# Search for (sub)stellar companions of exoplanet hosts by exploring the
second ESA-Gaia data release

K.-U. Michel 1,∗ & M. Mugrauer 1

###### Abstract

We present the latest results of an ongoing multiplicity survey of exoplanet
hosts, which was initiated at the Astrophysical Institute and University
Observatory Jena, using data from the second data release of the ESA-Gaia
mission. In this study the multiplicity of 289 targets was investigated, all
located within a distance of about 500 pc from the Sun. In total, 41 binary,
and 5 hierarchical triple star systems with exoplanets were detected in the
course of this project, yielding a multiplicity rate of the exoplanet hosts of
about 16 %. A total of 61 companions (47 stars, a white dwarf, and 13 brown
dwarfs) were detected around the targets, whose equidistance and common proper
motion with the exoplanet hosts were proven with their precise Gaia DR2
astrometry, which also agrees with the gravitational stability of most of
these systems. The detected companions exhibit masses from about 0.016 up to
1.66 M⊙ and projected separations in the range between about 52 and 9555 au.

##  1 Keywords:

Multiple Stars, White Dwarfs, Brown Dwarfs, Exoplanets, ESA-Gaia DR2

##  2 Introduction

Since the detection of the first planet orbiting a star other than the Sun,
several thousands of these exoplanets have been discovered by various
detection techniques. While the majority of stars are members of multiple star
systems (Duchêne and Kraus, 2013), most of the exoplanet host stars are single
stars. Nevertheless several multiple star systems hosting exoplanets, could
already be revealed by previous multiplicity studies using seeing limited or
high contrast AO imaging observations (see e.g. Mugrauer et al., 2014;
Mugrauer and Ginski, 2015). In order to explore the effects of the presence of
stellar companions on the formation process and orbital evolution of
exoplanets, a survey was initiated at the Astrophysical Institute and
University Observatory Jena (described in detail by Mugrauer, 2019) to
identify and characterize companions of exoplanet host stars, detected in the
second data release of the European Space Agency (ESA) Gaia mission (Gaia DR2
from hereon, Gaia Collaboration et al., 2018). Furthermore, in Mugrauer and
Michel (2020) a comparable investigation was carried out among potential
exoplanet host stars, identified by the TESS mission (Ricker et al., 2015).
The study, whose results are presented here, is the third work in the context
with Mugrauer (2019). The following section gives a detailed description of
this study, and the detected companions and their derived properties are
presented in the third section of this paper.

##  3 Gaia DR2 search for (sub)stellar companions of exoplanet hosts

The Gaia DR2, is based on data taken by the Gaia spacecraft in the first 22
months of its mission and contains $1.7$ billion detected sources up to a
limiting magnitude of $G=21$ mag. For 1.3 billion sources a five parameter
astrometric solution could be derived, i.e. beside their equatorial
coordinates ($\alpha$, $\delta$), also the parallax $\pi$ and proper motion
($\mu_{\alpha}cos(\delta)$, $\mu_{\delta}$) of these sources were determined.
Furthermore, for about 88 million detected objects estimates of their G-band
extinction and effective temperature are listed in the Gaia DR2, determined by
the Priam algorithm, which is part of the astrophysical parameters inference
system (Apsis, see Bailer-Jones et al., 2013) in the Gaia data processing.

Using Gaia DR2 data Mugrauer (2019) already explored the multiplicity of all
exoplanet host stars, whose exoplanets were detected either by photometric
transit observations, radial-velocity (RV), or astrometric measurements, and
were listed in the Extrasolar Planets Encyclopaedia111Online available at:
http://exoplanet.eu/ (EPE from hereon, Schneider et al., 2011) by mid of
October 2018. The study, presented in this paper, complements this survey by
investigating the multiplicity of the exoplanet hosts (stars but also brown
dwarfs), whose planets were indirectly detected either via RV measurements or
transit observations in the range of time between mid of October 2018 until
end of September 2020, as well as all exoplanet hosts, known so far, with
planets, which were directly detected by imaging observations. At the end of
September 2020 the EPE lists about 4350 exoplanets, and about 400 of them were
detected around the hosts studied in this work.

(Sub)stellar Companions are expected to be located at the same distance to the
Sun as the exoplanet hosts and form common proper motion pairs with them, in
particular wide companions with projected separations of hundreds and
thousands of au, i.e. the typical targets of this study. Hence, in order to
clearly detect such companions and to prove the equidistance of these objects
and the exoplanet hosts, in this study we have taken into account only Gaia
DR2 sources with an accurate five parameter astrometric solution, i.e. which
exhibit precise measurements of their parallax ($\pi/\sigma(\pi)>3$) and
proper motion ($\mu/\sigma(\mu)>3$). Thereby, sources with negative parallaxes
are neglected. As in the Gaia DR2 a parallax uncertainty of 0.7 mas is reached
for faint sources down to $G=20$ mag, the survey is furthermore constrained to
exoplanet hosts, which are located within a distance of 500 pc around the Sun
(i.e. $\pi>2$ mas), to assure $\pi/\sigma(\pi)>3$ even for the faintest
companions, detectable in this survey. This distance constraint is slightly
relaxed to $\pi+3\sigma(\pi)\gtrapprox 2$ mas, i.e. taking into account also
the parallax uncertainty of the hosts. By the end of September 2020, in total
289 exoplanet hosts are listed in the EPE, which fulfill this distance
constraint, and hence are selected as targets for this study. The properties
of all targets are summarized in Tab. 1 and their histograms are illustrated
in Fig. 1. On average, the targets are solar like stars most frequently found
within 150 pc around the Sun, which exhibit proper motions in the range
between about 2 and 10400 mas/yr, and G-band magnitudes from about 3.7 to 20.8
mag. In particular, the sub-sample of direct imaging exoplanet hosts emerges
as a peak in the age distribution at young ages, as all these targets are
typically younger than 0.1 Gyr, in contrast to hosts of RV and transiting
exoplanets, which are older than 1 Gyr in general.

The companion search radius, applied in this project around the selected
targets, is limited to a maximal projected separation of 10000 au, which
guarantees that the majority of wide companions of the exoplanet hosts are
detectable in this study, as described by Mugrauer (2019). This upper
separation limit results in an angular search radius around the targets of
$r[\text{arcsec}]=10\pi[\text{mas}]$. Within this radius around the targets
the companionship of all sources, listed in the Gaia DR2 with an accurate five
parameter astrometric solution was investigated. For the verification of the
equidistance of all detected sources with the associated exoplanet hosts, the
difference $\Delta\pi$ between their parallaxes was calculated, taking into
account also the excess noise of their astrometric solutions. Common proper
motion of the detected sources and the targets was checked with the precise
Gaia DR2 proper motions of the exoplanet hosts $\mu_{PH}$ and the sources
$\mu_{Comp}$. In addition, we have also derived for all sources the
differential proper motion: $\mu_{rel}=|\mu_{PH}-\mu_{Comp}|$, which yields
the common proper motion index ($\textrm{cpm-
index}=|\mu_{PH}+\mu_{Comp}|/\mu_{rel}$), which characterizes the degree of
common proper motion of the detected sources and the exoplanet hosts.

Following the companion identification procedure ($sig$-$\Delta\pi\leq 3$ &
$\textrm{cpm-index}\geq 3$), as defined by Mugrauer (2019) the majority of all
sources ($>$99.88 %), detected within the applied search radius around the
targets, can clearly be excluded as companions, as they are either not located
at the same distances as the exoplanet hosts and/or do not share a common
proper motion with them. In contrast, for 61 detected objects their
companionship with the targets could clearly be proven with their precise Gaia
DR2 astrometry. For all these companions we have determined their relative
astrometry to the exoplanet hosts (angular separation $\rho$, and position
angle $PA$), as well as their projected separation $sep$, derived with their
angular separation and the parallax of the targets.

The absolute G-band magnitude of all companions was derived from their
apparent G-band photometry, the parallax of the associated exoplanet hosts, as
well as their Apsis-Priam G-band extinction estimate, all listed in the Gaia
DR2. If there was no extinction estimate given for a companion, the extinction
estimate of the exoplanet host was used instead or if not available, its
extinction estimate, listed in the StarHorse catalog (Anders et al., 2019). In
the case that no G-band extinction is available at all it was derived from
V-band extinction measurements of the exoplanet hosts, listed either in the
VizieR data base222Online available at: https://vizier.u-strasbg.fr/
(Ochsenbein et al., 2000) or in the literature, adopting $A_{G}/A_{V}=0.77$,
as described by Mugrauer (2019).

The masses and effective temperatures of all detected companions were
determined from their derived absolute G-band magnitudes using the
evolutionary models of (sub)stellar objects from Baraffe et al. (2015), as
well as the ages of the exoplanet hosts, as listed in the EPE. Thereby, we
adopt the same age for the planet hosts and their companions. We determined
the masses and effective temperatures of the companions via interpolation of
the model grid with the age closest to that of the exoplanet hosts. For
verification of the obtained results the properties of the companions derived
from their G-band magnitudes were compared with those, determined from the
near-infrared photometry, taken from the 2MASS Point Source catalogue
(Skrutskie et al., 2006), if available. For the near-infrared extinction we
have used the relations: $A_{Ks}/A_{V}=0.12$, $A_{H}/A_{V}=0.17$, and
$A_{J}/A_{V}=0.26$, as described in Mugrauer (2019). A graphical comparison of
the masses obtained from the G-band and the 2MASS photometry are shown in Fig.
2. The identity is illustrated as grey dashed line in this figure. For all
companions the derived masses agree well with each other, with deviations that
remain below the $3\sigma$ level (the same holds also for the temperature
estimates not shown here). Objects, whose masses were determined by
extrapolation from the used model grids as such as those with bad quality
(quality flags all but A) or contaminated 2MASS photometry were excluded in
this comparison.

Eventually for all companions, which were detected in this study, we have
estimated their escape velocity
$\mu_{esc}\,[mas\,yr^{-1}]=2\pi\sqrt{2M\pi^{3}_{PH}/\rho}$ with their angular
separation $\rho$ and the parallax of the associated exoplanet hosts both in
the unit of milli-arcsec (mas), as well as the total mass $M$ of the system
(in the unit $M_{\odot}$), i.e. the sum of the mass of the companions, derived
as describe above, and the mass of the associated exoplanet hosts, taken from
the EPE. This estimation can be considered as an upper limit of the escape
velocity as the projected separation is smaller than the physical separation
of the objects.

##  4 Detected companions of exoplanet hosts

The Gaia astro- and photometry of all exoplanet hosts and their companions,
detected in this study, are listed in Tab. 2. The derived properties of the
companions are summarized in Tab. 3 to 5. In all tables the exoplanet host
systems or the companions are sorted by their right ascension. The used
identifier of the targets corresponds either to the one used in the EPE or is
a slightly abbreviated version of it. In contrast to the planet definition
used by the EPE, in which substellar objects below 60 $M_{Jup}$ are defined as
exoplanets, we follow here the planet definition based on the deuterium
burning limit (as described e.g. by Basri, 2000), i.e. all substellar objects
below 13 $M_{Jup}$ are classified as exoplanets, while more massive objects
below the substellar/stellar mass limit (at about 0.072 $M_{Jup}$ for solar
metallicity) as brown dwarfs, respectively. Thereby the given masses of the
exoplanets, detected by radial velocity measurements, correspond to minimum-
masses ($M\sin(i)$) due to the unknown orbital inclination, while masses of
direct imaging planets are usually derived from their spectrophotometry with
evolutionary models.

In Tab. 2 for each exoplanet host and its detected co-moving companion(s)
their Gaia DR2 parallax $\pi$, proper motion in right ascension and
declination ($\mu_{\alpha}\cos(\delta)$ & $\mu_{\delta}$), astrometric excess
noise (epsi) with its significance (sig-epsi), apparent G-band magnitude, as
well as the used Apsis-Priam G-band extinction estimate $A_{G}$ are listed. In
the case that the G-band extinction was taken from the StarHorse catalog this
is indicated with the SHC flag, or with the $\maltese$ flag if the G-band
extinction was derived from V-band extinction measurements, either listed in
the VizieR database or from the literature. In this table the exoplanet hosts
are indicated with *, and known spectroscopic binary stars among them with
(SB).

Table 3 lists for each detected companion its angular separation ($\rho$) and
position angle ($PA$) to the associated exoplanet host, which were determined
with the Gaia DR2 astrometry of the objects for the (Gaia reference) epoch
2015.5. The relative astrometry of the companions exhibits an uncertainty on
average of 0.3 mas in angular separation, and 0.002 ∘ in position angle,
respectively. In the following columns of Tab. 3 we list the parallax
difference ($\Delta\pi$) with its significance (in brackets calculated by
taking into account also the Gaia astrometric excess noise333The astrometric
excess noise is conservatively considered here as additional parallax
uncertainty of the source.) between the exoplanet hosts and their detected
companions, their differential proper potion $\mu_{rel}$ with its
significance, and the cpm-index of all systems. The precise Gaia DR2
astrometry proves the equidistance (sig-$\Delta\pi<2.3\,\sigma$, average value
of $0.5\,\sigma$) and common proper motion ($\textrm{cpm-index}>6$,
$\textrm{average cpm-index}=118$) of the exoplanet hosts and their companions.
If these companions are not listed yet as companion(-candidates) in the
Washington Double Star Catalog (WDS from hereon, Mason et al., 2001) this is
indicated with the $\bigstar$ flag in last column of Tab. 3. In the case that
the companion is not listed in the WDS but was reported in literature before,
additional information is given in the notes of this table.

