EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN) CERN-PH-EP/2015-210 2015/09/13 CMS-FSQ-13-006 Measurement of the inelastic cross section in proton-lead collisions at √ s NN = 5.02 TeV The CMS Collaboration * Abstract The inelastic hadronic cross section in proton-lead collisions at a centre-of-mass en- ergy per nucleon pair of 5.02TeV is measured with the CMS detector at the LHC. The data sample, corresponding to an integrated luminosity of L = 12.6 ± 0.4 nb -1 , has been collected with an unbiased trigger for inclusive particle production. The cross section is obtained from the measured number of proton-lead collisions with hadronic activity produced in the pseudorapidity ranges 3 < η < 5 and/or -5 < η < -3, corrected for photon-induced contributions, experimental accep- tance, and other instrumental effects. The inelastic cross section is measured to be σ inel (pPb)= 2061 ± 3 (stat) ± 34 (syst) ± 72 (lumi) mb. Various Monte Carlo genera- tors, commonly used in heavy ion and cosmic ray physics, are found to reproduce the data within uncertainties. The value of σ inel (pPb) is compatible with that expected from the proton-proton cross section at 5.02TeV scaled up within a simple Glauber approach to account for multiple scatterings in the lead nucleus, indicating that fur- ther net nuclear corrections are small. Submitted to Physics Letters B c 2015 CERN for the benefit of the CMS Collaboration. CC-BY-3.0 license * See Appendix A for the list of collaboration members arXiv:submit/1350852 [hep-ex] 13 Sep 2015
Transcript
EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN)
CERN-PH-EP/2015-2102015/09/13
CMS-FSQ-13-006
Measurement of the inelastic cross section in proton-leadcollisions at √sNN = 5.02 TeV
The CMS Collaboration∗
Abstract
The inelastic hadronic cross section in proton-lead collisions at a centre-of-mass en-ergy per nucleon pair of 5.02 TeV is measured with the CMS detector at the LHC.The data sample, corresponding to an integrated luminosity of L = 12.6± 0.4 nb−1,has been collected with an unbiased trigger for inclusive particle production. Thecross section is obtained from the measured number of proton-lead collisions withhadronic activity produced in the pseudorapidity ranges 3 < η < 5 and/or−5 < η < −3, corrected for photon-induced contributions, experimental accep-tance, and other instrumental effects. The inelastic cross section is measured to beσinel(pPb) = 2061± 3 (stat)± 34 (syst)± 72 (lumi) mb. Various Monte Carlo genera-tors, commonly used in heavy ion and cosmic ray physics, are found to reproduce thedata within uncertainties. The value of σinel(pPb) is compatible with that expectedfrom the proton-proton cross section at 5.02 TeV scaled up within a simple Glauberapproach to account for multiple scatterings in the lead nucleus, indicating that fur-ther net nuclear corrections are small.
1 IntroductionThe measurement of the inelastic cross section in proton-lead collisions, σinel(pPb), at a centre-of-mass energy per nucleon pair of 5.02 TeV performed by the CMS experiment at the CERNLHC is presented. The inelastic cross section (also called “particle-production” [1] or “absorp-tion” [2] cross section in previous studies) is defined to include all hadronic events, includingcontributions from diffractive processes, except those from the quasi-elastic excitation of thelead nucleus—estimated to amount to about 100 mb for the pPb system [3]. Inelastic electro-magnetic (photon-induced) collisions are also excluded from the measurement.
