HIN-18-018

$HeadURL$ $Id$

HIN-18-018

# Measurement of quark- and gluon-like jet fractions using jet charge in PbPb
and $\Pp\Pp$ collisions at 5.02

###### Abstract

The momentum-weighted sum of the electric charges of particles inside a jet,
known as jet charge, is sensitive to the electric charge of the particle
initiating the parton shower. This paper presents jet charge distributions in
$\sqrtsNN=5.02$ TeV lead-lead (PbPb) and proton-proton ($\Pp\Pp$) collisions
recorded with the CMS detector at the LHC. These data correspond to integrated
luminosities of 404and 27.4for PbPb and $\Pp\Pp$ collisions, respectively.
Leveraging the sensitivity of the jet charge to fundamental differences in the
electric charges of quarks and gluons, the jet charge distributions from
simulated events are used as templates to extract the quark- and gluon-like
jet fractions from data. The modification of these jet fractions is examined
by comparing $\Pp\Pp$ and PbPb data as a function of the overlap of the
colliding Pb nuclei (centrality). This measurement tests the color charge
dependence of jet energy loss due to interactions with the quark-gluon plasma.
No significant modification between different centrality classes and with
respect to $\Pp\Pp$ results is observed in the extracted quark- and gluon-like
jet fractions.

##  0.1 Introduction

High-momentum partons produced by hard scatterings in heavy ion collisions
undergo energy loss as they traverse the quark-gluon plasma (QGP) created in
these interactions [1]. The mechanisms by which these partons lose energy to
the medium, as well as their color dependence, are still not fully understood
[2, 3]. The particles resulting from the fragmentation and hadronization of
these partons can be clustered into jets. Jets are used as parton proxies to
examine the properties of the QGP. Parton energy loss manifests itself in
various experimental observables including the suppression of high transverse
momentum () hadrons and jets [4, 5, 6, 7, 8], as well as modifications of
parton showers [9, 10]. These phenomena are collectively referred to as jet
quenching [1].

At leading order in quantum chromodynamics, the type of parton that initiates
a jet can be distinguished. The resulting jet can therefore be labeled as a
quark, antiquark, or gluon jet. Several recent measurements indicate that the
fractions of quark and gluon jets in a sample may be modified as they are
expected to suffer different energy loss in the QGP due to their different
color charges [11, 12]. This analysis explores the extraction of the fractions
of quark and gluon jets from an inclusive jet sample in lead-lead (PbPb) and
proton-proton ($\Pp\Pp$) collisions. This is achieved with a template-fitting
method using the “jet charge“ observable. Jet charge, defined as the momentum-
weighted sum of the electric charges of particles inside a jet, is sensitive
to the electric charge of the particle initiating a parton shower and can be
used to discriminate between gluon- and quark-initiated jets. This observable
was initially suggested as a way of measuring the electric charge of a quark
[13] and was first measured in deep inelastic scattering experiments at
Fermilab [14, 15], CERN [16, 17, 18, 19], and Cornell University [20].

More recently, jet charge was measured at the LHC in $\Pp\Pp$ collisions by
the ATLAS [21] and CMS [22] Collaborations, characterizing the contributions
of quark and gluon fragmentation to jet production. At LHC energies, gluon
contributions dominate jet production at lower transverse momenta, while the
valence quark contributions overtake at higher jet [23]. According to
predictions from the event generator (version 6.424 [24], tune Z2 [25]) for
$\Pp\Pp$ collisions at 5.02, gluon jets are expected to constitute about 59%
of a sample of jets with transverse momenta above $120\GeV$. Similarly, up and
down (anti)quark jets are predicted to make up about 32% of the sample with
the other 9% arising from charm, strange and bottom (anti)quark jet
contributions. A detailed investigation of jet charge and its applications in
heavy ion collisions is motivated by extensive theoretical calculations [26,
27, 23]. The dependence of the mean and width (standard deviation) of the jet
charge distribution on both jet energy and size, can be calculated
independently of Monte Carlo (MC) fragmentation models despite the large
experimental uncertainty in fragmentation functions [28]. This makes jet
charge a suitable variable for the determination of quark and gluon jet
fractions.

This paper presents the first jet charge measurements in heavy ion collisions
along with $\Pp\Pp$ jet charge results at the same center-of-mass energy per
nucleon pair($\sqrtsNN$). The analysis uses PbPb and $\Pp\Pp$ data at
$\sqrtsNN=5.02$ , both collected in 2015 with the CMS detector at the CERN
LHC. The data correspond to an integrated luminosity of 404$\mubinv$
(27.4$\pbinv$) for PbPb ($\Pp\Pp$) collisions [29]. In heavy ion collisions,
the discrimination between jet and background constituents is not
straightforward and often impossible on a per-particle basis. In this work,
“background“ is defined as uncorrelated and long-range correlated
contributions [30], as measured at least 1.5 units of relative pseudorapidity
($\Delta\eta$) away from the jet axis [31, 32, 10], which do not arise from
the jet-initiating parton shower. Any short-range modifications to either the
medium or the jet structure are thus included in the jet “signal“. The
measurements are corrected for detector and background effects using an
unfolding procedure, and are presented as a function of the overlap of the
colliding Pb nuclei (centrality). The jet charge distributions of light
(anti)quark and gluon jets from MC generators are used as templates to fit the
inclusive jet charge distribution measured in data. The fractions of quark-
and gluon-initiated jets are extracted from this fitting procedure and are
referred to as quark- and gluon-like jet fractions. The results are presented
as a function of the minimum threshold of the particles used in the jet charge
measurement and also as a function of a weighting factor, $\kappa$ [26].

##  0.2 The CMS detector

The central feature of the CMS apparatus is a superconducting solenoid of 6m
internal diameter, providing 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 barrel and endcap sections. Two hadron
forward (HF) steel and quartz-fiber calorimeters complement the barrel and
endcap detectors, extending the calorimeter from the range $\abs{\eta}<3.0$
provided by the barrel and endcap out to $\abs{\eta}<5.2$. Events of interest
are selected using a two-tiered trigger system [33].

In this analysis, jets are reconstructed within the range $\abs{\eta}<1.5$. In
the region $\abs{\eta}<1.74$, the HCAL cells have widths of 0.087 in both
$\eta$ and azimuth $\phi$. Within the central barrel region corresponding to
$\abs{\eta}<1.48$, the HCAL cells map onto $5$$\times$$5$ ECAL crystal arrays
to form calorimeter towers projecting radially outwards from the nominal
interaction point. Within each tower, the energy deposits in ECAL and HCAL
cells are summed to define the calorimeter tower energies, which are
subsequently clustered to reconstruct the jet energies and directions [34].
The silicon tracker measures charged-particle tracks within $\abs{\eta}<2.5$.
It consists of 1440 silicon pixel and 15 148 silicon strip detector modules.
For charged particles with $1<\pt<10\GeV$ in the barrel region, the track
resolutions are typically 1.5% in and 25–90 (45–150)in the transverse
(longitudinal) impact parameter [35]. A 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. [36].

##  0.3 Event selection and simulated event samples

The PbPb and $\Pp\Pp$ data are selected with a calorimeter-based trigger that
uses the anti-jet clustering algorithm with a distance parameter of $R=0.4$
[37]. The trigger requires events to contain at least one jet with
$\pt>80\GeV$. This trigger is fully efficient for events containing jets with
reconstructed $\pt>100\GeV$. The data selected by this trigger are referred to
as “jet-triggered,“ and corresponds to 3.35 (2.6) million PbPb ($\Pp\Pp$)
collision events. Vertex and noise filters are applied to both PbPb and
$\Pp\Pp$ data to reduce contamination from noncollision events (, beam-gas
interactions), as described in previous analyses [38, 10]. Additionally, a
primary vertex with at least 2 tracks is required to be reconstructed and have
a $z$ position (${v_{z}}$) within 15cm of the center of the nominal
interaction region along the beam axis. In PbPb collisions, the shapes of
clusters in the pixel detector are required to be compatible with those
expected from a PbPb collision event. The PbPb events are also required to
have at least three towers in each of the HF calorimeters with energy deposits
of more than $3\GeV$ per tower.

Simulated MC samples are used to evaluate the performance of the event
reconstruction, in particular the track reconstruction efficiency and the jet
energy response and resolution. The MC samples use the (version 6.424 [24],
tune Z2 [25]) event generator to describe the hard scattering, parton
showering, and hadronization of the partons and are referred to as the 6
sample. To account for the soft underlying PbPb event, the hard 6 interactions
are embedded into simulated minimum-bias PbPb events produced with (version
1.383 [39]). This minimum-bias event generator is tuned to reproduce global
event properties such as the charged-hadron spectrum and particle
multiplicity. The combined sample of hard 6 interactions and soft underlying
event is referred to as the 6+sample. The [40] toolkit is used to simulate the
CMS detector response.

The scalar sum of the HF calorimeter towers ($3.0<\abs{\eta}<5.2$) is used to
define the event centrality in PbPb events and to divide the event sample into
centrality classes, each representing a percentage of the total inelastic
hadronic cross section [41]. Events in PbPb collisions are divided into four
centrality intervals corresponding to 0–10% (most central), 10–30%, 30–50%,
and 50–100% (most peripheral).

Because of the large number of nucleon-nucleon interactions in head-on PbPb
collisions, jets are more likely to be reconstructed in more central events.
Requiring a jet to be present in an event, therefore, biases the data sample
toward more central collisions. In comparison, the 6+sample consists of a flat
distribution of jets (from 6), as a function of centrality. Thus, a
centrality-based reweighting is applied to this MC sample to match the
centrality distribution of the jet-triggered PbPb data. An additional
reweighting procedure is performed to match the simulated $v_{z}$
distributions to data for both the PbPb and $\Pp\Pp$ samples. The contribution
of pile-up in both PbPb and $\Pp\Pp$ collisions is negligible [29].

##  0.4 Jet and track reconstruction

The jet reconstruction in PbPb and $\Pp\Pp$ events is performed with the anti-
jet algorithm with a distance parameter of $R=0.4$, as implemented in the
framework [42]. Individually calibrated calorimeter towers are used as inputs
to the algorithm. Only calorimeter information is used in the jet
reconstruction to minimize the bias of the tracking efficiency on the
reconstruction of jets. In PbPb collisions, the contributions of the
underlying event are subtracted using a two-iteration variant of the
“noise/pedestal subtraction“ technique described in Refs. [43, 44]. In this
method, only calorimeter towers outside of the jet area are used in the
background estimation after identifying and excluding the jets in the first
iteration. The underlying event and pile-up contribution is negligible in
$\Pp\Pp$ collisions and therefore do not require any subtraction. In both PbPb
and $\Pp\Pp$ events, jet energy is calibrated and the calorimeter response is
verified as a function of jet and $\eta$. To account for the variation in
detector response with the total number of jet constituents, additional
corrections are applied in both collision systems based on the number of
charged-particle tracks with $\pt>2\GeV$ within the jet cone (relative angular
distance from the jet axis
$\Delta\mathrm{r}=\sqrt{\smash[b]{(\Delta\eta)^{2}+(\Delta\phi)^{2}}}<0.4$),
the jet , and the collision centrality [10]. This corrects for a difference in
the simulated calorimetric jet energy response between quark and gluon jets
and reduces the difference in response between the two jet flavors from 10% to
around 3%. After reconstruction and offline jet energy calibration, jets are
required to have $\pt>120\GeV$ and $\abs{\eta}<1.5$. In this kinematic range,
the jet trigger is observed to be fully efficient and the jet energy response
and resolution is optimized. Within this selection, it is possible for
multiple jets to be selected from the same event.

For $\Pp\Pp$ collision events, charged-particle tracks are reconstructed using
an iterative tracking method [35] that finds tracks within $\abs{\eta}<2.4$
down to $\pt=0.1\GeV$. For the PbPb data an alternative iterative
reconstruction procedure is employed because of the large track multiplicities
[45, 46]. It is capable of reconstructing tracks down to $\pt=0.4\GeV$. The
charge of the particle is measured based on the direction of curvature of the
reconstructed track. Tracks used in this measurement are required to have a
relative uncertainty of less than 10% (30%) in PbPb ($\Pp\Pp$) collisions and
also satisfy the standard track quality requirements [38]. For both collision
systems, it is required that the significance of the distance of closest
approach to at least one primary vertex in the event be less than 3 standard
deviations, in order to decrease the likelihood of counting nonprimary charged
particles originating from secondary decay products. Tracks with $\pt>20\GeV$
are required to have an associated energy deposit [47] of at least half their
momentum in the calorimeters to reduce the contribution of misreconstructed
tracks with very high $\pt$. In PbPb collisions, tracks must additionally be
associated with at least 11 hits and satisfy a fit quality requirement that
the $\chi^{2}$, divided by both the number of degrees of freedom and the
number of tracker layers hit, be less than 0.15 [38]. The tracking efficiency
in $\Pp\Pp$ collisions is approximately 90% for $\pt>1\GeV$. Track
reconstruction is more difficult in the heavy ion environment because of the
large track multiplicity, and so the tracking efficiency ranges from
approximately 60% at $\pt=1\GeV$ to about 70% at $\pt=10\GeV$ [38].

