2022 106 23 May

$\rm\Omega_{c}^{0}$ production in pp collisions at $\sqrt{s}=13$ TeV

ALICE Collaboration††thanks: See Appendix A for the list of collaboration
members ALICE Collaboration

The inclusive production of the charm–strange baryon $\Omega_{\rm c}^{0}$ is
measured for the first time via its hadronic decay into $\rm\Omega^{-}\pi^{+}$
at midrapidity ($|y|<0.5$) in proton–proton (pp) collisions at the centre-of-
mass energy $\sqrt{s}=13$ TeV with the ALICE detector at the LHC. The
transverse momentum ($p_{\rm T}$) differential cross section multiplied by the
branching ratio is presented in the interval $2<p_{\rm T}<12~{}{\rm GeV}/c$.
The $p_{\rm T}$ dependence of the $\rm\Omega_{c}^{0}$-baryon production
relative to the prompt $\rm D^{0}$-meson and to the prompt
$\rm\Xi_{c}^{0}$-baryon production is compared to various models that take
different hadronisation mechanisms into consideration. In the measured $p_{\rm
T}$ interval, the ratio of the $p_{\rm T}$-integrated cross sections of
$\rm\Omega_{c}^{0}$ and prompt $\Lambda_{\rm c}^{+}$ baryons multiplied by the
$\rm\Omega^{-}\pi^{+}$ branching ratio is found to be larger by a factor of
about 20 with a significance of about 4$\sigma$ when compared to $\rm
e^{+}e^{-}$ collisions.

Recent measurements of charm-baryon production at midrapidity by the ALICE
Collaboration [1, 2, 3, 4, 5] show that the $\Lambda_{\rm c}^{+}/\rm D^{0}$,
$\Xi_{\rm c}^{0,+}/\rm D^{0}$, and $\Sigma_{\rm c}^{0,++}/\rm D^{0}$ baryon-
to-meson yield ratios are higher in pp collisions at LHC energies than in $\rm
e^{+}e^{-}$ collisions, indicating that charm hadronisation occurs via
different processes in the two collision systems [6]. The ratios are found to
decrease with increasing transverse momentum ($p_{\rm T}$), a trend not
expected by models based on factorisation and on the usage of the
fragmentation functions extracted from $\rm e^{+}e^{-}$ collisions. A
significant dependence of the $p_{\rm T}$-differential $\Lambda_{\rm
c}^{+}/\rm D^{0}$ ratio with the multiplicity of charged particles produced in
the event was also observed in pp collisions at $\sqrt{s}=13$ TeV [7],
possibly suggesting a continuous evolution of this ratio from low-multiplicity
pp collisions to the highest multiplicity of charged particles characterising
Pb–Pb collisions with a small impact parameter [8].

Higher charm baryon-to-meson ratios in pp collisions with respect to $\rm
e^{+}e^{-}$ collisions are expected by models that either include dynamical
processes that are relevant in quark-and-gluon enriched systems (e.g. colour
reconnection beyond leading colour approximation [9] and quark coalescence
[10]), or that treat hadronisation as a statistical process [11, 12].

The Lund string fragmentation model [13, 14] implemented in the PYTHIA event
generator [15, 16, 17], is one of the main hadronisation models used in
general-purpose Monte Carlo event generators [18]. In the default version of
PYTHIA 8 (Monash 2013 tune [19]), the choice of quarks and gluons that are
matched to form strings, encoding colour-confining potentials, is done in the
leading-colour approximation. This configuration suppresses the connection of
quarks and gluons coming from independent parton scatterings, realising heavy-
quark fragmentation and hadronisation schemes very similar to those occurring
in $\rm e^{+}e^{-}$ collisions. As a result, all of the baryon-to-meson ratios
mentioned above are severely underestimated. The extension of colour
reconnection beyond the leading colour (CR-BLC) approximation [9] allows the
calculations to better approximate quantum chromodynamic colour algebra when
matching partons to form strings and enhances the role of “junction" colour-
topologies that favour the formation of baryons. The CR-BLC model reproduces
the $\Lambda_{\rm c}^{+}/\rm D^{0}$ ratio, including the dependence on event
multiplicity [7], and the $\Sigma_{\rm c}^{0,++}/\rm D^{0}$ ratio [3], but it
underestimates the $\Xi_{\rm c}^{0,+}/\rm D^{0}$ [4, 5].

In the Catania model [10], charm quarks can hadronise via “vacuum"-like
fragmentation as well as recombine (coalesce) with surrounding light quarks
from the underlying event. The Wigner formalism is used to calculate the
probability to form a baryon (meson) given the phase-space distribution of
three (two) quarks. Within uncertainties, this model reproduces the charm
baryon-to-meson ratios measured so far in pp collisions, though it tends to
systematically underpredict the $\Xi_{\rm c}^{0,+}/\rm D^{0}$ and the
$\Xi_{\rm c}^{0,+}/\Sigma_{\rm c}^{0,++}$ ratios.

In the models implementing hadronisation on a statistical basis, the relative
abundances of the various charm-hadron species are determined by statistical
weights that depend on the hadron mass, spin, and on the system properties.
The $p_{\rm T}$ dependence of the predicted ratios can have different origins.
It derives from the feed-down from higher-mass state decays in the model of
Ref. [12], in which a large set of not-yet-observed charm-baryon states is
assumed, following the expectation of the relativistic quark model [20]. In
the quark-recombination model (QCM) [11] it instead derives from the
requirement that charm quarks form hadrons by combining with light quarks with
the same velocity. Both models describe the $\Lambda_{\rm c}^{+}/\rm D^{0}$
and $\Sigma_{\rm c}^{0,++}/\rm D^{0}$ ratios and underestimate the $\Xi_{\rm
c}^{0,+}/\rm D^{0}$ ratio in pp collisions, with the QCM prediction being
closer to the data, although lower by about a factor of two.

The $\Omega_{\rm c}^{0}$ baryon is composed of a charm quark and two strange
quarks. The mentioned models can reproduce $\Lambda_{\rm c}^{+}$ data better
than $\Xi_{\rm c}^{0,+}$ data. This signals a possible difficulty with charm-
strange baryons and suggests that the measurement of $\Omega_{\rm c}^{0}$
production represents a crucial step to constrain models and understand
whether strange quarks, or strange diquarks, play a peculiar role in charm-
baryon formation in pp collisions. In high-energy nucleus–nucleus collisions,
the production yields of strange hadrons, in particular of multiple-strange
baryons, normalised to pion ones are enhanced with respect to pp collisions
and are well described by statistical models using a grand canonical ensemble
with strangeness production regulated by chemical equilibrium [21, 22, 23, 24,
25, 26, 27]. Measurements of $\Omega^{-}$ and $\Xi^{-}$ production as a
function of the event multiplicity suggest that the onset of such enhancement
occurs progressively with increasing particle multiplicity, starting from low-
multiplicity pp collisions [25]. In this context, it is however interesting to
note that although current data do not exclude that the $\rm D^{+}_{s}/\rm
D^{0}$ ratio in pp collisions could be larger than in $\rm e^{+}e^{-}$
collisions, they do not support an increase similar, in relative terms, to
that of $\Xi_{\rm c}^{0,+}/\rm D^{0}$ ratio. Indeed, the analysis of charm
fragmentation fractions reported in Ref. [6] suggests that the sum of the
${\rm c}\rightarrow\Xi_{\rm c}^{0}$ and ${\rm c}\rightarrow\Xi_{\rm c}^{+}$
fragmentation fractions could be larger than the ${\rm c}\rightarrow\rm
D^{+}_{s}$ one. Another interesting observation is given by the fact that the
$\Xi_{\rm c}^{0,+}/\Sigma_{\rm c}^{0,++}$ ratio is described well by the
default PYTHIA 8 Monash tune [5], which significantly underestimates both
$\Xi_{\rm c}^{0,+}/\rm D^{0}$ and $\Sigma_{\rm c}^{0,++}/\rm D^{0}$ ratios,
suggesting that the production of the two baryons could be equally suppressed
in $\rm e^{+}e^{-}$ collisions because of similar mechanisms. The fraction of
$\Lambda_{\rm c}^{+}$ coming from $\Sigma_{\rm c}^{0,++}$ decays is larger by
a factor of about two in pp collisions than in $\rm e^{+}e^{-}$ collisions
[3]: this supports the interpretation [9, 28]that in $\rm e^{+}e^{-}$
collisions the $\Sigma_{\rm c}^{0,++}$ formation is suppressed by the need of
forming in string breaking a (dd, ud, uu)-diquark with spin $S=1$, which is
heavier than the $S=0$ (ud)-diquark needed to form a $\Lambda_{\rm c}^{+}$. A
similar argument might be relevant in the comparison of $\Omega_{\rm c}^{0}$
and $\Xi_{\rm c}^{0,+}$ production, possibly influenced by the different mass
values of $S=1$ (ss) and $S=0$ (sd, su) diquarks [20]. This further highlights
the importance of measuring the $\Omega_{\rm c}^{0}$ production cross section
to understand the role played by strange quarks and diquarks in charm-quark
hadronisation. The measurement of the production cross section of the
$\Omega_{\rm c}^{0}$ baryon is also needed to quantify its possible
significant contribution to the total charm cross section at midrapidity per
unit of rapidity, both in pp and in Pb–Pb collisions at the LHC [6].