While being one of the most inclusive observables in hadronic collisions, the inclusive inelasticcross section is one of the least theoretically accessible quantities, as it cannot be determinedfrom first-principles calculations of the theory of the strong interaction, quantum chromody-namics. In proton-proton (pp) and nucleus-nucleus collisions at the LHC, particles producedin hadronic interactions come mostly from the hadronisation of quarks and gluons, either pro-duced in semi-hard scatterings (“minijets”) [4] or emitted at very forward rapidities from ”spec-tator” partons, as well as from soft diffractive processes in ”peripheral” interactions. From themeasured inelastic proton-proton (or nucleon-nucleon) cross section at a given collision en-ergy, one can theoretically derive the corresponding proton-nucleus and nucleus-nucleus crosssections by means of Glauber [5, 6] or Gribov–Regge [7] multiple-scattering approaches thattake into account the known transverse matter profile of nuclei. Key quantities for the exper-imental comparison between nucleus-nucleus and pp collisions—such as the nuclear overlapfunction, the number of nucleon-nucleon collisions and of participant nucleons [8, 9]—are alsocommonly computed through such approaches. Validating the Glauber and Gribov-Regge pre-dictions with proton-nucleus collisions at LHC energies has important implications beyondcollider physics. Such approaches constitute crucial ingredients in the Monte Carlo modellingof cosmic ray air showers at the highest energies [10], for which the inelastic cross sectionsmeasured in the laboratory must be extrapolated over a wide energy range. In fact, the inelas-tic proton-air (mostly proton-nitrogen and proton-oxygen) cross section introduces one of thelargest uncertainties for air shower simulations [11, 12].
The Glauber multiple-collision model, based on the eikonal limit (i.e. straight-line trajectoriesof the colliding nucleons), is the simplest and most economical approach often used to deriveinclusive proton-nucleus quantities from the pp cross sections and, vice versa, to obtain ppcross sections from the cosmic ray measurements [13]. However, some of the approximationsapplied in the model—foremost the absence of short-range nucleon correlations [14] and ofinelastic screening [15]—impact the computed cross section values. This is observed for fixed-target proton-carbon data [16–20] and estimated for collider [21, 22] as well as ultra-high cosmicray [13] energies, where corrections to the proton-air cross section of the order of 10% have beenobtained. Short-range correlations increase the number of nucleon-nucleon collisions at smallimpact parameters yielding a larger nucleus-nucleus cross section. On the other hand, screen-ing affects the number of nucleons that are diffractively excited in the multiple collisions butrevert back to their ground state before the scattering process is completed, thereby reducingthe nuclear cross section. Different implementations of such effects exist in the current hadronicinteraction models [15, 23–29]. A measurement of σinel in pPb collisions at the LHC can test ifthe precision of the standard Glauber calculation is sufficient, and at which energies correctionsto the Glauber approach may become relevant.
2 3 Event selection and analysis
2 Experimental setup and Monte Carlo simulationsThe measurement presented here is based on pPb data taken with the CMS experiment at theLHC at the beginning of 2013. A detailed description of the apparatus can be found in [30]. Themain detector used in this analysis is the hadron forward (HF) calorimeter that covers the pseu-dorapidity interval 3 < |η| < 5. The calorimeter is composed of quartz fibres in a steel matrixwith a 0.175×0.175 segmentation in the azimuthal angle φ (in radians) and pseudorapidity η.The quartz fibres pick up the Cherenkov light produced by the charged component of showers.This light is then measured by photodetector tubes. The hadronic and electromagnetic signalsof each segment, as derived from fibres of two different lengths, are combined to form a towersignal.
The data used in this analysis comprise an integrated luminosity of L = 12.6± 0.4 nb−1. Thisdataset combines the integrated luminosities of the two possible directions of the proton andlead beams: 5.0± 0.2 nb−1 and 7.6± 0.3 nb−1, for the proton beam going respectively in theclockwise (negative η) and anticlockwise (positive η) direction. The events are collected usingan unbiased trigger, only requiring the presence of both beams in the interaction point, asdetermined by the “Beam Pickup Timing for the eXperiments” (BPTX) devices. Detector noiseis studied with events that are randomly read out in the absence of both beams in the detector.The integrated luminosity is determined with a van der Meer scan [31] for both beam directionsindependently, with an uncertainty of 3.5% [32].
A Monte Carlo event simulation based on a GEANT4 detector description [33] is used to modelthe experimental response and derive the reconstruction efficiencies. Different event genera-tors are used to simulate hadronic proton-nucleus collisions. Three models are based on theGribov-Regge formalism: DPMJET 3.06 [34], EPOS-LHC [25], and QGSJETII–04 [26]; and a fourthone is based on a minijet+Glauber approach: HIJING 1.383 [35]. In addition, particle productionfrom electromagnetic interactions in “ultraperipheral” collisions, at impact parameters largerthan the sum of proton and lead radii, needs to be taken into account [36]. Given the large Pbion charge, and the associated large ”equivalent photon flux” of its electromagnetic field [36],inelastic photon-proton (γp) collisions result in a non-negligible particle production contri-bution. Pure photon-photon interactions, mostly producing exclusive electron-positron pairs,and photon-nucleus interactions (where the photon emitted from the proton collides with thePb ion) have orders-of-magnitude smaller visible cross sections and are neglected. Photon-proton processes are generated with the STARLIGHT programme [37] combined either withDPMJET 3.05 or PYTHIA 6.4.26 [38].
