HIN-17-007

$HeadURL$ $Id$

HIN-17-007

# Observation of nuclear modifications in boson production in $\Pp\text{Pb}$
collisions at $\sqrtsNN=8.16\TeV$

###### Abstract

The production of bosons is studied in proton-lead ($\Pp\text{Pb}$) collisions
at a nucleon-nucleon centre-of-mass energy of $\sqrtsNN=8.16\TeV$.
Measurements are performed in the $\Wpm\to\PGmpm\PGnGm$ channel using a data
sample corresponding to an integrated luminosity of $173.4\pm 6.1\nbinv$,
collected by the CMS Collaboration at the LHC. The number of positively and
negatively charged bosons is determined separately in the muon pseudorapidity
region in the laboratory frame $\abs{\eta_{\text{lab}}^{\PGm}}<2.4$ and
transverse momentum $\pt^{\PGm}>25\GeVc$. The boson differential cross
sections, muon charge asymmetry, and the ratios of boson yields for the
proton-going over the Pb-going beam directions are reported as a function of
the muon pseudorapidity in the nucleon-nucleon centre-of-mass frame. The
measurements are compared to the predictions from theoretical calculations
based on parton distribution functions (PDFs) at next-to-leading-order. The
results favour PDF calculations that include nuclear modifications and provide
constraints on the nuclear PDF global fits.

##  0.1 Introduction

The production of electroweak (EW) gauge bosons is considered to be a powerful
probe of the parton distribution functions (PDFs) of the proton [1]. Most
recent proton PDF sets include and boson production data from the Tevatron and
the CERN Large Hadron Collider (LHC) in their global fit analyses [2, 3, 4].
Similarly, the measurements of EW boson production in proton-nucleus and
nucleus-nucleus collisions, available for the first time at centre-of-mass
energies of the scale, provide constraints on nuclear modifications of the
PDFs [5, 6, 7, 8]. The presence of a nuclear environment modifies the parton
densities in the nucleus as compared to those in a free nucleon. The nuclear
PDFs (nPDFs) are expected to be enhanced for partons carrying a momentum
fraction in the range $5\times 10^{-2}\lesssim x\lesssim 10^{-1}$ in the so-
called antishadowing region, and suppressed for $x\lesssim 10^{-2}$ in the
shadowing region [9], with the modifications depending on the scale $Q^{2}$.
Because of the limited amount and type of experimental data sets available for
nuclear collisions, the determination of the nuclear parton densities is less
precise than for the free-proton case. As a consequence, the nPDF
uncertainties are one of the main limitations of the precision of quantum
chromodynamics (QCD) calculations describing hard-scattering processes in
nuclear collisions at high energies [7].

Since bosons are predominantly produced via annihilation through
$\cPqu\cPaqd\to\PWp$ and $\cPqd\cPaqu\to\PWm$ processes, boson production can
be used to probe the light quark PDFs, both for the proton and nuclei. In
addition, the asymmetries of the separate yields of and bosons are known to be
sensitive probes of the down-to-up quark PDF ratio [10, 11, 12]. Consequently,
their measurement may allow for the flavour decomposition of and quark
distributions in nuclei [13]. Among the possible decay channels of the boson,
the leptonic decays are less affected by background processes than hadronic
decays. Another advantage of the leptonic decays is that any possible effect
due to the QCD medium produced in nuclear collisions should be negligible,
since leptons are not subject to medium-induced energy loss through the strong
interaction [14, 15].

Studies of the and boson production in PbPb collisions at a nucleon-nucleon
centre-of-mass energy of $\sqrtsNN=2.76\TeV$, performed by the ATLAS [16, 17,
18] and CMS [19, 20, 21] Collaborations, have shown that the and boson cross
sections are consistent with no modification by the nuclear medium formed in
these collisions. In $\Pp\text{Pb}$ collisions, measurements of production at
$\sqrtsNN=5.02\TeV$ have been performed by ALICE [22] and CMS [13]. The
comparison with next-to-leading-order (NLO) perturbative QCD predictions
favours the calculations that include nPDF effects. A similar observation is
made from the analysis of the boson production in $\Pp\text{Pb}$ collisions at
the same energy [23, 24]. These EW boson measurements have been used for the
first time in a global fit analysis of nPDF sets (EPPS16 [25]). Nevertheless,
a modest enhancement of the boson production cross section in the most
backward region (Pb-going direction) showed some difference with theoretical
calculations (with and without nPDF effects), possibly pointing to different
nuclear modifications of the up and down quark PDFs [13]. More precise
measurements are thus needed in order to clarify the origin of this
discrepancy.

This letter reports the results of measurements of boson production in
$\Pp\text{Pb}$ collisions at $\sqrtsNN=8.16\TeV$. The measurements are
performed in the $\Wpm\to\PGmpm\PGnGm$ decay channel using $\Pp\text{Pb}$ data
recorded with the CMS detector in 2016, corresponding to a total integrated
luminosity of $173.4\pm 6.1\nbinv$. This data set is roughly five times larger
than the one available for the previous measurement at $\sqrtsNN=5.02\TeV$
[13, 26, 27]. The boson differential cross sections are presented as functions
of the muon pseudorapidity in the nucleon-nucleon centre-of-mass (CM) frame,
$\eta_{\text{CM}}$. In order to fully exploit the information provided by the
data, two additional sets of observables are also measured as functions of
$\eta_{\text{CM}}$: the muon charge asymmetry and the muon forward-backward
ratios ($R_{\mathrm{FB}}$). The measurement of asymmetries has a couple of
advantages as compared to that of the cross sections. First, asymmetries are
more sensitive to modifications of the quark PDFs [7]. Second, uncertainties
in the integrated luminosity and the theoretical scale dependence cancel in
the measurement of these asymmetries. The results of the boson differential
cross sections and asymmetries are compared to perturbative QCD calculations
based on NLO PDFs with and without nuclear modifications. The theoretical
predictions for free protons are obtained using the CT14 [2] proton PDF set,
while those including nuclear effects are derived using two different nPDF
sets for lead ions: nCTEQ15 [28] and EPPS16 [25].

##  0.2 Experimental methods

###  0.2.1 Data-taking conditions and the CMS detector

During the data-taking period, the directions of the proton and lead beams
were swapped after an integrated luminosity of 62.6was collected. The beam
energies were 6.5for the protons and 2.56per nucleon for the lead nuclei. By
convention, the proton-(Pb-)going side defines the positive (negative) $\eta$
region, labelled as the forward (backward) direction. Because of the
asymmetric collision system, massless particles produced in the nucleon-
nucleon centre-of-mass frame at an $\eta_{\text{CM}}$ are reconstructed at
$\eta_{\text{lab}}=\eta_{\text{CM}}+0.465$ in the laboratory frame. The boson
measurements presented in this letter are expressed in terms of the muon
pseudorapidity in the CM, $\eta_{\text{CM}}^{\PGm}$.

The central feature of the CMS apparatus is a superconducting solenoid of 6m
internal diameter, that provides a magnetic field of 3.8T. Within the solenoid
volume are a silicon pixel and strip tracker, a lead tungstate crystal
electromagnetic calorimeter (ECAL), and a brass and scintillator hadron
calorimeter (HCAL), each composed of a barrel and two endcap sections. Forward
calorimeters extend the $\eta$ coverage provided by the barrel and endcap
detectors. The hadron forward (HF) calorimeter uses steel as an absorber and
quartz fibres as the sensitive material. The two halves of the HF are located
11.2m from the interaction region, one on each end, and together they provide
coverage in the range $3.0<\abs{\eta}<5.2$. They also serve as luminosity
monitors. Muons are measured in the range $\abs{\eta}<2.4$, with detection
planes made using three technologies: drift tubes, cathode strip chambers, and
resistive plate chambers. A more detailed description of the CMS detector,
together with a definition of the coordinate system used and the relevant
kinematic variables, can be found in Ref. [29].

The particle-flow (PF) algorithm [30] aims to reconstruct and identify each
individual particle in an event, with an optimised combination of information
from the various elements of the CMS detector. The energy of photons is
obtained from the ECAL measurement. The energy of electrons is determined from
a combination of the electron momentum at the primary interaction vertex as
determined by the tracker, the energy of the corresponding ECAL cluster, and
the energy sum of all bremsstrahlung photons spatially compatible with
originating from the electron track. The charge and momentum of muons is
obtained from the curvature of the corresponding track. The energy of charged
hadrons is determined from a combination of their momentum measured in the
tracker (assuming the charged-pion mass) and the matching ECAL and HCAL energy
deposits, corrected for zero-suppression effects and for the response function
of the calorimeters to hadronic showers. Finally, the energy of neutral
hadrons is obtained from the corresponding corrected ECAL and HCAL energies.

###  0.2.2 Event selection and muon reconstruction

Collision events are required to have at least one interaction vertex
reconstructed using two or more tracks within a distance from the nominal
collision point of 25along the beam axis and 2along its transverse plane. The
contamination from background events not originating from inelastic hadronic
collisions is further suppressed by requiring at least one tower on each side
of the HF calorimeter with a total energy larger than 3. The loss of events
with bosons candidates due to this $\Pp\text{Pb}$ collision event selection
has been determined to be less than 0.2%.

The main signature of the $\Wpm\to\PGmpm\PGnGm$ process is the presence of an
isolated high-muon. Events of interest for offline analysis are selected using
a trigger algorithm [31] that requires the presence of at least one muon
candidate of $\pt>12\GeVc$. Moreover, to enhance the signal purity [13, 11],
the fiducial region of the analysis has been restricted to muons of
$\pt>25\GeVc$ with $\abs{\eta_{\text{lab}}^{\PGm}}<2.4$. The muon candidates
are reconstructed in CMS with an algorithm that combines the information from
the muon detectors and the tracker [32]. Muons are selected by applying the
standard tight selection criteria described in Ref. [32]. Further, muons are
required to be isolated from nearby hadronic activity to reduce the jet
background. The muon isolation parameter ($I_{\PGm}$) is defined as the sum of
all PF-reconstructed photons, charged and neutral hadrons, in a cone of radius
$R=\sqrt{\smash[b]{(\Delta\eta)^{2}+(\Delta\phi)^{2}}}=0.3$ around the muon
candidate, where $\Delta\eta$ and $\Delta\phi$ are the pseudorapidity and
azimuthal (in radians) distances to the muon. A muon is considered isolated if
$I_{\PGm}$ is less than 15% of the muon .

Background processes yielding high-muons can be classified as reducible or
irreducible. The reducible background includes muon decays that can be tagged
and removed from the signal. These events are mainly composed of pairs from
Drell–Yan events ($\PZ/\Pgg^{*}$), and high-muons from jets produced via the
strong interaction, referred to as QCD multijet events. To further suppress
the former processes, events containing at least two isolated oppositely
charged muons, each with $\pt^{\PGm}>15\GeVc$, are removed. The irreducible
background sources comprise muon decays that pass the analysis selection
criteria and therefore cannot be tagged event-by-event, including
$\PZ/\Pgg^{*}\to\TT$, $\PW\to\PGt\PGnGt$, and production. All backgrounds are
estimated using Monte Carlo (MC) simulations, except QCD multijet, which is
modelled with a data-driven technique described below.

###  0.2.3 Signal yield determination

Leptonic decays of bosons include neutrinos, which are not detected in CMS.
Their presence is inferred from the overall momentum imbalance in the
transverse plane, known as the missing transverse momentum ; its magnitude ()
is defined as the magnitude of the sum of the negative vectors of all
reconstructed PF objects in an event. In this analysis, the distribution is
used to extract the signal yields in 24 muon $\eta_{\text{CM}}^{\PGm}$ bins,
each 0.2 units wide, except for four in the most backward
($-2.86<\eta_{\text{CM}}^{\PGm}<-2.60$, $-2.20<\eta_{\text{CM}}^{\PGm}<-1.93$,
$-1.93<\eta_{\text{CM}}^{\PGm}<-1.80$), and forward
($1.80<\eta_{\text{CM}}^{\PGm}<1.93$) regions, because of the detector
geometry and the unbalanced beam energies.

The distributions of the signal and EW backgrounds are described using
templates from MC simulations. The MC samples were generated using the NLO
generator v2 [33, 34, 35]. To include EW corrections, the powhegbox packages
W_ew-BMNNP [36] and Z_ew-BMNNPV [37] are used to generate the
$\Pp\Pp\to\Wpm\to\Pl^{\pm}\PGnl$ and $\Pp\Pp\to\PZ/\Pgg^{*}\to\Pl^{+}\Pl^{-}$
processes, respectively. Events from the $\Pp\Pp\to\ttbar$ process are
generated using the powhegbox package hvq [38], which is a heavy flavour quark
generator. The simulation of $\Pp\text{Pb}$ collisions is performed using the
CT14 [2] PDF set corrected with the EPPS16 nuclear modification factors,
defined as the ratios of the bound proton PDF to that of a free proton,
derived for Pb ions [25]. The parton densities of protons and neutrons are
scaled according to the mass and atomic number of the lead isotopes.