In Tab. 4 beside the equatorial coordinates ($\alpha$, $\delta$ both for epoch
2015.5) of all detected companions, their derived absolute G-band magnitude
$M_{G}$, projected separation $sep$ to the associated exoplanet host (relative
uncertainty about 1 %, on average), mass, and effective temperature $T_{eff}$
are summarized. The flags listed in the last column of this table are defined
as follows:

  * •

PRI: An Apsis-Priam temperature estimate is available for the detected
companion, which could be compared with the effective temperature of the
companion, derived from its absolute G-band photometry using the Baraffe et
al. (2015) models.

  * •

2MA: The companion is listed in the 2MASS Point Source catalogue.

  * •

BPRP: The $G_{BP}-G_{RP}$ color of the exoplanet host and of the detected
companion is listed in the Gaia DR2, hence a color comparison was feasible.

  * •

EXT: Because of its brightness the companion exceeds the magnitude range of
the Baraffe et al. (2015) evolutionary models. Therefore, the properties of
the companion were estimated via extrapolation from the two brightest sources
of the used model isochrone.

  * •

WD: The detected companion is a white dwarf.

  * •

BD: The detected companion is a brown dwarf.

Finally, in Tab. 5 we summarize all those detected companions, whose
differential proper motion $\mu_{rel}$ significantly exceeds their expected
escape velocity $\mu_{rel}$. Companions, which are already known to be members
of hierarchical triple star systems, are indicated with the flag *** in the
last column of this table.

Among all 289 targets, whose multiplicity was investigated in the study, whose
results are presented in this paper, 41 binary and 5 hierarchical triple star
systems with exoplanets were identified. This yields a multiplicity rate of
the targets of $16\pm$2%, very well consistent with the multiplicity rate of
exoplanet host stars of $15\pm 1$ %, reported before by Mugrauer (2019). This
is as expected, as the sensitivities of the two surveys should agree well with
each other, as the brightness and mass of their targets match, and the
distance of the targets from this survey is on average about 40 % smaller than
that of the targets from Mugrauer (2019), resulting in a reduction in the
distance modulus of only about 1 mag. In total, 61 companions (48 stars and 13
brown dwarfs) could be detected in the Gaia DR2 around the targets. The
detected substellar companions are all listed as exoplanets in the EPE. The
cumulative distribution functions of the derived properties (projected
separation, mass and effective temperature) of theses companions, are
illustrated in Fig. 3, 4, and 5. The separation-mass diagram of the companions
is shown in Fig. 6. As described above, the accurate Gaia DR2 astrometry
proves the equidistance and common proper motion of all detected companions
with the associated exoplanet hosts, and for the majority of these companions
their differential proper motion to the exoplanet hosts is slower than their
estimated escape velocity, facts that are expected for gravitationally bound
systems. In contrast, the differential proper motion of the companions, which
are listed in Tab. 5, exceeds their estimated escape velocity, possibly
indicating a higher degree of multiplicity.444Additional close companions
either of the exoplanet hosts or of the companions force these objects on
close orbits with high orbital velocities around a common barycenter that
could induce the observed high differential velocities. Indeed, one of these
companions (51 Eri BC) is already known to be a close binary itself. The
remaining 2 companions and their primaries are promising targets for follow-up
observations to check their multiplicity status e.g. with high contrast AO
imaging observations.

All detected companions exhibit projected separations to the associated
exoplanet hosts in the range between 52 and 9555 au (average separation of
about 2310 au). The highest companion frequency is found at projected
separations between about 240 and 400 au and half of all companions are
located at projected separations below about 1240 au. The closest detected
companion is K2-288 A, which is separated from the exoplanet host stars K2-288
B by 52 au, and it is the only companion identified in this study within a
projected separation of 100 au. The masses of the companions range between
0.016 and 1.66 $M_{\odot}$ (average mass of 0.36 $M_{\odot}$) and companions
are found most frequently in the substellar mass regime between 0.016 up to
0.033 $M_{\odot}$, while more massive companions are detected at a lower but
constant frequency up to about 0.7 $M_{\odot}$, and only about 10 % of all the
detected companions exhibit masses larger than 0.7 $M_{\odot}$. The companions
exhibit effective temperatures in the range between about 1850 and 6350 K
(average temperature of about 3400 K), which corresponds to spectral types of
L3 to F6 (M3, on average), according to the $T_{eff}-SpT$ relation555Online
available at:
http://www.pas.rochester.edu/~emamajek/EEM_dwarf_UBVIJHK_colors_Teff.txt from
(Pecaut and Mamajek, 2013).

In general the effective temperature of the detected companions, determined
with their derived absolute G-band magnitude, using the evolutionary Baraffe
et al. (2015) models, agree well with their Gaia DR2 Apsis-Priam temperature
estimate (if available) with a characteristic deviation of about $\pm$350 K,
consistent with the typical uncertainty of the different temperature
estimates, which is in the order of about 330 K. Only in the case of HIP 38594
B the temperature estimate, based on the absolute G-band photometry of the
companion significantly deviates by more than 2300 K from its Apsis-Priam
temperature estimate, which is also about 900 K higher than the one of the
associated exoplanet host star HIP 38594 A. Furthermore, the companion appears
bluer ($\Delta(G_{BP}-G_{RP})=-0.669\pm 0.004$ mag) than its primary although
it is about 7 mag fainter in the G-band than the exoplanet host star. The
intrinsic faintness and high temperature of HIP 38594 B clearly indicates that
this companion is a white dwarf. This conclusion is consistent with the
results of Subasavage et al. (2008), who have already classified the companion
spectroscopically as a white dwarf, and have denote it as WD 0751-252. For
this degenerated companion we adopt here a mass of about 0.6 $M_{\odot}$.

In Fig. 7 the G-band magnitude difference of all detected companions to the
associated exoplanet hosts is plotted versus their angular separation. For
comparison we show as dashed line in this figure the estimate of the Gaia
detection limit, reported by Mugrauer (2019) which was further constrained by
Mugrauer and Michel (2020). Companions of exoplanet hosts brighter than 12.8
mag are plotted as open circles those of hosts, which are fainter than that
magnitude limit, as filled black circles, respectively. A magnitude difference
of about 5 mag is reached at an angular separation of about 2 arcsec,
consistent with the estimate of the Gaia detection limit, determined by
Mugrauer (2019). Only two companions significantly exceed the limit estimate,
namely K2-288 A at an angular separation of about 0.8 arcsec with $\Delta
G\sim 1.2$ mag and HIP 77900 B, at 22.3 arcsec with $\Delta G\sim 13.5$ mag.
While K2-288 A is a companion of a target fainter than $G=12.8$ mag for which
Gaia reaches a higher sensitivity at angular separations slightly below 1
arcsec (up to 3 mag, as described by Mugrauer and Michel, 2020) the detection
of HIP 77900 B indicates that the given limit estimate might be too
conservative at angular separations beyond about 20 arcsec.

##  5 Summary and Outlook

The study, presented here, is a continuation of a survey, which was initiated
at the Astrophysical Institute and University Observatory Jena, to investigate
the multiplicity status of exoplanet hosts and to characterize the properties
of their detected (sub)stellar companions, using accurate Gaia astro- and
photometry. In this paper the multiplicity of 289 exoplanet hosts was explored
and (sub)stellar companions were detected around 60 targets. The companionship
of these objects with the exoplanet hosts could be proven with their accurate
Gaia DR2 astrometry (equidistance, common proper motion, and differential
proper motion smaller than the expected escape velocity). The mass and
effective temperature of all companions were determined with their derived
absolute G-band photometry and the Baraffe et al. (2015) evolutionary models
of (sub)stellar objects. In total, 61 companions (beside 48 stellar
companions, among them the white dwarf HIP 38594 B, also 13 brown dwarfs) were
detected in this project, and 14 of these objects are neither listed in the
WDS as companion(-candidate)s of the targets nor were described in the
literature before. A total of 41 binary and 5 triple star systems with
exoplanets, were identified in this study, yielding a multiplicity rate of the
targets of about 16 %, which is very well consistent with the multiplicity
rate of exoplanet host stars, reported by Mugrauer (2019). Following the
standard procedure of our survey, all detected companions and their derived
properties will be made available online in the VizieR database. The survey,
whose latest results are presented here, is an ongoing project as more and
more exoplanet hosts are detected by different planet detection methods, whose
multiplicity status needs to be investigated. Furthermore, there are sources,
listed in the Gaia DR2, within the applied search radius around the targets,
which still lack a five parameter astrometric solution. Hence, further
companions of the exoplanet hosts, investigated here, should exist, whose
companionship can be proven with accurate astrometric measurements, provided
by future data releases of the ESA-Gaia mission, e.g. the Gaia EDR3, planed to
be published end of 2020.

The results of this survey, which is mainly sensitive for wide companions of
exoplanet hosts, combined with those of our currently ongoing large high
contrast imaging surveys (sensitive for close companions), carried out with
SPHERE/VLT and AstraLux/CAHA (first results are already published e.g. by
Ginski et al., 2020) will yield a complete characterization of the
multiplicity status of the observed targets. This will eventually allow to
draw conclutions on the impact of the stellar multiplicity on the formation
process of planets and the evolution of their orbits.

## Acknowledgments

We thank the two anonymous referees for their helpful and constructive
comments on the manuscript.

We made use of data from:

(1) the Simbad and VizieR databases, both operated at CDS in Strasbourg,
France.

(2) the European Space Agency (ESA) mission Gaia
(https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and
Analysis Consortium (DPAC,
https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has
been provided by national institutions, in particular the institutions
participating in the Gaia Multilateral Agreement.

(3) the Two Micron All Sky Survey, which is a joint project of the University
of Massachusetts and the Infrared Processing and Analysis Center/California
Institute of Technology, funded by the National Aeronautics and Space
Administration and the National Science Foundation.