3 Event selection and analysisIn this analysis three types of cross sections are measured: (i) σobs after removal of noiseand pileup, (ii) σvis after further removal of electromagnetic contributions and translation intoa hadron-level quantity, and (iii) σinel including the final extrapolation to the total inelastichadronic cross section. Two different approaches are used to determine the number of inelasticevents: (1) a single-arm event selection that requires a calorimetric energy signal above a giventhreshold in the HF detector either at positive or negative pseudorapidities, and (2) a double-arm event selection that requires a signal above threshold in both HF detectors. The advantageof using these two event selections is to exploit very different sensitivities to diffractive andγp events as well as to detector noise. Denoting by EHF+ (EHF-) the highest energy measuredin an HF tower at positive (negative) pseudorapidity, an event is tagged as a candidate for an
3
inelastic collision if it has a value of
EHF =
{max(EHF+, EHF-) for single-arm selectionmin(EHF+, EHF-) for double-arm selection
Figure 1: Distribution of the energy deposited in the HF calorimeter (EHF) for the single-arm(left) and double-arm (right) event selections, for a data sample corresponding to 1.31 nb−1
recorded with an unbiased trigger. The contribution from noise is obtained from a random trig-ger normalised to the same number of triggers as that in the collision data. The average num-ber of γp processes simulated with STARLIGHT+DPMJET and STARLIGHT+PYTHIA is treated asbackground and stacked on top. Four hadronic interaction models (EPOS, DPMJET, HIJING, andQGSJETII) are overlaid and normalised to the number of data events with EHF > 10 GeV, wherethe contribution from the background is small. The vertical line represents the threshold energyof 8 GeV (4 GeV) for the single-arm (double-arm) selection used in this analysis.
The observed distribution of EHF is well reproduced by the combined hadronic inelastic, photon-proton, and detector noise contributions as shown in the left (right) panel of Fig. 1 for the single-arm (double-arm) selection. The size of the various contributions to the HF energy depositionis determined from data and simulations. The signal is identified as that coming from hadroniccollisions whereas the backgrounds arise from electromagnetic (em) photon-proton interac-tions and detector noise. The expected number of γp collisions is Nem = femσemL, where femis the fraction of simulated photon-proton events passing the selection and σem is the predictedSTARLIGHT cross section. The number of misidentified events produced by electronic noise inthe detector is Nnoise = N fnoise, where fnoise is the fraction of events read out randomly in theabsence of beams that pass the selection criteria, and N is the number of events recorded withthe unbiased trigger. The estimate of Nnoise includes Nobs+noise = Nobs fnoise events that containalso an observed inelastic collision, where Nobs is the number of observed inelastic events. Thedouble-counted events are explicitly subtracted from Nnoise. The uncertainty on Nnoise is de-rived from variations in different data-taking periods. The background induced by beam-gascollisions is found to be negligible deduced from the fraction of events selected with the triggerindicating the presence of a single beam in the interaction point.
Of the number of inelastic hadronic collisions, Ninel, the ones that are observed by the de-tector and pass the event selection are defined as Nhad. The purity of the event selection is
4 3 Event selection and analysis
Nhad/ (Nhad + Nem + Nnoise), and the acceptance is given by the ratio εacc = Nhad/Ninel. Boththe purity and the acceptance depend on the energy threshold used for the selection. Higherpurity is achieved for the double-arm selection, since photon-proton interactions lead to a typ-ical final state where most of the secondary products are asymmetrically emitted towards thedirection of the proton beam. Noise events are also suppressed by the coincidence requirement.The acceptance is in general smaller for the double-arm selection due to the smaller chance ofselecting diffractive events characterised by large rapidity gaps devoid of activity in one orboth HF sides.