The parton showering is performed by hadronising the events using 8.212 [39]
with the CUETP8M1 underlying-event (UE) tune [40, 41]. To consider a more
realistic distribution of the underlying environment present in $\Pp\text{Pb}$
collisions, the samples are embedded in simulated $\Pp\text{Pb}$ events
generated by epos lhc (v3400) [42], taking into account the $\Pp\text{Pb}$
boost. The epos lhc simulation is tuned to reproduce the global event
properties of the $\Pp\text{Pb}$ data such as the $\eta$ distributions of
charged hadrons [43]. The embedding of the signal and $\Pp\text{Pb}$ UEs is
performed by requiring the same generated interaction point when simulating
the detector hits. The trigger decisions are emulated and the embedded events
are reconstructed with the same algorithms as used for data. The detector
response is simulated with [44].

The agreement between the EW simulations and the data is improved by weighting
the EW boson distribution using a -dependent function derived from the ratio
of the boson distributions in $\PZ\to\MM$ events in data and simulation.
Furthermore, the $\Pp\text{Pb}$ event activity is reweighed by matching the
simulated total energy distribution reconstructed on both sides of the HF
calorimeters to the one observed in data in a $\PZ/\Pgg^{*}\to\MM$ sample.

The shape of the QCD multijet background is modelled with a functional form
described by a modified Rayleigh distribution [45] defined as:

$f\left(\ptmiss\right)=\ptmiss\exp\left[\left.-\left(\ptmiss\right)^{2}\right/2\left(\sigma_{0}+\sigma_{1}\ptmiss+\sigma_{2}\left(\ptmiss\right)^{2}\right)^{2}\right],$

where $\sigma_{0}$, $\sigma_{1}$, and $\sigma_{2}$ are free parameters to be
determined. It is found to reproduce well the shape of data events containing
nonisolated muons, with $\chi^{2}$ values divided by the number of degrees of
freedom (dof) close to one. The QCD shape is extracted by fitting the data in
five relative muon isolation ($I_{\PGm}$/$\pt^{\PGm}$) bins with boundaries
ranging from 0.4 to 0.9. The $\sigma_{0}$, $\sigma_{1}$, and $\sigma_{2}$
parameters extracted from the fits are found to linearly depend on the
relative muon isolation and are extrapolated to the isolated muon signal
region.

Because of momentum conservation, the production of and bosons is balanced by
a hadronic recoil composed of jets and particles from the $\Pp\text{Pb}$
underlying activity. The distribution of the hadronic recoil significantly
contributes to the resolution. Because of the similarity of the production
processes of the and bosons, and their similar masses, we assume that the
recoil distributions are the same for both species. Therefore, the correction
of the simulated recoil distribution is derived in a control region of
$\PZ\to\MM$ events using a hadronic recoil technique [46, 47]. The hadronic
recoil of $\PZ\to\MM$ events, ${\vec{u}}_{\mathrm{T}}$, is defined as the
vector sum of all PF candidates, excluding the decay products of the boson.
The distributions of the hadronic recoil components that are parallel and
perpendicular to the boson transverse momentum $\ptvec^{\PZ}$ are fitted in
simulation and data using a weighted sum of two Gaussian functions. The mean
and resolution values extracted from the recoil fits are used to scale the
simulated hadronic recoil distributions to match the performance measured in
data. The corrected distribution is then derived in the EW MC samples as the
vector sum of the corrected hadronic recoil
${\vec{u}}_{\mathrm{T}}^{\text{corr}}$ and the of the reconstructed muons from
the decay of and bosons.

The number of $\Wpm\to\PGmpm\PGnGm$ events is extracted by performing an
unbinned maximum likelihood fit of the observed distribution in each muon
$\eta_{\text{CM}}$ bin. The total fit model includes six contributions: the
signal $\Wpm\to\PGmpm\PGnGm$ template, the EW background $\PZ/\Pgg^{*}\to\MM$,
$\PW\to\PGt\PGnGt$ and $\PZ/\Pgg^{*}\to\TT$ templates, the background
template, and the QCD background functional form derived from control data
samples. When fitting the data, the QCD shape parameters ($\sigma_{i}$) are
fixed to the extrapolated values, while the ratio of the EW and background
yields to the signal yield is fixed to the results from simulation. Only two
parameters are left free in the fit, the boson signal and QCD background
normalisations. The observed numbers of muons coming from boson decays over
the entire $\eta_{\text{CM}}^{\PGm}$ range are: $97\,971\pm 332$ and
$81\,147\pm 301$ , where the uncertainty is statistical. Examples of the
resulting distributions in the midrapidity
($-0.2<\eta_{\text{CM}}^{\PGm}<0.0$) and forward
($1.80<\eta_{\text{CM}}^{\PGm}<1.93$) bins, are shown in Fig. 1, after
applying all analysis corrections and selection criteria. The fit model is
found to give a good description of the data, with $\chi^{2}$/dof values close
to one.

Figure 1: The missing transverse momentum distribution for
$\PWm\to\PGmm\PAGnGm$ events within the $-0.2<\eta_{\text{CM}}^{\PGm}<0.0$
(left) range and for $\PWp\to\PGmp\PGnGm$ events within the
$1.80<\eta_{\text{CM}}^{\PGm}<1.93$ (right) range. Unbinned fits to the data
(black points) are performed with six contributions, stacked from bottom to
top: (orange), $\PZ/\Pgg^{*}\to\TT$ (dark blue), $\Wpm\to\PGt^{\pm}\PGnGt$
(red), $\PZ/\Pgg^{*}\to\MM$ (green), QCD multijet (light blue) and
$\Wpm\to\PGmpm\PGnGm$ (yellow). The $\eta_{\text{CM}}^{\PGm}$ regions are
defined such that the proton is moving towards positive pseudorapidity. Error
bars represent statistical uncertainties. The lower panels display the data
divided by the result of the fit.

The simulated sample of $\Wpm\to\PGmpm\PGnGm$ embedded into epos lhc is used
to derive the efficiency of the muon trigger, isolation, reconstruction, and
selection criteria, as a function of $\eta_{\text{CM}}^{\PGm}$. These single-
muon efficiencies are also directly estimated from $\Pp\text{Pb}$ data in a
$\PZ\to\MM$ sample using the tag-and-probe (TnP) technique, as described in
Ref. [48]. The data and MC reconstruction efficiencies are observed to be
consistent with each other, whereas the trigger efficiency is lower in the
boson simulation by 5% than in data at $\abs{\eta_{\text{lab}}^{\PGm}}=1.4$.
The muon isolation selection is found to reject fewer muons in the simulation,
because of the smaller $\Pp\text{Pb}$ UE activity compared to data. In order
to correct for the differences between data and simulation, the muon
efficiency computed from the $\Wpm\to\PGmpm\PGnGm$ MC sample is multiplied by
the TnP correction factors event-by-event. These correction factors are
computed, in bins of muon and $\eta_{\text{lab}}$, from the ratio of the muon
efficiencies measured in data to those calculated from simulations. The TnP
scale factors produce changes in the muon efficiency ranging from $-3\%$ in
the mid-rapidity region ($\abs{\eta_{\text{lab}}^{\PGm}}<1.0$) to $+5\%$ at
$\abs{\eta_{\text{lab}}^{\PGm}}=1.4$. The TnP-corrected efficiencies vary with
$\eta_{\text{CM}}^{\PGm}$, from $(81\pm 1)\%$ to $(92\pm 2)\%$.

###  0.2.4 Systematic uncertainties

The leading source of systematic uncertainty originates from the TnP
efficiency corrections. The uncertainties on the TnP corrections are
determined by propagating the uncertainties on the muon efficiencies extracted
from data and simulation, derived from the fits to the invariant mass of
$\PZ\to\MM$ candidates. These uncertainties include a statistical component
due to the finite size of the data sample available, as well as a systematic
component estimated from variations in the fitting procedure (different signal
and background functions, and different mass range used for fitting).
Additionally, uncertainties are included to account for: (1) possible
differences in the reconstruction of muon tracks (0.6%), and (2) the impact of
pileup and UE activity (0.3%). Another important source of systematic
uncertainty arises from the modelling of the QCD multijet distribution in the
signal region, which is estimated by allowing the QCD shape parameters to vary
within the root-mean-square of the extrapolated values in bins of
$\eta_{\text{CM}}^{\PGm}$, and by changing the model to that used in Ref.
[13].

The uncertainty in the normalisation of the EW background is estimated from
the nPDF uncertainty in the over boson inclusive cross sections using the CT14
proton PDF and the EPPS16 nPDF for the lead ions, the uncertainty in the and
boson branching fractions to leptons [49], and the experimental uncertainty in
the cross section in $\Pp\text{Pb}$ events [50]. The uncertainty in the vector
boson reweighing is derived from the difference of the results obtained
applying and not applying the boson correction. The uncertainty in the binning
of the MC templates is estimated by using a bin size of 1. The impact of EW
corrections in is estimated from the difference in the efficiency when
computed using without EW corrections [51]. The uncertainty in the recoil
correction is determined by changing the model used to fit the hadronic recoil
distribution and the profile of the recoil mean and resolution as a function
of $\pt^{\PZ}$. Finally, the mismodelling of the UE activity in the simulation
is estimated by reweighing the distribution of the track multiplicity instead
of the energy deposited in the HF calorimeters. The integrated luminosity
measurement uncertainty (3.5%) [27] only affects the boson differential cross
sections and cancels out in the asymmetry measurements. The maximum relative
uncertainty of the differential cross sections and absolute uncertainties on
the asymmetries are presented for each source of systematic uncertainty in
Table 0.2.4.

Maximum uncertainty in the measured observables among the
$\eta_{\text{CM}}^{\PGm}$ bins determined for each source. The uncertainties
in the cross sections are relative, whereas those for the asymmetries are
absolute. The global integrated luminosity uncertainty of $\pm$3.5% is not
included in the total systematic uncertainty in the cross sections.  Source
σ$\eta_{\text{CM}}$ [%] σ$\eta_{\text{CM}}$ [%] $R_{\mathrm{FB}}$
$R_{\mathrm{FB}}$ $R_{\mathrm{FB}}$
$\frac{N_{\mu}^{+}-N_{\mu}^{-}}{N_{\mu}^{+}+N_{\mu}^{-}}$ Boson reweighing 0.5
0.4 0.001 0.001 0.001 0.001 EW background 0.4 0.3 0.002 0.001 0.001 0.000
POWHEG EW correction 0.9 0.5 0.007 0.004 0.006 0.003 Efficiency 3.0 3.2 0.026
0.037 0.030 0.011 Event activity reweighing 0.6 0.4 0.002 0.002 0.001 0.002
template binning 0.1 0.1 0.002 0.001 0.001 0.001 QCD background 1.2 0.7 0.016
0.007 0.009 0.006 Hadronic recoil correction 0.2 0.3 0.002 0.004 0.002 0.002
Total systematic uncertainty 3.3 3.3 0.030 0.038 0.031 0.013 Statistical
uncertainty 2.4 2.0 0.026 0.029 0.019 0.015

##  0.3 Results

The boson differential production cross sections are computed as functions of
$\eta_{\text{CM}}^{\PGm}$. The differential $\Wpm\to\PGmpm\PGnGm$ cross
sections are determined from

$\dd{\sigma^{\Wpm\to\PGmpm\PGnGm}}{\eta_{\text{CM}}^{\PGm}}\left(\eta_{\text{CM}}^{\PGm}\right)=\frac{N_{\PGm}\left(\eta_{\text{CM}}^{\PGm}\right)}{\Lumi\Delta\eta_{\text{CM}}^{\PGm}},$
(1)

where $N_{\PGm}\left(\eta_{\text{CM}}^{\PGm}\right)$ is the efficiency-
corrected muon yield in bins of $\eta_{\text{CM}}^{\PGm}$, is the recorded
integrated luminosity, and $\Delta\eta_{\text{CM}}^{\PGm}$ is the width of the
measured bin.

The cross sections for the $\PW\to\PGm\PGnGm$ decays for and bosons are
compared in Fig. 2 with NLO perturbative QCD predictions calculated with the
MC program v8.0 [52] using the CT14 [2] proton PDF. Also shown are two
calculations that include nuclear modifications in the PDF, based on the
nCTEQ15 [28] and EPPS16 [25] nPDF sets (labelled as CT14+nCTEQ15 and
CT14+EPPS16, respectively). Both EPPS16 and nCTEQ15 are Hessian NLO nPDF sets,
but the former includes more measurements in the fit (containing LHC EW boson
[13, 23, 24] and dijet [53] data), as well as more free parameters (20 for
EPPS16, 17 for nCTEQ15). In addition, nuclear modifications of valence and sea
quarks are allowed to be different in EPPS16 for up and down quarks, while
nCTEQ15 assumes flavour independence for the sea quarks. The nPDF
uncertainties are propagated using the PDF4LHC recommendations for Hessian
nPDF sets as prescribed in Ref. [1]. As can be seen in Fig. 2, the predicted
CT14+nCTEQ15 and CT14+EPPS16 cross sections are systematically below the
calculation using CT14 PDF at large positive muon rapidities because of the
depletion of the antiquark PDF in nuclei at small
$x=(M_{\PW}/\sqrtsNN)\exp(-y_{\PW})\simeq(M_{\PW}/\sqrtsNN)\exp(-\eta_{\text{CM}}^{\PGm})\approx
10^{-3}$. Conversely, the predicted cross sections from calculations including
nPDF modifications are above those using CT14 PDF in the negative rapidity
region, because of the slight quark antishadowing at large $x\approx 0.1$.
When compared to data, all theoretical calculations reproduce the measurement
at backward rapidity within uncertainties, while at forward rapidity the
calculations including nPDF effects appear to be favoured.