##  0.5 Jet charge measurement

The jet charge is defined as:

$Q^{\kappa}=\frac{1}{(\pt^{\text{jet}})^{\kappa}}\sum_{i\in\text{jet}}{q_{i}}{p_{\mathrm{T},i}}^{\kappa}.$
(1)

The variable $\pt^{\text{jet}}$ is the transverse momentum of the calorimeter
jet. The $q_{i}$ and $p_{\mathrm{T},i}$ symbols refer to the electric charge
(in terms of the proton charge $e$) and transverse momentum of the i-th
particle in the jet cone, respectively. The $\kappa$ parameter controls the
weighting of the jet charge variable to low- and high-particles in the jet
cone. Low values of $\kappa$ enhance the contribution from low-particles to
the jet charge, and vice versa.

Tracks with $\pt>1\GeV$ that are located within the jet cone
($\Delta\mathrm{r}<0.4$) are used in the jet charge measurement. The track
threshold of 1ensures that the MC templates for different flavors used in the
fitting procedure are well resolved and also reduces the contributions of
uncorrelated and long-range correlated background to the jet charge.
Theoretical predictions suggest that a parameter value -weighting factor
$\kappa\approx 0.5$ is the most sensitive to the electric charge of the parton
initiating the jet in vacuum [26]. In this analysis, measurements are shown
for $\kappa$ values of 0.3, 0.5, and 0.7, and with different selections on the
minimum track of 1, 2, 4, and 5to retain a broad sensitivity to both hard and
soft radiation inside jets.

##  0.6 Corrections for background and detector effects

To allow for a comparison with future measurements from other experiments or
theoretical predictions, the jet charge distributions are unfolded from the
detector to the final-state hadron particle level. The jet charge measurements
at the detector level are broadened by track reconstruction inefficiencies,
and this effect increases with decreasing $\kappa$ values. In PbPb collisions,
there is additional smearing that is caused by the background from the
underlying event and long-range correlations [30]. The unfolding is performed
to account for these effects using the D’Agostini iterative method [48, 49,
50], as implemented in the RooUnfold software package [51]. Response matrices
are derived from 6 and 6+simulation samples for $\Pp\Pp$ and PbPb collisions,
respectively.

Response matrices in the unfolding procedure are constructed using jet charge
distributions measured with reconstructed tracks, and that measured with
generator-level particles originating from the hard scattering. To account for
the background effects in PbPb collisions, the reconstructed tracks used in
constructing the response matrices includes contributions from both the hard
scattering and background as modeled by 6+. As a cross check of the background
estimation procedure, a data-driven technique is also used to measure the
uncorrelated and long-range correlated contributions, as further discussed in
Section 0.8. No background correction is required in $\Pp\Pp$ collisions
because of the negligible underlying event and pile-up contribution [29].

The number of iterations in the unfolding procedure trades off bias towards MC
with statistical fluctuations. To obtain an optimal number of iterations,
reconstructed jet charge distributions from modified samples of 6 and 6+are
unfolded using the nominal response matrices. Quark and gluon jet fractions
are varied by $50\%$ in the modified simulation samples, which is expected to
give a good bound on the potential modification of the jet charge distribution
in data [23]. Based on these studies, three to four iterations are used in the
unfolding procedure for different selections of threshold track and $\kappa$.

##  0.7 Template fitting

The flavor-tagged jet charge distributions from 6 at the generator-level are
used as templates to fit the unfolded jet charge measurement to estimate the
fractions of quark and gluon jets. Measurements from 6 simulations for jets
initiated by up quarks ($\text{mean}=0.254e$, $\text{width}=0.341e$), down
quarks ($\text{mean}=-0.150e$, $\text{width}=0.335e$), and gluons
($\text{mean}=0.001e$, $\text{width}=0.364e$) are well separated and make up
the dominant fractions of the sample. The quoted mean and width values for the
different-flavor jets are from measurements at the generator-level, with a
minimum track threshold of 1and a $\kappa$ value of $0.5$. They have
statistical uncertainties of less than $0.1\%$. The average jet charge for
jets initiated by quarks and gluons varies by less than 1% as a function of
the jet in 6, allowing for the stable extraction of the respective jet
fractions in the range examined here. In the fitting procedure, the fractions
of up antiquark jets ($\cPaqu$) and down antiquark jets ($\cPaqd$), are varied
along with the up and down quark jets, respectively. Jets initiated by charm,
strange, and bottom (anti)quarks ($\cPaqc$, $\cPqc$, $\cPaqs$, $\cPqs$,
$\cPaqb$, and $\cPqb$, respectively) are categorized as “other flavor” jets
and their fractions are fixed during the fitting procedure to reduce the
number of degrees of freedom. The fitting procedure takes into consideration
the total systematic uncertainty in the jet charge measurements from all
sources combined with the statistical uncertainty.

A small fraction of jets have no reconstructed tracks inside the jet cone
above the threshold track used in the jet charge measurement. This fraction is
negligible for a track threshold of $1\GeV$ in both collision systems but goes
up to 10 (6)% in central PbPb ($\Pp\Pp$) collisions for a track threshold of
$5\GeV$. Such jets, with no reconstructed tracks inside the jet cone, are
excluded in the fitting procedure, and the fractions of quarks and gluons for
such jets are assigned directly from simulation. The related systematic
uncertainty is discussed in Section 0.8. Previous CMS results have shown a
large excess of soft particles in PbPb events relative to $\Pp\Pp$ events up
to $\Delta\mathrm{r}\sim 1$ from the jet axis, compensated by a relative
depletion of higher-$\pt$ tracks [10, 52]. Consequently, the fraction of jets
with no high-$\pt$ tracks is observed to be 50% higher in PbPb data compared
to 6+predictions for the most central collisions.

For a given jet energy, jets with a harder constituent spectrum are more
likely to be reconstructed because the calorimeter response does not scale
linearly with the incident particle energy, resulting in a bias toward the
selection of jets with fewer associated tracks. On average, quark jets have
harder fragmentation than gluon jets and are therefore preferentially
reconstructed. Jet energy corrections based on the number of jet constituents
are applied to reduce the difference in the response between quark and gluon
jets from 10 to around 3% (see Section 0.4). To compensate for the residual
difference, an extra correction factor, based on the deviation from unity in
the response, is applied to the extracted fractions of quark- and gluon-like
jets [10].

##  0.8 Systematic uncertainties

A number of sources of systematic uncertainty are considered, including
effects from the unfolding, tracking efficiencies, background correction, jet
reconstruction, and the contributions from “other flavor” jets. To estimate
most systematic uncertainties, a quantity is varied by an appropriate amount
in the construction of the response matrix and propagated through the full
analysis chain. The fitting procedure is repeated on the varied distributions
and the deviation from the nominal results are assigned as systematic
uncertainties. The systematic uncertainties from all sources are added in
quadrature. The relative uncertainties in the measured jet charge
distributions vary for different selections of -weighting factor $\kappa$ and
track threshold.

An uncertainty of 5 (4)% in PbPb ($\Pp\Pp$) data is considered to account for
possible differences in track reconstruction between data and simulation,
including reconstruction of misreconstructed tracks [38]. The reconstruction
efficiency is varied by this amount when populating the response matrices used
in the data unfolding. The resulting jet charge distributions are fit with the
generator-level templates and the differences in the extracted fractions of
quark- and gluon-like jets, observed to be 1–2%, are quoted as a source of
systematic uncertainty.

From simulation studies, the difference in the tracking efficiencies for
positively and negatively charged particles is found to be 0.5% in both PbPb
and $\Pp\Pp$ collisions regardless of the particle . This uncertainty is
propagated to the final result in a way similar to what is used for the
tracking reconstruction difference between data and simulation, , the
unfolding response matrices are modified and any differences after applying
the template fitting procedure are taken as systematic uncertainties.

To study the systematic effect arising from the choice of the MC event
generator to produce the response matrix used in the unfolding procedure, a
response matrix is formed using a modified 6 sample with varied quark and
gluon jet fractions, and both of these matrices are used to unfold the data.
In this study, quark and gluon jet fractions are varied by 50% from their
nominal MC values while populating the modified response matrices. The fitting
procedure is repeated on the resulting varied unfolded distributions and the
deviation from the nominal fitting results are then assigned as a systematic
uncertainty. Other sources of uncertainty in the unfolding procedure include
effects from bin-to-bin correlations in the unfolded distribution and the
statistical uncertainty in the MC simulation of the response matrix elements.
They are propagated using covariance matrices constructed with the RooUnfold
software package. These studies result in a relative uncertainty of 4–7% on
the extracted jet fractions. Additional studies are performed using 8 v212
[53] tune CUETP8M1 [54] and 2.7.1 [55] tune EE5C [56] event generators,
neither of which are observed to describe the jet spectra in $\Pp\Pp$ data
very well. After reweighting the jet spectra in these MC samples to match
data, while jet charge distributions from 8 are in very good agreement with
those from 6 and data, overestimates the width of the data jet charge
distributions and are hence not used in systematic uncertainty studies.

The systematic uncertainty due to the jet energy resolution is estimated by
changing the jet energy resolution by 5% to cover the corresponding
uncertainty [34], followed by a comparison of the modified spectra with the
nominal spectrum. The corresponding differences in the extracted quark- and
gluon-like jet fractions, estimated from repeating the fitting procedure on
the smeared jet charge distributions, are 1–3% and are included as systematic
uncertainties. The effects of the angular resolution of the jet axis are
negligible in the jet charge measurements.

To study the background modelling uncertainty in PbPb collisions, the response
matrices are also built using a data-driven reference event technique to
estimate the uncorrelated and long-range correlated background contributions.
The jet charge is measured using jets in a jet-triggered “signal“ event and
tracks from a separate minimum-bias “reference“ event which is required to
have a $v_{z}$ within 1cm and collision centrality within 2.5% of the signal
event. The signal and reference events must also have similar charged particle
multiplicities outside of the jet cone. The background obtained from the
reference event technique is observed to be in close agreement with that for
and the resulting uncertainty is less than $1\%$. No background subtraction is
performed in $\Pp\Pp$ due to its negligible effect, and hence no corresponding
systematic uncertainty is assigned.

The contribution from jets with no tracks in the jet cone above a threshold,
which are excluded in the fitting procedure, to the gluon-like jet fraction
measurements is assigned from MC. The difference in the fraction of such jets
between data and MC increases with increasing track threshold and with more
central collisions because of the observed depletion of high-$\pt$ tracks in
PbPb collisions [10, 52]. This difference is less than 1% in $\Pp\Pp$
collisions but can reach $4.5\%$ in PbPb collisions. It is assigned as a
systematic uncertainty.

In PbPb data, there is an additional bias toward selecting jets that are
reconstructed on upward fluctuations in the underlying event. Since the jet
spectrum is steeply falling, more jets on upward fluctuations are included in
the sample than jets on downward fluctuations are excluded resulting in an
uncertainty of up to $10\%$ in the measured particle multiplicity in central
PbPb events [10]. This effect is observed to be included in the reconstructed
jet charge measurements in simulation as well, so the difference in this bias
between data and MC is used to calculate the corresponding systematic
uncertainty. To calculate this difference, distributions of the particle
multiplicities within cones ($\Delta\mathrm{r}<0.4$), chosen randomly in
detector $\eta$ and $\phi$, are compared between minimum-bias data and MC
events [10, 52] and are found to be in very good agreement with each other.
The difference is propagated through the analysis chain and the resulting
deviation from the nominal results are observed to be negligible.

To assess the effects of the statistical uncertainties from the MC templates
on the final results, 1000 pseudo-experiments are performed by generating
smeared jet charge templates based on its statistical uncertainty and
repeatedly fitting the data measurements using these templates. The
distributions of extracted gluon-like jet fractions from the pseudo-experiment
fits have a variance of 3% or less, which is assigned as a systematic
uncertainty due to limited MC event count.

Finally, the effect of fixing the “other flavor” jet fractions in the fitting
procedure is analyzed. The “other flavor” jets, comprising c ($2.9\%$), s
($4.7\%$) and b ($1.7\%$) (anti)quarks, are each varied by their total amount
in the fitting procedure and the resulting deviation from the nominal fitting
result is propagated as a systematic uncertainty.

A summary of the range of systematic uncertainties for results is shown in
Table 0.8 for different selections of $\kappa$ and track threshold values.

