. J., Mackenzie, A. D. A., Gully, H., Patel, N. R., Roberts, T. P., Earnshaw, H. P., Mateos, S., Jan. 2022. A multimission catalogue of ultraluminous X-ray source candidates. MNRAS 509 (2), 1587–1604.
  * Walton et al. [2016b] Walton, D. J., Middleton, M. J., Pinto, C., Fabian, A. C., Bachetti, M., Barret, D., Brightman, M., Fuerst, F., Harrison, F. A., Miller, J. M., Stern, D., Aug. 2016b. An Iron K Component to the Ultrafast Outflow in NGC 1313 X-1. ApJL 826 (2), L26.
  * Walton et al. [2015] Walton, D. J., Middleton, M. J., Rana, V., Miller, J. M., Harrison, F. A., Fabian, A. C., Bachetti, M., Barret, D., Boggs, S. E., Christensen, F. E., Craig, W. W., Fuerst, F., Grefenstette, B. W., Hailey, C. J., Madsen, K. K., Stern, D., Zhang, W., Jun. 2015. NuSTAR, XMM-Newton, and Suzaku Observations of the Ultraluminous X-Ray Source Holmberg II X-1. ApJ 806 (1), 65.