Figure 2: Differential production cross sections for $\PWp\to\PGmp\PGnGm$
(left) and $\PWm\to\PGmm\PAGnGm$ (right), as a function of the muon
pseudorapidity in the centre-of-mass frame. The small horizontal lines
represent the statistical and systematic uncertainties summed in quadrature,
whereas the error bars show the statistical uncertainties only. The global
integrated luminosity uncertainty of $\pm$3.5% is not shown. The NLO
calculations with CT14 PDF, and CT14+EPPS16 and CT14+nCTEQ15 nPDFs, are also
displayed, including their 68% confidence interval PDF uncertainty bands. The
bottom panels show the ratio of data, CT14+EPPS16 and CT14+nCTEQ15 with
respect to CT14.

The muon forward-backward ratios, defined as
$N_{\PGm}^{\pm}(+\eta_{\text{CM}}^{\PGm})/N_{\PGm}^{\pm}(-\eta_{\text{CM}}^{\PGm})$
for both positive and negative muons, are compared in the upper panel of Fig.
3 to the CT14 PDF, and CT14+EPPS16 and CT14+nCTEQ15 nPDF calculations. These
observables probe the ratio of the nuclear modifications of the quark PDFs in
the Pb nucleus from small to large $x$ values. The results for muons of both
charges favour the predictions including nuclear modifications over the free-
proton PDF calculations. Based on the precision of the experimental results,
the measurements provide constraints on both the CT14+EPPS16 and CT14+nCTEQ15
nPDF sets, especially in the proton-going region (small $x$).

Figure 3: Forward-backward ratios,
$N_{\PGm}^{\pm}(+\eta_{\text{CM}}^{\PGm})/N_{\PGm}^{\pm}(-\eta_{\text{CM}}^{\PGm})$,
for the positively (left) and negatively (middle) charged muons, and the
forward-backward ratio for muons of both signs,
$N_{\PGm}(+\eta_{\text{CM}}^{\PGm})/N_{\PGm}(-\eta_{\text{CM}}^{\PGm})$
(right), as a function of $\eta_{\text{CM}}^{\PGm}$. The small horizontal
lines represent the statistical and systematic uncertainties summed in
quadrature, whereas the error bars show the statistical uncertainties only.
The NLO calculations with CT14 PDF, CT14+EPPS16 nPDF, and CT14+nCTEQ15 nPDF,
are also displayed, including their 68% confidence interval PDF uncertainty
bands.

The yields of positively and negatively charged muons are further combined to
measure the forward-backward ratio for all muons
$N_{\PGm}(+\eta_{\text{CM}}^{\PGm})/N_{\PGm}(-\eta_{\text{CM}}^{\PGm})$. This
observable has a couple of advantages compared to
$N_{\PGm}^{\pm}(+\eta_{\text{CM}}^{\PGm})/N_{\PGm}^{\pm}(-\eta_{\text{CM}}^{\PGm})$:
it is less sensitive to the quark content in the proton and nuclei, and it has
better statistical precision. The results for this asymmetry are presented in
the right panel of Fig. 3, and they strongly deviate from the CT14 PDF
predictions, favouring the CT14+nCTEQ15 and CT14+EPPS16 nPDF sets. Moreover,
the experimental uncertainties are significantly smaller than the theoretical
nPDF uncertainties. Consequently, these measurements could constrain the quark
and antiquark distributions in nuclei, and will be valuable inputs for global
fits to the data.

The muon charge asymmetry, defined as
$\mathcal{A}\equiv(N_{\PGm}^{+}-N_{\PGm}^{-})/(N_{\PGm}^{+}+N_{\PGm}^{-})$,
reflects the differences in the production of and bosons. Figure 4 shows the
measurement of the muon charge asymmetry as a function of
$\eta_{\text{CM}}^{\PGm}$ compared to the [52] predictions calculated using
CT14 PDF alone and including nuclear modifications described by the EPPS16 and
nCTEQ15 nPDFs. All calculations reproduce the present measurements within
uncertainties in the entire muon $\eta$ range, including when the CT14 proton
PDF set is used, because nuclear modifications of the PDFs mostly cancel in
this quantity.

The tension between data and theoretical calculations reported at negative
muon $\eta$ in $\Pp\text{Pb}$ collisions at $\sqrtsNN=5.02\TeV$ [13] is not
observed in the present measurements. The present use of the CT14 proton PDF
set decreases the value of the charge asymmetry compared to the predictions
based on CT10 in Ref. [13]. Moreover, the theoretical uncertainties are also
enlarged in the EPPS16 nPDF sets and the theoretical calculations using the
CT14+EPPS16 nPDF sets agree better with the measurements at
$\sqrtsNN=5.02\TeV$, as compared to the EPS09 nPDF sets used in the analysis
at $\sqrtsNN=5.02\TeV$. It has been shown in Ref. [54] that the measurements
of the lepton charge asymmetry at different collision energies
($\sqrt{s^{\prime}}$) are simply related by a shift in the lepton
pseudorapidity,
$\mathcal{A}(\eta_{\Pl},\sqrt{s^{\prime}})=\mathcal{A}(\eta_{\text{ref}},\sqrt{s})$,
where $\eta_{\text{ref}}=\eta_{\Pl}+\ln(\sqrt{s}/\sqrt{s^{\prime}})$ if
$\eta_{\Pl}>0$ and
$\eta_{\text{ref}}=\eta_{\Pl}-\ln(\sqrt{s}/\sqrt{s^{\prime}})$ if
$\eta_{\Pl}<0$. The result of this shift is shown in Fig. 5, demonstrating
that the present results and the measurements performed at $\sqrtsNN=5.02\TeV$
[13] obey this scaling property.

Figure 4: Muon charge asymmetry,
$(N_{\PGm}^{+}-N_{\PGm}^{-})/(N_{\PGm}^{+}+N_{\PGm}^{-})$, as a function of
the muon pseudorapidity in the centre-of-mass frame. The small horizontal
lines represent the statistical and systematic uncertainties summed in
quadrature, whereas the error bars show the statistical uncertainties only.
The NLO calculations with CT14 PDF, CT14+EPPS16 nPDF, and CT14+nCTEQ15 nPDF,
are also displayed, including their 68% confidence interval PDF uncertainty
bands. Figure 5: Comparison of the muon charge asymmetry measured at
$\sqrtsNN=8.16\TeV$ (circles) and at $\sqrtsNN=5.02\TeV$ [13] (squares). The
muon pseudorapidity of the measurements at 5.02has been shifted (see text for
details) [54]. The small horizontal lines represent the statistical and
systematic uncertainties summed in quadrature, whereas the error bars show the
statistical uncertainties only. The NLO calculations with CT14+EPPS16 nPDF at
8.16and at 5.02, are also displayed, including their 68% confidence interval
PDF uncertainty bands.

The agreement between data and theoretical calculations is quantified through
a $\chi^{2}$ test performed for each observable taking into account both
experimental (including luminosity) and theoretical uncertainties and their
bin-to-bin correlations, obtained following the prescription for Hessian PDF
sets [55] and rescaled to 68% confidence intervals. The results of the
$\chi^{2}$ test and the dof of each observable are shown in Table 0.3. The
CT14+EPPS16 and CT14+nCTEQ15 nPDF predictions prove compatible with the data,
while the CT14 PDF calculations do not describe the measurements well. These
experimental results thus provide for the first time clear evidence of the
nuclear modification of quark PDFs from the measurements of EW boson
production in nuclear collisions. Bin-to-bin correlations have been found to
have a large impact on the obtained $\chi^{2}$ values, especially from nPDF
uncertainties in the NLO calculations, which are strongly correlated inside
each of the shadowing (positive $\eta_{\text{CM}}^{\PGm}$) and antishadowing
(negative $\eta_{\text{CM}}^{\PGm}$) regions, and anticorrelated between these
two regions.

Results of the $\chi^{2}$ statistical test between the measurements and the
nPDF calculations from the CT14 PDF, CT14+EPPS16 nPDF, and CT14+nCTEQ15 nPDF
sets. The value of the $\chi^{2}$, the number of degrees of freedom (dof) and
the $\chi^{2}$ probability (Prob.), are presented for the boson differential
cross sections, the muon charge asymmetries, the charged muon forward-backward
ratios, and the forward-backward ratios of all muons, respectively.
Observable CT14 CT14+EPPS16 CT14+nCTEQ15 $\chi^{2}$ dof Prob. [%] $\chi^{2}$
dof Prob. [%] $\chi^{2}$ dof Prob. [%]
σ^$\Wpm\to\PGmpm\PGnGm$($\eta_{\text{CM}}^{\PGm}$)$\eta_{\text{CM}}^{\PGm}$
135 48 3-8 32 48 96 40 48 79
$(N_{\PGm}^{+}-N_{\PGm}^{-})/(N_{\PGm}^{+}+N_{\PGm}^{-})$ 23 24 54 18 24 80 29
24 23
$N_{\PGm}^{\pm}(+\eta_{\text{CM}}^{\PGm})/N_{\PGm}^{\pm}(-\eta_{\text{CM}}^{\PGm})$
98 20 3-10 11 20 95 14 20 83
$N_{\PGm}(+\eta_{\text{CM}}^{\PGm})/N_{\PGm}(-\eta_{\text{CM}}^{\PGm})$ 87 10
2-12 3 10 99 5 10 90

Furthermore, the possible sources of differences between data and the (n)PDFs
are investigated. In the Hessian representation, a central PDF is given along
with error sets, each of which corresponds to an eigenvector of the covariance
matrix in parameter space [56]. The values of $\chi^{2}$/dof corresponding to
the compatibility between the cross section measurements and the calculations
using each of the individual sets of CT14, nCTEQ15, and EPPS16 (57, 33 and 41
error sets, respectively) have been determined. Figure 6 shows the
distribution of the $\chi^{2}$/dof values for the central and error sets. The
$\chi^{2}$/dof values obtained are for individual sets, thus ignoring
theoretical uncertainties and their correlations. While most of the EPPS16
individual sets lead to a good agreement with data (with $\chi^{2}$/dof around
unity), only those nCTEQ15 sets that exhibit the smaller quark shadowing at
small $x$ are more compatible with the data, yet with
$\chi^{2}/\text{dof}\gtrsim 2$. All CT14 PDF sets lead to a narrow
distribution centred around $\chi^{2}/\text{dof}\simeq 3$, because of the
strong constraints imposed by the large experimental data sets used to extract
them. The current measurements of boson production in $\Pp\text{Pb}$
collisions will permit further constraints on the quark and antiquark nPDFs
and the amount of quark shadowing in the nuclei.

Figure 6: Distribution of the $\chi^{2}$/dof values from the comparison of
data (cross section measurements) and theoretical calculations, for the CT14,
nCTEQ15, and EPPS16 individual error sets. The vertical dashed lines represent
the prediction corresponding to the central set of CT14, nCTEQ15, and EPPS16.

##  0.4 Summary

A study of boson production in $\Pp\text{Pb}$ collisions at a nucleon-nucleon
centre-of-mass energy of $\sqrtsNN=8.16\TeV$ is reported, using the muon decay
channel for muons with transverse momenta greater than 25and for absolute
values of the pseudorapidity in the laboratory frame
$\abs{\eta_{\text{lab}}^{\PGm}}<2.4$. The differential production cross
sections for positively and negatively charged $\PW\to\PGm\PGnGm$ decays, the
muon charge asymmetry, and the muon forward-backward ratios, are measured as
functions of the muon pseudorapidity in the centre-of-mass frame, in the range
$-2.86<\eta_{\text{CM}}^{\PGm}<1.93$.

The measurements are compared to theoretical predictions from both proton
parton distribution functions (PDFs) (CT14) and nuclear PDF (CT14+EPPS16 ,
CT14+nCTEQ15) sets. The cross sections and the forward-backward asymmetries
exhibit significant deviations from the CT14 prediction, revealing nuclear
modifications of the PDFs unambiguously for the first time in the production
of electroweak bosons in nuclear collisions. Both the CT14+EPPS16, and the
CT14+nCTEQ15 calculations show a good overall agreement with the data, with
the measurements favouring the former nPDF set. In the latter case, only the
individual sets that exhibit the smallest nuclear PDF modifications at small
values of $x$ (in the shadowing region) turn out to be compatible with
experimental measurements. The small experimental uncertainties allow for a
significant reduction in the current uncertainties on the quark and antiquark
nuclear PDFs in the range $10^{-3}\lesssim x\lesssim 10^{-1}$.