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##  6 Tables

Table 1: The properties of all targets of this study. The corresponding histograms are shown in Fig. 1. | Distance | $\mu$ | G | age | mass
---|---|---|---|---|---
|  $[$pc$]$ |  $[$mas/yr$]$ |  $[$mag$]$ |  $[$Gyr$]$ | $[M_{\odot}]$
min | 1.8 | 1.7 | 3.7 | 0.001 | 0.016
max | 586 | 10394 | 20.8 | 14.9 | 20
ave | 137 | 270 | 10.8 | 3.5 | 1.1
med | 94 | 65 | 10.7 | 2.1 | 1.0
Table 2: Gaia astro- and photometry of all exoplanet hosts and their companions, detected in this study. Name | $\pi$ | $\mu_{\alpha}cos(\delta)$ | $\mu_{\delta}$ | $epsi$ |  $sig$- | G | $A_{G}$ |
---|---|---|---|---|---|---|---|---
| [mas] | [mas/yr] | [mas/yr] | [mas] | $epsi$ | [mag] | [mag] |
HD 1160 A* |  $7.9417\pm 0.0764$ | $\,\,\,\,20.089\pm 0.138$ | $-14.575\pm 0.099$ | $0.121$ | $6.0$ | $\,\,\,7.1074\pm 0.0003$ | $0.1347_{-0.0968}^{+0.1300}$ |
HD 1160 C |  $6.9946\pm 0.2739$ | $\,\,\,\,20.605\pm 0.333$ | $-16.215\pm 0.311$ | $0.739$ | $37$ | $15.3505\pm 0.0207$ |  |
Gliese 49 A* | $101.4650\pm 0.0335\,\,\,$ | $\,\,731.135\pm 0.041$ | $\,\,\,\,90.690\pm 0.048$ | $-$ | $-$ | $\,\,\,8.6628\pm 0.0007$ | $0.6030_{-0.4095}^{+0.2220}$ |
Gliese 49 B | $101.6371\pm 0.0806\,\,\,$ | $\,\,730.740\pm 0.163$ | $\,\,\,\,86.352\pm 0.225$ | $0.190$ | $13$ | $11.9238\pm 0.0033$ |  |
HD 8326 A* | $32.5591\pm 0.0466$ | $-58.470\pm 0.120$ | $-224.887\pm 0.064\,\,\,\,$ | $-$ | $-$ | $\,\,\,8.4749\pm 0.0004$ |  |
HD 8326 B | $32.4362\pm 0.0589$ | $-57.577\pm 0.156$ | $-224.122\pm 0.088\,\,\,\,$ | $0.347$ | $27$ | $14.2066\pm 0.0006$ | $0.2940_{-0.0438}^{+0.2446}$ |
HD 13167 A* |  $6.6859\pm 0.0485$ | $\,\,\,\,43.770\pm 0.077$ | $-38.126\pm 0.079$ | $-$ | $-$ | $\,\,\,8.1600\pm 0.0003$ |  |
HD 13167 B |  $6.7931\pm 0.1254$ | $\,\,\,\,44.134\pm 0.215$ | $-39.358\pm 0.212$ | $0.444$ | $3.3$ | $17.4513\pm 0.0022$ | $0.2431_{-0.0648}^{+0.0597}$ | SHC
HR 858 A* | $31.2565\pm 0.0700$ | $123.229\pm 0.070$ | $\,\,105.788\pm 0.151$ | $0.086$ | $3.9$ | $\,\,\,6.2480\pm 0.0003$ | $0.1320_{-0.0911}^{+0.1061}$ |
HR 858 B | $32.3014\pm 0.1670$ | $137.125\pm 0.213$ | $\,\,105.865\pm 0.302$ | $0.835$ | $63$ | $16.0464\pm 0.0031$ |  |
HD 18015 A* |  $8.0490\pm 0.0517$ | $\,\,\,\,63.053\pm 0.089$ | $\,\,\,-4.359\pm 0.082$ | $-$ | $-$ | $\,\,\,7.7219\pm 0.0005$ |  |
HD 18015 B |  $7.9413\pm 0.0415$ | $\,\,\,\,64.638\pm 0.071$ | $\,\,\,-4.668\pm 0.066$ | $-$ | $-$ | $12.2361\pm 0.0008$ | $0.1440_{-0.0325}^{+0.0361}$ |
K2-288 B* | $15.2166\pm 0.2007$ | $185.476\pm 0.708$ | $-74.070\pm 0.618$ | $0.766$ | $70$ | $14.5451\pm 0.0017$ |  |
K2-288 A | $14.2879\pm 0.0807$ | $187.057\pm 0.151$ | $-69.591\pm 0.116$ | $0.418$ | $41$ | $13.3090\pm 0.0009$ | $0.5668_{-0.0824}^{+0.0884}$ | SHC
HD 23472 A* | $25.5897\pm 0.0261$ | $-102.571\pm 0.050\,\,\,\,$ | $-43.917\pm 0.059$ | $-$ | $-$ | $\,\,\,9.3848\pm 0.0002$ | $0.0783_{-0.0703}^{+0.1742}$ |
HD 23472 B | $25.5060\pm 0.0732$ | $-103.019\pm 0.154\,\,\,\,$ | $-42.771\pm 0.169$ | $0.490$ | $16.1$ | $15.8312\pm 0.0014$ |  |
HD 24085 B* | $18.1859\pm 0.0245$ | $\,\,\,-9.249\pm 0.048$ | $-97.358\pm 0.050$ | $-$ | $-$ | $\,\,\,7.4250\pm 0.0002$ |  |
HD 24085 A | $18.1430\pm 0.0226$ | $-10.234\pm 0.043$ | $-97.151\pm 0.049$ | $-$ | $-$ | $\,\,\,7.2719\pm 0.0002$ | $0.6682_{-0.3903}^{+0.5911}$ |
HII 1348 A* (SB) |  $6.9890\pm 0.0490$ | $\,\,\,\,21.401\pm 0.120$ | $-45.705\pm 0.060$ | $-$ | $-$ | $12.2439\pm 0.0012$ |  |
HII 1348 C |  $6.6456\pm 0.1763$ | $\,\,\,\,20.250\pm 0.337$ | $-45.292\pm 0.235$ | $0.429$ | $4.1$ | $17.0303\pm 0.0017$ | $1.1810_{-0.3321}^{+0.3091}$ |
HII 1348 D |  $7.8946\pm 1.7831$ | $\,\,\,\,23.361\pm 4.630$ | $-42.219\pm 2.330$ | $2.369$ | $0.9$ | $20.7790\pm 0.0151$ | $0.6550_{-0.4581}^{+0.3718}$ |
HATS-57 A* |  $3.5495\pm 0.0392$ | $-12.664\pm 0.046$ | $-14.115\pm 0.040$ | $-$ | $-$ | $12.1816\pm 0.0007$ | $0.0548_{-0.0423}^{+0.1726}$ |
HATS-57 B |  $3.4904\pm 0.1265$ | $-12.064\pm 0.174$ | $-14.764\pm 0.142$ | $-$ | $-$ | $17.5558\pm 0.0012$ |  |
FU Tau A* |  $7.5981\pm 0.1497$ | $\,\,\,\,\,\,\,6.895\pm 0.376$ | $-21.026\pm 0.202$ | $0.732$ | $83$ | $15.2412\pm 0.0024$ | $2.2620_{-0.4841}^{+0.2597}$ |
FU Tau B |  $7.4909\pm 1.2887$ | $\,\,\,\,12.450\pm 4.056$ | $-21.761\pm 1.903$ | $3.516$ | $4.6$ | $20.4799\pm 0.0074$ |  |
DH Tau A* |  $7.3880\pm 0.0693$ | $\,\,\,\,\,\,\,7.065\pm 0.117$ | $-20.699\pm 0.079$ | $-$ | $-$ | $12.4961\pm 0.0090$ |  |
DH Tau C |  $7.4011\pm 0.0520$ | $\,\,\,\,\,\,\,6.899\pm 0.113$ | $-21.207\pm 0.074$ | $-$ | $-$ | $11.9692\pm 0.0013$ | $2.6683_{-0.1714}^{+0.3698}$ |
51 Eri A* | $33.5770\pm 0.1354$ | $\,\,\,\,44.352\pm 0.227$ | $-63.833\pm 0.178$ | $0.562$ | $190$ | $\,\,\,5.1224\pm 0.0017$ | $0.1740_{-0.1123}^{+0.2663}$ |
51 Eri B (SB) | $37.9633\pm 0.3662$ | $\,\,\,\,59.587\pm 0.717$ | $-52.419\pm 0.618$ | $1.958$ | $2030$ | $\,\,\,9.7247\pm 0.0011$ |  |
2M 0441+23 C* |  $8.3040\pm 0.3778$ | $\,\,\,\,\,\,\,8.955\pm 0.931$ | $-21.431\pm 0.456$ | $1.350$ | $5.7$ | $18.9668\pm 0.0068$ |  |
2M 0441+23 AB |  $8.0161\pm 0.0832$ | $\,\,\,\,\,\,\,8.300\pm 0.189$ | $-21.553\pm 0.103$ | $0.529$ | $79$ | $13.8267\pm 0.0011$ | $1.0577_{-0.4138}^{+0.9503}$ |

Table 2: continued Name | $\pi$ | $\mu_{\alpha}cos(\delta)$ | $\mu_{\delta}$ | $epsi$ |  $sig$- | G | $A_{G}$ |
---|---|---|---|---|---|---|---|---
| [mas] | [mas/yr] | [mas/yr] | [mas] | $epsi$ | [mag] | [mag] |
NGTS-6 A* | $\,\,\,3.2151\pm 0.0148$ | $\,\,\,-9.339\pm 0.025$ | $-21.9950\pm 0.026$ | $-$ | $-$ | $13.8175\pm 0.0006$ |  |
NGTS-6 B | $\,\,\,3.2231\pm 0.0653$ | $\,\,\,-9.301\pm 0.107$ | $-22.1300\pm 0.114$ | $0.203$ | $1.3$ | $17.0603\pm 0.0009$ | $0.3627_{-0.1403}^{+0.1024}$ |
AB Dor AC* | $65.3199\pm 0.1440$ | $\,\,\,\,29.150\pm 0.251$ | $\,\,164.4210\pm 0.299$ | $0.850$ | $317$ | $\,\,\,6.6738\pm 0.0018$ |  |
AB Dor BD | $67.0283\pm 0.0901$ | $\,\,\,\,66.366\pm 0.155$ | $\,\,125.8990\pm 0.189$ | $0.522$ | $111$ | $11.3560\pm 0.0012$ | $1.3528_{-0.4435}^{+0.5192}$ |
HD 39855 A* | $42.9636\pm 0.0346$ | $\,\,\,\,92.854\pm 0.046$ | $-24.4660\pm 0.063$ | $-$ | $-$ | $\,\,\,7.3211\pm 0.0002$ |  |
HD 39855 B | $42.9612\pm 0.0369$ | $\,\,\,\,96.166\pm 0.055$ | $-11.8960\pm 0.065$ | $-$ | $-$ | $10.0503\pm 0.0006$ | $0.1920_{-0.1257}^{+0.2268}$ |
NGTS-10 A* | $\,\,\,3.0798\pm 0.2610$ | $\,\,\,-2.323\pm 0.343$ | $\,\,\,\,10.5270\pm 0.395$ | $2.152$ | $1100$ | $14.2604\pm 0.0034$ |  |
NGTS-10 B | $\,\,\,0.2965\pm 0.0802$ | $\,\,\,-1.120\pm 0.219$ | $\,\,\,\,\,\,\,9.6710\pm 0.161$ | $0.064$ | $0.3$ | $15.5926\pm 0.0014$ | $0.7679_{-0.5770}^{+1.1986}$ | SHC
L2 Pup A* | $15.61\pm 0.99$ | $\,106.31\pm 0.96$ | $\,\,\,\,324.99\pm 1.08$ | $-$ | $-$ | $9.8208\pm 0.2812$ |  | HIP
L2 Pup B | $16.4131\pm 0.0574$ | $\,105.895\pm 0.097$ | $\,\,327.272\pm 0.099$ | $0.368$ | $12$ | $15.7099\pm 0.0009$ | $0.2940_{-0.0934}^{+0.3029}$ |
HIP 38594 A* | $56.1868\pm 0.0297$ | $-300.905\pm 0.044\,\,\,$ | $\,\,200.923\pm 0.045$ | $-$ | $-$ | $\,\,\,9.0853\pm 0.0003$ |  |
HIP 38594 B | $56.1234\pm 0.0799$ | $-297.867\pm 0.126\,\,\,$ | $\,\,206.598\pm 0.257$ | $-$ | $-$ | $16.0444\pm 0.0005$ | $0.3670_{-0.2630}^{+0.7758}$ |
WASP-180 A* | $\,\,\,3.9093\pm 0.0517$ | $-14.052\pm 0.091$ | $\,\,\,-3.169\pm 0.055$ | $-$ | $-$ | $10.9134\pm 0.0007$ |  |
WASP-180 B | $\,\,\,3.8618\pm 0.0734$ | $-12.705\pm 0.172$ | $\,\,\,-2.710\pm 0.103$ | $-$ | $-$ | $11.7712\pm 0.0008$ | $0.0930_{-0.0534}^{+0.1560}$ |
HD 79211 B* | $157.8851\pm 0.0414\,\,\,$ | $-1573.120\pm 0.061\,\,\,\,\,\,$ | $-660.121\pm 0.058\,\,\,\,$ | $-$ | $-$ | $\,\,\,7.0477\pm 0.0004$ |  |
HD 79211 A | $157.8796\pm 0.0366\,\,\,$ | $-1546.100\pm 0.059$ | $-569.127\pm 0.060\,\,\,\,$ | $-$ | $-$ | $\,\,\,6.9689\pm 0.0005$ | $0.3757_{-0.2078}^{+0.3264}$ |
HD 85628 A* | $\,\,\,5.8297\pm 0.0318$ | $\,\,\,\,\,\,\,6.051\pm 0.055$ | $-15.398\pm 0.051$ | $-$ | $-$ | $\,\,\,8.1740\pm 0.0004$ | $0.5012_{-0.2262}^{+0.1438}$ |
HD 85628 B | $\,\,\,5.9508\pm 0.0366$ | $\,\,\,\,\,\,\,5.856\pm 0.066$ | $-13.252\pm 0.060$ | $0.296$ | $18$ | $14.0490\pm 0.0047$ |  |
TOI 717 A* | $28.7709\pm 0.0783$ | $-26.092\pm 0.176$ | $\,\,\,\,62.064\pm 0.260$ | $0.045$ | $0.5$ | $12.6410\pm 0.0005$ | $0.3110_{-0.0211}^{+0.1274}$ |
TOI 717 B | $28.7588\pm 0.0824$ | $-23.995\pm 0.177$ | $\,\,\,\,62.081\pm 0.273$ | $0.060$ | $1.0$ | $12.7386\pm 0.0008$ |  |
G 196-3 A* | $45.8611\pm 0.0388$ | $-141.177\pm 0.055\,\,\,$ | $-202.394\pm 0.053\,\,\,\,$ | $0.000$ | $0.5$ | $10.6123\pm 0.0005$ | $1.0645_{-0.4836}^{+0.4919}$ |
G 196-3 B | $44.3549\pm 0.8128$ | $-137.820\pm 0.928\,\,\,$ | $-208.523\pm 1.671\,\,\,\,$ | $2.210$ | $3.3$ | $20.1697\pm 0.0085$ |  |
LTT 3780 A* | $45.4644\pm 0.0827$ | $-341.409\pm 0.114\,\,\,$ | $-247.870\pm 0.105\,\,\,\,$ | $0.137$ | $6.6$ | $11.8465\pm 0.0005$ | $0.5015_{-0.3436}^{+0.2595}$ |
LTT 3780 B | $45.2879\pm 0.1081$ | $-341.379\pm 0.149\,\,\,$ | $-248.419\pm 0.135\,\,\,\,$ | $0.414$ | $23$ | $14.4855\pm 0.0008$ |  |
MASCARA-3 A* | $10.3320\pm 0.0333$ | $-56.184\pm 0.053$ | $-34.808\pm 0.064$ | $-$ | $-$ | $\,\,\,8.2375\pm 0.0004$ | $0.2400_{-0.1150}^{+0.2740}$ |
MASCARA-3 B | $11.0260\pm 0.1268$ | $-50.757\pm 0.325$ | $-37.811\pm 0.200$ | $0.799$ | $160$ | $13.0002\pm 0.0109$ |  |
2M J1101-7732 A* | $\,\,\,5.4081\pm 0.1877$ | $-22.653\pm 0.435$ | $\,\,\,\,\,\,\,2.062\pm 0.397$ | $1.271$ | $12$ | $18.3299\pm 0.0023$ |  |
2M J1101-7732 B | $\,\,\,5.4333\pm 0.3368$ | $-23.668\pm 0.748$ | $\,\,\,\,\,\,\,1.931\pm 0.723$ | $1.836$ | $6.1$ | $19.4040\pm 0.0047$ | $0.5900_{-0.1200}^{+0.1200}$ | ✠
WASP-175 A* | $\,\,\,1.8260\pm 0.0399$ | $-24.306\pm 0.057$ | $\,\,\,\,\,\,\,6.033\pm 0.057$ | $-$ | $-$ | $12.7065\pm 0.0002$ |  |
WASP-175 B | $\,\,\,1.7947\pm 0.0308$ | $-24.064\pm 0.045$ | $\,\,\,\,\,\,\,6.185\pm 0.045$ | $-$ | $-$ | $14.2462\pm 0.0003$ | $0.0965_{-0.0876}^{+0.0966}$ |