This Letter reports on the first measurement of the $p_{\rm T}$-differential
production cross section of the inclusive $\rm\Omega_{c}^{0}$ baryon
multiplied by the branching ratio (BR) of the hadronic decay channel
$\rm\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+}$ at midrapidity ($|y|<0.5$) in
pp collisions at $\sqrt{s}=13$ TeV. Inclusive $\rm\Omega_{c}^{0}$ include
prompt $\rm\Omega_{c}^{0}$, produced directly in the hadronisation of charm
quarks or in the decay of directly produced excited charm states, as well as
$\rm\Omega_{c}^{0}$ from decays of beauty or multiple-charm hadron decays. The
ratios of the inclusive $\rm\Omega_{c}^{0}$ cross section to the prompt $\rm
D^{0}$ meson [3] and to the prompt charm–strange $\rm\Xi_{c}^{0}$ baryon [5]
are also reported. The absolute branching ratio of the decay channel used has
not been measured yet. The $\rm\Omega_{\rm c}^{0}$ baryon was reconstructed
together with its charge conjugate in the interval $2<p_{\rm T}<12$ GeV$/c$.

A description of the ALICE detector and its performance can be found in Refs.
[29, 30]. The main detectors used for this measurement are the Inner Tracking
System (ITS), the Time Projection Chamber (TPC), and the Time-Of-Flight
detector (TOF). They are located in the central barrel, which covers the
pseudorapidity interval ($|\eta|<0.9$), and are embedded in a solenoidal
magnet that provides a $\rm B=0.5$ T field parallel to the beam direction. The
ITS is used for tracking, vertex reconstruction, and trigger purposes. The TPC
is the main tracking detector in the central barrel and is also used for
particle identification (PID) via the measurement of the particle specific
energy loss (${\rm d}E/{\rm d}x$). The TOF provides PID information via the
measurement of the particle time-of-flight relative to the time of the
collision [31]. The analysed data sample consists of pp collisions at
$\sqrt{s}=13$ TeV recorded with a minimum-bias (MB) trigger based on
coincident signals in the two scintillator arrays (V0) located on both sides
of the nominal interaction point along the beam direction. Offline selection
criteria, based on the signals from the V0 and the Silicon Pixel Detector,
which constitutes the two innermost ITS layers, were applied to remove
background due to the interaction between one of the beams and the residual
gas present in the beam vacuum tube as well as other machine-induced
backgrounds [32]. Events with multiple reconstructed primary vertices, which
amount to 1% of the total event sample, were rejected to reduce the
contamination from the superposition of several collisions within the same
colliding bunches (pile-up events). Only events with a primary vertex position
within 10 cm from the nominal interaction point along the beam direction were
used. After the aforementioned selections, the data sample corresponds to an
integrated luminosity $\mathcal{L}_{\rm int}=$ 32.08 $\pm$ 0.51 ${\rm
nb^{-1}}$ [33].

The $\rm\Omega_{c}^{0}$-baryon candidates were built from
$\rm\Omega^{-}\pi^{+}$ pairs using a Kalman-Filter (KF) vertexing algorithm
[34] by combining a positive charged track ($\rm\pi^{+}$ candidate)
originating from the primary vertex and a $\rm\Omega^{-}$-baryon candidate.
The $\rm\Omega^{-}$ was reconstructed from the decay chain
$\rm\Omega^{-}\rightarrow\Lambda K^{-}$, ${{\rm BR}=(67.8\pm 0.7)}$%, followed
by $\rm\Lambda\rightarrow p\pi^{-}$, BR $=$ ($63.9\pm 0.5$)% [35]. The
$\rm\Omega^{-}$ and $\rm\Lambda$ baryons were reconstructed by exploiting
their characteristic decay topologies as reported in Refs. [5, 36]. The tracks
of the charged particles involved in the decay chain were required to be in
the pseudorapidity interval $|\eta|<0.8$, to have at least 70 out of 159
crossed TPC tracking points, and to have a fit quality $\chi^{2}/{\rm NDF}<2$
in the TPC. Moreover, primary $\rm\pi^{+}$ candidates were required to have a
minimum of four (out of six) hits in the ITS. Protons, pions, and kaons were
selected by requiring compatibility within four standard deviations
($4\sigma$) between the measured signal and that expected for the respective
particle hypothesis for both the TPC ${\rm d}E/{\rm d}x$ and the time-of-
flight measurement. Tracks without signal in the TOF detector were identified
using only the TPC information. In order to reduce the large combinatorial
background, a machine-learning approach based on the adaptive Boosted Decision
Tree (BDT) algorithm in the Toolkit for Multivariate Data Analysis (TMVA) [37]
was used. The signal sample of $\rm\Omega_{c}^{0}$ baryons for the BDT
training was obtained from a simulation based on the PYTHIA 8.243 event
generator [17]. The mean proper lifetime of $\rm\Omega_{c}^{0}$ in the
simulation was set to 80 $\rm\mu m$ according to the latest LHCb measurement
[38]. The propagation of the generated particles through the detector was
performed using the GEANT 3 package [39]. The luminous region distribution and
the conditions of all ALICE detectors in terms of active channels, gain, noise
level, and alignment, and their evolution with time during the data taking,
were taken into account in the simulations. The background candidates were
taken from data by selecting candidates with invariant mass in the intervals
$2.39<M<2.62$ GeV$/c^{2}$ and $2.77<M<2.99$ GeV$/c^{2}$, which are outside of
the expected mass peak of the $\rm\Omega_{c}^{0}$. Before the training, loose
selections were applied on the distance, normalised to its uncertainty,
between the $\rm\Lambda$ decay point and the primary vertex, and on the
$\rm\Lambda$, $\rm\Omega^{-}$, and $\rm\Omega_{c}^{0}$ $\chi^{2}_{\rm geo}/\rm
NDF$, which is a variable calculated by the KF Particle algorithm [34] related
to the intersection probability of the daughter-particle trajectories taking
their uncertainties into account. The BDT model was trained independently for
each $p_{\rm T}$ interval with variables related to the $\rm\Omega^{-}$ decay
topology, such as the distance of closest approach (DCA) of the decay
particles, the DCA between the primary vertex and the reconstructed
$\rm\Omega^{-}$ candidate, the pointing angle of the reconstructed
$\rm\Omega^{-}$ decay vertex to the reconstructed $\rm\Omega_{c}^{0}$ decay
vertex, the $\chi^{2}_{\rm geo}/\rm NDF$, and the $\chi^{2}_{\rm topo}/\rm
NDF$. The $\chi^{2}_{\rm topo}/\rm NDF$ is calculated by the KF Particle [34]
algorithm and characterises whether the $\rm\Omega^{-}$ candidate points back
to the reconstructed $\rm\Omega_{c}^{0}$ decay vertex. The output of the BDT
training allows the classification of each candidate with a number related to
its probability to be a $\rm\Omega_{c}^{0}$ baryon signal or combinatorial
background.

The $\rm\Omega_{c}^{0}$ raw yields were obtained from the fit to the
invariant-mass distribution of the candidates as shown in the left panel of
Fig. 1. The signal peak was modelled with a Gaussian function and the
background was described by a linear function.

The $p_{\rm T}$ and $y$-differential production cross section in the rapidity
interval $|y|<0.5$ of inclusive $\rm\Omega_{c}^{0}$ baryons multiplied by the
branching ratio into the considered hadronic decay channel was calculated from
the raw yields as follows

${\rm BR}\times\frac{\text{d}^{2}\sigma^{\Omega^{0}_{\rm
c}}}{\text{d}p_{\mathrm{T}}\text{d}y}=\frac{1}{2\Delta y\Delta
p_{\mathrm{T}}}\times\frac{N^{\Omega^{0}_{\rm c}+\overline{\Omega}{}^{0}_{\rm
c}}_{\text{raw}}}{({\rm Acc}\times{\it\varepsilon})_{\rm
inclusive}}\times\frac{1}{\mathcal{L}_{\rm int}},$ (1)

where $N^{\Omega^{0}_{\rm c}+\overline{\Omega}{}^{0}_{\rm c}}_{\text{raw}}$ is
the raw yield in a given $p_{\rm T}$ interval with width $\Delta p_{\rm T}$
and in the rapidity interval $\Delta y=1.6$ assuming that the cross section
does not vary significantly from $|y|<0.5$ to $|y|<0.8$. To confirm that this
assumption has a negligible impact on the result, it was verified that by
assuming the rapidity dependence expected for charm mesons in FONLL [40, 41]
and for charm baryons in PYTHIA 8 [17] the cross section changes by less than
$1\%$ in the measured $p_{\rm T}$ interval. Since the feed-down contribution
is not subtracted, the raw yield is divided by the inclusive acceptance-times-
efficiency factor, $(\rm Acc\times{\it\varepsilon})_{inclusive}$ and by the
integrated luminosity $\mathcal{L}_{\rm int}$ of the data sample to obtain the
production cross section. The factor $1/2$ is needed to compute the average
cross section of $\rm\Omega_{c}^{0}$ and $\rm\overline{\Omega}_{c}^{0}$. The
factor $({\rm Acc}\times{\it\varepsilon})_{\rm inclusive}$ is the product of
the geometrical acceptance (Acc) and the reconstruction and selection
efficiency ($\varepsilon$) for the
$\rm\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+}$ decay. The $({\rm
Acc}\times{\it\varepsilon})_{\rm inclusive}$ correction was obtained from a
simulation with the same configuration as the one used for the BDT training
described above. The $\rm\Omega_{c}^{0}$-baryon $p_{\rm T}$ distribution from
the simulations was reweighted in order to use realistic momentum
distributions in the determination of the acceptance and the efficiency, which
depends on $p_{\rm T}$. The weights were defined with an iterative procedure
to match the $p_{\rm T}$ dependence measured for $\rm\Omega_{c}^{0}$ baryon in
the intervals used in the analysis. In the simulation, the $\rm\Omega_{c}^{0}$
is unpolarised: it was assumed that the modification of the acceptance that
would arise from a non-zero polarisation can be considered negligible with
respect to the statistical uncertainty and the other systematic uncertainties
of the measurement. The right panel of Fig. 1 shows the final $(\rm
Acc\times{\it\varepsilon})$ correction factors of prompt, beauty feed-down,
and inclusive $\rm\Omega_{c}^{0}$ as a function of $p_{\rm T}$. They are
consistent with each other within uncertainties because the selection
variables used are not sensitive to the displacement by a few hundred
micrometers of the prompt and beauty feed-down $\rm\Omega_{c}^{0}$ decay
vertices from the collision point. The efficiency values increase with $p_{\rm
T}$ from about 0.7% to about 5%.