###### Acknowledgements.

We congratulate our colleagues in the CERN accelerator departments for the
excellent performance of the LHC and thank the technical and administrative
staffs at CERN and at other CMS institutes for their contributions to the
success of the CMS effort. In addition, we gratefully acknowledge the
computing centres and personnel of the Worldwide LHC Computing Grid for
delivering so effectively the computing infrastructure essential to our
analyses. Finally, we acknowledge the enduring support for the construction
and operation of the LHC and the CMS detector provided by the following
funding agencies: BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq,
CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST,
and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF
(Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, PUT and ERDF (Estonia); Academy
of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG,
and HGF (Germany); GSRT (Greece); NKFIA (Hungary); DAE and DST (India); IPM
(Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES
(Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT,
LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC
(Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom,
RAS, RFBR, and NRC KI (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI, and FEDER
(Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST
(Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK
(Turkey); NASU and SFFR (Ukraine); STFC (United Kingdom); DOE and NSF (USA).
Individuals have received support from the Marie-Curie programme and the
European Research Council and Horizon 2020 Grant, contract Nos. 675440 and
765710 (European Union); the Leventis Foundation; the A.P. Sloan Foundation;
the Alexander von Humboldt Foundation; the Belgian Federal Science Policy
Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dans
l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en
Technologie (IWT-Belgium); the F.R.S.-FNRS and FWO (Belgium) under the
“Excellence of Science – EOS” – be.h project n. 30820817; the Beijing
Municipal Science & Technology Commission, No. Z181100004218003; the Ministry
of Education, Youth and Sports (MEYS) of the Czech Republic; the Lendület
(“Momentum”) Programme and the János Bolyai Research Scholarship of the
Hungarian Academy of Sciences, the New National Excellence Program ÚNKP, the
NKFIA research grants 123842, 123959, 124845, 124850, 125105, 128713, 128786,
and 129058 (Hungary); the Council of Science and Industrial Research, India;
the HOMING PLUS programme of the Foundation for Polish Science, cofinanced
from European Union, Regional Development Fund, the Mobility Plus programme of
the Ministry of Science and Higher Education, the National Science Center
(Poland), contracts Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543,
2014/15/B/ST2/03998, and 2015/19/B/ST2/02861, Sonata-bis 2012/07/E/ST2/01406;
the National Priorities Research Program by Qatar National Research Fund; the
Programa Estatal de Fomento de la Investigación Científica y Técnica de
Excelencia María de Maeztu, grant MDM-2015-0509 and the Programa Severo Ochoa
del Principado de Asturias; the Thalis and Aristeia programmes cofinanced by
EU-ESF and the Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral
Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its
2nd Century Project Advancement Project (Thailand); the Welch Foundation,
contract C-1845; and the Weston Havens Foundation (USA).

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##  .5 The CMS Collaboration