Relative systematic uncertainties in percentage for the measurements of gluon-
like jet fractions in $\Pp\Pp$ and PbPb events. The PbPb results are given in
intervals of centrality. When an uncertainty range is given, the range of the
values are the maximum variation in the fractions for different selections on
$\kappa$ and track threshold values.  $\Pp\Pp$ PbPb centrality intervals
Source 50–100% 30–50% 10–30% 0–10% Response matrix modelling 4–6 5–7.5 5–7.5
5–7.5 5–7.5 Monte Carlo event count 1.5 3 3 3 3 Jet energy resolution 1–1.5 2
2 2–3 2–3 Tracking efficiency (data/simulation) 1 2 2 2 2 Tracking efficiency
(positive/negative) 0.5–1 1–1.5 1–1.5 0.5–1.5 0.5–1.5 Jets with no tracks 0.1
0.2–1 0.4–2 0.4–3 0.5–4.5 Unfolding procedure 0.5 0.7 0.8 1.1 1.4 Background
modelling and fluctuation — 0.5 0.5 1 1 “Other flavor” jets 1 1 1 1 1 Total
4–5 7–8 7–8 7–8 7–9

##  0.9 Results

The unfolded jet charge measurements, normalized to the total number of jets
in the sample ($N_{\text{jets}}$), are shown in the upper panels of Fig. 1
with solid black points for a sample selection with a minimum track of 1and
-weighting factor $\kappa=0.5$. The results are shown for $\Pp\Pp$ and
different event centrality bins in PbPb. The extracted fraction of quark- and
gluon-initiated jets is displayed as a set of stacked histograms. Figure 1
also shows the ratio of the data over the template fit results in the lower
panels, and no significant deviation from unity is observed in the entire
fitting range. The fractions of up and down quarks are observed to be
significantly different between pp and PbPb collisions, as expected from an
enhanced contribution of valence down quarks in lead collisions (having 126
neutrons and 82 protons in each nucleus). The jet charge measurements and fit
results for other minimum track and $\kappa$ selections are shown in figures
5-7 in the appendix.

Figure 1: (Upper) Unfolded jet charge measurements shown for inclusive jets in
data along with the extracted fractions of up, and down quark jets, gluon
jets, and the “other flavor” jets. The systematic and statistical
uncertainties in the distributions are shown by the shaded regions and
vertical bars, respectively. The jet charge measurements shown here are for
the $\pt$-weighting factor $\kappa=0.5$ and a minimum track of 1. (Lower)
Ratio of the jet charge measurements to the results of template fits.

The widths (standard deviations) of the unfolded data jet charge distributions
in different PbPb event centrality bins and in $\Pp\Pp$, with various track
thresholds and $\kappa$ values, are shown in Fig. 2. They are also compared to
generator-level predictions from 6 with matching track and $\kappa$ selections
in Fig. 2. The data (simulation) results for $\kappa=0.3$, 0.5, and 0.7, are
shown by the blue squares (solid lines), red crosses (dashed lines), and green
diamonds (dotted lines), respectively. The measured standard deviations tend
to increase as a function of the minimum track and decrease with increasing
$\kappa$ value. Theoretical predictions incorporating color-charge dependence
into jet energy loss calculations predict that stronger quenching of gluon
jets will result in a reduced fraction of gluon-initiated jets in the observed
jet sample from PbPb collisions compared to that in $\Pp\Pp$ data [27]. The
mean of the jet charge distribution for gluon-initiated jets is consistently
predicted to be zero in various MC simulations, while that of quark jets is
nonzero. A decrease in the fraction of gluons in a quenched jet sample would
hence lead to an effective increase in the standard deviation of the measured
jet charge distribution. Figure 2 summarizes standard deviations measured for
all track selections and $\kappa$ values studied. The generator-level 6
predictions agree with the measured widths for $\Pp\Pp$ events. No strong
modifications are observed in the widths of the jet charge distributions in
central PbPb collisions compared to the peripheral events. While the PbPb
width results cannot be directly compared to the $\Pp\Pp$ reference due to
different up and down quark contents in protons and Pb nuclei, generator-level
6 predictions adjusted for this difference reproduce the observed widths of
jet charge measurements for all PbPb collision centralities.

Figure 2: The standard deviation of the jet charge distributions with
different track thresholds and $\kappa$ values for $\Pp\Pp$ collisions and in
the various event centrality bins for PbPb collisions compared with the 6
prediction. The systematic and statistical uncertainties in the standard
deviation measurements are shown by the shaded regions and vertical bars,
respectively.

The results for the quark- and gluon-like jet fractions in an inclusive sample
are shown in Fig. 3 as a function of the track threshold. Figure 4 shows the
same quantities as a function of $\kappa$ for track $\pt>1$ and $>$2, with red
circles and blue crosses, respectively. The systematic uncertainties are shown
by the shaded regions while the statistical uncertainties, combined with the
fit uncertainties, are shown by the solid vertical bars. Only the gluon jet
fitting results are shown in Figs. 3 and 4 for clarity but it should be
inferred that the quark jets make up the rest of the inclusive sample.

Figure 3: Fitting results for the extraction of gluon-like jet fractions in
$\Pp\Pp$ and PbPb data shown for different track threshold values and event
centrality bins in PbPb collisions. The systematic and statistical
uncertainties are represented by the shaded regions and vertical bars,
respectively. The predictions for the gluon jet fractions from 6 are shown in
dashed red lines. Figure 4: Fitting results for the extraction of gluon-like
jet fractions in $\Pp\Pp$ and PbPb data shown for -weighting factor $\kappa$
values of 0.3, 0.5, and 0.7 in different event centrality bins in PbPb. The
markers for track $\pt>1$ and $>$2have been separated horizontally for
clarity. The systematic and statistical uncertainties are represented by the
shaded regions and vertical bars, respectively. The predictions for the gluon
jet fractions from 6 are shown in dashed red lines.

Previous CMS measurements have shown a strong modification in the distribution
of low-tracks relative to the jet axis in PbPb collisions with respect to
$\Pp\Pp$ collisions [10, 52]. In-medium gluon radiation and a wake-like
response of the QGP to the propagating parton are two of the proposed
explanations for this modification [57], neither of which are expected to
modify the jet charge considerably. From Figs. 3 and 4, no significant
modification is observed in the relative fractions of the quark- and gluon-
like jets in central PbPb collisions compared to peripheral PbPb and $\Pp\Pp$
collisions. The relative jet fractions are also observed to be unmodified when
calculated using a range of different track thresholds or $\kappa$ values.

##  0.10 Summary

Jet charge, defined as the momentum-weighted sum of the electric charges of
particles inside a jet, is measured for the first time in heavy ion collisions
and is presented along with $\Pp\Pp$ results at the same energy. The analysis
uses lead-lead (PbPb) and proton-proton ($\Pp\Pp$) collision data collected
with the CMS detector at a nucleon-nucleon center-of-mass energy of 5.02. The
unfolded jet charge distributions, measured using the jet constituents with
transverse momentum $\pt>1\GeV$ for jets having $\pt>120\GeV$ and
pseudorapidity $\abs{\eta}<1.5$, are presented. The widths of the jet charge
distributions for $\Pp\Pp$ collisions are in good agreement with predictions
from the event generator 6 and are shown to be independent of PbPb collision
centrality. The jet charge distributions for quark- and gluon-initiated jets
from 6 events are used as fitting templates to estimate the respective
contributions in the measured jet samples. The gluon-like jet fractions
extracted from these template fits are found to be similar between $\Pp\Pp$
data and all studied PbPb centrality ranges. These are the first measurements
in heavy ion collisions which exploit the electric charge of the initiating
parton to discriminate between quark and gluon jets. No evidence is seen for a
significant decrease (increase) in gluon-like (quark-like) prevalence in a
sample of jets with $\pt>120\GeV$ in PbPb collisions. These observations do
not support recent interpretations of other heavy ion results [11, 12], which
are based on a decreased (increased) gluon (quark) fraction caused by color-
charge dependent jet quenching.

###### 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 centers 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 (Ukraine); STFC (United Kingdom); DOE and NSF (USA).
Individuals have received support from the Marie-Curie program and the
European Research Council and Horizon 2020 Grant, contract Nos. 675440,
752730, 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. Z191100007219010; the
Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the
Deutsche Forschungsgemeinschaft (DFG) under Germany’s Excellence Strategy –
EXC 2121 “Quantum Universe” – 390833306; the Lendület (“Momentum”) Program 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 program of
the Foundation for Polish Science, cofinanced from European Union, Regional
Development Fund, the Mobility Plus program 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 Ministry of Science and
Education, grant no. 14.W03.31.0026 (Russia); the Tomsk Polytechnic University
Competitiveness Enhancement Program and “Nauka” Project FSWW-2020-0008
(Russia); 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 programs
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
Kavli Foundation; the Nvidia Corporation; the SuperMicro Corporation; the
Welch Foundation, contract C-1845; and the Weston Havens Foundation (USA).