The dependence of εacc on the HF tower energy threshold is shown in Fig. 2. For the single-armselection the working point is chosen to be EHF > 8 GeV, which is simultaneously optimisedfor 93–94% acceptance and purity. The double-arm selection uses EHF > 4 GeV yielding a99% purity and 91% acceptance. The value εacc for a specific EHF threshold is determined by
Purity0.9 1
acc
∈A
ccep
tanc
e
0.9
1
CMS = 5.02 TeVNNspPb,
Single-arm selection
Double-arm selection
8 GeV6 GeV
10 GeV
4 GeV3 GeV
5 GeV
Figure 2: Acceptance versus purity of the two event selections, as derived from the EPOS andQGSJETII generators. The symbols indicate different values of the EHF thresholds. The chosenthresholds are marked with squares.
averaging over the results of the EPOS and QGSJETII models. The results of HIJING and DPMJET,which do not include nuclear effects for diffraction, are not considered for this purpose.
The uncertainties on the εacc and Nem values are estimated from the maximum absolute differ-ences obtained from the results of different event generators, averaged over a wide EHF inter-val between 2 and 10 GeV. The uncertainties on εacc are 0.05 (0.014) and of Nem/L are 11 mb(0.05 mb) for the single-arm (double-arm) event selections.
In this analysis no vertex reconstruction is performed and the impact of contributions from ad-ditional pileup (PU) collisions recorded in any given event is consistently evaluated with theHF detector. The number of simultaneous collisions is Poisson-distributed with an expectationvalue corresponding to the interaction probability λ. If one collision is selected with probabil-ity εacc, then i simultaneous collisions are selected with probability Pi ≈ 1− (1− εacc)i. The
5
number of collisions is thus corrected using the factor fPU = εaccλ/∞∑
i=1Pi Poisson(i; λ). The in-
teraction probability λ is calculated recursively from the ratio of the number of inelastic eventsto the number of unbiased triggers. The pileup correction increases the measured cross sectionby 2% for both event selections, and introduces an uncertainty on the final pPb cross sectionthat is smaller than 0.1%.
To facilitate the direct comparison of the results to model predictions, detector level quanti-ties, such as EHF, are translated to hadron-level quantities. For this purpose, pHF is definedequivalently to Eq. (1) but replacing EHF by the largest absolute value among the momenta, |~p|,of all generated final-state particles (with lifetimes above 1 cm/c), within the pseudorapidityintervals of the HF calorimeters (3 < |η| < 5), excluding muons and neutrinos. A correctionfactor cvis, obtained from simulations, is used to translate the measured cross section into ahadron-level quantity, defined by the ratio of the number of visible events, which fulfil a givenrequirement on pHF, to the number of observed events, which pass the selection on EHF. Thus,cvis is larger than unity for requiring pHF > 0, but will approach zero for very high thresholds.The threshold can be chosen freely, and for the present analysis the requirement on the minimalvalue of pHF is chosen such that the fractions of events passing this selection and passing thaton EHF are equal. The factor cvis then becomes equal to unity and has no numerical effect on thecentral value of the derived cross section. This procedure leads to the choice of selecting eventsthat fulfil the requirement pHF > 21.3 GeV/c (11.3 GeV/c) for the single-arm (double-arm) anal-ysis. For the chosen thresholds, the mean of the cvis values of all four hadronic interactionmodels is unity and the slight dependence on models is taken into account as a systematicuncertainty on cvis equal to the standard deviation of the four values.
The values of the acceptance, backgrounds, and correction factors are summarised in Table 1.
Table 1: Central values and uncertainties for the two event selections for noise cross sectioncontribution (Nnoise/L) and the fraction of noise events ( fnoise) as derived from data. Addition-ally, the quantities acceptance (εacc), electromagnetic cross section contribution (Nem/L), andhadron-level correction factor (cvis) as derived from simulations are listed.