Yerevan Physics Institute, Yerevan, Armenia
A.M. Sirunyan, A. Tumasyan Institut für Hochenergiephysik, Wien, Austria
W. Adam, F. Ambrogi, E. Asilar, T. Bergauer, J. Brandstetter, M. Dragicevic,
J. Erö, A. Escalante Del Valle, M. Flechl, R. Frühwirth1, V.M. Ghete, J.
Hrubec, M. Jeitler1, N. Krammer, I. Krätschmer, D. Liko, T. Madlener, I.
Mikulec, N. Rad, H. Rohringer, J. Schieck1, R. Schöfbeck, M. Spanring, D.
Spitzbart, A. Taurok, W. Waltenberger, J. Wittmann, C.-E. Wulz1, M. Zarucki
Institute for Nuclear Problems, Minsk, Belarus
V. Chekhovsky, V. Mossolov, J. Suarez Gonzalez Universiteit Antwerpen,
Antwerpen, Belgium
E.A. De Wolf, D. Di Croce, X. Janssen, J. Lauwers, M. Pieters, H. Van
Haevermaet, P. Van Mechelen, N. Van Remortel Vrije Universiteit Brussel,
Brussel, Belgium
S. Abu Zeid, F. Blekman, J. D’Hondt, I. De Bruyn, J. De Clercq, K. Deroover,
G. Flouris, D. Lontkovskyi, S. Lowette, I. Marchesini, S. Moortgat, L.
Moreels, Q. Python, K. Skovpen, S. Tavernier, W. Van Doninck, P. Van Mulders,
I. Van Parijs Université Libre de Bruxelles, Bruxelles, Belgium
D. Beghin, B. Bilin, H. Brun, B. Clerbaux, G. De Lentdecker, H. Delannoy, B.
Dorney, G. Fasanella, L. Favart, R. Goldouzian, A. Grebenyuk, A.K. Kalsi, T.
Lenzi, J. Luetic, N. Postiau, E. Starling, L. Thomas, C. Vander Velde, P.
Vanlaer, D. Vannerom, Q. Wang Ghent University, Ghent, Belgium
T. Cornelis, D. Dobur, A. Fagot, M. Gul, I. Khvastunov2, D. Poyraz, C. Roskas,
D. Trocino, M. Tytgat, W. Verbeke, B. Vermassen, M. Vit, N. Zaganidis
Université Catholique de Louvain, Louvain-la-Neuve, Belgium
H. Bakhshiansohi, O. Bondu, S. Brochet, G. Bruno, C. Caputo, P. David, C.
Delaere, M. Delcourt, A. Giammanco, G. Krintiras, V. Lemaitre, A. Magitteri,
A. Mertens, M. Musich, K. Piotrzkowski, A. Saggio, M. Vidal Marono, S. Wertz,
J. Zobec Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil
F.L. Alves, G.A. Alves, M. Correa Martins Junior, G. Correia Silva, C. Hensel,
A. Moraes, M.E. Pol, P. Rebello Teles Universidade do Estado do Rio de
Janeiro, Rio de Janeiro, Brazil
E. Belchior Batista Das Chagas, W. Carvalho, J. Chinellato3, E. Coelho, E.M.
Da Costa, G.G. Da Silveira4, D. De Jesus Damiao, C. De Oliveira Martins, S.
Fonseca De Souza, H. Malbouisson, D. Matos Figueiredo, M. Melo De Almeida, C.
Mora Herrera, L. Mundim, H. Nogima, W.L. Prado Da Silva, L.J. Sanchez Rosas,
A. Santoro, A. Sznajder, M. Thiel, E.J. Tonelli Manganote3, F. Torres Da Silva
De Araujo, A. Vilela Pereira Universidade Estadual Paulista a, Universidade
Federal do ABC b, São Paulo, Brazil
S. Ahujaa, C.A. Bernardesa, L. Calligarisa, T.R. Fernandez Perez Tomeia, E.M.
Gregoresb, P.G. Mercadanteb, S.F. Novaesa, SandraS. Padulaa Institute for
Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia,
Bulgaria
A. Aleksandrov, R. Hadjiiska, P. Iaydjiev, A. Marinov, M. Misheva, M. Rodozov,
M. Shopova, G. Sultanov University of Sofia, Sofia, Bulgaria
A. Dimitrov, L. Litov, B. Pavlov, P. Petkov Beihang University, Beijing, China
W. Fang5, X. Gao5, L. Yuan Institute of High Energy Physics, Beijing, China
M. Ahmad, J.G. Bian, G.M. Chen, H.S. Chen, M. Chen, Y. Chen, C.H. Jiang, D.
Leggat, H. Liao, Z. Liu, F. Romeo, S.M. Shaheen6, A. Spiezia, J. Tao, Z. Wang,
E. Yazgan, H. Zhang, S. Zhang6, J. Zhao State Key Laboratory of Nuclear
Physics and Technology, Peking University, Beijing, China
Y. Ban, G. Chen, A. Levin, J. Li, L. Li, Q. Li, Y. Mao, S.J. Qian, D. Wang, Z.
Xu Tsinghua University, Beijing, China
Y. Wang Universidad de Los Andes, Bogota, Colombia
C. Avila, A. Cabrera, C.A. Carrillo Montoya, L.F. Chaparro Sierra, C. Florez,
C.F. González Hernández, M.A. Segura Delgado University of Split, Faculty of
Electrical Engineering, Mechanical Engineering and Naval Architecture, Split,
Croatia
B. Courbon, N. Godinovic, D. Lelas, I. Puljak, T. Sculac University of Split,
Faculty of Science, Split, Croatia
Z. Antunovic, M. Kovac Institute Rudjer Boskovic, Zagreb, Croatia
V. Brigljevic, D. Ferencek, K. Kadija, B. Mesic, A. Starodumov7, T. Susa
University of Cyprus, Nicosia, Cyprus
M.W. Ather, A. Attikis, M. Kolosova, G. Mavromanolakis, J. Mousa, C. Nicolaou,
F. Ptochos, P.A. Razis, H. Rykaczewski Charles University, Prague, Czech
Republic
M. Finger8, M. Finger Jr.8 Escuela Politecnica Nacional, Quito, Ecuador
E. Ayala Universidad San Francisco de Quito, Quito, Ecuador
E. Carrera Jarrin Academy of Scientific Research and Technology of the Arab
Republic of Egypt, Egyptian Network of High Energy Physics, Cairo, Egypt
A. Ellithi Kamel9, M.A. Mahmoud10,11, Y. Mohammed10 National Institute of
Chemical Physics and Biophysics, Tallinn, Estonia
S. Bhowmik, A. Carvalho Antunes De Oliveira, R.K. Dewanjee, K. Ehataht, M.
Kadastik, M. Raidal, C. Veelken Department of Physics, University of Helsinki,
Helsinki, Finland
P. Eerola, H. Kirschenmann, J. Pekkanen, M. Voutilainen Helsinki Institute of
Physics, Helsinki, Finland
J. Havukainen, J.K. Heikkilä, T. Järvinen, V. Karimäki, R. Kinnunen, T.
Lampén, K. Lassila-Perini, S. Laurila, S. Lehti, T. Lindén, P. Luukka, T.
Mäenpää, H. Siikonen, E. Tuominen, J. Tuominiemi Lappeenranta University of
Technology, Lappeenranta, Finland
T. Tuuva IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
M. Besancon, F. Couderc, M. Dejardin, D. Denegri, J.L. Faure, F. Ferri, S.
Ganjour, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, C. Leloup,
E. Locci, J. Malcles, G. Negro, J. Rander, A. Rosowsky, M.Ö. Sahin, M. Titov
Laboratoire Leprince-Ringuet, CNRS/IN2P3, Ecole Polytechnique, Institut
Polytechnique de Paris
A. Abdulsalam12, C. Amendola, I. Antropov, F. Arleo, F. Beaudette, P. Busson,
C. Charlot, R. Granier de Cassagnac, I. Kucher, A. Lobanov, J. Martin Blanco,
C. Martin Perez, M. Nguyen, C. Ochando, G. Ortona, P. Paganini, P. Pigard, J.
Rembser, R. Salerno, J.B. Sauvan, Y. Sirois, A.G. Stahl Leiton, A. Zabi, A.
Zghiche Université de Strasbourg, CNRS, IPHC UMR 7178, Strasbourg, France
J.-L. Agram13, J. Andrea, D. Bloch, J.-M. Brom, E.C. Chabert, V. Cherepanov,
C. Collard, E. Conte13, J.-C. Fontaine13, D. Gelé, U. Goerlach, M. Jansová,
A.-C. Le Bihan, N. Tonon, P. Van Hove Centre de Calcul de l’Institut National
de Physique Nucleaire et de Physique des Particules, CNRS/IN2P3, Villeurbanne,
France
S. Gadrat Université de Lyon, Université Claude Bernard Lyon 1, CNRS-IN2P3,
Institut de Physique Nucléaire de Lyon, Villeurbanne, France
S. Beauceron, C. Bernet, G. Boudoul, N. Chanon, R. Chierici, D. Contardo, P.
Depasse, H. El Mamouni, J. Fay, L. Finco, S. Gascon, M. Gouzevitch, G.
Grenier, B. Ille, F. Lagarde, I.B. Laktineh, H. Lattaud, M. Lethuillier, L.
Mirabito, S. Perries, A. Popov14, V. Sordini, G. Touquet, M. Vander Donckt, S.
Viret Georgian Technical University, Tbilisi, Georgia
A. Khvedelidze8 Tbilisi State University, Tbilisi, Georgia
Z. Tsamalaidze8 RWTH Aachen University, I. Physikalisches Institut, Aachen,
Germany
C. Autermann, L. Feld, M.K. Kiesel, K. Klein, M. Lipinski, M. Preuten, M.P.
Rauch, C. Schomakers, J. Schulz, M. Teroerde, B. Wittmer, V. Zhukov14 RWTH
Aachen University, III. Physikalisches Institut A, Aachen, Germany
A. Albert, D. Duchardt, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, S. Ghosh,
A. Güth, T. Hebbeker, C. Heidemann, K. Hoepfner, H. Keller, L. Mastrolorenzo,
M. Merschmeyer, A. Meyer, P. Millet, S. Mukherjee, T. Pook, M. Radziej, H.
Reithler, M. Rieger, A. Schmidt, D. Teyssier, S. Thüer RWTH Aachen University,
III. Physikalisches Institut B, Aachen, Germany
G. Flügge, O. Hlushchenko, T. Kress, A. Künsken, T. Müller, A. Nehrkorn, A.
Nowack, C. Pistone, O. Pooth, D. Roy, H. Sert, A. Stahl15 Deutsches
Elektronen-Synchrotron, Hamburg, Germany
M. Aldaya Martin, T. Arndt, C. Asawatangtrakuldee, I. Babounikau, K.
Beernaert, O. Behnke, U. Behrens, A. Bermúdez Martínez, D. Bertsche, A.A. Bin
Anuar, K. Borras16, V. Botta, A. Campbell, P. Connor, C. Contreras-Campana, V.
Danilov, A. De Wit, M.M. Defranchis, C. Diez Pardos, D. Domínguez Damiani, G.
Eckerlin, T. Eichhorn, A. Elwood, E. Eren, E. Gallo17, A. Geiser, A.
Grohsjean, M. Guthoff, M. Haranko, A. Harb, J. Hauk, H. Jung, M. Kasemann, J.
Keaveney, C. Kleinwort, J. Knolle, D. Krücker, W. Lange, A. Lelek, T. Lenz, J.
Leonard, K. Lipka, W. Lohmann18, R. Mankel, I.-A. Melzer-Pellmann, A.B. Meyer,
M. Meyer, M. Missiroli, G. Mittag, J. Mnich, V. Myronenko, S.K. Pflitsch, D.
Pitzl, A. Raspereza, M. Savitskyi, P. Saxena, P. Schütze, C. Schwanenberger,
R. Shevchenko, A. Singh, H. Tholen, O. Turkot, A. Vagnerini, G.P. Van Onsem,
R. Walsh, Y. Wen, K. Wichmann, C. Wissing, O. Zenaiev University of Hamburg,
Hamburg, Germany
R. Aggleton, S. Bein, L. Benato, A. Benecke, V. Blobel, T. Dreyer, A.
Ebrahimi, E. Garutti, D. Gonzalez, P. Gunnellini, J. Haller, A. Hinzmann, A.
Karavdina, G. Kasieczka, R. Klanner, R. Kogler, N. Kovalchuk, S. Kurz, V.
Kutzner, J. Lange, D. Marconi, J. Multhaup, M. Niedziela, C.E.N. Niemeyer, D.
Nowatschin, A. Perieanu, A. Reimers, O. Rieger, C. Scharf, P. Schleper, S.
Schumann, J. Schwandt, J. Sonneveld, H. Stadie, G. Steinbrück, F.M. Stober, M.
Stöver, A. Vanhoefer, B. Vormwald, I. Zoi Karlsruher Institut fuer
Technologie, Karlsruhe, Germany
M. Akbiyik, C. Barth, M. Baselga, S. Baur, E. Butz, R. Caspart, T. Chwalek, F.
Colombo, W. De Boer, A. Dierlamm, K. El Morabit, N. Faltermann, B. Freund, M.
Giffels, M.A. Harrendorf, F. Hartmann15, S.M. Heindl, U. Husemann, F.
Kassel15, I. Katkov14, S. Kudella, S. Mitra, M.U. Mozer, Th. Müller, M.
Plagge, G. Quast, K. Rabbertz, M. Schröder, I. Shvetsov, G. Sieber, H.J.
Simonis, R. Ulrich, S. Wayand, M. Weber, T. Weiler, S. Williamson, C.
Wöhrmann, R. Wolf Institute of Nuclear and Particle Physics (INPP), NCSR
Demokritos, Aghia Paraskevi, Greece
G. Anagnostou, G. Daskalakis, T. Geralis, A. Kyriakis, D. Loukas, G.
Paspalaki, I. Topsis-Giotis National and Kapodistrian University of Athens,
Athens, Greece
B. Francois, G. Karathanasis, S. Kesisoglou, P. Kontaxakis, A. Panagiotou, I.
Papavergou, N. Saoulidou, E. Tziaferi, K. Vellidis National Technical
University of Athens, Athens, Greece
K. Kousouris, I. Papakrivopoulos, G. Tsipolitis University of Ioánnina,
Ioánnina, Greece
I. Evangelou, C. Foudas, P. Gianneios, P. Katsoulis, P. Kokkas, S. Mallios, N.
Manthos, I. Papadopoulos, E. Paradas, J. Strologas, F.A. Triantis, D.
Tsitsonis MTA-ELTE Lendület CMS Particle and Nuclear Physics Group, Eötvös
Loránd University, Budapest, Hungary
M. Bartók19, M. Csanad, N. Filipovic, P. Major, M.I. Nagy, G. Pasztor, O.
Surányi, G.I. Veres Wigner Research Centre for Physics, Budapest, Hungary
G. Bencze, C. Hajdu, D. Horvath20, Á. Hunyadi, F. Sikler, T.Á. Vámi, V.
Veszpremi, G. Vesztergombi${}^{\textrm{\textdagger}}$ Institute of Nuclear
Research ATOMKI, Debrecen, Hungary
N. Beni, S. Czellar, J. Karancsi21, A. Makovec, J. Molnar, Z. Szillasi
Institute of Physics, University of Debrecen, Debrecen, Hungary
P. Raics, Z.L. Trocsanyi, B. Ujvari Indian Institute of Science (IISc),
Bangalore, India
S. Choudhury, J.R. Komaragiri, P.C. Tiwari National Institute of Science
Education and Research, HBNI, Bhubaneswar, India
S. Bahinipati22, C. Kar, P. Mal, K. Mandal, A. Nayak23, D.K. Sahoo22, S.K.
Swain Panjab University, Chandigarh, India