## References

  * [1] J. D. Björken, “Energy loss of energetic partons in QGP: possible extinction of high $\pt$ jets in hadron-hadron collisions”, (1982). FERMILAB-PUB-82-059-THY.
  * [2] J. Casalderrey-Solana and C. A. Salgado, “Introductory lectures on jet quenching in heavy ion collisions”, in  Theoretical physics. Proceedings, 47th Cracow School, Zakopane, Poland, June 14-22, 2007, p. 3661.  2007\.  arXiv:0712.3443.
  * [3] A. Majumder and M. Van Leeuwen, “The theory and phenomenology of perturbative QCD based jet quenching”,  Prog. Part. Nucl. Phys. 66 (2011) 41, 10.1016/j.ppnp.2010.09.001, arXiv:1002.2206.
  * [4] STAR Collaboration, “Direct observation of dijets in central Au+Au collisions at $\sqrtsNN$ = 200 GeV”,  Phys. Rev. Lett. 97 (2006) 162301, 10.1103/PhysRevLett.97.162301, arXiv:nucl-ex/0604018.
  * [5] ATLAS Collaboration, “Observation of a centrality-dependent dijet asymmetry in lead-lead collisions at ${\sqrtsNN=2.76\TeV}$ with the ATLAS detector at the LHC”,  Phys. Rev. Lett. 105 (2010) 252303, 10.1103/PhysRevLett.105.252303, arXiv:1011.6182.
  * [6] CMS Collaboration, “Observation and studies of jet quenching in PbPb collisions at $\sqrtsNN=2.76\TeV$”,  Phys. Rev. C 84 (2011) 024906, 10.1103/PhysRevC.84.024906, arXiv:1102.1957.
  * [7] PHENIX Collaboration, “Suppressed ${\pi}^{0}$ production at large transverse momentum in central $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrtsNN=200\GeV$”,  Phys. Rev. Lett. 91 (Aug, 2003) 072301, 10.1103/PhysRevLett.91.072301, arXiv:nucl-ex/0304022v1.
  * [8] ALICE Collaboration, “Measurement of jet suppression in central PbPb collisions at $\sqrtsNN=2.76\TeV$”,  Phys. Lett. B 746 (2015) 1, 10.1016/j.physletb.2015.04.039, arXiv:1502.01689.
  * [9] ATLAS Collaboration, “Measurement of jet fragmentation in pb+pb and $pp$ collisions at $\sqrt{{s}_{NN}}=5.02$ tev with the atlas detector”,  Phys. Rev. C 98 (Aug, 2018) 024908, 10.1103/PhysRevC.98.024908, arXiv:1805.05424.
  * [10] CMS Collaboration, “Jet properties in PbPb and pp collisions at $\sqrtsNN=5.02\TeV$”,  JHEP 05 (2018) 006, 10.1007/JHEP05(2018)006, arXiv:1803.00042.
  * [11] M. Spousta and B. Cole, “Interpreting single jet measurements in PbPb collisions at the LHC”,  Eur. Phys. J. C 76 (2016) 50, 10.1140/epjc/s10052-016-3896-0, arXiv:1504.05169v1.
  * [12] ALICE Collaboration, “Exploration of jet substructure using iterative declustering in pp and PbPb collisions at LHC energies”,  Phys. Lett. B 802 (2020) 135227, 10.1016/j.physletb.2020.135227, arXiv:1905.02512.
  * [13] R. D. Field and R. P. Feynman, “A parametrization of the properties of quark jets”,  Nucl. Phys. B 136 (1978) 76, 10.1016/0550-3213(78)90015-9.
  * [14] Fermilab–Serpukhov–Moscow–Michigan Collaboration, “Net charge in deep inelastic antineutrino-nucleon scattering”,  Phys. Lett. B 91 (1980) 311, 10.1016/0370-2693(80)90456-6.
  * [15] Fermilab–Serpukhov–Moscow–Michigan Collaboration, “Quark jets from antineutrino interactions (I). Net charge and factorization in the quark jets”,  Nucl. Phys. B 184 (1981) 13, 10.1016/0550-3213(81)90207-8.
  * [16] Aachen–Bonn–CERN–Munich–Oxford Collaboration, “Multiplicity distributions in neutrino-hydrogen interactions”,  Nucl. Phys. B 181 (1981) 385, 10.1016/0550-3213(81)90532-0.
  * [17] Aachen–Bonn–CERN–Munich–Oxford Collaboration, “Charge properties of the hadronic system in $\nu p$ and $\overline{\nu}p$ interactions”,  Phys. Lett. B 112 (1982) 88, 10.1016/0370-2693(82)90912-1.
  * [18] European Muon Collaboration, “Quark charge retention in final state hadrons from deep inelastic muon scattering”,  Phys. Lett. B 144 (1984) 302, 10.1016/0370-2693(84)91825-2.
  * [19] Amsterdam–Bologna–Padua–Pisa–Saclay–Turin Collaboration, “Charged hadron multiplicities in high-energy $\overline{\nu}_{\mu}n$ and $\overline{\nu}_{\mu}p$ interactions”,  Z. Phys. C 11 (1982) 283, 10.1007/BF01578279. [Erratum: 10.1007/BF01571828].
  * [20] R. Erickson et al., “Charge retention in deep-inelastic electroproduction”,  Phys. Rev. Lett. 42 (1979) 822, 10.1103/PhysRevLett.42.822. [Erratum: 10.1103/PhysRevLett.42.1246].
  * [21] ATLAS Collaboration, “Measurement of jet charge in dijet events from $\sqrt{\mathrm{s}}=8~{}\TeV$ pp collisions with the ATLAS detector”,  Phys. Rev. D 93 (2016) 052003, 10.1103/physrevd.93.052003, arXiv:1509.05190.
  * [22] CMS Collaboration, “Measurements of jet charge with dijet events in pp collisions at $\sqrt{\mathrm{s}}=8~{}\TeV$”,  JHEP 10 (2017) 131, 10.1007/jhep10(2017)131, arXiv:1706.05868.
  * [23] H. T. Li and I. Vitev, “Jet charge modification in dense QCD matter”,  Phys. Rev. D 101 (2020) 076020, 10.1103/PhysRevD.101.076020, arXiv:1908.06979.
  * [24] T. Sjöstrand, S. Mrenna, and P. Skands, “PYTHIA 6.4 physics and manual”,  JHEP 05 (2006) 026, 10.1088/1126-6708/2006/05/026, arXiv:hep-ph/0603175.
  * [25] R. Field, “Early LHC underlying event data — findings and surprises”, in  Hadron collider physics. Proceedings, 22nd Conference, HCP 2010, Toronto, Canada.  2010\.  arXiv:1010.3558.
  * [26] W. J. Waalewijn, “Calculating the charge of a jet”,  Phys. Rev. D 86 (2012) 094030, 10.1103/PhysRevD.86.094030, arXiv:1209.3019.
  * [27] S.-Y. Chen, B.-W. Zhang, and E. Wang, “Jet charge in high-energy nuclear collisions”,  Chinese Physics C 44 (2020) 024103, 10.1088/1674-1137/44/2/024103, arXiv:1908.01518.
  * [28] D. Krohn, M. D. Schwartz, T. Lin, and W. J. Waalewijn, “Jet charge at the LHC”,  Phys. Rev. Lett. 110 (2013) 212001, 10.1103/PhysRevLett.110.212001, arXiv:1209.2421.
  * [29] CMS Collaboration, “CMS luminosity calibration for the pp reference run at $\sqrt{s}=5.02~{}\mathrm{TeV}$”, CMS Physics Analysis Summary CMS-PAS-LUM-16-001, 2016.
  * [30] CMS Collaboration, “Long-range and short-range dihadron angular correlations in central PbPb collisions at $\sqrtsNN=2.76\TeV$”,  JHEP 07 (2011) 076, 10.1007/JHEP07(2011)076, arXiv:1105.2438.
  * [31] CMS Collaboration, “Decomposing transverse momentum balance contributions for quenched jets in PbPb collisions at $\sqrtsNN=2.76\TeV$”,  JHEP 11 (2016) 055, 10.1007/JHEP11(2016)055, arXiv:1609.02466.
  * [32] CMS Collaboration, “Correlations between jets and charged particles in PbPb and pp collisions at $\sqrtsNN=2.76\TeV$”,  JHEP 02 (2016) 156, 10.1007/JHEP02(2016)156, arXiv:1601.00079.
  * [33] CMS Collaboration, “The CMS trigger system”,  JINST 12 (2017) P01020, 10.1088/1748-0221/12/01/P01020, arXiv:1609.02366.
  * [34] CMS Collaboration, “Determination of jet energy calibration and transverse momentum resolution in CMS”,  JINST 6 (2011) P11002, 10.1088/1748-0221/6/11/P11002, arXiv:1107.4277.
  * [35] CMS Collaboration, “Description and performance of track and primary-vertex reconstruction with the CMS tracker”,  JINST 9 (2014) P10009, 10.1088/1748-0221/9/10/P10009, arXiv:1405.6569.
  * [36] CMS Collaboration, “The CMS experiment at the CERN LHC”,  JINST 3 (2008) S08004, 10.1088/1748-0221/3/08/S08004.
  * [37] M. Cacciari, G. P. Salam, and G. Soyez, “The anti-jet clustering algorithm”,  JHEP 04 (2008) 063, 10.1088/1126-6708/2008/04/063, arXiv:0802.1189.
  * [38] CMS Collaboration, “Charged particle nuclear modification factors in PbPb and pPb collisions at $\sqrtsNN=5.02\TeV$”,  JHEP 04 (2017) 039, 10.1007/JHEP04(2017)039, arXiv:1611.01664.
  * [39] I. P. Lokhtin and A. M. Snigirev, “A model of jet quenching in ultrarelativistic heavy ion collisions and high-$p_{\rm T}$ hadron spectra at RHIC”,  Eur. Phys. J. C 45 (2006) 211, 10.1140/epjc/s2005-02426-3, arXiv:hep-ph/0506189.
  * [40] GEANT4 Collaboration, “GEANT4 — a simulation toolkit”,  Nucl. Instrum. Meth. A 506 (2003) 250, 10.1016/S0168-9002(03)01368-8.
  * [41] CMS Collaboration, “Jet momentum dependence of jet quenching in PbPb collisions at $\sqrtsNN=2.76\TeV$”,  Phys. Lett. B 712 (2012) 176, 10.1016/j.physletb.2012.04.058, arXiv:1202.5022.
  * [42] M. Cacciari, G. P. Salam, and G. Soyez, “FastJet user manual”,  Eur. Phys. J. C 72 (2012) 1896, 10.1140/epjc/s10052-012-1896-2, arXiv:1111.6097.
  * [43] M. Cacciari and G. P. Salam, “Pileup subtraction using jet areas”,  Phys. Lett. B 659 (2008) 119, 10.1016/j.physletb.2007.09.077, arXiv:0707.1378.
  * [44] O. Kodolova, I. Vardanian, A. Nikitenko, and A. Oulianov, “The performance of the jet identification and reconstruction in heavy ions collisions with CMS detector”,  Eur. Phys. J. C 50 (2007) 117, 10.1140/epjc/s10052-007-0223-9.
  * [45] CMS Collaboration, “Study of high-$p_{\rm T}$ charged particle suppression in PbPb compared to pp collisions at $\sqrtsNN=2.76\TeV$”,  Eur. Phys. J. C 72 (2012) 1945, 10.1140/epjc/s10052-012-1945-x, arXiv:1202.2554.
  * [46] CMS Collaboration, “Modification of jet shapes in PbPb collisions at $\sqrtsNN=2.76\TeV$”,  Phys. Lett. B 730 (2014) 243, 10.1016/j.physletb.2014.01.042, arXiv:1310.0878.
  * [47] CMS Collaboration, “Particle-flow reconstruction and global event description with the CMS detector”,  JINST 12 (2017) P10003, 10.1088/1748-0221/12/10/P10003, arXiv:1706.04965.
  * [48] G. D’Agostini, “A multidimensional unfolding method based on Bayes’ theorem”,  Nucl. Instrum. Meth. A 362 (1995) 487, 10.1016/0168-9002(95)00274-X.
  * [49] W. H. Richardson, “Bayesian-based iterative method of image restoration”,  Opt. Soc. Am. 62 (1972) 55, 10.1364/JOSA.62.000055.
  * [50] L. B. Lucy, “An iterative technique for the rectification of observed distributions”,  Astron. J. 79 (1974) 745, 10.1086/111605.
  * [51] T. Adye, “Unfolding algorithms and tests using RooUnfold”, in  Proceedings of the PHYSTAT 2011 Workshop, CERN, Geneva, Switzerland, January 2011, CERN-2011-006, p. 313.  2011\.  arXiv:1105.1160.
  * [52] CMS Collaboration, “Measurement of transverse momentum relative to dijet systems in PbPb and pp collisions at $\sqrtsNN=2.76\TeV$”,  JHEP 01 (2016) 006, 10.1007/JHEP01(2016)006, arXiv:1509.09029.
  * [53] T. Sjöstrand et al., “An Introduction to PYTHIA 8.2”,  Comput. Phys. Commun. 191 (2015) 159, 10.1016/j.cpc.2015.01.024, arXiv:1410.3012.
  * [54] CMS Collaboration, “Event generator tunes obtained from underlying event and multiparton scattering measurements”,  Eur. Phys. J. C 76 (2016) 155, 10.1140/epjc/s10052-016-3988-x, arXiv:1512.00815.
  * [55] M. Bähr et al., “Herwig++ physics and manual”,  Eur. Phys. J. C 58 (2008) 639, 10.1140/epjc/s10052-008-0798-9, arXiv:0803.0883.
  * [56] M. H. Seymour and A. Siodmok, “Constraining MPI models using $\sigma_{eff}$ and recent Tevatron and LHC underlying event data”,  JHEP 10 (2013) 113, 10.1007/JHEP10(2013)113, arXiv:1307.5015.
  * [57] J. Casalderrey-Solana et al., “Angular structure of jet quenching within a hybrid strong/weak coupling model”,  JHEP 03 (2017) 135, 10.1007/JHEP03(2017)135, arXiv:1609.05842.

##  .11 Jet charge measurements

Figure 5: (Upper row of each figure) Unfolded jet charge measurements shown
for inclusive jets in data along with the extracted fractions of up, and down
quark jets, gluon jets, and the “other flavor” jets. The systematic and
statistical uncertainties in the distributions are shown by the shaded regions
and vertical bars, respectively. The jet charge measurements shown here are
for $\kappa=0.5$ and a minimum track of 2, 4, and 5(top, middle, and bottom,
respectively). (Lower row of each figure) Ratio of the jet charge measurements
to the results of template fits.

Figure 6: (Upper row of each figure) Unfolded jet charge measurements shown
for inclusive jets in data along with the extracted fractions of up, and down
quark jets, gluon jets, and the “other flavor” jets. The systematic and
statistical uncertainties in the distributions are shown by the shaded regions
and vertical bars, respectively. The jet charge measurements shown here are
for a minimum track of 1and a $\kappa$ value of 0.3, 0.5, and 0.7 (top,
middle, and bottom, respectively). (Lower row of each figure) Ratio of the jet
charge measurements to the results of template fits.

Figure 7:  (Upper row of each figure) Unfolded jet charge measurements shown
for inclusive jets in data along with the extracted fractions of up, and down
quark jets, gluon jets, and the “other flavor” jets. The systematic and
statistical uncertainties in the distributions are shown by the shaded regions
and vertical bars, respectively. The jet charge measurements shown here are
for a minimum track of 2and a $\kappa$ value of 0.3, 0.5, and 0.7 (top,
middle, and bottom, respectively). (Lower row of each figure) Ratio of the jet
charge measurements to the results of template fits.