Figure 1: (Left panel): invariant-mass distribution of
$\rm\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+}$ candidates and their charge
conjugates integrated over the whole $p_{\rm T}$ interval 2–12 GeV$/c$. The
blue line shows the total fit function and the red line represents the
combinatorial background fit. (Right panel): acceptance-times-efficiency for
prompt, feed-down, and inclusive $\rm\Omega_{c}^{0}$ baryons decaying into
$\rm\Omega^{-}\pi^{+}$ as a function of $p_{\rm T}$ in pp collisions at
$\sqrt{s}=13$ TeV.

Systematic uncertainties were estimated considering several sources. The
uncertainty on the track reconstruction efficiency was evaluated by varying
the track selection criteria and by comparing the probability to prolong the
tracks from the TPC to the ITS hits in data and simulations. A 6% uncertainty
was assigned. The systematic uncertainty on the selection efficiency derives
from possible differences between the detector resolutions and alignment and
their description in the simulation. This uncertainty was assessed from the
comparison of the corrected yields obtained by varying the selections. In
particular, the selections on the BDT outputs were varied separately in the
different $p_{\rm T}$ intervals, with a corresponding variation of the
efficiencies ranging from 30% to 50% depending on $p_{\rm T}$. The assigned
systematic uncertainty is 10%, which represents the largest contribution to
the systematic uncertainty of the measurement. The systematic uncertainty due
to the shape of the $\rm\Omega_{c}^{0}$ $p_{\rm T}$ spectrum used in the
simulation for the calculation of the $(\rm
Acc\times{\it\varepsilon})_{inclusive}$ factor was estimated by modifying the
weights mentioned above within their uncertainties. An uncertainty of about 4%
was estimated in the $p_{\rm T}$ interval $2<p_{\rm T}<4$ GeV$/c$ and a 2%
uncertainty in $4<p_{\rm T}<12$ GeV$/c$. The systematic uncertainty on the
raw-yield extraction was evaluated in each $p_{\rm T}$ interval by repeating
the fit to the invariant-mass distributions varying the function used to
describe the background and the fit range. In order to test the sensitivity to
the line-shape of the signal, a bin-counting method was used, in which the
signal yield was obtained by integrating the invariant-mass distribution after
subtracting the combinatorial background. A 6% uncertainty was assigned
independent of $p_{\rm T}$. The sources of systematic uncertainty are assumed
to be uncorrelated among each other and the total systematic uncertainty in
each $p_{\rm T}$ interval is calculated by a quadratic sum of the individual
contributions, resulting in a 14% systematic uncertainty in $2<p_{\rm T}<4$
GeV$/c$ and 13% in $4<p_{\rm T}<12$ GeV$/c$. The production cross section has
an additional global normalisation uncertainty of 1.6% due to the integrated
luminosity determination [33].

The $p_{\rm T}$-differential production cross section of inclusive
$\rm\Omega_{c}^{0}$ baryons multiplied by the branching ratio of the
$\rm\Omega^{-}\pi^{+}$ channel measured in the rapidity interval $|y|<0.5$ and
the $p_{\rm T}$ interval $2<p_{\rm T}<12$ GeV$/c$ are shown in Fig. 2. The
feed-down contribution from $\rm\Omega_{b}^{-}$, e.g.
$\rm\Omega_{b}^{-}\rightarrow\rm\Omega_{c}^{0}+\pi^{-}$ [35], is not
subtracted because of the lack of knowledge of the branching ratios of
b-hadron decays to $\rm\Omega_{\rm c}^{0}$. Given that the efficiencies of
prompt and feed-down $\Omega_{\rm c}^{0}$ are consistent within uncertainties,
the inclusive measurement presented here preserve the original relative
abundances of its prompt and feed-down components. The data are compared with
the inclusive $\Omega_{\rm c}^{0}$ $p_{\rm T}$-differential cross sections
expected from the PYTHIA 8.243 Monash and CR-BLC tunes (Mode 2) [17, 19, 9]
multiplied by the branching ratio, $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})=(0.51^{+2.19}_{-0.31})\%$,
obtained by considering the estimate reported in Ref. [42] for the central
value, and the envelope of the values (including their uncertainties) reported
in Refs. [42, 43, 44, 45, 46, 47] to determine the uncertainty. In the $p_{\rm
T}$ interval of the measurement, the cross section from the CR-BLC tune is
larger than the one from the Monash tune by factor varying between 9 and 25
depending on $p_{\rm T}$. The Monash tune and CR-BLC tune underestimate the
data by more than 3.3$\sigma$ and 2.7$\sigma$, respectively, when $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})=0.51\%^{+2.19\%}_{-0.31\%}$ is
considered.

Figure 2: The $p_{\rm T}$-differential production cross section of inclusive
$\rm\Omega_{c}^{0}$ baryons multiplied by the branching ratio into
$\rm\Omega^{-}\pi^{+}$ for $|y|<0.5$ in pp collisions at $\sqrt{s}=13$ TeV.
The error bars and empty boxes represent the statistical and systematic
uncertainties, respectively. The measurement is compared with PYTHIA 8.243
with Monash tune [19] and with CR beyond the leading-colour approximation [9],
which are multiplied by a theoretical $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})=(0.51^{+2.19}_{-0.31})\%$ [42,
43, 44, 45, 46, 47].

The ratios of the $p_{\rm T}$-differential production cross section of
inclusive $\rm\Omega_{c}^{0}$ baryons (multiplied by the branching ratio of
the $\Omega_{\rm c}^{0}\rightarrow\Omega^{-}\pi^{+}$ decay channel) to the
prompt $\rm D^{0}$-meson cross section [3] and to the prompt $\rm\Xi_{\rm
c}^{0}$-baryon one [5] are reported in the left and right panel of Fig. 3,
respectively. The systematic uncertainties on the tracking efficiency and on
the luminosity were propagated as fully correlated in the ratios. The
uncertainties do not allow to draw a conclusion about the possible $p_{\rm T}$
dependence of the ratios. The data are compared with model expectations that
were obtained by scaling the $\Omega_{\rm c}^{0}/\rm D^{0}$ and
$\rm\Omega_{\rm c}^{0}/\Xi^{0}_{c}$ ratios predicted by the models by the BR
of the $\rm\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+}$ decay channel mentioned
above. The uncertainty band of the models represents the BR uncertainty. For
the Catania model only the specific uncertainty of the model itself are also
included in the uncertainty band [10]. In the bottom panels, the ratios of the
various models and the data to the Catania prediction are shown. The
expectations of the models differ significantly, even by orders of magnitude,
demonstrating the sensitivity of the measured ratios to the implementation of
the charm hadronisation process in the models. As visible in the left panels
of Fig. 3, the Monash [19] and CR-BLC [9] tunes of PYTHIA 8, as well as the
QCM [11] model underestimate the data significantly. The Monash tune expects a
$\rm BR(\Omega_{\rm c}^{0}\rightarrow\Omega^{-}\pi^{+})\times\Omega_{\rm
c}^{0}/\rm D^{0}$ ratio increasing with $p_{\rm T}$ from about $4\times
10^{-7}$ to about $1\times 10^{-5}$. The CR-BLC model enhances the ratio by a
factor of 12 to 34 with respect to the Monash tune. The prediction of the QCM
is larger than that of the CR-BLC model, but it is lower than the data by more
than 1.8$\sigma$. The Catania model [10] is consistent with the data. In
particular, in the version in which additional charm resonance states on top
of those listed in the PDG [35] are considered, the $\Omega_{\rm c}^{0}/\rm
D^{0}$ ratio is enhanced by a factor of 2, thus enlarging the range of
possible BR($\Omega_{\rm c}^{0}\rightarrow\Omega^{-}\pi^{+}$) values that
would allow the model prediction to be compatible within $1\sigma$ with the
data considering only the data uncertainty. The $\Omega_{\rm c}^{0}/\rm D^{0}$
ratio decreases with $p_{\rm T}$ in the measured $p_{\rm T}$ range in the CR-
BLC, QCM, and Catania models, oppositely to what is expected by Monash. In the
$\Omega_{\rm c}^{0}/\Xi_{\rm c}^{0}$ baryon-to-baryon ratio, shown in the
right panel of Fig. 3, a similar hierarchy among the model predictions is
present, though PYTHIA 8 with CR-BLC gives an enhancement by a factor of 4 to
5 with respect to the the Monash expectation, thus smaller than that of the
$\Omega_{\rm c}^{0}/\rm D^{0}$ ratio. Also for this ratio, the CR-BLC and QCM
predictions are close to each other and higher than the Monash tune. The
Catania model shows a good agreement with the data, whether the augmented set
of charm resonance states is considered or not.