S. Bansal, S.B. Beri, V. Bhatnagar, S. Chauhan, R. Chawla, N. Dhingra, R.
Gupta, A. Kaur, M. Kaur, S. Kaur, R. Kumar, P. Kumari, M. Lohan, A. Mehta, K.
Sandeep, S. Sharma, J.B. Singh, A.K. Virdi, G. Walia University of Delhi,
Delhi, India
A. Bhardwaj, B.C. Choudhary, R.B. Garg, M. Gola, S. Keshri, Ashok Kumar, S.
Malhotra, M. Naimuddin, P. Priyanka, K. Ranjan, Aashaq Shah, R. Sharma Saha
Institute of Nuclear Physics, HBNI, Kolkata, India
R. Bhardwaj24, M. Bharti24, R. Bhattacharya, S. Bhattacharya, U. Bhawandeep24,
D. Bhowmik, S. Dey, S. Dutt24, S. Dutta, S. Ghosh, K. Mondal, S. Nandan, A.
Purohit, P.K. Rout, A. Roy, S. Roy Chowdhury, G. Saha, S. Sarkar, M. Sharan,
B. Singh24, S. Thakur24 Indian Institute of Technology Madras, Madras, India
P.K. Behera Bhabha Atomic Research Centre, Mumbai, India
R. Chudasama, D. Dutta, V. Jha, V. Kumar, P.K. Netrakanti, L.M. Pant, P.
Shukla Tata Institute of Fundamental Research-A, Mumbai, India
T. Aziz, M.A. Bhat, S. Dugad, G.B. Mohanty, N. Sur, B. Sutar, RavindraKumar
Verma Tata Institute of Fundamental Research-B, Mumbai, India
S. Banerjee, S. Bhattacharya, S. Chatterjee, P. Das, M. Guchait, Sa. Jain, S.
Karmakar, S. Kumar, M. Maity25, G. Majumder, K. Mazumdar, N. Sahoo, T.
Sarkar25 Indian Institute of Science Education and Research (IISER), Pune,
India
S. Chauhan, S. Dube, V. Hegde, A. Kapoor, K. Kothekar, S. Pandey, A. Rane, S.
Sharma Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
S. Chenarani26, E. Eskandari Tadavani, S.M. Etesami26, M. Khakzad, M.
Mohammadi Najafabadi, M. Naseri, F. Rezaei Hosseinabadi, B. Safarzadeh27, M.
Zeinali University College Dublin, Dublin, Ireland
M. Felcini, M. Grunewald INFN Sezione di Bari a, Università di Bari b,
Politecnico di Bari c, Bari, Italy
M. Abbresciaa,b, C. Calabriaa,b, A. Colaleoa, D. Creanzaa,c, L. Cristellaa,b,
N. De Filippisa,c, M. De Palmaa,b, A. Di Florioa,b, F. Erricoa,b, L. Fiorea,
A. Gelmia,b, G. Iasellia,c, M. Incea,b, S. Lezkia,b, G. Maggia,c, M. Maggia,
G. Minielloa,b, S. Mya,b, S. Nuzzoa,b, A. Pompilia,b, G. Pugliesea,c, R.
Radognaa, A. Ranieria, G. Selvaggia,b, A. Sharmaa, L. Silvestrisa, R.
Vendittia, P. Verwilligena, G. Zitoa INFN Sezione di Bologna a, Università di
Bologna b, Bologna, Italy
G. Abbiendia, C. Battilanaa,b, D. Bonacorsia,b, L. Borgonovia,b, S. Braibant-
Giacomellia,b, R. Campaninia,b, P. Capiluppia,b, A. Castroa,b, F.R. Cavalloa,
S.S. Chhibraa,b, C. Cioccaa, G. Codispotia,b, M. Cuffiania,b, G.M.
Dallavallea, F. Fabbria, A. Fanfania,b, E. Fontanesi, P. Giacomellia, C.
Grandia, L. Guiduccia,b, F. Iemmia,b, S. Lo Meoa, S. Marcellinia, G. Masettia,
A. Montanaria, F.L. Navarriaa,b, A. Perrottaa, F. Primaveraa,b,15, T.
Rovellia,b, G.P. Sirolia,b, N. Tosia INFN Sezione di Catania a, Università di
Catania b, Catania, Italy
S. Albergoa,b, A. Di Mattiaa, R. Potenzaa,b, A. Tricomia,b, C. Tuvea,b INFN
Sezione di Firenze a, Università di Firenze b, Firenze, Italy
G. Barbaglia, K. Chatterjeea,b, V. Ciullia,b, C. Civininia, R.
D’Alessandroa,b, E. Focardia,b, G. Latino, P. Lenzia,b, M. Meschinia, S.
Paolettia, L. Russoa,28, G. Sguazzonia, D. Stroma, L. Viliania INFN Laboratori
Nazionali di Frascati, Frascati, Italy
L. Benussi, S. Bianco, F. Fabbri, D. Piccolo INFN Sezione di Genova a,
Università di Genova b, Genova, Italy
F. Ferroa, F. Raveraa,b, E. Robuttia, S. Tosia,b INFN Sezione di Milano-
Bicocca a, Università di Milano-Bicocca b, Milano, Italy
A. Benagliaa, A. Beschib, L. Brianzaa,b, F. Brivioa,b, V. Cirioloa,b,15, S. Di
Guidaa,d,15, M.E. Dinardoa,b, S. Fiorendia,b, S. Gennaia, A. Ghezzia,b, P.
Govonia,b, M. Malbertia,b, S. Malvezzia, A. Massironia,b, D. Menascea, F.
Monti, L. Moronia, M. Paganonia,b, D. Pedrinia, S. Ragazzia,b, T. Tabarelli de
Fatisa,b, D. Zuoloa,b INFN Sezione di Napoli a, Università di Napoli ’Federico
II’ b, Napoli, Italy, Università della Basilicata c, Potenza, Italy,
Università G. Marconi d, Roma, Italy
S. Buontempoa, N. Cavalloa,c, A. De Iorioa,b, A. Di Crescenzoa,b, F.
Fabozzia,c, F. Fiengaa, G. Galatia, A.O.M. Iorioa,b, W.A. Khana, L. Listaa, S.
Meolaa,d,15, P. Paoluccia,15, C. Sciaccaa,b, E. Voevodinaa,b INFN Sezione di
Padova a, Università di Padova b, Padova, Italy, Università di Trento c,
Trento, Italy
P. Azzia, N. Bacchettaa, D. Biselloa,b, A. Bolettia,b, A. Bragagnolo, R.
Carlina,b, P. Checchiaa, M. Dall’Ossoa,b, P. De Castro Manzanoa, T. Dorigoa,
U. Dossellia, F. Gasparinia,b, U. Gasparinia,b, A. Gozzelinoa, S.Y. Hoh, S.
Lacapraraa, P. Lujan, M. Margonia,b, A.T. Meneguzzoa,b, J. Pazzinia,b, P.
Ronchesea,b, R. Rossina,b, F. Simonettoa,b, A. Tiko, E. Torassaa, M.
Zanettia,b, P. Zottoa,b, G. Zumerlea,b INFN Sezione di Pavia a, Università di
Pavia b, Pavia, Italy
A. Braghieria, A. Magnania, P. Montagnaa,b, S.P. Rattia,b, V. Rea, M.
Ressegottia,b, C. Riccardia,b, P. Salvinia, I. Vaia,b, P. Vituloa,b INFN
Sezione di Perugia a, Università di Perugia b, Perugia, Italy
M. Biasinia,b, G.M. Bileia, C. Cecchia,b, D. Ciangottinia,b, L. Fanòa,b, P.
Laricciaa,b, R. Leonardia,b, E. Manonia, G. Mantovania,b, V. Mariania,b, M.
Menichellia, A. Rossia,b, A. Santocchiaa,b, D. Spigaa INFN Sezione di Pisa a,
Università di Pisa b, Scuola Normale Superiore di Pisa c, Pisa, Italy
K. Androsova, P. Azzurria, G. Bagliesia, L. Bianchinia, T. Boccalia, L.
Borrello, R. Castaldia, M.A. Cioccia,b, R. Dell’Orsoa, G. Fedia, F. Fioria,c,
L. Gianninia,c, A. Giassia, M.T. Grippoa, F. Ligabuea,c, E. Mancaa,c, G.
Mandorlia,c, A. Messineoa,b, F. Pallaa, A. Rizzia,b, P. Spagnoloa, R.
Tenchinia, G. Tonellia,b, A. Venturia, P.G. Verdinia INFN Sezione di Roma a,
Sapienza Università di Roma b, Rome, Italy
L. Baronea,b, F. Cavallaria, M. Cipriania,b, D. Del Rea,b, E. Di Marcoa,b, M.
Diemoza, S. Gellia,b, E. Longoa,b, B. Marzocchia,b, P. Meridiania, G.
Organtinia,b, F. Pandolfia, R. Paramattia,b, F. Preiatoa,b, S. Rahatloua,b, C.
Rovellia, F. Santanastasioa,b INFN Sezione di Torino a, Università di Torino
b, Torino, Italy, Università del Piemonte Orientale c, Novara, Italy
N. Amapanea,b, R. Arcidiaconoa,c, S. Argiroa,b, M. Arneodoa,c, N. Bartosika,
R. Bellana,b, C. Biinoa, N. Cartigliaa, F. Cennaa,b, S. Comettia, M. Costaa,b,
R. Covarellia,b, N. Demariaa, B. Kiania,b, C. Mariottia, S. Masellia, E.
Migliorea,b, V. Monacoa,b, E. Monteila,b, M. Montenoa, M.M. Obertinoa,b, L.
Pachera,b, N. Pastronea, M. Pelliccionia, G.L. Pinna Angionia,b, A. Romeroa,b,
M. Ruspaa,c, R. Sacchia,b, K. Shchelinaa,b, V. Solaa, A. Solanoa,b, D.
Soldia,b, A. Staianoa INFN Sezione di Trieste a, Università di Trieste b,
Trieste, Italy
S. Belfortea, V. Candelisea,b, M. Casarsaa, F. Cossuttia, A. Da Rolda,b, G.
Della Riccaa,b, F. Vazzolera,b, A. Zanettia Kyungpook National University,
Daegu, Korea
D.H. Kim, G.N. Kim, M.S. Kim, J. Lee, S. Lee, S.W. Lee, C.S. Moon, Y.D. Oh,
S.I. Pak, S. Sekmen, D.C. Son, Y.C. Yang Chonnam National University,
Institute for Universe and Elementary Particles, Kwangju, Korea
H. Kim, D.H. Moon, G. Oh Hanyang University, Seoul, Korea
J. Goh29, T.J. Kim Korea University, Seoul, Korea
S. Cho, S. Choi, Y. Go, D. Gyun, S. Ha, B. Hong, Y. Jo, K. Lee, K.S. Lee, S.
Lee, J. Lim, S.K. Park, Y. Roh Sejong University, Seoul, Korea
H.S. Kim Seoul National University, Seoul, Korea
J. Almond, J. Kim, J.S. Kim, H. Lee, K. Lee, K. Nam, S.B. Oh, B.C. Radburn-
Smith, S.h. Seo, U.K. Yang, H.D. Yoo, G.B. Yu University of Seoul, Seoul,
Korea
D. Jeon, H. Kim, J.H. Kim, J.S.H. Lee, I.C. Park Sungkyunkwan University,
Suwon, Korea
Y. Choi, C. Hwang, J. Lee, I. Yu Vilnius University, Vilnius, Lithuania
V. Dudenas, A. Juodagalvis, J. Vaitkus National Centre for Particle Physics,
Universiti Malaya, Kuala Lumpur, Malaysia
I. Ahmed, Z.A. Ibrahim, M.A.B. Md Ali30, F. Mohamad Idris31, W.A.T. Wan
Abdullah, M.N. Yusli, Z. Zolkapli Universidad de Sonora (UNISON), Hermosillo,
Mexico
J.F. Benitez, A. Castaneda Hernandez, J.A. Murillo Quijada Centro de
Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico
H. Castilla-Valdez, E. De La Cruz-Burelo, M.C. Duran-Osuna, I. Heredia-De La
Cruz32, R. Lopez-Fernandez, J. Mejia Guisao, R.I. Rabadan-Trejo, M. Ramirez-
Garcia, G. Ramirez-Sanchez, R Reyes-Almanza, A. Sanchez-Hernandez Universidad
Iberoamericana, Mexico City, Mexico
S. Carrillo Moreno, C. Oropeza Barrera, F. Vazquez Valencia Benemerita
Universidad Autonoma de Puebla, Puebla, Mexico
J. Eysermans, I. Pedraza, H.A. Salazar Ibarguen, C. Uribe Estrada Universidad
Autónoma de San Luis Potosí, San Luis Potosí, Mexico
A. Morelos Pineda University of Auckland, Auckland, New Zealand
D. Krofcheck University of Canterbury, Christchurch, New Zealand
S. Bheesette, P.H. Butler National Centre for Physics, Quaid-I-Azam
University, Islamabad, Pakistan
A. Ahmad, M. Ahmad, M.I. Asghar, Q. Hassan, H.R. Hoorani, A. Saddique, M.A.
Shah, M. Shoaib, M. Waqas National Centre for Nuclear Research, Swierk, Poland
H. Bialkowska, M. Bluj, B. Boimska, T. Frueboes, M. Górski, M. Kazana, M.
Szleper, P. Traczyk, P. Zalewski Institute of Experimental Physics, Faculty of
Physics, University of Warsaw, Warsaw, Poland
K. Bunkowski, A. Byszuk33, K. Doroba, A. Kalinowski, M. Konecki, J.
Krolikowski, M. Misiura, M. Olszewski, A. Pyskir, M. Walczak Laboratório de
Instrumentação e Física Experimental de Partículas, Lisboa, Portugal
M. Araujo, P. Bargassa, C. Beirão Da Cruz E Silva, A. Di Francesco, P.
Faccioli, B. Galinhas, M. Gallinaro, J. Hollar, N. Leonardo, M.V. Nemallapudi,
J. Seixas, G. Strong, O. Toldaiev, D. Vadruccio, J. Varela Joint Institute for
Nuclear Research, Dubna, Russia
S. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, I. Gorbunov, A. Kamenev,
V. Karjavine, A. Lanev, A. Malakhov, V. Matveev34,35, P. Moisenz, V. Palichik,
V. Perelygin, S. Shmatov, S. Shulha, N. Skatchkov, V. Smirnov, N. Voytishin,
A. Zarubin Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg),
Russia
V. Golovtsov, Y. Ivanov, V. Kim36, E. Kuznetsova37, P. Levchenko, V. Murzin,
V. Oreshkin, I. Smirnov, D. Sosnov, V. Sulimov, L. Uvarov, S. Vavilov, A.
Vorobyev Institute for Nuclear Research, Moscow, Russia
Yu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, A. Karneyeu, M. Kirsanov,
N. Krasnikov, A. Pashenkov, D. Tlisov, A. Toropin Institute for Theoretical
and Experimental Physics named by A.I. Alikhanov of NRC ‘Kurchatov Institute’,
Moscow, Russia
V. Epshteyn, V. Gavrilov, N. Lychkovskaya, V. Popov, I. Pozdnyakov, G.
Safronov, A. Spiridonov, A. Stepennov, V. Stolin, M. Toms, E. Vlasov, A.
Zhokin Moscow Institute of Physics and Technology, Moscow, Russia
T. Aushev National Research Nuclear University ’Moscow Engineering Physics
Institute’ (MEPhI), Moscow, Russia
M. Chadeeva38, P. Parygin, D. Philippov, S. Polikarpov38, E. Popova, V.
Rusinov P.N. Lebedev Physical Institute, Moscow, Russia
V. Andreev, M. Azarkin, I. Dremin35, M. Kirakosyan, S.V. Rusakov, A. Terkulov
Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University,
Moscow, Russia
A. Baskakov, A. Belyaev, E. Boos, A. Demiyanov, A. Ershov, A. Gribushin, O.
Kodolova, V. Korotkikh, I. Lokhtin, I. Miagkov, S. Obraztsov, S. Petrushanko,
V. Savrin, A. Snigirev, I. Vardanyan Novosibirsk State University (NSU),
Novosibirsk, Russia
A. Barnyakov39, V. Blinov39, T. Dimova39, L. Kardapoltsev39, Y. Skovpen39
Institute for High Energy Physics of National Research Centre ‘Kurchatov