##  .12 The CMS Collaboration

Yerevan Physics Institute, Yerevan, Armenia
A.M. Sirunyan${}^{\textrm{\textdagger}}$, A. Tumasyan Institut für
Hochenergiephysik, Wien, Austria
W. Adam, F. Ambrogi, T. Bergauer, M. Dragicevic, J. Erö, A. Escalante Del
Valle, M. Flechl, R. Frühwirth1, M. Jeitler1, N. Krammer, I. Krätschmer, D.
Liko, T. Madlener, I. Mikulec, N. Rad, J. Schieck1, R. Schöfbeck, M. Spanring,
W. Waltenberger, C.-E. Wulz1, M. Zarucki Institute for Nuclear Problems,
Minsk, Belarus
V. Drugakov, V. Mossolov, J. Suarez Gonzalez Universiteit Antwerpen,
Antwerpen, Belgium
M.R. Darwish, E.A. De Wolf, D. Di Croce, X. Janssen, A. Lelek, M. Pieters, H.
Rejeb Sfar, H. Van Haevermaet, P. Van Mechelen, S. Van Putte, N. Van Remortel
Vrije Universiteit Brussel, Brussel, Belgium
F. Blekman, E.S. Bols, S.S. Chhibra, J. D’Hondt, J. De Clercq, D. Lontkovskyi,
S. Lowette, I. Marchesini, S. Moortgat, Q. Python, S. Tavernier, W. Van
Doninck, P. Van Mulders Université Libre de Bruxelles, Bruxelles, Belgium
D. Beghin, B. Bilin, B. Clerbaux, G. De Lentdecker, H. Delannoy, B. Dorney, L.
Favart, A. Grebenyuk, A.K. Kalsi, L. Moureaux, A. Popov, N. Postiau, E.
Starling, L. Thomas, C. Vander Velde, P. Vanlaer, D. Vannerom Ghent
University, Ghent, Belgium
T. Cornelis, D. Dobur, I. Khvastunov2, M. Niedziela, C. Roskas, K. Skovpen, M.
Tytgat, W. Verbeke, B. Vermassen, M. Vit Université Catholique de Louvain,
Louvain-la-Neuve, Belgium
O. Bondu, G. Bruno, C. Caputo, P. David, C. Delaere, M. Delcourt, A.
Giammanco, V. Lemaitre, J. Prisciandaro, A. Saggio, M. Vidal Marono, P.
Vischia, J. Zobec Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro,
Brazil
G.A. Alves, G. Correia Silva, C. Hensel, A. Moraes 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, J. Martins5, D. Matos Figueiredo, M. Medina
Jaime6, M. Melo De Almeida, C. Mora Herrera, L. Mundim, H. Nogima, W.L. Prado
Da Silva, P. Rebello Teles, 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
C.A. Bernardesa, L. Calligarisa, T.R. Fernandez Perez Tomeia, E.M. Gregoresb,
D.S. Lemos, P.G. Mercadanteb, S.F. Novaesa, SandraS. Padulaa Institute for
Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia,
Bulgaria
A. Aleksandrov, G. Antchev, R. Hadjiiska, P. Iaydjiev, M. Misheva, M. Rodozov,
M. Shopova, G. Sultanov University of Sofia, Sofia, Bulgaria
M. Bonchev, A. Dimitrov, T. Ivanov, L. Litov, B. Pavlov, P. Petkov, A. Petrov
Beihang University, Beijing, China
W. Fang7, X. Gao7, L. Yuan Department of Physics, Tsinghua University,
Beijing, China
M. Ahmad, Z. Hu, Y. Wang Institute of High Energy Physics, Beijing, China
G.M. Chen8, H.S. Chen8, M. Chen, C.H. Jiang, D. Leggat, H. Liao, Z. Liu, A.
Spiezia, J. Tao, E. Yazgan, H. Zhang, S. Zhang8, J. Zhao State Key Laboratory
of Nuclear Physics and Technology, Peking University, Beijing, China
A. Agapitos, Y. Ban, G. Chen, A. Levin, J. Li, L. Li, Q. Li, Y. Mao, S.J.
Qian, D. Wang, Q. Wang Zhejiang University, Hangzhou, China
M. Xiao Universidad de Los Andes, Bogota, Colombia
C. Avila, A. Cabrera, C. Florez, C.F. González Hernández, M.A. Segura Delgado
Universidad de Antioquia, Medellin, Colombia
J. Mejia Guisao, J.D. Ruiz Alvarez, C.A. Salazar González, N. Vanegas Arbelaez
University of Split, Faculty of Electrical Engineering, Mechanical Engineering
and Naval Architecture, Split, Croatia
D. Giljanović, 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, M. Roguljic, A. Starodumov9,
T. Susa University of Cyprus, Nicosia, Cyprus
M.W. Ather, A. Attikis, E. Erodotou, A. Ioannou, M. Kolosova, S. Konstantinou,
G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis, H.
Rykaczewski, H. Saka, D. Tsiakkouri Charles University, Prague, Czech Republic
M. Finger10, M. Finger Jr.10, A. Kveton, J. Tomsa 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
M.A. Mahmoud11,12, Y. Mohammed11 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, L. Forthomme, H. Kirschenmann, K. Osterberg, M. Voutilainen
Helsinki Institute of Physics, Helsinki, Finland
F. Garcia, J. Havukainen, J.K. Heikkilä, V. Karimäki, M.S. Kim, R. Kinnunen,
T. Lampén, K. Lassila-Perini, S. Laurila, S. Lehti, T. Lindén, H. Siikonen, E.
Tuominen, J. Tuominiemi Lappeenranta University of Technology, Lappeenranta,
Finland
P. Luukka, T. Tuuva IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
M. Besancon, F. Couderc, M. Dejardin, D. Denegri, B. Fabbro, J.L. Faure, F.
Ferri, S. Ganjour, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry,
C. Leloup, B. Lenzi, E. Locci, J. Malcles, J. Rander, A. Rosowsky, M.Ö. Sahin,
A. Savoy-Navarro13, M. Titov, G.B. Yu Laboratoire Leprince-Ringuet,
CNRS/IN2P3, Ecole Polytechnique, Institut Polytechnique de Paris
S. Ahuja, C. Amendola, F. Beaudette, P. Busson, C. Charlot, B. Diab, G.
Falmagne, R. Granier de Cassagnac, I. Kucher, A. Lobanov, C. Martin Perez, M.
Nguyen, C. Ochando, P. Paganini, J. Rembser, R. Salerno, J.B. Sauvan, Y.
Sirois, A. Zabi, A. Zghiche Université de Strasbourg, CNRS, IPHC UMR 7178,
Strasbourg, France
J.-L. Agram14, J. Andrea, D. Bloch, G. Bourgatte, J.-M. Brom, E.C. Chabert, C.
Collard, E. Conte14, J.-C. Fontaine14, D. Gelé, U. Goerlach, C. Grimault, 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, C. Camen, A. Carle, N. Chanon, R.
Chierici, D. Contardo, P. Depasse, H. El Mamouni, J. Fay, S. Gascon, M.
Gouzevitch, B. Ille, Sa. Jain, I.B. Laktineh, H. Lattaud, A. Lesauvage, M.
Lethuillier, L. Mirabito, S. Perries, V. Sordini, L. Torterotot, G. Touquet,
M. Vander Donckt, S. Viret Georgian Technical University, Tbilisi, Georgia
A. Khvedelidze10 Tbilisi State University, Tbilisi, Georgia
Z. Tsamalaidze10 RWTH Aachen University, I. Physikalisches Institut, Aachen,
Germany
C. Autermann, L. Feld, K. Klein, M. Lipinski, D. Meuser, A. Pauls, M. Preuten,
M.P. Rauch, J. Schulz, M. Teroerde RWTH Aachen University, III. Physikalisches
Institut A, Aachen, Germany
M. Erdmann, B. Fischer, S. Ghosh, T. Hebbeker, K. Hoepfner, H. Keller, L.
Mastrolorenzo, M. Merschmeyer, A. Meyer, P. Millet, G. Mocellin, S. Mondal, S.
Mukherjee, D. Noll, A. Novak, T. Pook, A. Pozdnyakov, T. Quast, M. Radziej, Y.
Rath, H. Reithler, J. Roemer, A. Schmidt, S.C. Schuler, A. Sharma, S.
Wiedenbeck, S. Zaleski RWTH Aachen University, III. Physikalisches Institut B,
Aachen, Germany
G. Flügge, W. Haj Ahmad15, O. Hlushchenko, T. Kress, T. Müller, A. Nowack, C.
Pistone, O. Pooth, D. Roy, H. Sert, A. Stahl16 Deutsches Elektronen-
Synchrotron, Hamburg, Germany
M. Aldaya Martin, P. Asmuss, I. Babounikau, H. Bakhshiansohi, K. Beernaert, O.
Behnke, A. Bermúdez Martínez, A.A. Bin Anuar, K. Borras17, V. Botta, A.
Campbell, A. Cardini, P. Connor, S. Consuegra Rodríguez, C. Contreras-Campana,
V. Danilov, A. De Wit, M.M. Defranchis, C. Diez Pardos, D. Domínguez Damiani,
G. Eckerlin, D. Eckstein, T. Eichhorn, A. Elwood, E. Eren, E. Gallo18, A.
Geiser, A. Grohsjean, M. Guthoff, M. Haranko, A. Harb, A. Jafari, N.Z.
Jomhari, H. Jung, A. Kasem17, M. Kasemann, H. Kaveh, J. Keaveney, C.
Kleinwort, J. Knolle, D. Krücker, W. Lange, T. Lenz, J. Lidrych, K. Lipka, W.
Lohmann19, R. Mankel, I.-A. Melzer-Pellmann, A.B. Meyer, M. Meyer, M.
Missiroli, J. Mnich, A. Mussgiller, V. Myronenko, D. Pérez Adán, S.K.
Pflitsch, D. Pitzl, A. Raspereza, A. Saibel, M. Savitskyi, V. Scheurer, P.
Schütze, C. Schwanenberger, R. Shevchenko, A. Singh, R.E. Sosa Ricardo, H.
Tholen, O. Turkot, A. Vagnerini, M. Van De Klundert, R. Walsh, Y. Wen, K.
Wichmann, C. Wissing, O. Zenaiev, R. Zlebcik University of Hamburg, Hamburg,
Germany
R. Aggleton, S. Bein, L. Benato, A. Benecke, T. Dreyer, A. Ebrahimi, F.
Feindt, A. Fröhlich, C. Garbers, 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, T. Lange, A. Malara, J. Multhaup,
C.E.N. Niemeyer, A. Reimers, O. Rieger, P. Schleper, S. Schumann, J. Schwandt,
J. Sonneveld, H. Stadie, G. Steinbrück, B. Vormwald, I. Zoi Karlsruher
Institut fuer Technologie, Karlsruhe, Germany
M. Akbiyik, M. Baselga, S. Baur, T. Berger, E. Butz, R. Caspart, T. Chwalek,
W. De Boer, A. Dierlamm, K. El Morabit, N. Faltermann, M. Giffels, A.
Gottmann, F. Hartmann16, C. Heidecker, U. Husemann, M.A. Iqbal, S. Kudella, S.
Maier, S. Mitra, M.U. Mozer, D. Müller, Th. Müller, M. Musich, A. Nürnberg, G.
Quast, K. Rabbertz, D. Schäfer, M. Schröder, I. Shvetsov, H.J. Simonis, R.
Ulrich, M. Wassmer, M. Weber, C. Wöhrmann, R. Wolf, S. Wozniewski Institute of
Nuclear and Particle Physics (INPP), NCSR Demokritos, Aghia Paraskevi, Greece
G. Anagnostou, P. Asenov, G. Daskalakis, T. Geralis, A. Kyriakis, D. Loukas,
G. Paspalaki, A. Stakia National and Kapodistrian University of Athens,
Athens, Greece
M. Diamantopoulou, G. Karathanasis, P. Kontaxakis, A. Manousakis-katsikakis,
A. Panagiotou, I. Papavergou, N. Saoulidou, K. Theofilatos, K. Vellidis, E.
Vourliotis National Technical University of Athens, Athens, Greece
G. Bakas, K. Kousouris, I. Papakrivopoulos, G. Tsipolitis, A. Zacharopoulou
University of Ioánnina, Ioánnina, Greece
I. Evangelou, C. Foudas, P. Gianneios, P. Katsoulis, P. Kokkas, S. Mallios, K.
Manitara, N. Manthos, I. Papadopoulos, J. Strologas, F.A. Triantis, D.
Tsitsonis MTA-ELTE Lendület CMS Particle and Nuclear Physics Group, Eötvös
Loránd University, Budapest, Hungary
M. Bartók20, R. Chudasama, M. Csanad, P. Major, K. Mandal, A. Mehta, G.
Pasztor, O. Surányi, G.I. Veres Wigner Research Centre for Physics, Budapest,
Hungary
G. Bencze, C. Hajdu, D. Horvath21, F. Sikler, V. Veszpremi, G.
Vesztergombi${}^{\textrm{\textdagger}}$ Institute of Nuclear Research ATOMKI,
Debrecen, Hungary
N. Beni, S. Czellar, J. Karancsi20, J. Molnar, Z. Szillasi Institute of
Physics, University of Debrecen, Debrecen, Hungary
P. Raics, D. Teyssier, Z.L. Trocsanyi, B. Ujvari Eszterhazy Karoly University,
Karoly Robert Campus, Gyongyos, Hungary
T. Csorgo, W.J. Metzger, F. Nemes, T. Novak 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. Bahinipati23, C. Kar, G. Kole, P. Mal, V.K. Muraleedharan Nair Bindhu, A.
Nayak24, D.K. Sahoo23, S.K. Swain Panjab University, Chandigarh, India
S. Bansal, S.B. Beri, V. Bhatnagar, S. Chauhan, N. Dhingra25, R. Gupta, A.
Kaur, M. Kaur, S. Kaur, P. Kumari, M. Lohan, M. Meena, 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, M.
Naimuddin, P. Priyanka, K. Ranjan, Aashaq Shah, R. Sharma Saha Institute of