Table 2: continued Name | $\pi$ | $\mu_{\alpha}cos(\delta)$ | $\mu_{\delta}$ | $epsi$ |  $sig$- | G | $A_{G}$ |
---|---|---|---|---|---|---|---|---
| [mas] | [mas/yr] | [mas/yr] | [mas] | $epsi$ | [mag] | [mag] |
CHXR 73 A* | $\,\,\,5.2343\pm 0.1759$ | $-22.193\pm 0.233$ | $\,\,\,\,\,\,\,0.215\pm 0.206$ | $0.815$ | $12$ | $17.2934\pm 0.0014$ | $3.4650_{-1.0250}^{+1.0250}$ | $\maltese$
CHXR 73 C | $\,\,\,5.2502\pm 0.2218$ | $-22.937\pm 0.433$ | $\,\,\,-1.261\pm 0.347$ | $1.241$ | $14$ | $17.9098\pm 0.0021$ |  |
GJ 414 A* | $84.0803\pm 0.0471$ | $\,\,591.622\pm 0.081$ | $-197.247\pm 0.091\,\,\,\,$ | $-$ | $-$ | $\,\,\,7.7281\pm 0.0007$ |  |
GJ 414 B | $84.1971\pm 0.0579$ | $\,\,604.831\pm 0.081$ | $-206.442\pm 0.075\,\,\,\,$ | $-$ | $-$ | $\,\,\,9.0471\pm 0.0011$ | $0.6100_{-0.3221}^{+0.5656}$ |
HD 97334 A* | $44.1428\pm 0.0383$ | $-249.387\pm 0.090\,\,\,$ | $-151.590\pm 0.071\,\,\,\,$ | $-$ | $-$ | $\,\,\,6.2410\pm 0.0006$ | $0.0555_{-0.0415}^{+0.1848}$ |
HD 97334 BC | $42.8724\pm 1.1025$ | $-236.349\pm 2.133\,\,\,$ | $-152.068\pm 2.109\,\,\,\,$ | $5.342$ | $15$ | $19.9859\pm 0.0135$ |  |
HD 233832 A* | $16.9952\pm 0.0752$ | $-473.960\pm 0.075\,\,\,$ | $124.167\pm 0.087$ | $-$ | $-$ | $\,\,\,9.9456\pm 0.0005$ |  |
HD 233832 B | $17.0667\pm 0.0532$ | $-478.645\pm 0.048\,\,\,$ | $119.122\pm 0.088$ | $-$ | $-$ | $12.7187\pm 0.0004$ | $0.2288_{-0.1079}^{+0.2054}$ |
2M J1155-7919 A* | $\,\,\,9.8862\pm 0.0585$ | $-41.179\pm 0.127$ | $\,\,\,-4.336\pm 0.086$ | $0.490$ | $35$ | $14.8180\pm 0.0017$ | $0.4158_{-0.0052}^{+0.0616}$ | $\maltese$
2M J1155-7919 B | $\,\,\,9.8211\pm 0.5264$ | $-39.738\pm 1.216$ | $\,\,\,-4.656\pm 0.687$ | $1.387$ | $1.4$ | $19.9246\pm 0.0079$ |  |
NGTS-5 A* | $\,\,\,3.2310\pm 0.0272$ | $\,\,\,\,13.650\pm 0.041$ | $\,\,\,-4.688\pm 0.042$ | $-$ | $-$ | $13.5260\pm 0.0004$ | $0.1970_{-0.1174}^{+0.1050}$ |
NGTS-5 B | $\,\,\,2.9428\pm 0.1254$ | $\,\,\,\,13.938\pm 0.209$ | $\,\,\,-4.331\pm 0.180$ | $0.422$ | $3.0$ | $17.3160\pm 0.0016$ |  |
2M J1450-7841 A* | $10.9480\pm 0.5046$ | $-37.597\pm 0.881$ | $-23.654\pm 0.895$ | $2.345$ | $5.0$ | $19.6858\pm 0.0060$ | $0.5000_{-0.5000}^{+0.5000}$ | ✠
2M J1450-7841 B | $\,\,\,8.6592\pm 0.9023$ | $-34.984\pm 2.047$ | $-22.162\pm 1.764$ | $2.067$ | $1.1$ | $20.6501\pm 0.0097$ |  |
WASP-189 A* | $\,\,\,9.9990\pm 0.0747$ | $-50.564\pm 0.109$ | $-23.788\pm 0.115$ | $0.082$ | $2.2$ | $\,\,\,6.5537\pm 0.0004$ | $0.2652_{-0.2306}^{+0.1599}$ | SHC
WASP-189 B | $10.7202\pm 0.1648$ | $-50.594\pm 0.165$ | $-24.037\pm 0.178$ | $0.475$ | $25$ | $14.3874\pm 0.0024$ |  |
HIP 73990 A* | $\,\,\,9.0326\pm 0.0648$ | $-27.432\pm 0.106$ | $-29.028\pm 0.089$ | $-$ | $-$ | $\,\,\,8.0678\pm 0.0009$ |  |
HIP 73990 D | $\,\,\,8.9507\pm 0.0899$ | $-27.728\pm 0.159$ | $-29.245\pm 0.135$ | $0.457$ | $28$ | $14.6580\pm 0.0007$ | $1.1073_{-0.4489}^{+0.6427}$ |
TOI 905 A* | $\,\,\,6.2745\pm 0.0285$ | $-25.839\pm 0.033$ | $-41.150\pm 0.051$ | $-$ | $-$ | $11.0813\pm 0.0004$ | $0.2703_{-0.1606}^{+0.1330}$ | SHC
TOI 905 B | $\,\,\,7.8542\pm 0.5489$ | $-18.290\pm 0.763$ | $-39.819\pm 0.788$ | $1.423$ | $25$ | $17.2149\pm 0.0375$ |  |
2M 1510 A* | $27.2203\pm 0.2665$ | $-118.747\pm 0.492\,\,\,$ | $-46.865\pm 0.420$ | $1.112$ | $18$ | $17.4870\pm 0.0018$ | $0.9266_{-0.0121}^{+0.1360}$ | SHC
2M 1510 B | $27.6869\pm 0.4939$ | $-117.448\pm 0.893\,\,\,$ | $-45.713\pm 0.746$ | $1.710$ | $7.8$ | $18.8855\pm 0.0035$ |  |
$\beta$ Cir A* | $35.1736\pm 0.4253$ | $-96.742\pm 0.491$ | $-136.541\pm 0.621\,\,\,\,$ | $1.852$ | $1770$ | $\,\,\,3.9732\pm 0.0026$ | $0.2560_{-0.1598}^{+0.2260}$ |
$\beta$ Cir B | $34.7836\pm 0.6840$ | $-92.763\pm 0.829$ | $-138.156\pm 1.469\,\,\,\,$ | $2.701$ | $15$ | $19.4335\pm 0.0051$ |  |
KELT-23 A* | $\,\,\,7.8912\pm 0.0219$ | $\,\,\,\,\,\,\,0.434\pm 0.039$ | $-12.217\pm 0.041$ | $-$ | $-$ | $10.1820\pm 0.0004$ | $0.0680_{-0.0505}^{+0.0996}$ |
KELT-23 B | $\,\,\,7.8949\pm 0.0529$ | $\,\,\,\,\,\,\,1.567\pm 0.093$ | $-11.903\pm 0.107$ | $0.284$ | $6.8$ | $15.5209\pm 0.0014$ |  |
K2-290 A*B | $\,\,\,3.6365\pm 0.0503$ | $\,\,\,\,27.225\pm 0.099$ | $-16.893\pm 0.066$ | $-$ | $-$ | $10.8204\pm 0.0004$ | $0.8900_{-0.2655}^{+0.2570}$ |
K2-290 C | $\,\,\,4.0531\pm 0.2711$ | $\,\,\,\,27.465\pm 0.593$ | $-16.484\pm 0.370$ | $0.556$ | $1.2$ | $18.5920\pm 0.0027$ |  |
GQ Lup A* | $\,\,\,6.5868\pm 0.0473$ | $-14.257\pm 0.097$ | $-23.596\pm 0.066$ | $0.110$ | $5.7$ | $11.2608\pm 0.0089$ | $2.7645_{-0.4140}^{+0.3426}$ |
GQ Lup C | $\,\,\,5.4925\pm 0.4597$ | $-14.807\pm 0.972$ | $-21.947\pm 0.653$ | $2.960$ | $59$ | $18.3740\pm 0.0037$ |  |