Figure 3: Left, top panel: ratio of the $p_{\rm T}$-differential cross section
of $\rm\Omega_{c}^{0}$ baryons (multiplied by the branching ratio into
$\rm\Omega^{-}\pi^{+}$) to the $\rm D^{0}$-meson one [3] in $|y|<0.5$ in pp
collisions at $\sqrt{s}=13$ TeV. Right, top panel: ratio of the $p_{\rm
T}$-differential cross section of $\rm\Omega_{\rm c}^{0}$ baryons (multiplied
by the branching ratio into $\rm\Omega^{-}\pi^{+}$) to the $\rm\Xi_{\rm
c}^{0}$-baryon one [5] in $|y|<0.5$ in pp collisions at $\sqrt{s}=13$ TeV.
Bottom panels: ratio of the data and models to the Catania (coalescence plus
fragmentation) model [10]. The error bars and empty boxes represent the
statistical and systematic uncertainties, respectively. The measurements are
compared with model calculations (see text for details), which are multiplied
by a theoretical $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})=(0.51^{+2.19}_{-0.31})\%$ [42,
43, 44, 45, 46, 47].

Using the ALICE $\Xi_{\rm c}^{0}$ [5] and $\Lambda_{\rm c}^{+}$ [3] data, the
ratios $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})\times{\it\sigma}(\Omega_{c}^{0})/{\it\sigma}(\Lambda_{c}^{+})$
and $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})\times{\it\sigma}(\Omega_{c}^{0})/{\it\sigma}(\Xi_{c}^{0})$
of the cross sections integrated in the $\Omega_{\rm c}^{0}$ measured $p_{\rm
T}$ interval were obtained. They are reported in Table 1. They are compared
with the values measured in $\rm e^{+}e^{-}$ collisions at $\sqrt{s}=10.52$
GeV by Belle, obtained from the cross sections reported in Table 1 of Ref.
[28]. Though the limited $p_{\rm T}$ and rapidity ranges of the ALICE
measurement do not allow for a direct comparison of the pp and $\rm
e^{+}e^{-}$ data, the ratios observed by ALICE are larger by a factor of
$8.7\pm 2.2{\rm(stat.)}\pm 0.9{\rm(syst.)}$ and $4.7\pm 1.3{\rm(stat.)}\pm
0.5{\rm(syst.)}$ for the $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})\times{\it\sigma}(\Omega_{c}^{0})/{\it\sigma}(\Lambda_{c}^{+})$
and $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})\times{\it\sigma}(\Omega_{c}^{0})/{\it\sigma}(\Xi_{c}^{0})$,
respectively. The large BR uncertainties of the ${\rm\Xi_{c}^{0}}$ are not
propagated in the computation of this factor. This difference, along with the
comparison of data and models in Fig. 3, represents further evidence that the
hadronisation process differs in pp and $\rm e^{+}e^{-}$ collisions and is
sensitive to the density of quarks, colour charges, and on the system size.

Table 1: Ratio of the $p_{\rm T}$-integrated cross section of $\rm\Omega_{c}^{0}$ baryon (multiplied by the branching ratio into $\rm\Omega^{-}\pi^{+}$) in the interval $2<p_{\rm T}<12$ GeV$/c$ with respect to the $\rm\Lambda_{c}^{+}$\- and $\rm\Xi_{c}^{0}$-baryon cross sections measured by the ALICE [3, 5] and Belle [28] experiments in pp collisions at $\sqrt{s}=13$ TeV and $\rm e^{+}e^{-}$ collisions at $\sqrt{s}=10.52$ GeV, respectively. The first and second uncertainties represent the statistical and systematic ones. The data include the correction for the branching ratio BR($\Omega^{-}\rightarrow\Lambda{\rm K^{-}},\Lambda\rightarrow{\rm p}\pi^{-}$)=$(43.3\pm 0.6)\%$ [35]. Ratio | ALICE (pp 13 TeV) | Belle ($\rm e^{+}e^{-}$ 10.52 GeV) [28]
---|---|---
|  $2<p_{\rm T}<12$ GeV$/c$ | visible
$\rm BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})\times{\it\sigma}(\Omega_{c}^{0})/{\it\sigma}(\Lambda_{c}^{+})$ | $(1.96\pm 0.42\pm 0.13)\times 10^{-3}$ | $(2.24\pm 0.29\pm 0.16)\times 10^{-4}$
$\rm BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})\times{\it\sigma}(\Omega_{c}^{0})/{\it\sigma}(\Xi_{c}^{0})$ | $(3.99\pm 0.96\pm 0.96)\times 10^{-3}$ | $(8.58\pm 1.15\pm 1.98)\times 10^{-4}$

In summary, the inclusive $p_{\rm T}$-differential production cross section of
the charm-strange baryon $\rm\Omega_{c}^{0}$ multiplied by the branching ratio
of the $\rm\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+}$ decay channel was
measured at midrapidity ($|y|<0.5$) in pp collisions at $\sqrt{s}=13$ TeV. The
ratio of this measurement to the production cross section of the $\rm D^{0}$
meson provides further evidence that charm quarks hadronise to
$\rm\Omega_{c}^{0}$ baryons more frequently in pp collisions than in $\rm
e^{+}e^{-}$ collisions, confirming the general trend observed from previous
measurements of $\Lambda_{\rm c}^{+}$, $\Xi_{\rm c}^{0,+}$, and $\Sigma_{\rm
c}^{0,++}$ production. The large uncertainty of the $\Omega_{\rm
c}^{0}\rightarrow\Omega^{-}\pi^{+}$ branching ratio limits the effectiveness
of the comparison with theoretical models. However, the predictions of the
available models differ by large factors indicating that future measurements
of the BR, which could be performed also by the LHCb or Belle 2
collaborations, will allow to exploit these data to set stringent constraints
to theoretical models and obtain deep insight into the charm hadronisation and
the role of strange quarks and diquarks. Moreover, despite the large
uncertainties, only the Catania model, which assumes that charm-quark
hadronisation proceeds via both fragmentation and coalescence, can describe
the $\rm
BR(\Omega_{c}^{0}\rightarrow\Omega^{-}\pi^{+})\times{\it\sigma}(\Omega_{c}^{0})/{\it\sigma}(\rm
D^{0})$ ratio within uncertainties. More precise measurements with the data
sample collected in Run 3 of the LHC will allow us to further investigate the
$p_{\rm T}$ shape of the $\Omega_{\rm c}^{0}/\rm D^{0}$ and $\Omega_{\rm
c}^{0}/\Xi_{\rm c}^{0}$ ratios.

## Acknowledgements

The ALICE Collaboration would like to thank all its engineers and technicians for their invaluable contributions to the construction of the experiment and the CERN accelerator teams for the outstanding performance of the LHC complex. The ALICE Collaboration gratefully acknowledges the resources and support provided by all Grid centres and the Worldwide LHC Computing Grid (WLCG) collaboration. The ALICE Collaboration acknowledges the following funding agencies for their support in building and running the ALICE detector: A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute) Foundation (ANSL), State Committee of Science and World Federation of Scientists (WFS), Armenia; Austrian Academy of Sciences, Austrian Science Fund (FWF): [M 2467-N36] and Nationalstiftung für Forschung, Technologie und Entwicklung, Austria; Ministry of Communications and High Technologies, National Nuclear Research Center, Azerbaijan; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Financiadora de Estudos e Projetos (Finep), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Bulgarian Ministry of Education and Science, within the National Roadmap for Research Infrastructures 2020-2027 (object CERN), Bulgaria; Ministry of Education of China (MOEC) , Ministry of Science & Technology of China (MSTC) and National Natural Science Foundation of China (NSFC), China; Ministry of Science and Education and Croatian Science Foundation, Croatia; Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Cubaenergía, Cuba; Ministry of Education, Youth and Sports of the Czech Republic, Czech Republic; The Danish Council for Independent Research | Natural Sciences, the VILLUM FONDEN and Danish National Research Foundation (DNRF), Denmark; Helsinki Institute of Physics (HIP), Finland; Commissariat à l’Energie Atomique (CEA) and Institut National de Physique Nucléaire et de Physique des Particules (IN2P3) and Centre National de la Recherche Scientifique (CNRS), France; Bundesministerium für Bildung und Forschung (BMBF) and GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany; General Secretariat for Research and Technology, Ministry of Education, Research and Religions, Greece; National Research, Development and Innovation Office, Hungary; Department of Atomic Energy Government of India (DAE), Department of Science and Technology, Government of India (DST), University Grants Commission, Government of India (UGC) and Council of Scientific and Industrial Research (CSIR), India; National Research and Innovation Agency - BRIN, Indonesia; Istituto Nazionale di Fisica Nucleare (INFN), Italy; Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) and Japan Society for the Promotion of Science (JSPS) KAKENHI, Japan; Consejo Nacional de Ciencia (CONACYT) y Tecnología, through Fondo de Cooperación Internacional en Ciencia y Tecnología (FONCICYT) and Dirección General de Asuntos del Personal Academico (DGAPA), Mexico; Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO), Netherlands; The Research Council of Norway, Norway; Commission on Science and Technology for Sustainable Development in the South (COMSATS), Pakistan; Pontificia Universidad Católica del Perú, Peru; Ministry of Education and Science, National Science Centre and WUT ID-UB, Poland; Korea Institute of Science and Technology Information and National Research Foundation of Korea (NRF), Republic of Korea; Ministry of Education and Scientific Research, Institute of Atomic Physics, Ministry of Research and Innovation and Institute of Atomic Physics and University Politehnica of Bucharest, Romania; Ministry of Education, Science, Research and Sport of the Slovak Republic, Slovakia; National Research Foundation of South Africa, South Africa; Swedish Research Council (VR) and Knut & Alice Wallenberg Foundation (KAW), Sweden; European Organization for Nuclear Research, Switzerland; Suranaree University of Technology (SUT), National Science and Technology Development Agency (NSTDA) and National Science, Research and Innovation Fund (NSRF via PMU-B B05F650021), Thailand; Turkish Energy, Nuclear and Mineral Research Agency (TENMAK), Turkey; National Academy of Sciences of Ukraine, Ukraine; Science and Technology Facilities Council (STFC), United Kingdom; National Science Foundation of the United States of America (NSF) and United States Department of Energy, Office of Nuclear Physics (DOE NP), United States of America. In addition, individual groups or members have received support from: Marie Skłodowska Curie, European Research Council, Strong 2020 - Horizon 2020 (grant nos. 950692, 824093, 896850), European Union; Academy of Finland (Center of Excellence in Quark Matter) (grant nos. 346327, 346328), Finland; Programa de Apoyos para la Superación del Personal Académico, UNAM, Mexico.