Nuclear Physics, HBNI, Kolkata, India
R. Bhardwaj26, M. Bharti26, R. Bhattacharya, S. Bhattacharya, U. Bhawandeep26,
D. Bhowmik, S. Dutta, S. Ghosh, B. Gomber27, M. Maity28, K. Mondal, S. Nandan,
A. Purohit, P.K. Rout, G. Saha, S. Sarkar, M. Sharan, B. Singh26, S. Thakur26
Indian Institute of Technology Madras, Madras, India
P.K. Behera, S.C. Behera, P. Kalbhor, A. Muhammad, P.R. Pujahari, A. Sharma,
A.K. Sikdar Bhabha Atomic Research Centre, Mumbai, India
D. Dutta, V. Jha, D.K. Mishra, 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, RavindraKumar Verma Tata
Institute of Fundamental Research-B, Mumbai, India
S. Banerjee, S. Bhattacharya, S. Chatterjee, P. Das, M. Guchait, S. Karmakar,
S. Kumar, G. Majumder, K. Mazumdar, N. Sahoo, S. Sawant Indian Institute of
Science Education and Research (IISER), Pune, India
S. Dube, B. Kansal, A. Kapoor, K. Kothekar, S. Pandey, A. Rane, A. Rastogi, S.
Sharma Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
S. Chenarani, S.M. Etesami, M. Khakzad, M. Mohammadi Najafabadi, M. Naseri, F.
Rezaei Hosseinabadi 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, R. Alya,b,29, C. Calabriaa,b, A. Colaleoa, D. Creanzaa,c, L.
Cristellaa,b, N. De Filippisa,c, M. De Palmaa,b, A. Di Florioa,b, W.
Elmetenaweea,b, L. Fiorea, A. Gelmia,b, G. Iasellia,c, M. Incea,b, S.
Lezkia,b, G. Maggia,c, M. Maggia, J.A. Merlina, G. Minielloa,b, S. Mya,b, S.
Nuzzoa,b, A. Pompilia,b, G. Pugliesea,c, R. Radognaa, A. Ranieria, G.
Selvaggia,b, L. Silvestrisa, F.M. Simonea,b, R. Vendittia, P. Verwilligena
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,
C. Cioccaa, G. Codispotia,b, M. Cuffiania,b, G.M. Dallavallea, F. Fabbria, A.
Fanfania,b, E. Fontanesia,b, P. Giacomellia, C. Grandia, L. Guiduccia,b, F.
Iemmia,b, S. Lo Meoa,30, S. Marcellinia, G. Masettia, F.L. Navarriaa,b, A.
Perrottaa, F. Primaveraa,b, A.M. Rossia,b, T. Rovellia,b, G.P. Sirolia,b, N.
Tosia INFN Sezione di Catania a, Università di Catania b, Catania, Italy
S. Albergoa,b,31, S. Costaa,b, A. Di Mattiaa, R. Potenzaa,b, A. Tricomia,b,31,
C. Tuvea,b INFN Sezione di Firenze a, Università di Firenze b, Firenze, Italy
G. Barbaglia, A. Cassesea, R. Ceccarellia,b, V. Ciullia,b, C. Civininia, R.
D’Alessandroa,b, F. Fioria,c, E. Focardia,b, G. Latinoa,b, P. Lenzia,b, M.
Meschinia, S. Paolettia, G. Sguazzonia, L. Viliania INFN Laboratori Nazionali
di Frascati, Frascati, Italy
L. Benussi, S. Bianco, D. Piccolo INFN Sezione di Genova a, Università di
Genova b, Genova, Italy
M. Bozzoa,b, F. Ferroa, R. Mulargiaa,b, E. Robuttia, S. Tosia,b INFN Sezione
di Milano-Bicocca a, Università di Milano-Bicocca b, Milano, Italy
A. Benagliaa, A. Beschia,b, F. Brivioa,b, V. Cirioloa,b,16, M.E. Dinardoa,b,
P. Dinia, S. Gennaia, A. Ghezzia,b, P. Govonia,b, L. Guzzia,b, M. Malbertia,
S. Malvezzia, D. Menascea, F. Montia,b, L. Moronia, M. Paganonia,b, D.
Pedrinia, S. Ragazzia,b, T. Tabarelli de Fatisa,b, D. Valsecchia,b,16, 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, L. Layera,b, L. Listaa,b,
S. Meolaa,d,16, P. Paoluccia,16, B. Rossia, 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. Bragagnoloa,b, R.
Carlina,b, P. Checchiaa, P. De Castro Manzanoa, T. Dorigoa, U. Dossellia, F.
Gasparinia,b, U. Gasparinia,b, A. Gozzelinoa, S.Y. Hoha,b, M. Margonia,b, A.T.
Meneguzzoa,b, J. Pazzinia,b, M. Presillab, P. Ronchesea,b, R. Rossina,b, F.
Simonettoa,b, A. Tikoa, M. Tosia,b, M. Zanettia,b, P. Zottoa,b, A.
Zucchettaa,b, G. Zumerlea,b INFN Sezione di Pavia a, Università di Pavia b,
Pavia, Italy
A. Braghieria, D. Fiorinaa,b, P. Montagnaa,b, S.P. Rattia,b, V. Rea, M.
Ressegottia,b, C. Riccardia,b, P. Salvinia, I. Vaia, P. Vituloa,b INFN Sezione
di Perugia a, Università di Perugia b, Perugia, Italy
M. Biasinia,b, G.M. Bileia, 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, V. Bertacchia,c, L. Bianchinia, T.
Boccalia, R. Castaldia, M.A. Cioccia,b, R. Dell’Orsoa, S. Donatoa, 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, G. Rolandia,c, S. Roy
Chowdhurya,c, A. Scribanoa, P. Spagnoloa, R. Tenchinia, G. Tonellia,b, N.
Turinia, A. Venturia, P.G. Verdinia INFN Sezione di Roma a, Sapienza
Università di Roma b, Rome, Italy
F. Cavallaria, M. Cipriania,b, D. Del Rea,b, E. Di Marcoa, M. Diemoza, E.
Longoa,b, P. Meridiania, G. Organtinia,b, F. Pandolfia, R. Paramattia,b, C.
Quarantaa,b, S. Rahatloua,b, C. Rovellia, F. Santanastasioa,b, L. Soffia,b, R.
Tramontanoa,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, A. Belloraa,b, C. Biinoa, A. Cappatia,b, N. Cartigliaa, S.
Comettia, M. Costaa,b, R. Covarellia,b, N. Demariaa, J.R. González Fernándeza,
B. Kiania,b, F. Leggera, C. Mariottia, S. Masellia, E. Migliorea,b, V.
Monacoa,b, E. Monteila,b, M. Montenoa, M.M. Obertinoa,b, G. Ortonaa, L.
Pachera,b, N. Pastronea, M. Pelliccionia, G.L. Pinna Angionia,b, A. Romeroa,b,
M. Ruspaa,c, R. Salvaticoa,b, V. Solaa, A. Solanoa,b, D. Soldia,b, A.
Staianoa, D. Trocinoa,b 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
B. Kim, D.H. Kim, G.N. Kim, J. 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 Hanyang University, Seoul, Korea
B. Francois, T.J. Kim, J. Park Korea University, Seoul, Korea
S. Cho, S. Choi, Y. Go, S. Ha, B. Hong, K. Lee, K.S. Lee, J. Lim, J. Park,
S.K. Park, Y. Roh, J. Yoo Kyung Hee University, Department of Physics
J. Goh Sejong University, Seoul, Korea
H.S. Kim Seoul National University, Seoul, Korea
J. Almond, J.H. Bhyun, J. Choi, S. Jeon, J. Kim, J.S. Kim, H. Lee, K. Lee, S.
Lee, K. Nam, M. Oh, S.B. Oh, B.C. Radburn-Smith, U.K. Yang, H.D. Yoo, I. Yoon
University of Seoul, Seoul, Korea
D. Jeon, J.H. Kim, J.S.H. Lee, I.C. Park, I.J Watson Sungkyunkwan University,
Suwon, Korea
Y. Choi, C. Hwang, Y. Jeong, J. Lee, Y. Lee, I. Yu Riga Technical University,
Riga, Latvia
V. Veckalns32 Vilnius University, Vilnius, Lithuania
V. Dudenas, A. Juodagalvis, A. Rinkevicius, G. Tamulaitis, J. Vaitkus National
Centre for Particle Physics, Universiti Malaya, Kuala Lumpur, Malaysia
F. Mohamad Idris33, 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, L. Valencia Palomo
Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico
H. Castilla-Valdez, E. De La Cruz-Burelo, I. Heredia-De La Cruz34, R. Lopez-
Fernandez, A. Sanchez-Hernandez Universidad Iberoamericana, Mexico City,
Mexico
S. Carrillo Moreno, C. Oropeza Barrera, M. Ramirez-Garcia, 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 Montenegro, Podgorica, Montenegro
J. Mijuskovic2, N. Raicevic University of Auckland, Auckland, New Zealand
D. Krofcheck University of Canterbury, Christchurch, New Zealand
S. Bheesette, P.H. Butler, P. Lujan National Centre for Physics, Quaid-I-Azam
University, Islamabad, Pakistan
A. Ahmad, M. Ahmad, M.I.M. Awan, Q. Hassan, H.R. Hoorani, W.A. Khan, M.A.
Shah, M. Shoaib, M. Waqas AGH University of Science and Technology Faculty of
Computer Science, Electronics and Telecommunications, Krakow, Poland
V. Avati, L. Grzanka, M. Malawski National Centre for Nuclear Research,
Swierk, Poland
H. Bialkowska, M. Bluj, B. Boimska, M. Górski, M. Kazana, M. Szleper, P.
Zalewski Institute of Experimental Physics, Faculty of Physics, University of
Warsaw, Warsaw, Poland
K. Bunkowski, A. Byszuk35, K. Doroba, A. Kalinowski, M. Konecki, J.
Krolikowski, M. Olszewski, M. Walczak Laboratório de Instrumentação e Física
Experimental de Partículas, Lisboa, Portugal
M. Araujo, P. Bargassa, D. Bastos, A. Di Francesco, P. Faccioli, B. Galinhas,
M. Gallinaro, J. Hollar, N. Leonardo, T. Niknejad, J. Seixas, K. Shchelina, G.
Strong, O. Toldaiev, J. Varela Joint Institute for Nuclear Research, Dubna,
Russia
S. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, N. Gorbounov, I. Gorbunov,
A. Kamenev, V. Karjavine, I. Kashunin, V. Korenkov, A. Lanev, A. Malakhov, V.
Matveev36,37, V.V. Mitsyn, P. Moisenz, V. Palichik, V. Perelygin, S. Shmatov,
V. Trofimov, A. Zarubin Petersburg Nuclear Physics Institute, Gatchina (St.
Petersburg), Russia
L. Chtchipounov, V. Golovtcov, Y. Ivanov, V. Kim38, E. Kuznetsova39, P.
Levchenko, V. Murzin, V. Oreshkin, I. Smirnov, D. Sosnov, V. Sulimov, L.
Uvarov, 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, A. Nikitenko40, V. Popov, I.
Pozdnyakov, G. Safronov, A. Spiridonov, A. Stepennov, 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. Chadeeva41, P. Parygin, D. Philippov, E. Popova, V. Rusinov P.N. Lebedev
Physical Institute, Moscow, Russia
V. Andreev, M. Azarkin, I. Dremin, M. Kirakosyan, A. Terkulov Skobeltsyn
Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow,
Russia
A. Belyaev, E. Boos, A. Demiyanov, A. Ershov, A. Gribushin, O. Kodolova, V.
Korotkikh, I. Lokhtin, S. Obraztsov, S. Petrushanko, V. Savrin, A. Snigirev,
I. Vardanyan Novosibirsk State University (NSU), Novosibirsk, Russia
A. Barnyakov42, V. Blinov42, T. Dimova42, L. Kardapoltsev42, Y. Skovpen42
Institute for High Energy Physics of National Research Centre ‘Kurchatov
Institute’, Protvino, Russia
I. Azhgirey, I. Bayshev, S. Bitioukov, V. Kachanov, 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, A. Iuzhakov, V. Okhotnikov Tomsk State University, Tomsk, Russia
V. Borchsh, V. Ivanchenko, E. Tcherniaev University of Belgrade: Faculty of
Physics and VINCA Institute of Nuclear Sciences
P. Adzic43, P. Cirkovic, M. Dordevic, P. Milenovic, J. Milosevic, M.
Stojanovic Centro de Investigaciones Energéticas Medioambientales y
Tecnológicas (CIEMAT), Madrid, Spain
M. Aguilar-Benitez, J. Alcaraz Maestre, A. Álvarez Fernández, I. Bachiller, M.
Barrio Luna, CristinaF. Bedoya, J.A. Brochero Cifuentes, C.A. Carrillo
Montoya, M. Cepeda, M. Cerrada, N. Colino, B. De La Cruz, A. Delgado Peris,
J.P. Fernández Ramos, J. Flix, M.C. Fouz, O. Gonzalez Lopez, S. Goy Lopez,
J.M. Hernandez, M.I. Josa, D. Moran, Á. Navarro Tobar, A. Pérez-Calero
Yzquierdo, J. Puerta Pelayo, I. Redondo, L. Romero, S. Sánchez Navas, M.S.
Soares, A. Triossi, C. Willmott Universidad Autónoma de Madrid, Madrid, Spain
C. Albajar, J.F. de Trocóniz, R. Reyes-Almanza Universidad de Oviedo,
Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias
(ICTEA), Oviedo, Spain
B. Alvarez Gonzalez, J. Cuevas, C. Erice, J. Fernandez Menendez, S. Folgueras,
I. Gonzalez Caballero, E. Palencia Cortezon, C. Ramón Álvarez, V. Rodríguez