Institute’, Protvino, Russia
I. Azhgirey, I. Bayshev, S. Bitioukov, D. Elumakhov, A. Godizov, V. Kachanov,
A. Kalinin, D. Konstantinov, P. Mandrik, V. Petrov, R. Ryutin, S.
Slabospitskii, A. Sobol, S. Troshin, N. Tyurin, A. Uzunian, A. Volkov National
Research Tomsk Polytechnic University, Tomsk, Russia
A. Babaev, S. Baidali, V. Okhotnikov University of Belgrade: Faculty of
Physics and VINCA Institute of Nuclear Sciences
P. Adzic40, P. Cirkovic, D. Devetak, M. Dordevic, J. Milosevic Centro de
Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid,
Spain
J. Alcaraz Maestre, A. Álvarez Fernández, I. Bachiller, M. Barrio Luna, J.A.
Brochero Cifuentes, M. Cerrada, N. Colino, B. De La Cruz, A. Delgado Peris, C.
Fernandez Bedoya, J.P. Fernández Ramos, J. Flix, M.C. Fouz, O. Gonzalez Lopez,
S. Goy Lopez, J.M. Hernandez, M.I. Josa, D. Moran, A. Pérez-Calero Yzquierdo,
J. Puerta Pelayo, I. Redondo, L. Romero, M.S. Soares, A. Triossi Universidad
Autónoma de Madrid, Madrid, Spain
C. Albajar, J.F. de Trocóniz Universidad de Oviedo, Instituto Universitario de
Ciencias y Tecnologías Espaciales de Asturias (ICTEA), Oviedo, Spain
J. Cuevas, C. Erice, J. Fernandez Menendez, S. Folgueras, I. Gonzalez
Caballero, J.R. González Fernández, E. Palencia Cortezon, V. Rodríguez Bouza,
S. Sanchez Cruz, P. Vischia, J.M. Vizan Garcia Instituto de Física de
Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, Spain
I.J. Cabrillo, A. Calderon, B. Chazin Quero, J. Duarte Campderros, M.
Fernandez, P.J. Fernández Manteca, A. García Alonso, J. Garcia-Ferrero, G.
Gomez, A. Lopez Virto, J. Marco, C. Martinez Rivero, P. Martinez Ruiz del
Arbol, F. Matorras, J. Piedra Gomez, C. Prieels, T. Rodrigo, A. Ruiz-Jimeno,
L. Scodellaro, N. Trevisani, I. Vila, R. Vilar Cortabitarte University of
Ruhuna, Department of Physics, Matara, Sri Lanka
N. Wickramage CERN, European Organization for Nuclear Research, Geneva,
Switzerland
D. Abbaneo, B. Akgun, E. Auffray, G. Auzinger, P. Baillon, A.H. Ball, D.
Barney, J. Bendavid, M. Bianco, A. Bocci, C. Botta, E. Brondolin, T.
Camporesi, M. Cepeda, G. Cerminara, E. Chapon, Y. Chen, G. Cucciati, D.
d’Enterria, A. Dabrowski, N. Daci, V. Daponte, A. David, A. De Roeck, N.
Deelen, M. Dobson, M. Dünser, N. Dupont, A. Elliott-Peisert, P. Everaerts, F.
Fallavollita41, D. Fasanella, G. Franzoni, J. Fulcher, W. Funk, D. Gigi, A.
Gilbert, K. Gill, F. Glege, M. Guilbaud, D. Gulhan, J. Hegeman, C. Heidegger,
V. Innocente, A. Jafari, P. Janot, O. Karacheban18, J. Kieseler, A. Kornmayer,
M. Krammer1, C. Lange, P. Lecoq, C. Lourenço, L. Malgeri, M. Mannelli, F.
Meijers, J.A. Merlin, S. Mersi, E. Meschi, P. Milenovic42, F. Moortgat, M.
Mulders, J. Ngadiuba, S. Nourbakhsh, S. Orfanelli, L. Orsini, F. Pantaleo15,
L. Pape, E. Perez, M. Peruzzi, A. Petrilli, G. Petrucciani, A. Pfeiffer, M.
Pierini, F.M. Pitters, D. Rabady, A. Racz, T. Reis, G. Rolandi43, M. Rovere,
H. Sakulin, C. Schäfer, C. Schwick, M. Seidel, M. Selvaggi, A. Sharma, P.
Silva, P. Sphicas44, A. Stakia, J. Steggemann, M. Tosi, D. Treille, A. Tsirou,
V. Veckalns45, M. Verzetti, W.D. Zeuner Paul Scherrer Institut, Villigen,
Switzerland
L. Caminada46, K. Deiters, W. Erdmann, R. Horisberger, Q. Ingram, H.C.
Kaestli, D. Kotlinski, U. Langenegger, T. Rohe, S.A. Wiederkehr ETH Zurich -
Institute for Particle Physics and Astrophysics (IPA), Zurich, Switzerland
M. Backhaus, L. Bäni, P. Berger, N. Chernyavskaya, G. Dissertori, M. Dittmar,
M. Donegà, C. Dorfer, T.A. Gómez Espinosa, C. Grab, D. Hits, T. Klijnsma, W.
Lustermann, R.A. Manzoni, M. Marionneau, M.T. Meinhard, F. Micheli, P.
Musella, F. Nessi-Tedaldi, J. Pata, F. Pauss, G. Perrin, L. Perrozzi, S.
Pigazzini, M. Quittnat, C. Reissel, D. Ruini, D.A. Sanz Becerra, M.
Schönenberger, L. Shchutska, V.R. Tavolaro, K. Theofilatos, M.L. Vesterbacka
Olsson, R. Wallny, D.H. Zhu Universität Zürich, Zurich, Switzerland
T.K. Aarrestad, C. Amsler47, D. Brzhechko, M.F. Canelli, A. De Cosa, R. Del
Burgo, S. Donato, C. Galloni, T. Hreus, B. Kilminster, S. Leontsinis, I.
Neutelings, G. Rauco, P. Robmann, D. Salerno, K. Schweiger, C. Seitz, Y.
Takahashi, A. Zucchetta National Central University, Chung-Li, Taiwan
Y.H. Chang, K.y. Cheng, T.H. Doan, R. Khurana, C.M. Kuo, W. Lin, A.
Pozdnyakov, S.S. Yu National Taiwan University (NTU), Taipei, Taiwan
P. Chang, Y. Chao, K.F. Chen, P.H. Chen, W.-S. Hou, Arun Kumar, Y.F. Liu,
R.-S. Lu, E. Paganis, A. Psallidas, A. Steen Chulalongkorn University, Faculty
of Science, Department of Physics, Bangkok, Thailand
B. Asavapibhop, N. Srimanobhas, N. Suwonjandee Çukurova University, Physics
Department, Science and Art Faculty, Adana, Turkey
A. Bat, F. Boran, S. Cerci48, S. Damarseckin, Z.S. Demiroglu, F. Dolek, C.
Dozen, I. Dumanoglu, S. Girgis, G. Gokbulut, Y. Guler, E. Gurpinar, I. Hos49,
C. Isik, E.E. Kangal50, O. Kara, A. Kayis Topaksu, U. Kiminsu, M. Oglakci, G.
Onengut, K. Ozdemir51, S. Ozturk52, D. Sunar Cerci48, B. Tali48, U.G. Tok, S.
Turkcapar, I.S. Zorbakir, C. Zorbilmez Middle East Technical University,
Physics Department, Ankara, Turkey
B. Isildak53, G. Karapinar54, M. Yalvac, M. Zeyrek Bogazici University,
Istanbul, Turkey
I.O. Atakisi, E. Gülmez, M. Kaya55, O. Kaya56, S. Ozkorucuklu57, S. Tekten,
E.A. Yetkin58 Istanbul Technical University, Istanbul, Turkey
M.N. Agaras, A. Cakir, K. Cankocak, Y. Komurcu, S. Sen59 Institute for
Scintillation Materials of National Academy of Science of Ukraine, Kharkov,
Ukraine
B. Grynyov National Scientific Center, Kharkov Institute of Physics and
Technology, Kharkov, Ukraine
L. Levchuk University of Bristol, Bristol, United Kingdom
F. Ball, L. Beck, J.J. Brooke, D. Burns, E. Clement, D. Cussans, O. Davignon,
H. Flacher, J. Goldstein, G.P. Heath, H.F. Heath, L. Kreczko, D.M. Newbold60,
S. Paramesvaran, B. Penning, T. Sakuma, D. Smith, V.J. Smith, J. Taylor, A.
Titterton Rutherford Appleton Laboratory, Didcot, United Kingdom
A. Belyaev61, C. Brew, R.M. Brown, D. Cieri, D.J.A. Cockerill, J.A. Coughlan,
K. Harder, S. Harper, J. Linacre, E. Olaiya, D. Petyt, C.H. Shepherd-
Themistocleous, A. Thea, I.R. Tomalin, T. Williams, W.J. Womersley Imperial
College, London, United Kingdom
R. Bainbridge, P. Bloch, J. Borg, S. Breeze, O. Buchmuller, A. Bundock, D.
Colling, P. Dauncey, G. Davies, M. Della Negra, R. Di Maria, Y. Haddad, G.
Hall, G. Iles, T. James, M. Komm, C. Laner, L. Lyons, A.-M. Magnan, S. Malik,
A. Martelli, J. Nash62, A. Nikitenko7, V. Palladino, M. Pesaresi, D.M.
Raymond, A. Richards, A. Rose, E. Scott, C. Seez, A. Shtipliyski, G. Singh, M.
Stoye, T. Strebler, S. Summers, A. Tapper, K. Uchida, T. Virdee15, N. Wardle,
D. Winterbottom, J. Wright, S.C. Zenz Brunel University, Uxbridge, United
Kingdom
J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, C.K. Mackay, A. Morton, I.D. Reid,
L. Teodorescu, S. Zahid Baylor University, Waco, USA
K. Call, J. Dittmann, K. Hatakeyama, H. Liu, C. Madrid, B. Mcmaster, N.
Pastika, C. Smith Catholic University of America, Washington, DC, USA
R. Bartek, A. Dominguez The University of Alabama, Tuscaloosa, USA
A. Buccilli, S.I. Cooper, C. Henderson, P. Rumerio, C. West Boston University,
Boston, USA
D. Arcaro, T. Bose, D. Gastler, D. Pinna, D. Rankin, C. Richardson, J. Rohlf,
L. Sulak, D. Zou Brown University, Providence, USA
G. Benelli, X. Coubez, D. Cutts, M. Hadley, J. Hakala, U. Heintz, J.M.
Hogan63, K.H.M. Kwok, E. Laird, G. Landsberg, J. Lee, Z. Mao, M. Narain, S.
Sagir64, R. Syarif, E. Usai, D. Yu University of California, Davis, Davis, USA
R. Band, C. Brainerd, R. Breedon, D. Burns, M. Calderon De La Barca Sanchez,
M. Chertok, J. Conway, R. Conway, P.T. Cox, R. Erbacher, C. Flores, G. Funk,
W. Ko, O. Kukral, R. Lander, M. Mulhearn, D. Pellett, J. Pilot, S. Shalhout,
M. Shi, D. Stolp, D. Taylor, K. Tos, M. Tripathi, Z. Wang, F. Zhang University
of California, Los Angeles, USA
M. Bachtis, C. Bravo, R. Cousins, A. Dasgupta, A. Florent, J. Hauser, M.
Ignatenko, N. Mccoll, S. Regnard, D. Saltzberg, C. Schnaible, V. Valuev
University of California, Riverside, Riverside, USA
E. Bouvier, K. Burt, R. Clare, J.W. Gary, S.M.A. Ghiasi Shirazi, G. Hanson, G.
Karapostoli, E. Kennedy, F. Lacroix, O.R. Long, M. Olmedo Negrete, M.I.
Paneva, W. Si, L. Wang, H. Wei, S. Wimpenny, B.R. Yates University of
California, San Diego, La Jolla, USA
J.G. Branson, P. Chang, S. Cittolin, M. Derdzinski, R. Gerosa, D. Gilbert, B.
Hashemi, A. Holzner, D. Klein, G. Kole, V. Krutelyov, J. Letts, M.
Masciovecchio, D. Olivito, S. Padhi, M. Pieri, M. Sani, V. Sharma, S. Simon,
M. Tadel, A. Vartak, S. Wasserbaech65, J. Wood, F. Würthwein, A. Yagil, G.
Zevi Della Porta University of California, Santa Barbara - Department of
Physics, Santa Barbara, USA
N. Amin, R. Bhandari, J. Bradmiller-Feld, C. Campagnari, M. Citron, A. Dishaw,
V. Dutta, M. Franco Sevilla, L. Gouskos, R. Heller, J. Incandela, A.
Ovcharova, H. Qu, J. Richman, D. Stuart, I. Suarez, S. Wang, J. Yoo California
Institute of Technology, Pasadena, USA
D. Anderson, A. Bornheim, J.M. Lawhorn, H.B. Newman, T.Q. Nguyen, M.
Spiropulu, J.R. Vlimant, R. Wilkinson, S. Xie, Z. Zhang, R.Y. Zhu Carnegie
Mellon University, Pittsburgh, USA
M.B. Andrews, T. Ferguson, T. Mudholkar, M. Paulini, M. Sun, I. Vorobiev, M.
Weinberg University of Colorado Boulder, Boulder, USA
J.P. Cumalat, W.T. Ford, F. Jensen, A. Johnson, M. Krohn, E. MacDonald, T.
Mulholland, R. Patel, A. Perloff, K. Stenson, K.A. Ulmer, S.R. Wagner Cornell
University, Ithaca, USA
J. Alexander, J. Chaves, Y. Cheng, J. Chu, A. Datta, K. Mcdermott, N. Mirman,
J.R. Patterson, D. Quach, A. Rinkevicius, A. Ryd, L. Skinnari, L. Soffi, S.M.
Tan, Z. Tao, J. Thom, J. Tucker, P. Wittich, M. Zientek Fermi National
Accelerator Laboratory, Batavia, USA
S. Abdullin, M. Albrow, M. Alyari, G. Apollinari, A. Apresyan, A. Apyan, S.
Banerjee, L.A.T. Bauerdick, A. Beretvas, J. Berryhill, P.C. Bhat, K. Burkett,
J.N. Butler, A. Canepa, G.B. Cerati, H.W.K. Cheung, F. Chlebana, M. Cremonesi,
J. Duarte, V.D. Elvira, J. Freeman, Z. Gecse, E. Gottschalk, L. Gray, D.
Green, S. Grünendahl, O. Gutsche, J. Hanlon, R.M. Harris, S. Hasegawa, J.
Hirschauer, Z. Hu, B. Jayatilaka, S. Jindariani, M. Johnson, U. Joshi, B.
Klima, M.J. Kortelainen, B. Kreis, S. Lammel, D. Lincoln, R. Lipton, M. Liu,
T. Liu, J. Lykken, K. Maeshima, J.M. Marraffino, D. Mason, P. McBride, P.
Merkel, S. Mrenna, S. Nahn, V. O’Dell, K. Pedro, C. Pena, O. Prokofyev, G.
Rakness, L. Ristori, A. Savoy-Navarro66, B. Schneider, E. Sexton-Kennedy, A.
Soha, W.J. Spalding, L. Spiegel, S. Stoynev, J. Strait, N. Strobbe, L. Taylor,
S. Tkaczyk, N.V. Tran, L. Uplegger, E.W. Vaandering, C. Vernieri, M.
Verzocchi, R. Vidal, M. Wang, H.A. Weber, A. Whitbeck University of Florida,
Gainesville, USA
D. Acosta, P. Avery, P. Bortignon, D. Bourilkov, A. Brinkerhoff, L. Cadamuro,
A. Carnes, M. Carver, D. Curry, R.D. Field, S.V. Gleyzer, B.M. Joshi, J.
Konigsberg, A. Korytov, K.H. Lo, P. Ma, K. Matchev, H. Mei, G. Mitselmakher,
D. Rosenzweig, K. Shi, D. Sperka, J. Wang, S. Wang, X. Zuo Florida
International University, Miami, USA
Y.R. Joshi, S. Linn Florida State University, Tallahassee, USA
A. Ackert, T. Adams, A. Askew, S. Hagopian, V. Hagopian, K.F. Johnson, T.