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##  Appendix A The ALICE Collaboration

S. Acharya 124,132, D. Adamová 85, A. Adler69, G. Aglieri Rinella 32, M.
Agnello 29, N. Agrawal 50, Z. Ahammed 132, S. Ahmad 15, S.U. Ahn 70, I. Ahuja
37, A. Akindinov 140, M. Al-Turany 97, D. Aleksandrov 140, B. Alessandro 55,
H.M. Alfanda 6, R. Alfaro Molina 66, B. Ali 15, Y. Ali13, A. Alici 25, N.
Alizadehvandchali 113, A. Alkin 32, J. Alme 20, G. Alocco 51, T. Alt 63, I.
Altsybeev 140, M.N. Anaam 6, C. Andrei 45, A. Andronic 135, V. Anguelov 94, F.
Antinori 53, P. Antonioli 50, C. Anuj 15, N. Apadula 73, L. Aphecetche 103, H.
Appelshäuser 63, C. Arata 72, S. Arcelli 25, R. Arnaldi 55, I.C. Arsene 19, M.
Arslandok 137, A. Augustinus 32, R. Averbeck 97, S. Aziz 128, M.D. Azmi 15, A.
Badalà 52, Y.W. Baek 40, X. Bai 117, R. Bailhache 63, Y. Bailung 47, R. Bala
90, A. Balbino 29, A. Baldisseri 127, B. Balis 2, D. Banerjee 4, Z. Banoo 90,
R. Barbera 26, L. Barioglio 95, M. Barlou77, G.G. Barnaföldi 136, L.S. Barnby
84, V. Barret 124, L. Barreto 109, C. Bartels 116, K. Barth 32, E. Bartsch 63,
F. Baruffaldi 27, N. Bastid 124, S. Basu 74, G. Batigne 103, D. Battistini 95,
B. Batyunya 141, D. Bauri46, J.L. Bazo Alba 101, I.G. Bearden 82, C. Beattie
137, P. Becht 97, D. Behera 47, I. Belikov 126, A.D.C. Bell Hechavarria 135,
F. Bellini 25, R. Bellwied 113, S. Belokurova 140, V. Belyaev 140, G. Bencedi
136,64, S. Beole 24, A. Bercuci 45, Y. Berdnikov 140, A. Berdnikova 94, L.
Bergmann 94, M.G. Besoiu 62, L. Betev 32, P.P. Bhaduri 132, A. Bhasin 90, M.A.
Bhat 4, B. Bhattacharjee 41, L. Bianchi 24, N. Bianchi 48, J. Bielčík 35, J.
Bielčíková 85, J. Biernat 106, A.P. Bigot 126, A. Bilandzic 95, G. Biro 136,
S. Biswas 4, N. Bize 103, J.T. Blair 107, D. Blau 140, M.B. Blidaru 97, N.
Bluhme38, C. Blume 63, G. Boca 21,54, F. Bock 86, T. Bodova 20, A.
Bogdanov140, S. Boi 22, J. Bok 57, L. Boldizsár 136, A. Bolozdynya 140, M.
Bombara 37, P.M. Bond 32, G. Bonomi 131,54, H. Borel 127, A. Borissov 140, H.
Bossi 137, E. Botta 24, L. Bratrud 63, P. Braun-Munzinger 97, M. Bregant 109,
M. Broz 35, G.E. Bruno 96,31, M.D. Buckland 116, D. Budnikov 140, H. Buesching
63, S. Bufalino 29, O. Bugnon103, P. Buhler 102, Z. Buthelezi 67,120, J.B.
Butt13, A. Bylinkin 115, S.A. Bysiak106, M. Cai 27,6, H. Caines 137, A. Caliva
97, E. Calvo Villar 101, J.M.M. Camacho 108, P. Camerini 23, F.D.M. Canedo
109, M. Carabas 123, F. Carnesecchi 32, R. Caron 125, J. Castillo Castellanos
127, F. Catalano 29, C. Ceballos Sanchez 141, I. Chakaberia 73, P. Chakraborty
46, S. Chandra 132, S. Chapeland 32, M. Chartier 116, S. Chattopadhyay 132, S.
Chattopadhyay 99, T.G. Chavez 44, T. Cheng 6, C. Cheshkov 125, B. Cheynis 125,
V. Chibante Barroso 32, D.D. Chinellato 110, E.S. Chizzali II,95, J. Cho 57,
S. Cho 57, P. Chochula 32, P. Christakoglou 83, C.H. Christensen 82, P.
Christiansen 74, T. Chujo 122, M. Ciacco 29, C. Cicalo 51, L. Cifarelli 25, F.
Cindolo 50, M.R. Ciupek97, G. ClaiIII,50, F. Colamaria 49, J.S. Colburn100, D.
Colella 96,31, A. Collu73, M. Colocci 32, M. Concas IV,55, G. Conesa Balbastre
72, Z. Conesa del Valle 128, G. Contin 23, J.G. Contreras 35, M.L. Coquet 127,
T.M. CormierI,86, P. Cortese 130,55, M.R. Cosentino 111, F. Costa 32, S.
Costanza 21,54, P. Crochet 124, R. Cruz-Torres 73, E. Cuautle64, P. Cui 6, L.
Cunqueiro86, A. Dainese 53, M.C. Danisch 94, A. Danu 62, P. Das 79, P. Das 4,
S. Das 4, A.R. Dash 135, S. Dash 46, R.M.H. David44, A. De Caro 28, G. de
Cataldo 49, L. De Cilladi 24, J. de Cuveland38, A. De Falco 22, D. De Gruttola
28, N. De Marco 55, C. De Martin 23, S. De Pasquale 28, S. Deb 47, H.F.
Degenhardt109, K.R. Deja133, R. Del Grande 95, L. Dello Stritto 28, W. Deng 6,
P. Dhankher 18, D. Di Bari 31, A. Di Mauro 32, R.A. Diaz 141,7, T. Dietel 112,
Y. Ding 125,6, R. Divià 32, D.U. Dixit 18, Ø. Djuvsland20, U. Dmitrieva 140,
A. Dobrin 62, B. Dönigus 63, A.K. Dubey 132, J.M. Dubinski 133, A. Dubla 97,
S. Dudi 89, P. Dupieux 124, M. Durkac105, N. Dzalaiova12, T.M. Eder 135, R.J.
Ehlers 86, V.N. Eikeland20, F. Eisenhut 63, D. Elia 49, B. Erazmus 103, F.
Ercolessi 25, F. Erhardt 88, M.R. Ersdal20, B. Espagnon 128, G. Eulisse 32, D.
Evans 100, S. Evdokimov 140, L. Fabbietti 95, M. Faggin 27, J. Faivre 72, F.
Fan 6, W. Fan 73, A. Fantoni 48, M. Fasel 86, P. Fecchio29, A. Feliciello 55,
G. Feofilov 140, A. Fernández Téllez 44, M.B. Ferrer 32, A. Ferrero 127, A.
Ferretti 24, V.J.G. Feuillard 94, J. Figiel 106, V. Filova 35, D. Finogeev
140, F.M. Fionda 51, G. Fiorenza96, F. Flor 113, A.N. Flores 107, S. Foertsch
67, I. Fokin 94, S. Fokin 140, E. Fragiacomo 56, E. Frajna 136, U. Fuchs 32,
N. Funicello 28, C. Furget 72, A. Furs 140, T. Fusayasu 98, J.J. Gaardhøje 82,
M. Gagliardi 24, A.M. Gago 101, A. Gal126, C.D. Galvan 108, D.R. Gangadharan
113, P. Ganoti 77, C. Garabatos 97, J.R.A. Garcia 44, E. Garcia-Solis 9, K.
Garg 103, C. Gargiulo 32, A. Garibli80, K. Garner135, A. Gautam 115, M.B. Gay
Ducati 65, M. Germain 103, C. Ghosh132, S.K. Ghosh4, M. Giacalone 25, P.
Gianotti 48, P. Giubellino 97,55, P. Giubilato 27, A.M.C. Glaenzer 127, P.
Glässel 94, E. Glimos 119, D.J.Q. Goh75, V. Gonzalez 134, L.H. González-Trueba
66, M. Gorgon 2, L. Görlich 106, S. Gotovac33, V. Grabski 66, L.K.
Graczykowski 133, E. Grecka 85, L. Greiner 73, A. Grelli 58, C. Grigoras 32,
V. Grigoriev 140, S. Grigoryan 141,1, F. Grosa 32, J.F. Grosse-Oetringhaus 32,
R. Grosso 97, D. Grund 35, G.G. Guardiano 110, R. Guernane 72, M. Guilbaud
103, K. Gulbrandsen 82, T. Gunji 121, W. Guo 6, A. Gupta 90, R. Gupta 90, S.P.