Table 2: continued Name | $\pi$ | $\mu_{\alpha}cos(\delta)$ | $\mu_{\delta}$ | $epsi$ |  $sig$- | G | $A_{G}$ |
---|---|---|---|---|---|---|---|---
| [mas] | [mas/yr] | [mas/yr] | [mas] | $epsi$ | [mag] | [mag] |
HIP 77900 A* | $\,\,\,6.6037\pm 0.1196$ | $-13.357\pm 0.187$ | $-25.272\pm 0.110$ | $0.212$ | $21$ | $\,\,\,6.1129\pm 0.0006$ | $0.1852_{-0.0360}^{+0.1535}$ |
HIP 77900 B | $\,\,\,5.2279\pm 0.9696$ | $-13.908\pm 1.517$ | $-23.265\pm 1.097$ | $2.007$ | $4.3$ | $19.5660\pm 0.0057$ |  |
USco 1602-2401 A* | $\,\,\,6.9484\pm 0.0661$ | $-11.850\pm 0.119$ | $-24.032\pm 0.051$ | $-$ | $-$ | $11.8656\pm 0.0026$ | $1.8885_{-0.1186}^{+0.1123}$ | SHC
USco 1602-2401 B | $\,\,\,6.3381\pm 0.2030$ | $-12.699\pm 0.325$ | $-23.872\pm 0.187$ | $0.829$ | $40$ | $16.3640\pm 0.0010$ |  |
HIP 79098 A (SB)* | $\,\,\,6.8337\pm 0.1176$ | $\,\,\,-9.823\pm 0.210$ | $-28.119\pm 0.163$ | $0.289$ | $35$ | $\,\,\,5.8264\pm 0.0006$ | $0.4640_{-0.2381}^{+0.1440}$ |
HIP 79098 C | $\,\,\,7.1870\pm 0.1476$ | $-10.979\pm 0.271$ | $-26.128\pm 0.189$ | $0.666$ | $27$ | $16.1091\pm 0.0012$ |  |
USco 1610-1913 A* | $\,\,\,7.4960\pm 0.0718$ | $\,\,\,-9.342\pm 0.206$ | $-23.591\pm 0.111$ | $0.168$ | $12$ | $12.6962\pm 0.0049$ | $0.3850_{-0.3850}^{+0.3850}$ | $\maltese$
USco 1610-1913 B | $\,\,\,6.9600\pm 0.3719$ | $\,\,\,-7.043\pm 1.112$ | $-24.982\pm 0.576$ | $1.301$ | $7.0$ | $18.7225\pm 0.0029$ |  |
USco 1612-1800 A* | $\,\,\,6.3156\pm 0.0747$ | $\,\,\,-7.418\pm 0.161$ | $-21.148\pm 0.112$ | $0.427$ | $31$ | $14.5532\pm 0.0007$ | $0.3850_{-0.3850}^{+0.3850}$ | $\maltese$
USco 1612-1800 B | $\,\,\,6.0413\pm 0.3224$ | $\,\,\,-7.002\pm 0.698$ | $-19.738\pm 0.512$ | $1.112$ | $4.0$ | $18.8810\pm 0.0032$ |  |
ROXs 12 A* | $\,\,\,7.2894\pm 0.0417$ | $\,\,\,-7.185\pm 0.090$ | $-24.851\pm 0.059$ | $0.158$ | $6.9$ | $13.2655\pm 0.0013$ | $1.8000_{-1.0000}^{+1.0000}$ | $\maltese$
ROXs 12 C | $\,\,\,7.2328\pm 0.0738$ | $\,\,\,-6.577\pm 0.151$ | $-25.106\pm 0.099$ | $0.354$ | $20$ | $14.7659\pm 0.0113$ |  |
HATS-48 A* | $\,\,\,3.7648\pm 0.0237$ | $\,\,\,\,\,\,\,3.125\pm 0.031$ | $\,\,\,\,\,\,\,6.146\pm 0.029$ | $-$ | $-$ | $13.8951\pm 0.0002$ | $0.5090_{-0.3705}^{+0.1876}$ |
HATS-48 B | $\,\,\,3.6354\pm 0.4432$ | $\,\,\,\,\,\,\,2.951\pm 0.469$ | $\,\,\,\,\,\,\,5.201\pm 0.446$ | $0.576$ | $0.6$ | $19.3368\pm 0.0037$ |  |
GJ 752 A* | $169.1590\pm 0.0520\,\,\,$ | $-579.043\pm 0.088\,\,\,$ | $-1332.740\pm 0.081\,\,\,\,\,\,\,$ | $-$ | $-$ | $\,\,\,8.0976\pm 0.0011$ |  |
GJ 752 B | $168.9620\pm 0.1299\,\,\,$ | $-598.177\pm 0.245\,\,\,$ | $-1365.270\pm 0.227\,\,\,\,\,\,$ | $0.855$ | $98$ | $14.3212\pm 0.0007$ | $1.4208_{-0.1719}^{+0.2795}$ |
HD 181234 A* | $20.9155\pm 0.0564$ | $-122.751\pm 0.098\,\,\,$ | $-318.277\pm 0.098\,\,\,\,$ | $-$ | $-$ | $\,\,\,8.3693\pm 0.0004$ | $0.3670_{-0.0723}^{+0.1987}$ |
HD 181234 B | $20.8683\pm 0.1458$ | $-117.558\pm 0.192\,\,\,$ | $-323.292\pm 0.211\,\,\,\,$ | $0.520$ | $27$ | $14.2207\pm 0.0012$ |  |
Wendelstein-1 A* | $\,\,\,3.2470\pm 0.0317$ | $\,\,\,\,\,\,\,4.131\pm 0.041$ | $\,\,\,-1.832\pm 0.039$ | $-$ | $-$ | $15.0324\pm 0.0005$ | $0.5240_{-0.4315}^{+0.4730}$ |
Wendelstein-1 B | $\,\,\,3.5833\pm 0.4053$ | $\,\,\,\,\,\,\,3.862\pm 0.508$ | $\,\,\,-2.194\pm 0.536$ | $1.038$ | $1.9$ | $19.3979\pm 0.0031$ |  |
2M J2126-81 A* | $29.2836\pm 0.0690$ | $\,\,\,\,59.843\pm 0.111$ | $-107.723\pm 0.114\,\,\,\,$ | $0.303$ | $48$ | $10.8133\pm 0.0021$ | $0.2157_{-0.0470}^{+0.4319}$ | SHC
2M J2126-81 B | $29.2463\pm 0.9205$ | $\,\,\,\,56.511\pm 1.656$ | $-115.369\pm 2.441$ | $4.299$ | $4.4$ | $20.7247\pm 0.0094$ |  |
TOI 132 A* | $\,\,\,6.0809\pm 0.0366$ | $\,\,\,\,35.553\pm 0.043$ | $-53.055\pm 0.054$ | $0.090$ | $3.6$ | $11.3208\pm 0.0007$ | $0.1535_{-0.1430}^{+0.1606}$ |
TOI 132 B | $\,\,\,5.9683\pm 0.2251$ | $\,\,\,\,35.417\pm 0.280$ | $-52.488\pm 0.361$ | $0.955$ | $7.4$ | $18.4470\pm 0.0015$ |  |
NGTS-7 A* | $\,\,\,7.2497\pm 0.1203$ | $-27.003\pm 0.114$ | $-16.225\pm 0.178$ | $0.610$ | $72$ | $14.9154\pm 0.0020$ | $0.5000_{-0.5000}^{+0.5000}$ | $\maltese$
NGTS-7 B | $\,\,\,6.5232\pm 0.0787$ | $-28.601\pm 0.112$ | $-14.776\pm 0.364$ | $0.203$ | $4.4$ | $15.5134\pm 0.0012$ |  |
DS Tuc A* | $22.6663\pm 0.0354$ | $\,\,\,\,79.464\pm 0.074$ | $-67.440\pm 0.045$ | $-$ | $-$ | $\,\,\,8.3193\pm 0.0010$ |  |
DS Tuc B | $22.6504\pm 0.0297$ | $\,\,\,\,78.022\pm 0.064$ | $-65.746\pm 0.037$ | $-$ | $-$ | $\,\,\,9.3993\pm 0.0014$ | $0.3210_{-0.1034}^{+0.2350}$ |
1RXS J2351+3127 A* | $23.2183\pm 0.0524$ | $\,\,106.584\pm 0.064$ | $-87.761\pm 0.038$ | $0.083$ | $3.9$ | $12.5145\pm 0.0005$ |  |
1RXS J2351+3127 C | $23.1794\pm 0.0592$ | $\,\,105.757\pm 0.070$ | $-87.787\pm 0.041$ | $0.285$ | $32$ | $13.2004\pm 0.0006$ | $0.4190_{-0.0410}^{+0.4250}$ |

Comments on individual objects:

  * •

HD 1160 A hosts a brown dwarf companion (HD 1160 B, detected by Nielsen et
al., 2012), which is listed as exoplanet in the EPE.

  * •

The exoplanet host star HD 24085 B is the secondary component of a binary
system, whose primary star HD 24085 A is also known as HD 24062.

  * •

HII 1348 A is a spectroscopic binary with a brown dwarf companion (HII 1348 B,
discovered by Geißler et al., 2012), which is listed as exoplanet in the EPE.

  * •

DH Tau A hosts a brown dwarf companion (DH Tau B), which was detected by Itoh
et al. (2005) and is listed as exoplanet in the EPE. DH Tau C (alias DI Tau)
is the wide primary component of this system.

  * •

2M 0441+23 C is an exoplanet host brown dwarf (Bowler and Hillenbrand, 2015),
which is listed in the EPE.

  * •

The bright AGB star L2 Pup A is listed in the Gaia DR2 but with a parallax
($\pi=7.3644\pm 0.6149$ mas) that significantly differs from its HIPPARCOS-
value ($\pi=15.61\pm 0.99$ mas, van Leeuwen, 2007). Furthermore, it should be
noted that the G-band brightness of this star, as listed in the Gaia DR2, is
several magnitudes fainter than expected (e.g. $G=3.97\pm 0.54$ mag, as
estimated by Smart and Nicastro, 2014). Therefore, we only use here the Gaia
DR2 equatorial coordinates of this star, while we adopt the HIPPARCOS-values
of its parallax and proper motion, which is indicated with the flag HIP in
this table.

  * •

HIP 73990 A is the host star of two brown dwarfs (HIP 73990 B & C, revealed by
Hinkley et al., 2015), which are both listed as exoplanets in the EPE.

  * •

GQ Lup A is listed as exoplanet host star in the EPE, whose substellar
companion was detected by Neuhäuser et al. (2005). The star exhibits a wide
stellar companion, whose WDS designation (GQ Lup C) is used here.

  * •

HIP 79098 A is a spectroscopic binary and hosts the brown dwarf HIP 79098 B
(Janson et al., 2019), which is listed as exoplanet in the EPE.

  * •

ROXs 12 A is the host star of the brown dwarf ROXs 12 B, detected by Kraus et
al. (2014), which is listed as exoplanet in the EPE.

  * •

RXSJ2351+3127 A hosts a brown dwarf companion (RXSJ2351+3127 B, discovered by
Bowler et al., 2012), which is listed as exoplanet in the EPE.

  * •

HII 1348 A, FU Tau A, G 196-3 A, 2M J1155-7919 A, HD 97334 A, $\beta$ Cir A,
HIP 77900 A, USco 1602-2401 A, USco 1610-1913 A, USco 1612-1800 A, and 2M
J2126-81 A, are all listed as exoplanet host stars in the EPE, whose
substellar companions were detected and characterized in this study, using
data from the Gaia DR2.

  * •

2M J1101-7732 A, 2M J1450-7841 A, 2M 1510 A are all brown dwarfs, which are
listed as exoplanet hosts in the EPE, whose substellar companions were
detected and characterized in this study with Gaia DR2 data.