Bouza, S. Sanchez Cruz 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, G. Gomez, C. Martinez
Rivero, P. Martinez Ruiz del Arbol, F. Matorras, J. Piedra Gomez, C. Prieels,
F. Ricci-Tam, T. Rodrigo, A. Ruiz-Jimeno, L. Russo44, L. Scodellaro, I. Vila,
J.M. Vizan Garcia University of Colombo, Colombo, Sri Lanka
D.U.J. Sonnadara University of Ruhuna, Department of Physics, Matara, Sri
Lanka
W.G.D. Dharmaratna, N. Wickramage CERN, European Organization for Nuclear
Research, Geneva, Switzerland
T.K. Aarrestad, D. Abbaneo, B. Akgun, E. Auffray, G. Auzinger, J. Baechler, P.
Baillon, A.H. Ball, D. Barney, J. Bendavid, M. Bianco, A. Bocci, P. Bortignon,
E. Bossini, E. Brondolin, T. Camporesi, A. Caratelli, G. Cerminara, E. Chapon,
G. Cucciati, D. d’Enterria, A. Dabrowski, N. Daci, V. Daponte, A. David, O.
Davignon, A. De Roeck, M. Deile, R. Di Maria, M. Dobson, M. Dünser, N. Dupont,
A. Elliott-Peisert, N. Emriskova, F. Fallavollita45, D. Fasanella, S.
Fiorendi, G. Franzoni, J. Fulcher, W. Funk, S. Giani, D. Gigi, K. Gill, F.
Glege, L. Gouskos, M. Gruchala, M. Guilbaud, D. Gulhan, J. Hegeman, C.
Heidegger, Y. Iiyama, V. Innocente, T. James, P. Janot, O. Karacheban19, J.
Kaspar, J. Kieseler, M. Krammer1, N. Kratochwil, C. Lange, P. Lecoq, K. Long,
C. Lourenço, L. Malgeri, M. Mannelli, A. Massironi, F. Meijers, S. Mersi, E.
Meschi, F. Moortgat, M. Mulders, J. Ngadiuba, J. Niedziela, S. Nourbakhsh, S.
Orfanelli, L. Orsini, F. Pantaleo16, L. Pape, E. Perez, M. Peruzzi, A.
Petrilli, G. Petrucciani, A. Pfeiffer, M. Pierini, F.M. Pitters, D. Rabady, A.
Racz, M. Rieger, M. Rovere, H. Sakulin, J. Salfeld-Nebgen, S. Scarfi, C.
Schäfer, C. Schwick, M. Selvaggi, A. Sharma, P. Silva, W. Snoeys, P.
Sphicas46, J. Steggemann, S. Summers, V.R. Tavolaro, D. Treille, A. Tsirou,
G.P. Van Onsem, A. Vartak, M. Verzetti, K.A. Wozniak, W.D. Zeuner Paul
Scherrer Institut, Villigen, Switzerland
L. Caminada47, K. Deiters, W. Erdmann, R. Horisberger, Q. Ingram, H.C.
Kaestli, D. Kotlinski, U. Langenegger, T. Rohe ETH Zurich - Institute for
Particle Physics and Astrophysics (IPA), Zurich, Switzerland
M. Backhaus, P. Berger, N. Chernyavskaya, G. Dissertori, M. Dittmar, M.
Donegà, C. Dorfer, T.A. Gómez Espinosa, C. Grab, D. Hits, W. Lustermann, R.A.
Manzoni, M.T. Meinhard, F. Micheli, P. Musella, F. Nessi-Tedaldi, F. Pauss, V.
Perovic, G. Perrin, L. Perrozzi, S. Pigazzini, M.G. Ratti, M. Reichmann, C.
Reissel, T. Reitenspiess, B. Ristic, D. Ruini, D.A. Sanz Becerra, M.
Schönenberger, L. Shchutska, M.L. Vesterbacka Olsson, R. Wallny, D.H. Zhu
Universität Zürich, Zurich, Switzerland
C. Amsler48, C. Botta, D. Brzhechko, M.F. Canelli, A. De Cosa, R. Del Burgo,
B. Kilminster, S. Leontsinis, V.M. Mikuni, I. Neutelings, G. Rauco, P.
Robmann, K. Schweiger, Y. Takahashi, S. Wertz National Central University,
Chung-Li, Taiwan
C.M. Kuo, W. Lin, A. Roy, T. Sarkar28, S.S. Yu National Taiwan University
(NTU), Taipei, Taiwan
P. Chang, Y. Chao, K.F. Chen, P.H. Chen, W.-S. Hou, Y.y. Li, R.-S. Lu, E.
Paganis, A. Psallidas, A. Steen Chulalongkorn University, Faculty of Science,
Department of Physics, Bangkok, Thailand
B. Asavapibhop, C. Asawatangtrakuldee, N. Srimanobhas, N. Suwonjandee Çukurova
University, Physics Department, Science and Art Faculty, Adana, Turkey
A. Bat, F. Boran, A. Celik49, S. Damarseckin50, Z.S. Demiroglu, F. Dolek, C.
Dozen51, I. Dumanoglu52, G. Gokbulut, EmineGurpinar Guler53, Y. Guler, I.
Hos54, C. Isik, E.E. Kangal55, O. Kara, A. Kayis Topaksu, U. Kiminsu, G.
Onengut, K. Ozdemir56, S. Ozturk57, A.E. Simsek, U.G. Tok, S. Turkcapar, I.S.
Zorbakir, C. Zorbilmez Middle East Technical University, Physics Department,
Ankara, Turkey
B. Isildak58, G. Karapinar59, M. Yalvac60 Bogazici University, Istanbul,
Turkey
I.O. Atakisi, E. Gülmez, M. Kaya61, O. Kaya62, Ö. Özçelik, S. Tekten62, E.A.
Yetkin63 Istanbul Technical University, Istanbul, Turkey
A. Cakir, K. Cankocak52, Y. Komurcu, S. Sen64 Istanbul University, Istanbul,
Turkey
S. Cerci65, B. Kaynak, S. Ozkorucuklu, D. Sunar Cerci65 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
E. Bhal, S. Bologna, J.J. Brooke, D. Burns66, E. Clement, D. Cussans, H.
Flacher, J. Goldstein, G.P. Heath, H.F. Heath, L. Kreczko, B. Krikler, S.
Paramesvaran, T. Sakuma, S. Seif El Nasr-Storey, V.J. Smith, J. Taylor, A.
Titterton Rutherford Appleton Laboratory, Didcot, United Kingdom
K.W. Bell, A. Belyaev67, C. Brew, R.M. Brown, D.J.A. Cockerill, J.A. Coughlan,
K. Harder, S. Harper, J. Linacre, K. Manolopoulos, D.M. Newbold, E. Olaiya, D.
Petyt, T. Reis, T. Schuh, C.H. Shepherd-Themistocleous, A. Thea, I.R. Tomalin,
T. Williams Imperial College, London, United Kingdom
R. Bainbridge, P. Bloch, S. Bonomally, J. Borg, S. Breeze, O. Buchmuller, A.
Bundock, GurpreetSingh CHAHAL68, D. Colling, P. Dauncey, G. Davies, M. Della
Negra, P. Everaerts, G. Hall, G. Iles, M. Komm, L. Lyons, A.-M. Magnan, S.
Malik, A. Martelli, V. Milosevic, A. Morton, J. Nash69, V. Palladino, M.
Pesaresi, D.M. Raymond, A. Richards, A. Rose, E. Scott, C. Seez, A.
Shtipliyski, M. Stoye, T. Strebler, A. Tapper, K. Uchida, T. Virdee16, N.
Wardle, S.N. Webb, D. Winterbottom, A.G. Zecchinelli, S.C. Zenz Brunel
University, Uxbridge, United Kingdom
J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, C.K. Mackay, I.D. Reid, L.
Teodorescu, S. Zahid Baylor University, Waco, USA
A. Brinkerhoff, K. Call, B. Caraway, J. Dittmann, K. Hatakeyama, C. Madrid, B.
McMaster, N. Pastika, C. Smith Catholic University of America, Washington, DC,
USA
R. Bartek, A. Dominguez, R. Uniyal, A.M. Vargas Hernandez The University of
Alabama, Tuscaloosa, USA
A. Buccilli, S.I. Cooper, S.V. Gleyzer, C. Henderson, P. Rumerio, C. West
Boston University, Boston, USA
A. Albert, D. Arcaro, Z. Demiragli, D. Gastler, C. Richardson, J. Rohlf, D.
Sperka, D. Spitzbart, I. Suarez, L. Sulak, D. Zou Brown University,
Providence, USA
G. Benelli, B. Burkle, X. Coubez17, D. Cutts, Y.t. Duh, M. Hadley, U. Heintz,
J.M. Hogan70, K.H.M. Kwok, E. Laird, G. Landsberg, K.T. Lau, J. Lee, M.
Narain, S. Sagir71, R. Syarif, E. Usai, W.Y. Wong, D. Yu, W. Zhang University
of California, Davis, Davis, USA
R. Band, C. Brainerd, R. Breedon, M. Calderon De La Barca Sanchez, M. Chertok,
J. Conway, R. Conway, P.T. Cox, R. Erbacher, C. Flores, G. Funk, F. Jensen, W.
Ko${}^{\textrm{\textdagger}}$, O. Kukral, R. Lander, M. Mulhearn, D. Pellett,
J. Pilot, M. Shi, 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, W.A. Nash, S. Regnard, D. Saltzberg, C. Schnaible, B.
Stone, V. Valuev University of California, Riverside, Riverside, USA
K. Burt, Y. Chen, R. Clare, J.W. Gary, S.M.A. Ghiasi Shirazi, G. Hanson, G.
Karapostoli, O.R. Long, N. Manganelli, M. Olmedo Negrete, M.I. Paneva, W. Si,
S. Wimpenny, B.R. Yates, Y. Zhang University of California, San Diego, La
Jolla, USA
J.G. Branson, P. Chang, S. Cittolin, S. Cooperstein, N. Deelen, M. Derdzinski,
J. Duarte, R. Gerosa, D. Gilbert, B. Hashemi, D. Klein, V. Krutelyov, J.
Letts, M. Masciovecchio, S. May, S. Padhi, M. Pieri, V. Sharma, M. Tadel, F.
Würthwein, A. Yagil, G. Zevi Della Porta University of California, Santa
Barbara - Department of Physics, Santa Barbara, USA
N. Amin, R. Bhandari, C. Campagnari, M. Citron, V. Dutta, J. Incandela, B.
Marsh, H. Mei, A. Ovcharova, H. Qu, J. Richman, U. Sarica, D. Stuart, S. Wang
California Institute of Technology, Pasadena, USA
D. Anderson, A. Bornheim, O. Cerri, I. Dutta, J.M. Lawhorn, N. Lu, J. Mao,
H.B. Newman, T.Q. Nguyen, J. Pata, M. Spiropulu, J.R. Vlimant, S. Xie, Z.
Zhang, R.Y. Zhu Carnegie Mellon University, Pittsburgh, USA
J. Alison, 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, E. MacDonald, T. Mulholland, R. Patel, A. Perloff, K.
Stenson, K.A. Ulmer, S.R. Wagner Cornell University, Ithaca, USA
J. Alexander, Y. Cheng, J. Chu, A. Datta, A. Frankenthal, K. Mcdermott, J.R.
Patterson, D. Quach, A. Ryd, S.M. Tan, Z. Tao, J. Thom, 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, D. Berry, J. Berryhill, P.C. Bhat, K.
Burkett, J.N. Butler, A. Canepa, G.B. Cerati, H.W.K. Cheung, F. Chlebana, M.
Cremonesi, V.D. Elvira, J. Freeman, Z. Gecse, E. Gottschalk, L. Gray, D.
Green, S. Grünendahl, O. Gutsche, J. Hanlon, R.M. Harris, S. Hasegawa, R.
Heller, J. Hirschauer, B. Jayatilaka, S. Jindariani, M. Johnson, U. Joshi, T.
Klijnsma, B. Klima, M.J. Kortelainen, B. Kreis, S. Lammel, J. Lewis, 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, V.
Papadimitriou, K. Pedro, C. Pena72, F. Ravera, A. Reinsvold Hall, L. Ristori,
B. Schneider, E. Sexton-Kennedy, N. Smith, A. Soha, W.J. Spalding, L. Spiegel,
S. Stoynev, J. Strait, L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger, E.W.
Vaandering, C. Vernieri, R. Vidal, M. Wang, H.A. Weber, A. Woodard University
of Florida, Gainesville, USA
D. Acosta, P. Avery, D. Bourilkov, L. Cadamuro, V. Cherepanov, F. Errico, R.D.
Field, D. Guerrero, B.M. Joshi, M. Kim, J. Konigsberg, A. Korytov, K.H. Lo, K.
Matchev, N. Menendez, G. Mitselmakher, D. Rosenzweig, K. Shi, J. Wang, S.
Wang, X. Zuo Florida International University, Miami, USA
Y.R. Joshi Florida State University, Tallahassee, USA
T. Adams, A. Askew, S. Hagopian, V. Hagopian, K.F. Johnson, R. Khurana, T.
Kolberg, G. Martinez, T. Perry, H. Prosper, C. Schiber, R. Yohay, J. Zhang
Florida Institute of Technology, Melbourne, USA
M.M. Baarmand, M. Hohlmann, D. Noonan, M. Rahmani, M. Saunders, F. Yumiceva
University of Illinois at Chicago (UIC), Chicago, USA
M.R. Adams, L. Apanasevich, R.R. Betts, R. Cavanaugh, X. Chen, S. Dittmer, O.
Evdokimov, C.E. Gerber, D.A. Hangal, D.J. Hofman, V. Kumar, C. Mills, G. Oh,
T. Roy, M.B. Tonjes, N. Varelas, J. Viinikainen, H. Wang, X. Wang, Z. Wu The
University of Iowa, Iowa City, USA
M. Alhusseini, B. Bilki53, K. Dilsiz73, S. Durgut, R.P. Gandrajula, M.
Haytmyradov, V. Khristenko, O.K. Köseyan, J.-P. Merlo, A. Mestvirishvili74, A.
Moeller, J. Nachtman, H. Ogul75, Y. Onel, F. Ozok76, A. Penzo, C. Snyder, E.
Tiras, J. Wetzel, K. Yi77 Johns Hopkins University, Baltimore, USA
B. Blumenfeld, A. Cocoros, N. Eminizer, A.V. Gritsan, W.T. Hung, S. Kyriacou,
P. Maksimovic, C. Mantilla, J. Roskes, M. Swartz, T.Á. Vámi The University of
Kansas, Lawrence, USA
C. Baldenegro Barrera, P. Baringer, A. Bean, S. Boren, A. Bylinkin, T.