Guzman 44, L. Gyulai 136, M.K. Habib97, C. Hadjidakis 128, H. Hamagaki 75, M.
Hamid6, Y. Han 138, R. Hannigan 107, M.R. Haque 133, A. Harlenderova97, J.W.
Harris 137, A. Harton 9, H. Hassan 86, D. Hatzifotiadou 50, P. Hauer 42, L.B.
Havener 137, S.T. Heckel 95, E. Hellbär 97, H. Helstrup 34, T. Herman 35, G.
Herrera Corral 8, F. Herrmann135, S. Herrmann 125, K.F. Hetland 34, B. Heybeck
63, H. Hillemanns 32, C. Hills 116, B. Hippolyte 126, B. Hofman 58, B.
Hohlweger 83, J. Honermann 135, G.H. Hong 138, D. Horak 35, A. Horzyk 2, R.
Hosokawa14, Y. Hou 6, P. Hristov 32, C. Hughes 119, P. Huhn63, L.M. Huhta 114,
C.V. Hulse 128, T.J. Humanic 87, H. Hushnud99, A. Hutson 113, D. Hutter 38,
J.P. Iddon 116, R. Ilkaev140, H. Ilyas 13, M. Inaba 122, G.M. Innocenti 32, M.
Ippolitov 140, A. Isakov 85, T. Isidori 115, M.S. Islam 99, M. Ivanov 97, M.
Ivanov12, V. Ivanov 140, V. Izucheev140, M. Jablonski 2, B. Jacak 73, N.
Jacazio 32, P.M. Jacobs 73, S. Jadlovska105, J. Jadlovsky105, S. Jaelani81, L.
Jaffe38, C. Jahnke 110, M.A. Janik 133, T. Janson69, M. Jercic88, O.
Jevons100, A.A.P. Jimenez 64, F. Jonas 86, P.G. Jones100, J.M. Jowett 32,97,
J. Jung 63, M. Jung 63, A. Junique 32, A. Jusko 100, M.J. Kabus 32,133, J.
Kaewjai104, P. Kalinak 59, A.S. Kalteyer 97, A. Kalweit 32, V. Kaplin 140, A.
Karasu Uysal 71, D. Karatovic 88, O. Karavichev 140, T. Karavicheva 140, P.
Karczmarczyk 133, E. Karpechev 140, V. Kashyap79, A. Kazantsev140, U.
Kebschull 69, R. Keidel 139, D.L.D. Keijdener58, M. Keil 32, B. Ketzer 42,
A.M. Khan 6, S. Khan 15, A. Khanzadeev 140, Y. Kharlov 140, A. Khatun 15, A.
Khuntia 106, B. Kileng 34, B. Kim 16, C. Kim 16, D.J. Kim 114, E.J. Kim 68, J.
Kim 138, J.S. Kim 40, J. Kim 94, J. Kim 68, M. Kim 94, S. Kim 17, T. Kim 138,
K. Kimura 92, S. Kirsch 63, I. Kisel 38, S. Kiselev 140, A. Kisiel 133, J.P.
Kitowski 2, J.L. Klay 5, J. Klein 32, S. Klein 73, C. Klein-Bösing 135, M.
Kleiner 63, T. Klemenz 95, A. Kluge 32, A.G. Knospe 113, C. Kobdaj 104, T.
Kollegger97, A. Kondratyev 141, E. Kondratyuk 140, J. Konig 63, S.A.
Konigstorfer 95, P.J. Konopka 32, G. Kornakov 133, S.D. Koryciak 2, A.
Kotliarov 85, O. Kovalenko 78, V. Kovalenko 140, M. Kowalski 106, I. Králik
59, A. Kravčáková 37, L. Kreis97, M. Krivda 100,59, F. Krizek 85, K. Krizkova
Gajdosova 35, M. Kroesen 94, M. Krüger 63, D.M. Krupova 35, E. Kryshen 140, M.
Krzewicki38, V. Kučera 32, C. Kuhn 126, P.G. Kuijer 83, T. Kumaoka122, D.
Kumar132, L. Kumar 89, N. Kumar89, S. Kundu 32, P. Kurashvili 78, A. Kurepin
140, A.B. Kurepin 140, S. Kushpil 85, J. Kvapil 100, M.J. Kweon 57, J.Y. Kwon
57, Y. Kwon 138, S.L. La Pointe 38, P. La Rocca 26, Y.S. Lai73, A.
Lakrathok104, M. Lamanna 32, R. Langoy 118, P. Larionov 48, E. Laudi 32, L.
Lautner 32,95, R. Lavicka 102, T. Lazareva 140, R. Lea 131,54, G. Legras 135,
J. Lehrbach 38, R.C. Lemmon 84, I. León Monzón 108, M.M. Lesch 95, E.D. Lesser
18, M. Lettrich95, P. Lévai 136, X. Li10, X.L. Li6, J. Lien 118, R. Lietava
100, B. Lim 16, S.H. Lim 16, V. Lindenstruth 38, A. Lindner45, C. Lippmann 97,
A. Liu 18, D.H. Liu 6, J. Liu 116, I.M. Lofnes 20, C. Loizides 86, P. Loncar
33, J.A. Lopez 94, X. Lopez 124, E. López Torres 7, P. Lu 97,117, J.R. Luhder
135, M. Lunardon 27, G. Luparello 56, Y.G. Ma 39, A. Maevskaya140, M. Mager
32, T. Mahmoud42, A. Maire 126, M. Malaev 140, G. Malfattore 25, N.M. Malik
90, Q.W. Malik19, S.K. Malik 90, L. Malinina VII,141, D. Mal’Kevich 140, D.
Mallick 79, N. Mallick 47, G. Mandaglio 30,52, V. Manko 140, F. Manso 124, V.
Manzari 49, Y. Mao 6, G.V. Margagliotti 23, A. Margotti 50, A. Marín 97, C.
Markert 107, M. Marquard63, P. Martinengo 32, J.L. Martinez113, M.I. Martínez
44, G. Martínez García 103, S. Masciocchi 97, M. Masera 24, A. Masoni 51, L.
Massacrier 128, A. Mastroserio 129,49, A.M. Mathis 95, O. Matonoha 74, P.F.T.
Matuoka109, A. Matyja 106, C. Mayer 106, A.L. Mazuecos 32, F. Mazzaschi 24, M.
Mazzilli 32, J.E. Mdhluli 120, A.F. Mechler63, Y. Melikyan 140, A. Menchaca-
Rocha 66, E. Meninno 102,28, A.S. Menon 113, M. Meres 12, S. Mhlanga112,67, Y.
Miake122, L. Micheletti 55, L.C. Migliorin125, D.L. Mihaylov 95, K. Mikhaylov
141,140, A.N. Mishra 136, D. Miśkowiec 97, A. Modak 4, A.P. Mohanty 58, B.
Mohanty79, M. Mohisin Khan V,15, M.A. Molander 43, Z. Moravcova 82, C.
Mordasini 95, D.A. Moreira De Godoy 135, I. Morozov 140, A. Morsch 32, T.
Mrnjavac 32, V. Muccifora 48, E. Mudnic33, S. Muhuri 132, J.D. Mulligan 73, A.
Mulliri22, M.G. Munhoz 109, R.H. Munzer 63, H. Murakami 121, S. Murray 112, L.
Musa 32, J. Musinsky 59, J.W. Myrcha 133, B. Naik 120, R. Nair 78, A.I.
Nambrath 18, B.K. Nandi 46, R. Nania 50, E. Nappi 49, A.F. Nassirpour 74, A.
Nath 94, C. Nattrass 119, A. Neagu19, A. Negru123, L. Nellen 64, S.V. Nesbo34,
G. Neskovic 38, D. Nesterov 140, B.S. Nielsen 82, E.G. Nielsen 82, S. Nikolaev
140, S. Nikulin 140, V. Nikulin 140, F. Noferini 50, S. Noh 11, P. Nomokonov
141, J. Norman 116, N. Novitzky 122, P. Nowakowski 133, A. Nyanin 140, J.
Nystrand 20, M. Ogino 75, A. Ohlson 74, V.A. Okorokov 140, J. Oleniacz 133,
A.C. Oliveira Da Silva 119, M.H. Oliver 137, A. Onnerstad 114, C. Oppedisano
55, A. Ortiz Velasquez 64, A. Oskarsson74, J. Otwinowski 106, M. Oya92, K.
Oyama 75, Y. Pachmayer 94, S. Padhan 46, D. Pagano 131,54, G. Paić 64, A.
Palasciano 49, S. Panebianco 127, H. Park 122, J. Park 57, J.E. Parkkila
32,114, S.P. Pathak113, R.N. Patra90, B. Paul 22, H. Pei 6, T. Peitzmann 58,
X. Peng 6, M. Pennisi 24, L.G. Pereira 65, H. Pereira Da Costa 127, D.