The number of observed inelastic events, Nobs, is derived from the number of events passingthe event selection, Nsel, and is corrected for noise (Nnoise) double counting (Nobs+noise), andpileup ( fPU) corrections. Dividing this number by the integrated luminosity yields the observedcross section:
σobs =Nobs
L = (Nsel − Nnoise + Nobs+noise)fPU
L . (2)
Using the relation Nobs+noise = Nobs fnoise one obtains
σobs =1L
Nsel − Nnoise
1/ fPU − fnoise. (3)
The visible cross section for hadronic collisions is derived by subtracting the photon-protoncontamination and applying the correction factor cvis. Its numerical value is, by definition,equal to the part of the observed cross section related to hadronic collisions:
σvis =1L
Nsel − Nnoise − Nem
1/ fPU − fnoisecvis. (4)
6 3 Event selection and analysis
The inelastic cross section is obtained by correcting for the limited detector acceptance (εacc):
σinel =1L
Nsel − Nnoise − Nem
1/ fPU − fnoise
1εacc
. (5)
The ratio of the visible hadronic cross section obtained with the single-arm selection to the oneobtained with the double-arm selection is sensitive to the fraction of diffractive pPb events. Itis found that the measured value of this ratio allows the EPOS diffractive cross section to bescaled up by no more than 1.13 or down by no less than 0.88 from its default value, in orderto be compatible within 2 standard deviations of the data, while for QGSJETII those limits are1.20 and 0.84. This propagates into an εacc(σdiff) uncertainty on σinel, conservatively assumedto be symmetric, of 0.8% (1.1%). For this and the following uncertainties, the first number isrelated to the single-arm selection and the bracketed one to the double-arm selection. Themodel-dependence of the acceptance corrections results in an uncertainty for εacc(models) of0.5% (1.6%) for the two selections, respectively.
Since less than half of the diffractive events, mostly with a high-mass diffractive system, passthe hadron-level selection, the uncertainty on cvis is smaller than that on εacc. The 1 standarddeviation differences found among the four hadronic interaction models on the hadron-levelcorrection, cvis, propagate into uncertainties on σvis of 0.4% (0.2%) for the single-arm (double-arm) selection. The subtraction of photon-proton events (with the Nem uncertainty shown inTable 1), results in an uncertainty of 0.6% (<0.1%) on σinel and σvis. The uncertainty on Nnoisepropagates into a 1.3% (0.2%) uncertainty in the final cross sections. The effect on the eventselection of the radiation damage in the HF fibres is assessed by rescaling the signals of thesimulated HF response to match data in segments of pseudorapidity. The rescaling factors arecalculated using the average response produced by EPOS, HIJING, and QGSJETII. These scalingfactors are found to be consistent with the observed radiation damage of HF and range from 1to 0.67, depending on pseudorapidity. The systematic uncertainty induced on the cross sectionby this approach is estimated by repeating the measurement without the radiation damagecorrection, which introduces an effect of 1.7% (0.8%) on the cross section. The simulated signalscontain the underlying contribution from noise. To test the importance of noise on the eventselection the noise measured from data was added to the simulated signals. As a further checkof the HF tower energy resolution, the cross sections are computed by increasing the selectionthresholds to EHF > 10 GeV (5 GeV). To account for both effects, a systematic uncertainty onthe cross section of 0.6% (0.4%) is added.
Table 2: List of the systematic uncertainties, propagated into the final pPb cross sections, forthe two event selections.
All the different sources of uncertainty of the measurement are listed in Table 2 for the single-arm and double-arm event selections. The three derived cross sections have different system-
7
atic uncertainties since not all contributions are relevant to each of them. For σinel, all uncer-tainties but the one due to the hadron-level correction contribute. The total uncorrelated sys-tematic uncertainty is therefore 2.5% (2.2%) for the single-arm (double-arm) selection. For σvis,the dominant uncertainty is due to the hadron-level correction instead of the correction for εacc.The value of the uncertainty is therefore reduced to 2.3% (0.9%). The uncertainties for detectorsimulation and photon-proton correction do not contribute to σobs and, hence, its uncertaintybecomes 1.4% (0.5%). For all cross sections, a (dominant) integrated luminosity uncertainty of3.5% is added.
4 Results and summaryThe measured cross sections for both event selections are listed in Table 3, compared to the pre-dictions of the hadronic interaction models DPMJET, EPOS, and QGSJETII. Due to the differentacceptance, the extrapolations from the hadron-level to the inelastic cross section are of dif-ferent magnitude, but the models reproduce well the approximately 65 mb difference betweenthe two selections. The values of the inelastic cross sections obtained from the single-arm anddouble-arm methods differ only by about 4 mb and agree well within the uncertainties.