Table 3: The relative astrometry and WDS status of all detected companions. Companion | $\rho$ | $PA$ | $\Delta\pi$ |  $sig$- | $\mu_{rel}$ |  $sig$- |  $cpm$- | not in
---|---|---|---|---|---|---|---|---
| [arcsec] | [∘] | [mas] | $\Delta\pi$ | [mas/yr] | $\mu_{rel}$ | $index$ | WDS
HD 1160 C | $5.14549\pm 0.00018$ | $349.53223\pm 0.00259$ | $0.95\pm 0.28$ | $3.3~{}(1.2)$ | $1.72\pm 0.33$ | $5.2$ | $30$ |
Gliese 49 B | $294.45989\pm 0.00011\,\,\,\,\,\,$ | $\,\,\,75.52728\pm 0.00002$ | $0.17\pm 0.09$ | $2.0~{}(0.8)$ | $4.36\pm 0.23$ | $19$ | $338$ |
HD 8326 B | $56.88131\pm 0.00005\,\,\,$ | $147.16909\pm 0.00006$ | $0.12\pm 0.08$ | $1.6~{}(0.3)$ | $1.18\pm 0.17$ | $7.1$ | $394$ |
HD 13167 B | $20.06421\pm 0.00010\,\,\,$ | $\,\,\,24.77589\pm 0.00028$ | $0.11\pm 0.13$ | $0.8~{}(0.2)$ | $1.28\pm 0.23$ | $5.7$ | $91$ | $\bigstar~{}~{}~{}~{}$
HR 858 B | $8.35742\pm 0.00013$ | $\,\,\,15.79337\pm 0.00060$ | $1.04\pm 0.18$ | $5.8~{}(1.2)$ | $13.90\pm 0.22\,\,\,$ | $62$ | $24$ | $\bigstar^{1}~{}~{}$
HD 18015 B | $7.08916\pm 0.00006$ | $316.16832\pm 0.00045$ | $0.11\pm 0.07$ | $1.6~{}(1.6)$ | $1.61\pm 0.11$ | $14$ | $79$ |
K2-288 A | $0.78692\pm 0.00018$ | $340.38240\pm 0.01437$ | $0.93\pm 0.22$ | $4.3~{}(1.0)$ | $4.75\pm 0.64$ | $7.4$ | $84$ | $\bigstar^{2}~{}~{}$
HD 23472 B | $9.56924\pm 0.00008$ | $\,\,\,45.28294\pm 0.00046$ | $0.08\pm 0.08$ | $1.1~{}(0.2)$ | $1.23\pm 0.18$ | $7.0$ | $181$ | $\bigstar~{}~{}~{}~{}$
HD 24085 A | $75.91260\pm 0.00003\,\,\,$ | $263.05666\pm 0.00002$ | $0.04\pm 0.03$ | $1.3~{}(1.3)$ | $1.01\pm 0.06$ | $16$ | $194$ | $\bigstar~{}~{}~{}~{}$
HII 1348 C | $36.02849\pm 0.00016\,\,\,$ | $276.87735\pm 0.00017$ | $0.34\pm 0.18$ | $1.9~{}(0.7)$ | $1.22\pm 0.35$ | $3.5$ | $82$ | $\bigstar~{}~{}~{}~{}$
HII 1348 D | $55.01726\pm 0.00090\,\,\,$ | $182.06892\pm 0.00182$ | $0.91\pm 1.78$ | $0.5~{}(0.3)$ | $4.00\pm 3.05$ | $1.3$ | $25$ | $\bigstar~{}~{}~{}~{}$
HATS-57 B | $14.44086\pm 0.00010\,\,\,$ | $282.25351\pm 0.00032$ | $0.06\pm 0.13$ | $0.4~{}(0.4)$ | $0.88\pm 0.16$ | $5.4$ | $43$ | $\bigstar~{}~{}~{}~{}$
FU Tau B | $5.68952\pm 0.00112$ | $123.57637\pm 0.00858$ | $0.11\pm 1.30$ | $0.1~{}(0.0)$ | $5.60\pm 4.05$ | $1.4$ | $8$ |
DH Tau C | $15.29981\pm 0.00007\,\,\,$ | $126.08805\pm 0.00023$ | $0.01\pm 0.09$ | $0.2~{}(0.2)$ | $0.53\pm 0.11$ | $4.7$ | $83$ |
51 Eri B (SB) | $66.96749\pm 0.00027\,\,\,$ | $162.62918\pm 0.00028$ | $4.39\pm 0.39$ | $11.2~{}(2.1)\,\,$ | $19.04\pm 0.71\,\,\,$ | $27$ | $8$ |
2M 0441+23 AB | $12.31449\pm 0.00036\,\,\,$ | $\,\,\,57.55273\pm 0.00133$ | $0.29\pm 0.39$ | $0.7~{}(0.2)$ | $0.67\pm 0.94$ | $0.7$ | $70$ |
NGTS-6 B | $5.36108\pm 0.00005$ | $116.68846\pm 0.00060$ | $0.01\pm 0.07$ | $0.1~{}(0.0)$ | $0.14\pm 0.12$ | $1.2$ | $342$ | $\bigstar~{}~{}~{}~{}$
AB Dor BD | $8.87930\pm 0.00018$ | $347.19358\pm 0.00097$ | $1.71\pm 0.17$ | $10.1~{}(1.7)\,\,$ | $53.56\pm 0.33\,\,\,$ | $164$ | $6$ |
HD 39855 B | $10.72622\pm 0.00004\,\,\,$ | $\,\,\,19.55064\pm 0.00017$ | $0.00\pm 0.05$ | $0.0~{}(0.0)$ | $13.00\pm 0.09\,\,\,$ | $145$ | $15$ |
NGTS-10 B | $1.12234\pm 0.00023$ | $334.73644\pm 0.01107$ | $2.78\pm 0.27$ | $10.2~{}(1.3)\,\,$ | $1.48\pm 0.41$ | $3.6$ | $14$ | $\bigstar^{3}~{}~{}$
L2 Pup B | $32.80132\pm 0.00052\,\,\,$ | $\,\,\,63.66528\pm 0.00099$ | $0.80\pm 0.99$ | $0.8\,\,\,~{}(-)$ | $2.32\pm 1.08$ | $2.2$ | $296$ | $\bigstar~{}~{}~{}~{}$
HIP 38594 B | $399.81589\pm 0.00012\,\,\,\,\,\,$ | $208.91546\pm 0.00001$ | $0.06\pm 0.09$ | $0.7~{}(0.7)$ | $6.44\pm 0.24$ | $27$ | $113$ |
WASP-180 B | $4.86185\pm 0.00006$ | $138.92126\pm 0.00081$ | $0.05\pm 0.09$ | $0.5~{}(0.5)$ | $1.42\pm 0.19$ | $7.6$ | $19$ |
HD 79211 A | $17.08255\pm 0.00004\,\,\,$ | $277.72812\pm 0.00014$ | $0.01\pm 0.06$ | $0.1~{}(0.1)$ | $94.92\pm 0.08\,\,\,$ | $1136$ | $35$ |
HD 85628 B | $4.33622\pm 0.00004$ | $224.93946\pm 0.00056$ | $0.12\pm 0.05$ | $2.5~{}(0.4)$ | $2.15\pm 0.08$ | $27$ | $14$ | $\bigstar^{4}~{}~{}$
TOI 717 B | $65.46692\pm 0.00016\,\,\,$ | $\,\,\,88.63021\pm 0.00020$ | $0.01\pm 0.11$ | $0.1~{}(0.1)$ | $2.10\pm 0.25$ | $8.4$ | $64$ |
G 196-3 B | $16.06941\pm 0.00055\,\,\,$ | $209.15563\pm 0.00166$ | $1.51\pm 0.81$ | $1.9~{}(0.6)$ | $6.99\pm 1.53$ | $4.6$ | $71$ |
LTT 3780 B | $15.78849\pm 0.00011\,\,\,$ | $\,\,\,97.14133\pm 0.00038$ | $0.18\pm 0.14$ | $1.3~{}(0.4)$ | $0.55\pm 0.17$ | $3.2$ | $1535$ |
MASCARA-3 B | $2.06449\pm 0.00010$ | $173.15273\pm 0.00345$ | $0.69\pm 0.13$ | $5.3~{}(0.9)$ | $6.20\pm 0.31$ | $20$ | $21$ | $\bigstar^{5}~{}~{}$
2M J1101-7732 B | $1.42656\pm 0.00041$ | $\,\,\,30.00553\pm 0.01621$ | $0.03\pm 0.39$ | $0.1~{}(0.0)$ | $1.02\pm 0.86$ | $1.2$ | $45$ |
WASP-175 B | $7.25020\pm 0.00003$ | $\,\,\,\,\,\,4.95541\pm 0.00027$ | $0.03\pm 0.05$ | $0.6~{}(0.6)$ | $0.29\pm 0.07$ | $3.9$ | $175$ | $\bigstar^{6}~{}~{}$

Table 3: continued Companion | $\rho$ | $PA$ | $\Delta\pi$ |  $sig$- | $\mu_{rel}$ |  $sig$- |  $cpm$- | not in
---|---|---|---|---|---|---|---|---
| [arcsec] | [∘] | [mas] | $\Delta\pi$ | [mas/yr] | $\mu_{rel}$ | $index$ | WDS
CHXR 73 C | $46.10344\pm 0.00027\,\,\,$ | $248.30821\pm 0.00031$ | $0.02\pm 0.28$ | $0.1~{}(0.0)$ | $1.65\pm 0.42$ | $3.9$ | $27$ | $\bigstar~{}~{}~{}~{}$
GJ 414 B | $34.15873\pm 0.00007\,\,\,$ | $262.44625\pm 0.00011$ | $0.12\pm 0.07$ | $1.6~{}(1.6)$ | $16.09\pm 0.12\,\,\,$ | $139$ | $78$ |
HD 97334 BC | $89.88421\pm 0.00098\,\,\,$ | $245.04583\pm 0.00060$ | $1.27\pm 1.10$ | $1.2~{}(0.2)$ | $13.05\pm 2.13\,\,\,$ | $6.1$ | $44$ |
HD 233832 B | $4.93691\pm 0.00004$ | $266.38672\pm 0.00079$ | $0.07\pm 0.09$ | $0.8~{}(0.8)$ | $6.88\pm 0.11$ | $63$ | $143$ |
2M J1155-7919 B | $5.75435\pm 0.00047$ | $227.86140\pm 0.00458$ | $0.07\pm 0.53$ | $0.1~{}(0.0)$ | $1.48\pm 1.20$ | $1.2$ | $55$ | $\bigstar^{7}~{}~{}$
NGTS-5 B | $26.89147\pm 0.00011\,\,\,$ | $116.31597\pm 0.00021$ | $0.29\pm 0.13$ | $2.2~{}(0.7)$ | $0.46\pm 0.20$ | $2.3$ | $63$ | $\bigstar~{}~{}~{}~{}$
2M J1450-7841 B | $4.23901\pm 0.00099$ | $313.26065\pm 0.01318$ | $2.29\pm 1.03$ | $2.2~{}(0.7)$ | $3.01\pm 2.17$ | $1.4$ | $29$ | $\bigstar^{8}~{}~{}$
WASP-189 B | $9.41610\pm 0.00010$ | $\,\,\,70.78901\pm 0.00095$ | $0.72\pm 0.18$ | $4.0~{}(1.4)$ | $0.25\pm 0.21$ | $1.2$ | $446$ | $\bigstar~{}~{}~{}~{}$
HIP 73990 D | $47.27427\pm 0.00009\,\,\,$ | $\,\,\,56.65125\pm 0.00010$ | $0.08\pm 0.11$ | $0.7~{}(0.2)$ | $0.37\pm 0.18$ | $2.0$ | $219$ | $\bigstar~{}~{}~{}~{}$
TOI 905 B | $2.24803\pm 0.00050$ | $100.34253\pm 0.01658$ | $1.58\pm 0.55$ | $2.9~{}(1.0)$ | $7.67\pm 0.76$ | $10$ | $12$ |
2M 1510 B | $6.77139\pm 0.00046$ | $209.28499\pm 0.00431$ | $0.47\pm 0.56$ | $0.8~{}(0.2)$ | $1.74\pm 0.95$ | $1.8$ | $146$ | $\bigstar^{9}~{}~{}$
$\beta$ Cir B | $217.62247\pm 0.00055\,\,\,\,\,\,$ | $199.25875\pm 0.00013$ | $0.39\pm 0.81$ | $0.5~{}(0.1)$ | $4.29\pm 1.08$ | $4.0$ | $78$ |
KELT-23 B | $4.54135\pm 0.00006$ | $127.68919\pm 0.00069$ | $0.00\pm 0.06$ | $0.1~{}(0.0)$ | $1.18\pm 0.10$ | $12$ | $21$ | $\bigstar^{10}$
K2-290 C | $11.25119\pm 0.00017\,\,\,$ | $179.97609\pm 0.00151$ | $0.42\pm 0.28$ | $1.5~{}(0.7)$ | $0.47\pm 0.44$ | $1.1$ | $135$ | $\bigstar^{11}$
GQ Lup C | $16.11286\pm 0.00039\,\,\,$ | $114.61327\pm 0.00099$ | $1.09\pm 0.46$ | $2.4~{}(0.4)$ | $1.74\pm 0.70$ | $2.5$ | $31$ |
HIP 77900 B | $22.27990\pm 0.00044\,\,\,$ | $\,\,\,12.74996\pm 0.00267$ | $1.38\pm 0.98$ | $1.4~{}(0.6)$ | $2.08\pm 1.14$ | $1.8$ | $27$ | $\bigstar^{12}$
USco 1602-2401 B | $7.21512\pm 0.00008$ | $353.20771\pm 0.00157$ | $0.61\pm 0.21$ | $2.9~{}(0.7)$ | $0.86\pm 0.34$ | $2.5$ | $62$ |
HIP 79098 C | $65.29721\pm 0.00018\,\,\,$ | $101.86730\pm 0.00008$ | $0.35\pm 0.19$ | $1.9~{}(0.5)$ | $2.30\pm 0.28$ | $8.3$ | $25$ | $\bigstar^{13}$
USco 1610-1913 B | $5.82725\pm 0.00040$ | $113.57990\pm 0.00238$ | $0.54\pm 0.38$ | $1.4~{}(0.4)$ | $2.69\pm 1.01$ | $2.7$ | $19$ |
USco 1612-1800 B | $3.18438\pm 0.00019$ | $\,\,\,10.65437\pm 0.00561$ | $0.27\pm 0.33$ | $0.8~{}(0.2)$ | $1.47\pm 0.54$ | $2.7$ | $29$ | $\bigstar^{14}$
ROXs 12 C | $37.14026\pm 0.00004\,\,\,$ | $185.99483\pm 0.00012$ | $0.06\pm 0.08$ | $0.7~{}(0.1)$ | $0.66\pm 0.17$ | $3.9$ | $79$ | $\bigstar^{15}$
HATS-48 B | $5.43813\pm 0.00025$ | $267.59024\pm 0.00322$ | $0.13\pm 0.44$ | $0.3~{}(0.2)$ | $0.96\pm 0.45$ | $2.2$ | $13$ | $\bigstar^{16}$
GJ 752 B | $75.48951\pm 0.00011\,\,\,$ | $152.49075\pm 0.00009$ | $0.20\pm 0.14$ | $1.4~{}(0.2)$ | $37.74\pm 0.25\,\,\,$ | $153$ | $78$ |
HD 181234 B | $5.17023\pm 0.00011$ | $\,\,\,56.61253\pm 0.00118$ | $0.05\pm 0.16$ | $0.3~{}(0.1)$ | $7.22\pm 0.22$ | $32$ | $95$ |
Wendelstein-1 B | $11.79208\pm 0.00024\,\,\,$ | $232.62838\pm 0.00116$ | $0.34\pm 0.41$ | $0.8~{}(0.3)$ | $0.45\pm 0.53$ | $0.9$ | $20$ | $\bigstar~{}~{}~{}~{}$
2M J2126-81 B | $217.49441\pm 0.00082\,\,\,\,\,\,$ | $123.98914\pm 0.00024$ | $0.04\pm 0.92$ | $0.0~{}(0.0)$ | $8.34\pm 2.34$ | $3.6$ | $30$ |
TOI 132 B | $19.64887\pm 0.00018\,\,\,$ | $151.44437\pm 0.00044$ | $0.11\pm 0.23$ | $0.5~{}(0.1)$ | $0.58\pm 0.36$ | $1.6$ | $218$ | $\bigstar~{}~{}~{}~{}$
NGTS-7 B | $1.13095\pm 0.00014$ | $117.57142\pm 0.01072$ | $0.73\pm 0.14$ | $5.1~{}(1.1)$ | $2.16\pm 0.30$ | $7.3$ | $30$ | $\bigstar^{17}$
DS Tuc B | $5.36461\pm 0.00003$ | $347.65815\pm 0.00047$ | $0.02\pm 0.05$ | $0.3~{}(0.3)$ | $2.22\pm 0.08$ | $29$ | $93$ |
1RXS J2351+3127 C | $126.01641\pm 0.00005\,\,\,\,\,\,$ | $\,\,\,98.50769\pm 0.00002$ | $0.04\pm 0.08$ | $0.5~{}(0.1)$ | $0.83\pm 0.09$ | $8.7$ | $333$ |

Comments on individual companions:

  * 1:

This companion was first reported by Vanderburg et al. (2019), who have
already verified its equidistance and common proper motion with the exoplanet
host star HR 858 A using Gaia DR2 data, consistent with the results, obtained
in this study.