Peresunko 140, G.M. Perez 7, S. Perrin 127, Y. Pestov140, V. Petráček 35, V.
Petrov 140, M. Petrovici 45, R.P. Pezzi 103,65, S. Piano 56, M. Pikna 12, P.
Pillot 103, O. Pinazza 50,32, L. Pinsky113, C. Pinto 95, S. Pisano 48, M.
Płoskoń 73, M. Planinic88, F. Pliquett63, M.G. Poghosyan 86, S. Politano 29,
N. Poljak 88, A. Pop 45, S. Porteboeuf-Houssais 124, J. Porter 73, V.
Pozdniakov 141, S.K. Prasad 4, S. Prasad 47, R. Preghenella 50, F. Prino 55,
C.A. Pruneau 134, I. Pshenichnov 140, M. Puccio 32, S. Pucillo 24, Z.
Pugelova105, S. Qiu 83, L. Quaglia 24, R.E. Quishpe113, S. Ragoni 100, A.
Rakotozafindrabe 127, L. Ramello 130,55, F. Rami 126, S.A.R. Ramirez 44, T.A.
Rancien72, R. Raniwala 91, S. Raniwala91, S.S. Räsänen 43, R. Rath 50,47, I.
Ravasenga 83, K.F. Read 86,119, A.R. Redelbach 38, K. Redlich VI,78, A.
Rehman20, P. Reichelt63, F. Reidt 32, H.A. Reme-Ness 34, Z. Rescakova37, K.
Reygers 94, A. Riabov 140, V. Riabov 140, R. Ricci 28, T. Richert74, M.
Richter 19, A.A. Riedel 95, W. Riegler 32, F. Riggi 26, C. Ristea 62, M.
Rodríguez Cahuantzi 44, K. Røed 19, R. Rogalev 140, E. Rogochaya 141, T.S.
Rogoschinski 63, D. Rohr 32, D. Röhrich 20, P.F. Rojas44, S. Rojas Torres 35,
P.S. Rokita 133, G. Romanenko 141, F. Ronchetti 48, A. Rosano 30,52, E.D.
Rosas64, A. Rossi 53, A. Roy 47, P. Roy99, S. Roy 46, N. Rubini 25, D.
Ruggiano 133, R. Rui 23, B. Rumyantsev141, P.G. Russek 2, R. Russo 83, A.
Rustamov 80, E. Ryabinkin 140, Y. Ryabov 140, A. Rybicki 106, H. Rytkonen 114,
W. Rzesa 133, O.A.M. Saarimaki 43, R. Sadek 103, S. Sadovsky 140, J. Saetre
20, K. Šafařík 35, S. Saha 79, B. Sahoo 46, R. Sahoo 47, S. Sahoo60, D. Sahu
47, P.K. Sahu 60, J. Saini 132, K. Sajdakova37, S. Sakai 122, M.P. Salvan 97,
S. Sambyal 90, T.B. Saramela109, D. Sarkar 134, N. Sarkar132, P. Sarma 41, V.
Sarritzu 22, V.M. Sarti 95, M.H.P. Sas 137, J. Schambach 86, H.S. Scheid 63,
C. Schiaua 45, R. Schicker 94, A. Schmah94, C. Schmidt 97, H.R. Schmidt93,
M.O. Schmidt 32, M. Schmidt93, N.V. Schmidt 86, A.R. Schmier 119, R. Schotter
126, J. Schukraft 32, K. Schwarz97, K. Schweda 97, G. Scioli 25, E. Scomparin
55, J.E. Seger 14, Y. Sekiguchi121, D. Sekihata 121, I. Selyuzhenkov 97,140,
S. Senyukov 126, J.J. Seo 57, D. Serebryakov 140, L. Šerkšnytė 95, A. Sevcenco
62, T.J. Shaba 67, A. Shabetai 103, R. Shahoyan32, A. Shangaraev 140, A.
Sharma89, D. Sharma 46, H. Sharma 106, M. Sharma 90, N. Sharma 89, S. Sharma
75, S. Sharma 90, U. Sharma 90, A. Shatat 128, O. Sheibani113, K. Shigaki 92,
M. Shimomura76, S. Shirinkin 140, Q. Shou 39, Y. Sibiriak 140, S. Siddhanta
51, T. Siemiarczuk 78, T.F. Silva 109, D. Silvermyr 74, T.
Simantathammakul104, R. Simeonov 36, G. Simonetti32, B. Singh90, B. Singh 95,
R. Singh 79, R. Singh 90, R. Singh 47, S. Singh 15, V.K. Singh 132, V. Singhal
132, T. Sinha 99, B. Sitar 12, M. Sitta 130,55, T.B. Skaali19, G. Skorodumovs
94, M. Slupecki 43, N. Smirnov 137, R.J.M. Snellings 58, E.H. Solheim 19, C.
Soncco101, J. Song 113, A. Songmoolnak104, F. Soramel 27, S.P. Sorensen 119,
R. Spijkers 83, I. Sputowska 106, J. Staa 74, J. Stachel 94, I. Stan 62, P.J.
Steffanic 119, S.F. Stiefelmaier 94, D. Stocco 103, I. Storehaug 19, M.M.
Storetvedt 34, P. Stratmann 135, S. Strazzi 25, C.P. Stylianidis83, A.A.P.
Suaide 109, C. Suire 128, M. Sukhanov 140, M. Suljic 32, V. Sumberia 90, S.
Sumowidagdo 81, S. Swain60, I. Szarka 12, U. Tabassam13, S.F. Taghavi 95, G.
Taillepied 97, J. Takahashi 110, G.J. Tambave 20, S. Tang 124,6, Z. Tang 117,
J.D. Tapia Takaki 115, N. Tapus123, L.A. Tarasovicova 135, M.G. Tarzila 45,
G.F. Tassielli 31, A. Tauro 32, A. Telesca 32, L. Terlizzi 24, C. Terrevoli
113, G. Tersimonov3, D. Thomas 107, A. Tikhonov 140, A.R. Timmins 113, M.
Tkacik105, T. Tkacik 105, A. Toia 63, R. Tokumoto92, N. Topilskaya 140, M.
Toppi 48, F. Torales-Acosta18, T. Tork 128, A.G. Torres Ramos 31, A. Trifiró
30,52, A.S. Triolo 30,52, S. Tripathy 50, T. Tripathy 46, S. Trogolo 32, V.
Trubnikov 3, W.H. Trzaska 114, T.P. Trzcinski 133, R. Turrisi 53, T.S. Tveter
19, K. Ullaland 20, B. Ulukutlu 95, A. Uras 125, M. Urioni 54,131, G.L. Usai
22, M. Vala37, N. Valle 21, S. Vallero 55, L.V.R. van Doremalen58, M. van
Leeuwen 83, C.A. van Veen 94, R.J.G. van Weelden 83, P. Vande Vyvre 32, D.
Varga 136, Z. Varga 136, M. Varga-Kofarago 136, M. Vasileiou 77, A. Vasiliev
140, O. Vázquez Doce 95, O. Vazquez Rueda 74, V. Vechernin 140, E. Vercellin
24, S. Vergara Limón44, L. Vermunt 97, R. Vértesi 136, M. Verweij 58, L.
Vickovic33, Z. Vilakazi120, O. Villalobos Baillie 100, G. Vino 49, A.
Vinogradov 140, T. Virgili 28, V. Vislavicius82, A. Vodopyanov 141, B. Volkel
32, M.A. Völkl 94, K. Voloshin140, S.A. Voloshin 134, G. Volpe 31, B. von
Haller 32, I. Vorobyev 95, N. Vozniuk 140, J. Vrláková 37, B. Wagner20, C.
Wang 39, D. Wang39, M. Weber 102, A. Wegrzynek 32, F.T. Weiglhofer38, S.C.
Wenzel 32, J.P. Wessels 135, S.L. Weyhmiller 137, J. Wiechula 63, J. Wikne 19,
G. Wilk 78, J. Wilkinson 97, G.A. Willems 135, B. Windelband 94, M. Winn 127,
J.R. Wright 107, W. Wu39, Y. Wu 117, R. Xu 6, A. Yadav 42, A.K. Yadav 132, S.
Yalcin 71, Y. Yamaguchi 92, K. Yamakawa92, S. Yang20, S. Yano 92, Z. Yin 6,
I.-K. Yoo 16, J.H. Yoon 57, S. Yuan20, A. Yuncu 94, V. Zaccolo 23, C. Zampolli
32, H.J.C. Zanoli58, F. Zanone 94, N. Zardoshti 32,100, A. Zarochentsev 140,
P. Závada 61, N. Zaviyalov140, M. Zhalov 140, B. Zhang 6, S. Zhang 39, X.
Zhang 6, Y. Zhang117, Z. Zhang 6, M. Zhao 10, V. Zherebchevskii 140, Y. Zhi10,
N. Zhigareva140, D. Zhou 6, Y. Zhou 82, J. Zhu 6,97, Y. Zhu6, G. ZinovjevI,3,
N. Zurlo 131,54