Kolberg, G. Martinez, T. Perry, H. Prosper, A. Saha, C. Schiber, R. Yohay
Florida Institute of Technology, Melbourne, USA
M.M. Baarmand, V. Bhopatkar, S. Colafranceschi, M. Hohlmann, D. Noonan, M.
Rahmani, T. Roy, F. Yumiceva University of Illinois at Chicago (UIC), Chicago,
USA
M.R. Adams, L. Apanasevich, D. Berry, R.R. Betts, R. Cavanaugh, X. Chen, S.
Dittmer, O. Evdokimov, C.E. Gerber, D.A. Hangal, D.J. Hofman, K. Jung, J.
Kamin, C. Mills, I.D. Sandoval Gonzalez, M.B. Tonjes, H. Trauger, N. Varelas,
H. Wang, X. Wang, Z. Wu, J. Zhang The University of Iowa, Iowa City, USA
M. Alhusseini, B. Bilki67, W. Clarida, K. Dilsiz68, S. Durgut, R.P.
Gandrajula, M. Haytmyradov, V. Khristenko, J.-P. Merlo, A. Mestvirishvili, A.
Moeller, J. Nachtman, H. Ogul69, Y. Onel, F. Ozok70, A. Penzo, C. Snyder, E.
Tiras, J. Wetzel Johns Hopkins University, Baltimore, USA
B. Blumenfeld, A. Cocoros, N. Eminizer, D. Fehling, L. Feng, A.V. Gritsan,
W.T. Hung, P. Maksimovic, J. Roskes, U. Sarica, M. Swartz, M. Xiao, C. You The
University of Kansas, Lawrence, USA
A. Al-bataineh, P. Baringer, A. Bean, S. Boren, J. Bowen, A. Bylinkin, J.
Castle, S. Khalil, A. Kropivnitskaya, D. Majumder, W. Mcbrayer, M. Murray, C.
Rogan, S. Sanders, E. Schmitz, J.D. Tapia Takaki, Q. Wang Kansas State
University, Manhattan, USA
S. Duric, A. Ivanov, K. Kaadze, D. Kim, Y. Maravin, D.R. Mendis, T. Mitchell,
A. Modak, A. Mohammadi, L.K. Saini, N. Skhirtladze Lawrence Livermore National
Laboratory, Livermore, USA
F. Rebassoo, D. Wright University of Maryland, College Park, USA
A. Baden, O. Baron, A. Belloni, S.C. Eno, Y. Feng, C. Ferraioli, N.J. Hadley,
S. Jabeen, G.Y. Jeng, R.G. Kellogg, J. Kunkle, A.C. Mignerey, S. Nabili, F.
Ricci-Tam, Y.H. Shin, A. Skuja, S.C. Tonwar, K. Wong Massachusetts Institute
of Technology, Cambridge, USA
D. Abercrombie, B. Allen, V. Azzolini, A. Baty, G. Bauer, R. Bi, S. Brandt, W.
Busza, I.A. Cali, M. D’Alfonso, Z. Demiragli, G. Gomez Ceballos, M. Goncharov,
P. Harris, D. Hsu, M. Hu, Y. Iiyama, G.M. Innocenti, M. Klute, D. Kovalskyi,
Y.-J. Lee, P.D. Luckey, B. Maier, A.C. Marini, C. Mcginn, C. Mironov, S.
Narayanan, X. Niu, C. Paus, C. Roland, G. Roland, G.S.F. Stephans, K. Sumorok,
K. Tatar, D. Velicanu, J. Wang, T.W. Wang, B. Wyslouch, S. Zhaozhong
University of Minnesota, Minneapolis, USA
A.C. Benvenuti${}^{\textrm{\textdagger}}$, R.M. Chatterjee, A. Evans, P.
Hansen, Sh. Jain, S. Kalafut, Y. Kubota, Z. Lesko, J. Mans, N. Ruckstuhl, R.
Rusack, J. Turkewitz, M.A. Wadud University of Mississippi, Oxford, USA
J.G. Acosta, S. Oliveros University of Nebraska-Lincoln, Lincoln, USA
E. Avdeeva, K. Bloom, D.R. Claes, C. Fangmeier, F. Golf, R. Gonzalez Suarez,
R. Kamalieddin, I. Kravchenko, J. Monroy, J.E. Siado, G.R. Snow, B. Stieger
State University of New York at Buffalo, Buffalo, USA
A. Godshalk, C. Harrington, I. Iashvili, A. Kharchilava, C. Mclean, D. Nguyen,
A. Parker, S. Rappoccio, B. Roozbahani Northeastern University, Boston, USA
G. Alverson, E. Barberis, C. Freer, A. Hortiangtham, D.M. Morse, T. Orimoto,
R. Teixeira De Lima, T. Wamorkar, B. Wang, A. Wisecarver, D. Wood Northwestern
University, Evanston, USA
S. Bhattacharya, O. Charaf, K.A. Hahn, N. Mucia, N. Odell, M.H. Schmitt, K.
Sung, M. Trovato, M. Velasco University of Notre Dame, Notre Dame, USA
R. Bucci, N. Dev, M. Hildreth, K. Hurtado Anampa, C. Jessop, D.J. Karmgard, N.
Kellams, K. Lannon, W. Li, N. Loukas, N. Marinelli, F. Meng, C. Mueller, Y.
Musienko34, M. Planer, A. Reinsvold, R. Ruchti, P. Siddireddy, G. Smith, S.
Taroni, M. Wayne, A. Wightman, M. Wolf, A. Woodard The Ohio State University,
Columbus, USA
J. Alimena, L. Antonelli, B. Bylsma, L.S. Durkin, S. Flowers, B. Francis, A.
Hart, C. Hill, W. Ji, T.Y. Ling, W. Luo, B.L. Winer Princeton University,
Princeton, USA
S. Cooperstein, P. Elmer, J. Hardenbrook, S. Higginbotham, A. Kalogeropoulos,
D. Lange, M.T. Lucchini, J. Luo, D. Marlow, K. Mei, I. Ojalvo, J. Olsen, C.
Palmer, P. Piroué, J. Salfeld-Nebgen, D. Stickland, C. Tully University of
Puerto Rico, Mayaguez, USA
S. Malik, S. Norberg Purdue University, West Lafayette, USA
A. Barker, V.E. Barnes, S. Das, L. Gutay, M. Jones, A.W. Jung, A. Khatiwada,
B. Mahakud, D.H. Miller, N. Neumeister, C.C. Peng, S. Piperov, H. Qiu, J.F.
Schulte, J. Sun, F. Wang, R. Xiao, W. Xie Purdue University Northwest,
Hammond, USA
T. Cheng, J. Dolen, N. Parashar Rice University, Houston, USA
Z. Chen, K.M. Ecklund, S. Freed, F.J.M. Geurts, M. Kilpatrick, W. Li, B.P.
Padley, R. Redjimi, J. Roberts, J. Rorie, W. Shi, Z. Tu, J. Zabel, A. Zhang
University of Rochester, Rochester, USA
A. Bodek, P. de Barbaro, R. Demina, Y.t. Duh, J.L. Dulemba, C. Fallon, T.
Ferbel, M. Galanti, A. Garcia-Bellido, J. Han, O. Hindrichs, A.
Khukhunaishvili, P. Tan, R. Taus Rutgers, The State University of New Jersey,
Piscataway, USA
A. Agapitos, J.P. Chou, Y. Gershtein, E. Halkiadakis, M. Heindl, E. Hughes, S.
Kaplan, R. Kunnawalkam Elayavalli, S. Kyriacou, A. Lath, R. Montalvo, K. Nash,
M. Osherson, H. Saka, S. Salur, S. Schnetzer, D. Sheffield, S. Somalwar, R.
Stone, S. Thomas, P. Thomassen, M. Walker University of Tennessee, Knoxville,
USA
A.G. Delannoy, J. Heideman, G. Riley, S. Spanier Texas A&M University, College
Station, USA
O. Bouhali71, A. Celik, M. Dalchenko, M. De Mattia, A. Delgado, S. Dildick, R.
Eusebi, J. Gilmore, T. Huang, T. Kamon72, S. Luo, R. Mueller, D. Overton, L.
Perniè, D. Rathjens, A. Safonov Texas Tech University, Lubbock, USA
N. Akchurin, J. Damgov, F. De Guio, P.R. Dudero, S. Kunori, K. Lamichhane,
S.W. Lee, T. Mengke, S. Muthumuni, T. Peltola, S. Undleeb, I. Volobouev, Z.
Wang Vanderbilt University, Nashville, USA
S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, A. Melo, H. Ni, K.
Padeken, J.D. Ruiz Alvarez, P. Sheldon, S. Tuo, J. Velkovska, M. Verweij, Q.
Xu University of Virginia, Charlottesville, USA
M.W. Arenton, P. Barria, B. Cox, R. Hirosky, M. Joyce, A. Ledovskoy, H. Li, C.
Neu, T. Sinthuprasith, Y. Wang, E. Wolfe, F. Xia Wayne State University,
Detroit, USA
R. Harr, P.E. Karchin, N. Poudyal, J. Sturdy, P. Thapa, S. Zaleski University
of Wisconsin - Madison, Madison, WI, USA
M. Brodski, J. Buchanan, C. Caillol, D. Carlsmith, S. Dasu, L. Dodd, B.
Gomber, M. Grothe, M. Herndon, A. Hervé, U. Hussain, P. Klabbers, A. Lanaro,
K. Long, R. Loveless, T. Ruggles, A. Savin, V. Sharma, N. Smith, W.H. Smith,
N. Woods †: Deceased
1: Also at Vienna University of Technology, Vienna, Austria
2: Also at IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
3: Also at Universidade Estadual de Campinas, Campinas, Brazil
4: Also at Federal University of Rio Grande do Sul, Porto Alegre, Brazil
5: Also at Université Libre de Bruxelles, Bruxelles, Belgium
6: Also at University of Chinese Academy of Sciences, Beijing, China
7: Also at Institute for Theoretical and Experimental Physics named by A.I.
Alikhanov of NRC ‘Kurchatov Institute’, Moscow, Russia
8: Also at Joint Institute for Nuclear Research, Dubna, Russia
9: Now at Cairo University, Cairo, Egypt
10: Also at Fayoum University, El-Fayoum, Egypt
11: Now at British University in Egypt, Cairo, Egypt
12: Also at Department of Physics, King Abdulaziz University, Jeddah, Saudi
Arabia
13: Also at Université de Haute Alsace, Mulhouse, France
14: Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State
University, Moscow, Russia
15: Also at CERN, European Organization for Nuclear Research, Geneva,
Switzerland
16: Also at RWTH Aachen University, III. Physikalisches Institut A, Aachen,
Germany
17: Also at University of Hamburg, Hamburg, Germany
18: Also at Brandenburg University of Technology, Cottbus, Germany
19: Also at MTA-ELTE Lendület CMS Particle and Nuclear Physics Group, Eötvös
Loránd University, Budapest, Hungary, Budapest, Hungary
20: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary
21: Also at Institute of Physics, University of Debrecen, Debrecen, Hungary,
Debrecen, Hungary
22: Also at IIT Bhubaneswar, Bhubaneswar, India, Bhubaneswar, India
23: Also at Institute of Physics, Bhubaneswar, India
24: Also at Shoolini University, Solan, India
25: Also at University of Visva-Bharati, Santiniketan, India
26: Also at Isfahan University of Technology, Isfahan, Iran
27: Also at Plasma Physics Research Center, Science and Research Branch,
Islamic Azad University, Tehran, Iran
28: Also at Università degli Studi di Siena, Siena, Italy
29: Also at Kyung Hee University, Department of Physics, Seoul, Korea
30: Also at International Islamic University of Malaysia, Kuala Lumpur,
Malaysia
31: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia
32: Also at Consejo Nacional de Ciencia y Tecnología, Mexico City, Mexico
33: Also at Warsaw University of Technology, Institute of Electronic Systems,
Warsaw, Poland
34: Also at Institute for Nuclear Research, Moscow, Russia
35: Now at National Research Nuclear University ’Moscow Engineering Physics
Institute’ (MEPhI), Moscow, Russia
36: Also at St. Petersburg State Polytechnical University, St. Petersburg,
Russia
37: Also at University of Florida, Gainesville, USA
38: Also at P.N. Lebedev Physical Institute, Moscow, Russia
39: Also at Budker Institute of Nuclear Physics, Novosibirsk, Russia
40: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia
41: Also at INFN Sezione di Pavia a, Università di Pavia b, Pavia, Italy,
Pavia, Italy
42: Also at University of Belgrade: Faculty of Physics and VINCA Institute of
Nuclear Sciences, Belgrade, Serbia
43: Also at Scuola Normale e Sezione dell’INFN, Pisa, Italy
44: Also at National and Kapodistrian University of Athens, Athens, Greece
45: Also at Riga Technical University, Riga, Latvia, Riga, Latvia
46: Also at Universität Zürich, Zurich, Switzerland
47: Also at Stefan Meyer Institute for Subatomic Physics, Vienna, Austria,
Vienna, Austria
48: Also at Adiyaman University, Adiyaman, Turkey
49: Also at Istanbul Aydin University, Istanbul, Turkey
50: Also at Mersin University, Mersin, Turkey
51: Also at Piri Reis University, Istanbul, Turkey
52: Also at Gaziosmanpasa University, Tokat, Turkey
53: Also at Ozyegin University, Istanbul, Turkey
54: Also at Izmir Institute of Technology, Izmir, Turkey
55: Also at Marmara University, Istanbul, Turkey
56: Also at Kafkas University, Kars, Turkey
57: Also at Istanbul University, Istanbul, Turkey
58: Also at Istanbul Bilgi University, Istanbul, Turkey
59: Also at Hacettepe University, Ankara, Turkey
60: Also at Rutherford Appleton Laboratory, Didcot, United Kingdom
61: Also at School of Physics and Astronomy, University of Southampton,
Southampton, United Kingdom
62: Also at Monash University, Faculty of Science, Clayton, Australia
63: Also at Bethel University, St. Paul, Minneapolis, USA, St. Paul, USA
64: Also at Karamanoğlu Mehmetbey University, Karaman, Turkey
65: Also at Utah Valley University, Orem, USA
66: Also at Purdue University, West Lafayette, USA
67: Also at Beykent University, Istanbul, Turkey, Istanbul, Turkey
68: Also at Bingol University, Bingol, Turkey
69: Also at Sinop University, Sinop, Turkey
70: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey
71: Also at Texas A&M University at Qatar, Doha, Qatar
72: Also at Kyungpook National University, Daegu, Korea, Daegu, Korea