  * 2:

This companion was detected by Feinstein et al. (2019) and its companionship
with the exoplanet host star K2-288 B was proven with Gaia DR2 astrometry,
confirmed by the astrometric analysis, carried out in the study, presented
here.

  * 3:

This star was already noticed in the Gaia DR2 by McCormac et al. (2020) as
common proper motion companion of the exoplanet host star NGTS-10 A,
consistent with the results, derived in this study.

  * 4:

This companion of the exoplanet host star HD 85628 A was discovered by Dorval
et al. (2020) in the Gaia DR2, who found its parallax and proper motion
consistent with that of the exoplanet host star, confirmed by the astrometric
analysis, presented here.

  * 5:

This companion was detected with AO imaging by Rodriguez et al. (2019) using
Keck/NIRC 2, but is also listed in the Gaia DR2, whose astrometry was used by
this team to verify the equidistance and common proper motion of this
companion with the exoplanet host star MASCARA-3 A, as done in this study.

  * 6:

This companion was already reported by Nielsen et al. (2019), who proved its
companionship with the exoplanet host star WASP-175 A with Gaia DR2
astrometry, consistent with the results derived here.

  * 7:

The equidistance and common proper motion of this substellar object with the
exoplanet host star 2M J1155-7919 A was verified by Dickson-Vandervelde et al.
(2020) using Gaia DR2 data, as done in this work.

  * 8:

This companion was detected by Burgasser et al. (2017) and its common proper
motion with the brown dwarf 2M J1450-7841 A, listed in the EPE, was verified
with ground based astrometry, confirmed in this study with Gaia DR2 data,
which furthermore proves the equidistance of both objects.

  * 9:

This companion was noticed by Triaud et al. (2020) in the Gaia DR2 as
equidistant and co-moving companion of the brown dwarf 2M 1510 A, which is
listed in the EPE, consistent with our results.

  * 10:

KELT-23 B was first discovered by (Johns et al., 2019) with Keck/NIRC 2 AO
imaging, who used Gaia DR2 astrometry to prove the equidistance and common
proper motion of the companion with the exoplanet host star KELT-23 A, as done
in this study.

  * 11:

This companion was already described by Hjorth et al. (2019), who have
verified it to be equidistant and co-moving with the exoplanet host star
K2-290 A, using Gaia DR2 data, a conclusion, which is confirmed by the
analysis, presented here. Furthermore, this team identified an additional but
closer stellar companion-candidate of the exoplanet host star (K2-290 B) with
Subrau/IRCS AO imaging, which however still needs astrometric confirmation of
its companionship. Due to its close angular separation to K2-290 A we adopt
here this object as companion of the exoplanet host star.

  * 12:

This companion was revealed spectro-photometrically by Aller et al. (2013).
With Gaia DR2 astrometry we prove here its companionship with the exoplanet
host star HIP 77900 A.

  * 13:

HIP 79098 C was reported by (Janson et al., 2019) as equidistant and co-moving
companion of the exoplanet host star HIP 79098 A, based on its Gaia DR2
astrometry, confirmed by the analysis of the companion, which is presented
here.

  * 14:

This companion was revealed spectro-photometrically by Aller et al. (2013).
The equidistance and common proper motion of this companion with the exoplanet
host star USco 1612-1800 A was proven in this study, with Gaia DR2 astrometry.

  * 15:

This star was identified by (Bowler et al., 2017) as companion of ROXs 12 A,
based on its radial velocity and proper motion. We prove the equidistance of
both stars with their Gaia DR2 astrometry, which also confirms their common
proper motion.

  * 16:

This companion was reported by (Hartman et al., 2020), who used the Gaia DR2
astrometry to confirm its companionship with the exoplanet host star HATS-48
A, as done in this work.

  * 17:

NGTS-7 B was revealed by (Jackman et al., 2019) as companion of the exoplanet
host star NGTS-7 A using Gaia DR2 astrometry, as done in this study.

Table 4: The equatorial coordinates and derived physical properties of all detected companions. Companion | $\alpha$ | $\delta$ | $M_{G}$ | $sep$ | $mass$ | $T_{eff}$ | Flags
---|---|---|---|---|---|---|---
| [∘] | [∘] | [mag] | [au] | [$M_{\odot}$] | [K] |
HD 1160 C | $\,\,\,\,\,\,3.98858470355$ | $\,\,\,\,\,\,4.25245524714$ | $\,\,9.72_{-0.13}^{+0.10}$ | $648$ | $0.378_{-0.016}^{+0.021}$ | $3503_{-19}^{+25}$ | BPRP PRI
Gliese 49 B | $\,\,\,15.83942593995$ | $\,\,\,\,62.36588062663$ | $11.35_{-0.22}^{+0.41}$ | $2902$ | $0.169_{-0.030}^{+0.020}$ | $3211_{-74}^{+40}$ | 2MA BPRP PRI
HD 8326 B | $\,\,\,20.54104760211$ | $-26.90734439784$ | $11.48_{-0.25}^{+0.04}$ | $1747$ | $0.198_{-0.003}^{+0.023}$ | $3257_{-7}^{+37}$ | 2MA BPRP PRI
HD 13167 B | $\,\,\,32.06020575541$ | $-24.69051459458$ | $11.33_{-0.06}^{+0.07}$ | $3001$ | $0.211_{-0.007}^{+0.006}$ | $3279_{-10}^{+9}$ | 2MA BPRP
HR 858 B | $\,\,\,42.98571355919$ | $-30.81182706733$ | $13.39_{-0.11}^{+0.09}$ | $267$ | $0.112_{-0.002}^{+0.003}$ | $2926_{-19}^{+20}$ | BPRP PRI
HD 18015 B | $\,\,\,43.36225373946$ | $\,\,\,-8.84661863284$ | $\,\,6.62_{-0.04}^{+0.04}$ | $881$ | $0.747_{-0.004}^{+0.004}$ | $4650_{-18}^{+20}$ | 2MA BPRP PRI
K2-288 A | $\,\,\,55.44420842474$ | $\,\,\,\,18.26869720107$ | $\,\,8.65_{-0.09}^{+0.09}$ | $52$ | $0.534_{-0.010}^{+0.010}$ | $3777_{-28}^{+30}$ | 2MA
HD 23472 B | $\,\,\,55.46315889099$ | $-62.76539647729$ | $12.79_{-0.18}^{+0.07}$ | $374$ | $0.129_{-0.002}^{+0.006}$ | $3038_{-13}^{+30}$ | 2MA BPRP PRI
HD 24085 A | $\,\,\,56.19506729271$ | $-70.02706843481$ | $\,\,2.90_{-0.59}^{+0.39}$ | $4174$ | $1.254_{-0.058}^{+0.088}$ | $\,\,6339_{-139}^{+211}$ | 2MA BPRP PRI EXT
HII 1348 C | $\,\,\,56.81444339267$ | $\,\,\,\,24.39176993016$ | $10.07_{-0.31}^{+0.33}$ | $5155$ | $0.322_{-0.046}^{+0.048}$ | $3436_{-60}^{+58}$ | 2MA BPRP PRI ***
HII 1348 D | $\,\,\,56.82474725542$ | $\,\,\,\,24.37529892928$ | $14.35_{-0.37}^{+0.46}$ | $7872$ | $0.055_{-0.006}^{+0.005}$ | $2602_{-96}^{+78}$ | BD 2MA BPRP ***
HATS-57 B | $\,\,\,60.94413061754$ | $-19.05596683949$ | $10.25_{-0.18}^{+0.05}$ | $4068$ | $0.331_{-0.007}^{+0.023}$ | $3448_{-7}^{+24}$ | 2MA BPRP
FU Tau B | $\,\,\,65.89894960541$ | $\,\,\,\,25.04979704793$ | $12.62_{-0.26}^{+0.49}$ | $749$ | $0.018_{-0.003}^{+0.002}$ | $2553_{-71}^{+38}$ | BD 2MA BPRP
DH Tau C | $\,\,\,67.42700661202$ | $\,\,\,\,26.54688636442$ | $\,\,3.64_{-0.37}^{+0.17}$ | $2071$ | $1.655_{-0.106}^{+0.228}$ | $\,\,4837_{-77}^{+164}$ | 2MA BPRP PRI EXT
51 Eri B (SB) | $\,\,\,69.40630139702$ | $\,\,\,-2.49157819607$ | $\,\,7.18_{-0.27}^{+0.11}$ | $1994$ | $0.733_{-0.024}^{+0.056}$ | $\,\,3962_{-49}^{+116}$ | 2MA BPRP PRI ***
2M 0441+23 AB1 | $\,\,\,70.44024465438$ | $\,\,\,\,23.03268965375$ | $\,\,7.37_{-0.96}^{+0.43}$ | $1483$ | $0.241_{-0.061}^{+0.147}$ | $\,\,3308_{-138}^{+300}$ | 2MA BPRP
NGTS-6 B | $\,\,\,75.79692465277$ | $-30.40013000839$ | $\,\,9.23_{-0.10}^{+0.14}$ | $1667$ | $0.457_{-0.018}^{+0.013}$ | $3618_{-29}^{+21}$ | 2MA BPRP PRI
AB Dor BD | $\,\,\,82.18603484814$ | $-65.44557858318$ | $\,\,9.08_{-0.52}^{+0.44}$ | $136$ | $0.466_{-0.059}^{+0.061}$ | $\,\,3645_{-104}^{+167}$ | 2MA BPRP PRI ***
HD 39855 B | $\,\,\,88.62713212305$ | $-19.70163948841$ | $\,\,8.02_{-0.23}^{+0.13}$ | $250$ | $0.598_{-0.014}^{+0.024}$ | $\,\,3978_{-41}^{+103}$ | 2MA BPRP PRI
NGTS-10 B | $\,\,\,91.87213254706$ | $-25.59461438962$ | $\,\,7.27_{-1.21}^{+0.61}$ | $364$ | $0.665_{-0.059}^{+0.121}$ | $\,\,4327_{-284}^{+606}$ |
L2 Pup B | $108.39678197580$ | $-44.63427669967$ | $11.39_{-0.33}^{+0.17}$ | $2101$ | $0.203_{-0.012}^{+0.032}$ | $3270_{-26}^{+49}$ |
HIP 38594 B | $118.48449010900$ | $-25.39952189079$ | $14.43_{-0.78}^{+0.26}$ | $7116$ | $\sim 0.6$ |  | WD 2MA BPRP PRI
WASP-180 B | $123.39313443835$ | $\,\,\,-1.98380547425$ | $\,\,4.64_{-0.16}^{+0.06}$ | $1244$ | $1.057_{-0.011}^{+0.029}$ | $5778_{-36}^{+93}$ | 2MA BPRP PRI
HD 79211 A | $138.58391575741$ | $\,\,\,\,52.68415915741$ | $\,\,7.59_{-0.33}^{+0.21}$ | $108$ | $0.644_{-0.022}^{+0.034}$ | $\,\,4180_{-97}^{+153}$ | 2MA BPRP PRI
Table 4: continued Companion | $\alpha$ | $\delta$ | $M_{G}$ | $sep$ | $mass$ | $T_{eff}$ | Flags
---|---|---|---|---|---|---|---
| [∘] | [∘] | [mag] | [au] | [$M_{\odot}$] | [K] |
HD 85628 B | $147.57796550484$ | $-66.11477795490$ | $\,\,7.38_{-0.15}^{+0.23}$ | $744$ | $0.675_{-0.025}^{+0.016}$ | $\,\,4282_{-104}^{+66}$ | BPRP PRI
TOI 717 B | $147.98872815946$ | $\,\,\,\,\,\,\,2.11708155887$ | $\,\,9.72_{-0.13}^{+0.02}$ | $2275$ | $0.398_{-0.003}^{+0.017}$ | $3519_{-3}^{+25}$ | 2MA BPRP PRI
G 196-3 B | $151.08506490419$ | $\,\,\,\,50.38228242112$ | $17.41_{-0.49}^{+0.48}$ | $350$ | $0.032_{-0.002}^{+0.002}$ | $1987_{-93}^{+94}$ | BD 2MA BPRP
LTT 3780 B | $154.64934761666$ | $-11.71834621199$ | $12.27_{-0.26}^{+0.34}$ | $347$ | $0.149_{-0.014}^{+0.014}$ | $3127_{-58}^{+43}$ | 2MA BPR PPRI
MASCARA-3 B | $161.90924448675$ | $\,\,\,\,71.65515762432$ | $\,\,7.83_{-0.28}^{+0.12}$ | $200$ | $0.625_{-0.013}^{+0.030}$ | $\,\,4074_{-53}^{+126}$ |
2M J1101-7732 B | $165.33045751133$ | $-77.54374799758$ | $12.48_{-0.14}^{+0.14}$ | $264$ | $0.019_{-0.001}^{+0.001}$ | $2574_{-21}^{+21}$ | BD
WASP-175 B | $166.31900970217$ | $-34.12073886500$ | $\,\,5.46_{-0.11}^{+0.10}$ | $3971$ | $0.919_{-0.016}^{+0.018}$ | $5290_{-60}^{+65}$ | 2MA BPR PPRI
CHXR 73 C | $166.56385863699$ | $-77.63060598303$ | $\,\,8.04_{-1.03}^{+1.03}$ | $8808$ | $0.235_{-0.112}^{+0.148}$ | $\,\,3280_{-260}^{+295}$ | 2MA BPRP
GJ 414 B | $167.76359381364$ | $\,\,\,\,30.44392150823$ | $\,\,8.06_{-0.57}^{+0.32}$ | $406$ | $0.587_{-0.034}^{+0.056}$ | $\,\,3971_{-110}^{+249}$ | 2MABPRP PRI
HD 97334 BC2 | $168.10555672848$ | $\,\,\,\,35.80289455668$ | $18.16_{-0.19}^{+0.04}$ | $2036$ | $0.028_{-0.001}^{+0.001}$ | $1845_{-8}^{+36}$ | BD 2MA BPRP
HD 233832 B | $171.51750545565$ | $\,\,\,\,50.37622350226$ | $\,\,8.64_{-0.21}^{+0.11}$ | $290$ | $0.531_{-0.012}^{+0.022}$ | $3775_{-36}^{+68}$ | 2MA BPRP PRI
2M J1155-7919 B | $178.76276748600$ | $-79.32082818366$ | $14.48_{-0.06}^{+0.02}$ | $582$ | $0.016_{-0.001}^{+0.001}$ | $2366_{-2}^{+10}$ | BD 2MA BPRP
NGTS-5 B | $221.06499706987$ | $\,\,\,\,\,\,\,5.60206193982$ | $\,\,9.67_{-0.11}^{+0.12}$ | $8323$ | $0.405_{-0.016}^{+0.014}$ | $3530_{-20}^{+22}$ | 2MA BPRP
2M J1450-7841 B | $222.67064914833$ | $-78.69407266366$ | $15.35_{-0.51}^{+0.51}$ | $387$ | $0.031_{-0.003}^{+0.005}$ | $\,\,2328_{-100}^{+114}$ | BD 2MA BPRP
WASP-189 B | $225.68920534342$ | $\,\,\,-3.03062676806$ | $\,\,9.12_{-0.16}^{+0.23}$ | $942$ | $0.479_{-0.030}^{+0.021}$ | $3646_{-48}^{+33}$ | 2MA BPRP PRI
HIP 73990 D | $226.82470360183$ | $-29.49738818566$ | $\,\,8.33_{-0.64}^{+0.45}$ | $5234$ | $0.470_{-0.098}^{+0.151}$ | $\,\,3576_{-107}^{+191}$ | 2MA BPRP PRI
TOI 905 B | $227.66059753260$ | $-71.36174373792$ | $10.93_{-0.14}^{+0.17}$ | $358$ | $0.251_{-0.016}^{+0.014}$ | $3340_{-25}^{+21}$ |
2M 1510 B | $227.69777941730$ | $-28.30671294175$ | $15.13_{-0.14}^{+0.03}$ | $249$ | $0.033_{-0.001}^{+0.001}$ | $2376_{-6}^{+31}$ | BD 2MA BPRP
$\beta$ Cir B | $229.33920903332$ | $-58.85886078926$ | $16.91_{-0.23}^{+0.16}$ | $6187$ | $0.063_{-0.002}^{+0.002}$ | $2159_{-48}^{+47}$ | BD 2MA BPRP
KELT-23 B | $232.14912993468$ | $\,\,\,\,66.35793842725$ | $\,\,9.94_{-0.10}^{+0.05}$ | $575$ | $0.368_{-0.007}^{+0.014}$ | $3487_{-7}^{+15}$ | 2MA BPRP PRI
K2-290 C | $234.85788601749$ | $-20.20202286624$ | $10.51_{-0.26}^{+0.27}$ | $3094$ | $0.292_{-0.026}^{+0.033}$ | $3404_{-41}^{+38}$ | 2MA BPRP***
GQ Lup C | $237.30537201266$ | $-35.65336961027$ | $\,\,9.70_{-0.34}^{+0.42}$ | $2446$ | $0.075_{-0.015}^{+0.016}$ | $2897_{-33}^{+14}$ | 2MA BPRP
HIP 77900 B | $238.62692763313$ | $-27.33270712891$ | $13.48_{-0.16}^{+0.05}$ | $3374$ | $0.020_{-0.001}^{+0.001}$ | $2519_{-8}^{+22}$ | BD BPRP
USco 1602-2401 B3 | $240.71312906858$ | $-24.03074240242$ | $\,\,8.69_{-0.12}^{+0.12}$ | $1038$ | $0.238_{-0.017}^{+0.016}$ | $3280_{-27}^{+25}$ | 2MA BPRP PRI
Table 4: continued