## Affiliation Notes

I Deceased
II Also at: Max-Planck-Institut für Physik, Munich, Germany
III Also at: Italian National Agency for New Technologies, Energy and
Sustainable Economic Development (ENEA), Bologna, Italy
IV Also at: Dipartimento DET del Politecnico di Torino, Turin, Italy
V Also at: Department of Applied Physics, Aligarh Muslim University, Aligarh,
India
VI Also at: Institute of Theoretical Physics, University of Wroclaw, Poland
VII Also at: An institution covered by a cooperation agreement with CERN

## Collaboration Institutes

1 A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute)
Foundation, Yerevan, Armenia
2 AGH University of Krakow, Cracow, Poland
3 Bogolyubov Institute for Theoretical Physics, National Academy of Sciences
of Ukraine, Kiev, Ukraine
4 Bose Institute, Department of Physics and Centre for Astroparticle Physics
and Space Science (CAPSS), Kolkata, India
5 California Polytechnic State University, San Luis Obispo, California, United
States
6 Central China Normal University, Wuhan, China
7 Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Havana,
Cuba
8 Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City and
Mérida, Mexico
9 Chicago State University, Chicago, Illinois, United States
10 China Institute of Atomic Energy, Beijing, China
11 Chungbuk National University, Cheongju, Republic of Korea
12 Comenius University Bratislava, Faculty of Mathematics, Physics and
Informatics, Bratislava, Slovak Republic
13 COMSATS University Islamabad, Islamabad, Pakistan
14 Creighton University, Omaha, Nebraska, United States
15 Department of Physics, Aligarh Muslim University, Aligarh, India
16 Department of Physics, Pusan National University, Pusan, Republic of Korea
17 Department of Physics, Sejong University, Seoul, Republic of Korea
18 Department of Physics, University of California, Berkeley, California,
United States
19 Department of Physics, University of Oslo, Oslo, Norway
20 Department of Physics and Technology, University of Bergen, Bergen, Norway
21 Dipartimento di Fisica, Università di Pavia, Pavia, Italy
22 Dipartimento di Fisica dell’Università and Sezione INFN, Cagliari, Italy
23 Dipartimento di Fisica dell’Università and Sezione INFN, Trieste, Italy
24 Dipartimento di Fisica dell’Università and Sezione INFN, Turin, Italy
25 Dipartimento di Fisica e Astronomia dell’Università and Sezione INFN,
Bologna, Italy
26 Dipartimento di Fisica e Astronomia dell’Università and Sezione INFN,
Catania, Italy
27 Dipartimento di Fisica e Astronomia dell’Università and Sezione INFN,
Padova, Italy
28 Dipartimento di Fisica ‘E.R. Caianiello’ dell’Università and Gruppo
Collegato INFN, Salerno, Italy
29 Dipartimento DISAT del Politecnico and Sezione INFN, Turin, Italy
30 Dipartimento di Scienze MIFT, Università di Messina, Messina, Italy
31 Dipartimento Interateneo di Fisica ‘M. Merlin’ and Sezione INFN, Bari,
Italy
32 European Organization for Nuclear Research (CERN), Geneva, Switzerland
33 Faculty of Electrical Engineering, Mechanical Engineering and Naval
Architecture, University of Split, Split, Croatia
34 Faculty of Engineering and Science, Western Norway University of Applied
Sciences, Bergen, Norway
35 Faculty of Nuclear Sciences and Physical Engineering, Czech Technical
University in Prague, Prague, Czech Republic
36 Faculty of Physics, Sofia University, Sofia, Bulgaria
37 Faculty of Science, P.J. Šafárik University, Košice, Slovak Republic
38 Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe-
Universität Frankfurt, Frankfurt, Germany
39 Fudan University, Shanghai, China
40 Gangneung-Wonju National University, Gangneung, Republic of Korea
41 Gauhati University, Department of Physics, Guwahati, India
42 Helmholtz-Institut für Strahlen- und Kernphysik, Rheinische Friedrich-
Wilhelms-Universität Bonn, Bonn, Germany
43 Helsinki Institute of Physics (HIP), Helsinki, Finland
44 High Energy Physics Group, Universidad Autónoma de Puebla, Puebla, Mexico
45 Horia Hulubei National Institute of Physics and Nuclear Engineering,
Bucharest, Romania
46 Indian Institute of Technology Bombay (IIT), Mumbai, India
47 Indian Institute of Technology Indore, Indore, India
48 INFN, Laboratori Nazionali di Frascati, Frascati, Italy
49 INFN, Sezione di Bari, Bari, Italy
50 INFN, Sezione di Bologna, Bologna, Italy
51 INFN, Sezione di Cagliari, Cagliari, Italy
52 INFN, Sezione di Catania, Catania, Italy
53 INFN, Sezione di Padova, Padova, Italy
54 INFN, Sezione di Pavia, Pavia, Italy
55 INFN, Sezione di Torino, Turin, Italy
56 INFN, Sezione di Trieste, Trieste, Italy
57 Inha University, Incheon, Republic of Korea
58 Institute for Gravitational and Subatomic Physics (GRASP), Utrecht
University/Nikhef, Utrecht, Netherlands
59 Institute of Experimental Physics, Slovak Academy of Sciences, Košice,
Slovak Republic
60 Institute of Physics, Homi Bhabha National Institute, Bhubaneswar, India
61 Institute of Physics of the Czech Academy of Sciences, Prague, Czech
Republic
62 Institute of Space Science (ISS), Bucharest, Romania
63 Institut für Kernphysik, Johann Wolfgang Goethe-Universität Frankfurt,
Frankfurt, Germany
64 Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México,
Mexico City, Mexico
65 Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS),
Porto Alegre, Brazil
66 Instituto de Física, Universidad Nacional Autónoma de México, Mexico City,
Mexico
67 iThemba LABS, National Research Foundation, Somerset West, South Africa
68 Jeonbuk National University, Jeonju, Republic of Korea
69 Johann-Wolfgang-Goethe Universität Frankfurt Institut für Informatik,
Fachbereich Informatik und Mathematik, Frankfurt, Germany
70 Korea Institute of Science and Technology Information, Daejeon, Republic of
Korea
71 KTO Karatay University, Konya, Turkey
72 Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-
Alpes, CNRS-IN2P3, Grenoble, France
73 Lawrence Berkeley National Laboratory, Berkeley, California, United States
74 Lund University Department of Physics, Division of Particle Physics, Lund,
Sweden
75 Nagasaki Institute of Applied Science, Nagasaki, Japan
76 Nara Women’s University (NWU), Nara, Japan
77 National and Kapodistrian University of Athens, School of Science,
Department of Physics , Athens, Greece
78 National Centre for Nuclear Research, Warsaw, Poland
79 National Institute of Science Education and Research, Homi Bhabha National
Institute, Jatni, India
80 National Nuclear Research Center, Baku, Azerbaijan
81 National Research and Innovation Agency - BRIN, Jakarta, Indonesia
82 Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
83 Nikhef, National institute for subatomic physics, Amsterdam, Netherlands
84 Nuclear Physics Group, STFC Daresbury Laboratory, Daresbury, United Kingdom
85 Nuclear Physics Institute of the Czech Academy of Sciences, Husinec-Řež,
Czech Republic
86 Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States
87 Ohio State University, Columbus, Ohio, United States
88 Physics department, Faculty of science, University of Zagreb, Zagreb,
Croatia
89 Physics Department, Panjab University, Chandigarh, India
90 Physics Department, University of Jammu, Jammu, India
91 Physics Department, University of Rajasthan, Jaipur, India
92 Physics Program and International Institute for Sustainability with Knotted
Chiral Meta Matter (SKCM2), Hiroshima University, Hiroshima, Japan
93 Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Tübingen,
Germany
94 Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg,
Germany
95 Physik Department, Technische Universität München, Munich, Germany
96 Politecnico di Bari and Sezione INFN, Bari, Italy
97 Research Division and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum
für Schwerionenforschung GmbH, Darmstadt, Germany
98 Saga University, Saga, Japan
99 Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Kolkata,
India
100 School of Physics and Astronomy, University of Birmingham, Birmingham,
United Kingdom
101 Sección Física, Departamento de Ciencias, Pontificia Universidad Católica
del Perú, Lima, Peru
102 Stefan Meyer Institut für Subatomare Physik (SMI), Vienna, Austria
103 SUBATECH, IMT Atlantique, Nantes Université, CNRS-IN2P3, Nantes, France
104 Suranaree University of Technology, Nakhon Ratchasima, Thailand
105 Technical University of Košice, Košice, Slovak Republic
106 The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of
Sciences, Cracow, Poland
107 The University of Texas at Austin, Austin, Texas, United States
108 Universidad Autónoma de Sinaloa, Culiacán, Mexico
109 Universidade de São Paulo (USP), São Paulo, Brazil
110 Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
111 Universidade Federal do ABC, Santo Andre, Brazil
112 University of Cape Town, Cape Town, South Africa
113 University of Houston, Houston, Texas, United States
114 University of Jyväskylä, Jyväskylä, Finland
115 University of Kansas, Lawrence, Kansas, United States
116 University of Liverpool, Liverpool, United Kingdom
117 University of Science and Technology of China, Hefei, China
118 University of South-Eastern Norway, Kongsberg, Norway
119 University of Tennessee, Knoxville, Tennessee, United States
120 University of the Witwatersrand, Johannesburg, South Africa
121 University of Tokyo, Tokyo, Japan
122 University of Tsukuba, Tsukuba, Japan
123 University Politehnica of Bucharest, Bucharest, Romania
124 Université Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand, France
125 Université de Lyon, CNRS/IN2P3, Institut de Physique des 2 Infinis de
Lyon, Lyon, France
126 Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France,
Strasbourg, France
127 Université Paris-Saclay, Centre d’Etudes de Saclay (CEA), IRFU, Départment
de Physique Nucléaire (DPhN), Saclay, France
128 Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
129 Università degli Studi di Foggia, Foggia, Italy
130 Università del Piemonte Orientale, Vercelli, Italy
131 Università di Brescia, Brescia, Italy
132 Variable Energy Cyclotron Centre, Homi Bhabha National Institute, Kolkata,
India
133 Warsaw University of Technology, Warsaw, Poland
134 Wayne State University, Detroit, Michigan, United States
135 Westfälische Wilhelms-Universität Münster, Institut für Kernphysik,
Münster, Germany
136 Wigner Research Centre for Physics, Budapest, Hungary
137 Yale University, New Haven, Connecticut, United States
138 Yonsei University, Seoul, Republic of Korea
139 Zentrum für Technologie und Transfer (ZTT), Worms, Germany
140 Affiliated with an institute covered by a cooperation agreement with CERN
141 Affiliated with an international laboratory covered by a cooperation
agreement with CERN.