Isidori, S. Khalil, J. King, G. Krintiras, A. Kropivnitskaya, C. Lindsey, D.
Majumder, W. Mcbrayer, N. Minafra, M. Murray, C. Rogan, C. Royon, S. Sanders,
E. Schmitz, J.D. Tapia Takaki, Q. Wang, J. Williams, G. Wilson Kansas State
University, Manhattan, USA
S. Duric, A. Ivanov, K. Kaadze, D. Kim, Y. Maravin, D.R. Mendis, T. Mitchell,
A. Modak, A. Mohammadi 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, N.J. Hadley, S. Jabeen,
G.Y. Jeng, R.G. Kellogg, A.C. Mignerey, S. Nabili, M. Seidel, Y.H. Shin, A.
Skuja, S.C. Tonwar, L. Wang, K. Wong Massachusetts Institute of Technology,
Cambridge, USA
D. Abercrombie, B. Allen, R. Bi, S. Brandt, W. Busza, I.A. Cali, M. D’Alfonso,
G. Gomez Ceballos, M. Goncharov, P. Harris, D. Hsu, M. Hu, 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, D. Rankin, C. Roland, G. Roland, Z.
Shi, G.S.F. Stephans, K. Sumorok, K. Tatar, D. Velicanu, J. Wang, T.W. Wang,
B. Wyslouch University of Minnesota, Minneapolis, USA
R.M. Chatterjee, A. Evans, S. Guts${}^{\textrm{\textdagger}}$, P. Hansen, J.
Hiltbrand, Sh. Jain, Y. Kubota, Z. Lesko, J. Mans, M. Revering, R. Rusack, R.
Saradhy, N. Schroeder, N. Strobbe, M.A. Wadud University of Mississippi,
Oxford, USA
J.G. Acosta, S. Oliveros University of Nebraska-Lincoln, Lincoln, USA
K. Bloom, S. Chauhan, D.R. Claes, C. Fangmeier, L. Finco, F. Golf, R.
Kamalieddin, I. Kravchenko, J.E. Siado, G.R. Snow${}^{\textrm{\textdagger}}$,
B. Stieger, W. Tabb State University of New York at Buffalo, Buffalo, USA
G. Agarwal, C. Harrington, I. Iashvili, A. Kharchilava, C. McLean, D. Nguyen,
A. Parker, J. Pekkanen, S. Rappoccio, B. Roozbahani Northeastern University,
Boston, USA
G. Alverson, E. Barberis, C. Freer, Y. Haddad, A. Hortiangtham, G. Madigan, B.
Marzocchi, D.M. Morse, T. Orimoto, L. Skinnari, A. Tishelman-Charny, T.
Wamorkar, B. Wang, A. Wisecarver, D. Wood Northwestern University, Evanston,
USA
S. Bhattacharya, J. Bueghly, G. Fedi, A. Gilbert, T. Gunter, K.A. Hahn, N.
Odell, M.H. Schmitt, K. Sung, M. Velasco University of Notre Dame, Notre Dame,
USA
R. Bucci, N. Dev, R. Goldouzian, M. Hildreth, K. Hurtado Anampa, C. Jessop,
D.J. Karmgard, K. Lannon, W. Li, N. Loukas, N. Marinelli, I. Mcalister, F.
Meng, Y. Musienko36, R. Ruchti, P. Siddireddy, G. Smith, S. Taroni, M. Wayne,
A. Wightman, M. Wolf The Ohio State University, Columbus, USA
J. Alimena, B. Bylsma, L.S. Durkin, B. Francis, C. Hill, W. Ji, A. Lefeld,
T.Y. Ling, B.L. Winer Princeton University, Princeton, USA
G. Dezoort, P. Elmer, J. Hardenbrook, N. Haubrich, S. Higginbotham, A.
Kalogeropoulos, S. Kwan, D. Lange, M.T. Lucchini, J. Luo, D. Marlow, K. Mei,
I. Ojalvo, J. Olsen, C. Palmer, P. Piroué, D. Stickland, C. Tully University
of Puerto Rico, Mayaguez, USA
S. Malik, S. Norberg Purdue University, West Lafayette, USA
A. Barker, V.E. Barnes, R. Chawla, S. Das, L. Gutay, M. Jones, A.W. Jung, B.
Mahakud, D.H. Miller, G. Negro, N. Neumeister, C.C. Peng, S. Piperov, H. Qiu,
J.F. Schulte, N. Trevisani, F. Wang, R. Xiao, W. Xie Purdue University
Northwest, Hammond, USA
T. Cheng, J. Dolen, N. Parashar Rice University, Houston, USA
A. Baty, U. Behrens, S. Dildick, K.M. Ecklund, S. Freed, F.J.M. Geurts, M.
Kilpatrick, Arun Kumar, W. Li, B.P. Padley, R. Redjimi, J. Roberts, J. Rorie,
W. Shi, A.G. Stahl Leiton, Z. Tu, A. Zhang University of Rochester, Rochester,
USA
A. Bodek, P. de Barbaro, R. Demina, J.L. Dulemba, C. Fallon, T. Ferbel, M.
Galanti, A. Garcia-Bellido, O. Hindrichs, A. Khukhunaishvili, E. Ranken, R.
Taus Rutgers, The State University of New Jersey, Piscataway, USA
B. Chiarito, J.P. Chou, A. Gandrakota, Y. Gershtein, E. Halkiadakis, A. Hart,
M. Heindl, E. Hughes, S. Kaplan, I. Laflotte, A. Lath, R. Montalvo, K. Nash,
M. Osherson, S. Salur, S. Schnetzer, S. Somalwar, R. Stone, S. Thomas
University of Tennessee, Knoxville, USA
H. Acharya, A.G. Delannoy, S. Spanier Texas A&M University, College Station,
USA
O. Bouhali78, M. Dalchenko, M. De Mattia, A. Delgado, R. Eusebi, J. Gilmore,
T. Huang, T. Kamon79, H. Kim, S. Luo, S. Malhotra, D. Marley, R. Mueller, D.
Overton, L. Perniè, D. Rathjens, A. Safonov Texas Tech University, Lubbock,
USA
N. Akchurin, J. Damgov, F. De Guio, V. Hegde, S. Kunori, K. Lamichhane, S.W.
Lee, T. Mengke, S. Muthumuni, T. Peltola, S. Undleeb, I. Volobouev, Z. Wang,
A. Whitbeck Vanderbilt University, Nashville, USA
S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, A. Melo, H. Ni, K.
Padeken, F. Romeo, P. Sheldon, S. Tuo, J. Velkovska, M. Verweij University of
Virginia, Charlottesville, USA
M.W. Arenton, P. Barria, B. Cox, G. Cummings, J. Hakala, R. Hirosky, M. Joyce,
A. Ledovskoy, C. Neu, B. Tannenwald, Y. Wang, E. Wolfe, F. Xia Wayne State
University, Detroit, USA
R. Harr, P.E. Karchin, N. Poudyal, J. Sturdy, P. Thapa University of Wisconsin
- Madison, Madison, WI, USA
K. Black, T. Bose, J. Buchanan, C. Caillol, D. Carlsmith, S. Dasu, I. De
Bruyn, L. Dodd, C. Galloni, H. He, M. Herndon, A. Hervé, U. Hussain, A.
Lanaro, A. Loeliger, R. Loveless, J. Madhusudanan Sreekala, A. Mallampalli, D.
Pinna, T. Ruggles, A. Savin, V. Sharma, W.H. Smith, D. Teague, S. Trembath-
reichert †: 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 UFMS, Nova Andradina, Brazil
6: Also at Universidade Federal de Pelotas, Pelotas, Brazil
7: Also at Université Libre de Bruxelles, Bruxelles, Belgium
8: Also at University of Chinese Academy of Sciences, Beijing, China
9: Also at Institute for Theoretical and Experimental Physics named by A.I.
Alikhanov of NRC ‘Kurchatov Institute’, Moscow, Russia
10: Also at Joint Institute for Nuclear Research, Dubna, Russia
11: Also at Fayoum University, El-Fayoum, Egypt
12: Now at British University in Egypt, Cairo, Egypt
13: Also at Purdue University, West Lafayette, USA
14: Also at Université de Haute Alsace, Mulhouse, France
15: Also at Erzincan Binali Yildirim University, Erzincan, Turkey
16: Also at CERN, European Organization for Nuclear Research, Geneva,
Switzerland
17: Also at RWTH Aachen University, III. Physikalisches Institut A, Aachen,
Germany
18: Also at University of Hamburg, Hamburg, Germany
19: Also at Brandenburg University of Technology, Cottbus, Germany
20: Also at Institute of Physics, University of Debrecen, Debrecen, Hungary,
Debrecen, Hungary
21: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary
22: Also at MTA-ELTE Lendület CMS Particle and Nuclear Physics Group, Eötvös
Loránd University, Budapest, Hungary, Budapest, Hungary
23: Also at IIT Bhubaneswar, Bhubaneswar, India, Bhubaneswar, India
24: Also at Institute of Physics, Bhubaneswar, India
25: Also at G.H.G. Khalsa College, Punjab, India
26: Also at Shoolini University, Solan, India
27: Also at University of Hyderabad, Hyderabad, India
28: Also at University of Visva-Bharati, Santiniketan, India
29: Now at INFN Sezione di Bari a, Università di Bari b, Politecnico di Bari
c, Bari, Italy
30: Also at Italian National Agency for New Technologies, Energy and
Sustainable Economic Development, Bologna, Italy
31: Also at Centro Siciliano di Fisica Nucleare e di Struttura Della Materia,
Catania, Italy
32: Also at Riga Technical University, Riga, Latvia, Riga, Latvia
33: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia
34: Also at Consejo Nacional de Ciencia y Tecnología, Mexico City, Mexico
35: Also at Warsaw University of Technology, Institute of Electronic Systems,
Warsaw, Poland
36: Also at Institute for Nuclear Research, Moscow, Russia
37: Now at National Research Nuclear University ’Moscow Engineering Physics
Institute’ (MEPhI), Moscow, Russia
38: Also at St. Petersburg State Polytechnical University, St. Petersburg,
Russia
39: Also at University of Florida, Gainesville, USA
40: Also at Imperial College, London, United Kingdom
41: Also at P.N. Lebedev Physical Institute, Moscow, Russia
42: Also at Budker Institute of Nuclear Physics, Novosibirsk, Russia
43: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia
44: Also at Università degli Studi di Siena, Siena, Italy
45: Also at INFN Sezione di Pavia a, Università di Pavia b, Pavia, Italy,
Pavia, Italy
46: Also at National and Kapodistrian University of Athens, Athens, Greece
47: Also at Universität Zürich, Zurich, Switzerland
48: Also at Stefan Meyer Institute for Subatomic Physics, Vienna, Austria,
Vienna, Austria
49: Also at Burdur Mehmet Akif Ersoy University, BURDUR, Turkey
50: Also at Şırnak University, Sirnak, Turkey
51: Also at Department of Physics, Tsinghua University, Beijing, China,
Beijing, China
52: Also at Near East University, Research Center of Experimental Health
Science, Nicosia, Turkey
53: Also at Beykent University, Istanbul, Turkey, Istanbul, Turkey
54: Also at Istanbul Aydin University, Application and Research Center for
Advanced Studies (App. & Res. Cent. for Advanced Studies), Istanbul, Turkey
55: Also at Mersin University, Mersin, Turkey
56: Also at Piri Reis University, Istanbul, Turkey
57: Also at Gaziosmanpasa University, Tokat, Turkey
58: Also at Ozyegin University, Istanbul, Turkey
59: Also at Izmir Institute of Technology, Izmir, Turkey
60: Also at Bozok Universitetesi Rektörlügü, Yozgat, Turkey
61: Also at Marmara University, Istanbul, Turkey
62: Also at Kafkas University, Kars, Turkey
63: Also at Istanbul Bilgi University, Istanbul, Turkey
64: Also at Hacettepe University, Ankara, Turkey
65: Also at Adiyaman University, Adiyaman, Turkey
66: Also at Vrije Universiteit Brussel, Brussel, Belgium
67: Also at School of Physics and Astronomy, University of Southampton,
Southampton, United Kingdom
68: Also at IPPP Durham University, Durham, United Kingdom
69: Also at Monash University, Faculty of Science, Clayton, Australia
70: Also at Bethel University, St. Paul, Minneapolis, USA, St. Paul, USA
71: Also at Karamanoğlu Mehmetbey University, Karaman, Turkey
72: Also at California Institute of Technology, Pasadena, USA
73: Also at Bingol University, Bingol, Turkey
74: Also at Georgian Technical University, Tbilisi, Georgia
75: Also at Sinop University, Sinop, Turkey
76: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey
77: Also at Nanjing Normal University Department of Physics, Nanjing, China
78: Also at Texas A&M University at Qatar, Doha, Qatar
79: Also at Kyungpook National University, Daegu, Korea, Daegu, Korea