Companion | $\alpha$ | $\delta$ | $M_{G}$ | $sep$ | $mass$ | $T_{eff}$ | Flags
---|---|---|---|---|---|---|---
| [∘] | [∘] | [mag] | [au] | [$M_{\odot}$] | [K] |
HIP 79098 C | $242.20150369275$ | $-23.68925441843$ | $\,\,9.82_{-0.15}^{+0.24}$ | $9555$ | $0.159_{-0.020}^{+0.013}$ | $3176_{-40}^{+24}$ | 2MA BPRP PRI ***
USco 1610-1913 B | $242.63466253957$ | $-19.21910506083$ | $12.71_{-0.39}^{+0.39}$ | $777$ | $0.025_{-0.003}^{+0.003}$ | $2615_{-47}^{+47}$ | BD 2MA BPRP
USco 1612-1800 B | $243.20402838620$ | $-18.01380384763$ | $12.50_{-0.39}^{+0.39}$ | $504$ | $0.026_{-0.003}^{+0.003}$ | $2642_{-48}^{+48}$ | BD BPRP
ROXs 12 C | $246.61560598363$ | $-25.45695531769$ | $\,\,7.28_{-1.00}^{+1.00}$ | $5095$ | $0.474_{-0.181}^{+0.259}$ | $\,\,3657_{-289}^{+343}$ | 2MA BPR PPRI
HATS-48 B | $288.66902407326$ | $-59.57941400923$ | $11.71_{-0.19}^{+0.37}$ | $1444$ | $0.181_{-0.022}^{+0.013}$ | $3219_{-60}^{+30}$ | 2MA BPRP
GJ 752 B | $289.23745710752$ | $5.14456304678$ | $14.04_{-0.28}^{+0.17}$ | $446$ | $0.098_{-0.002}^{+0.005}$ | $2785_{-36}^{+60}$ | 2MA BPRP PRI
HD 181234 B | $290.00108472870$ | $-9.32417966740$ | $10.46_{-0.20}^{+0.07}$ | $247$ | $0.297_{-0.007}^{+0.026}$ | $3412_{-11}^{+29}$ | 2MA BPRP PRI
Wendelstein-1 B | $299.04791069915$ | $17.56797448132$ | $11.43_{-0.47}^{+0.43}$ | $3632$ | $0.202_{-0.030}^{+0.047}$ | $3264_{-70}^{+72}$ | 2MA BPRP
2M J2126-81 B | $321.71158783493$ | $-81.67526360458$ | $17.84_{-0.43}^{+0.05}$ | $7427$ | $0.020_{-0.004}^{+0.001}$ | $1851_{-77}^{+41}$ | BD 2MA BPRP
TOI 132 B | $338.40325545731$ | $-43.44166603901$ | $12.21_{-0.16}^{+0.14}$ | $3231$ | $0.152_{-0.006}^{+0.009}$ | $3137_{-24}^{+27}$ | 2MA BPRP
NGTS-7 B | $352.52202473338$ | $-38.97006605140$ | $\,\,9.32_{-0.50}^{+0.50}$ | $156$ | $0.384_{-0.091}^{+0.097}$ | $\,\,3495_{-97}^{+102}$ |
DS Tuc B | $354.91457052896$ | $-69.19458723114$ | $\,\,5.86_{-0.24}^{+0.10}$ | $237$ | $0.834_{-0.027}^{+0.060}$ | $\,\,5040_{-79}^{+180}$ | 2MA BPRP PRI
1RXS J2351+3127 C | $357.93142859121$ | $31.45083817280$ | $\,\,9.61_{-0.43}^{+0.04}$ | $5427$ | $0.394_{-0.007}^{+0.057}$ | $3522_{-8}^{+98}$ | 2MA BPRP PRI

Table Footnotes:

1: 2M 0441+23 B is a close brown dwarf companion of 2M 0441+23 A.

2: HD 97334 BC is a binary brown dwarf system.

3: The brown dwarf USco 1602-2401 B was detected by Aller et al. (2013) and
its possible companionship to USco 1602-2401 A, was revealed with photometry
and follow-up spectroscopy, which was finally proven in this study with the
Gaia DR2 astrometry of the companion, i.e. confirmation of equidistance, and
common proper motion, as well as test for gravitational stability. USco
1602-2401 B is one of 14 reported substellar companions, detected by Gaia,
which were also characterized in this study using their Gaia DR2 astro- and
photometry. In general, the derived mass of these substellar companions agrees
well with the mass given in the literature, with a deviation of only a few
$M_{Jup}$, on average. In contrast, for USco 1602-2401 B Aller et al. (2013)
derived a mass of $41^{+20}_{-13}\,M_{Jup}$ at an age of 5 Myr
($47^{+20}_{-18}\,M_{Jup}$ at 10 Myr) adopting a distance of about 145 pc and
no extinction. With the Gaia DR2 parallax and the Starhorse extinction
estimate of the primary star and the G-band photometry of the companion we
obtained a significantly higher mass of $0.238^{+0.016}_{-0.017}\,M_{\odot}$
at 5 Myr ($0.309^{+0.020}_{-0.019}\,M_{\odot}$ at 10 Myr). Adopting $A_{G}=0$
mag yields a mass of the companion of $0.071^{+0.001}_{-0.001}\,M_{\odot}$ for
5 Myr, and $0.104^{+0.001}_{-0.001}\,M_{\odot}$ for 10 Myr, respectively.
Therefore, we classify this companion here as low-mass star.

Table 5: List of all detected companions, whose differential proper motion $\mu_{rel}$ exceeds their estimated escape velocity $\mu_{esc}$. Companion | $\mu_{rel}$ | $\mu_{esc}$ |
---|---|---|---
|  $[$mas/yr$]$ |  $[$mas/yr$]$ |
51 Eri B (SB) | $19.04\pm 0.71$ | $11.298\pm 0.144$ | ***
HIP 38594 B | $\,\,\,6.44\pm 0.24$ | $\,\,\,4.965\pm 0.082$ |
TOI 905 B | $\,\,\,7.67\pm 0.76$ | $\,\,\,3.090\pm 0.144$ |

##  7 Figures

Figure 1: The histograms of the individual properties of all targets of this
study.

Figure 2: Comparison of the mass of the detected companions, derived from
their G-band and infrared 2MASS photometry.

Figure 3: The cumulative distribution function of the projected separation
($sep$) of all detected companions to the associated exoplanet hosts.

Figure 4: The cumulative distribution function of the mass of all companions,
detected in this study.

Figure 5: The cumulative distribution function of the effective temperature of
all detected companions.

Figure 6: The mass of all companions, detected in this study, plotted over
their projected separation ($sep$) to the associated exoplanet hosts. The
white dwarf companion HIP 38594 B, is illustrated as open circle.

Figure 7: The G-band magnitude difference of all detected companions, plotted
over their angular separation to the associated exoplanet hosts.