Table 3: Summary of cross sections obtained from the two different event selections. The accep-tance definition for σvis is based on the production of stable particles within 3 < |η| < 5 withmomentum pHF > 21.3 GeV/c (11.3 GeV/c) for the single-arm (double-arm) event selections.
The final σinel value is obtained by taking the weighted average of the measured values in thetwo event selections. The statistical uncertainties and the uncertainty on the luminosity arecorrelated between the selections. The degree of correlation among the remaining systematicuncertainties is much smaller and they are taken as uncorrelated. This yields a final result forthe inelastic hadronic cross section of
This result is shown in Fig. 3 compared to other measurements at different centre-of-mass en-ergies and to various theoretical predictions. A pPb cross section was also measured by theALICE Collaboration, amounting to 2090–2120 mb with an uncertainty of 70 mb, with γp con-tributions included and no correction for acceptance applied [41]. A direct comparison to theσobs measured in the analysis presented here is not possible since the two detector acceptancesare different.
The inelastic cross section measured by the CMS experiment is compared to the Glauber-modelprediction (solid curve in Fig. 3) obtained using a pp inelastic cross section at
√s = 5.02 TeV of
70.0± 1.5 mb, derived from the COMPETE parametrisation [42] including the measurement ofthe TOTEM Collaboration at
√s = 7 TeV [43] (where the assigned uncertainty is that measured
8 4 Results and summary
[GeV]NNs10 210 310
[b]
inel
σ
1.6
1.8
2
2.2
2.4
2.6)-1CMS (12.6 nb
IHEPFNALAvakian et al.QGSJETII-04DPMJET3.06(COMPETE+TOTEM)+GlauberDIPSYEPOS-LHC
CMSpPb collisions
Figure 3: Inelastic hadronic cross sections for pPb collisions as a function of the centre-of-massenergy. The measurement described here (circle, with error bars obtained from the quadraticsum of all uncertainties) is compared to lower energy data (squares and triangles) [2, 39, 40]and to different model predictions (curves).
by the latter). The Glauber calculation yields 2130± 40 mb and is compatible with the mea-surement presented here indicating that effects neglected by the calculation (such as nucleoncorrelations and screening) are either small or approximately cancel out. The experimental re-sult is also consistent with the prediction of the DIPSY model [44, 45] based on a dipole-modelapproach including parton saturation and multiple-scattering. Among the Gribov–Regge mod-els, the EPOS prediction is compatible with the measurement within uncertainties, whereas DP-MJET and QGSJETII predict a value more than 1 standard deviation above the data, with a largerdiscrepancy appearing for the σvis cross sections (Table 3). The EPOS and QGSJETII models arecommonly used for cosmic ray air shower simulations. Thus, at the corresponding cosmicray proton energies of Ecr = s/(2mp) = 1016.1 eV, where mp is the mass of the proton, thereare no indications for data-model deviations above ≈5% in the proton-lead collisions studiedhere (note that this corresponds to an “extreme” nuclear mass number scenario, compared tothe lighter nuclei involved in proton-air interactions). In summary, the measurement of thecross sections in pPb collisions presented here is the first such fully corrected measurement atmulti-TeV energies and, thus, provides important constraints on hadronic interaction modelscommonly used in high-energy heavy ion and cosmic ray physics.
AcknowledgmentsWe congratulate our colleagues in the CERN accelerator departments for the excellent perfor-mance of the LHC and thank the technical and administrative staffs at CERN and at other CMSinstitutes for their contributions to the success of the CMS effort. In addition, we gratefullyacknowledge the computing centres and personnel of the Worldwide LHC Computing Gridfor delivering so effectively the computing infrastructure essential to our analyses. Finally, we
References 9
acknowledge the enduring support for the construction and operation of the LHC and the CMSdetector provided by the following funding agencies: BMWFW and FWF (Austria); FNRS andFWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS,MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus);MoER, ERC IUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA andCNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NIH(Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Re-public of Korea); LAS (Lithuania); MOE and UM (Malaysia); CINVESTAV, CONACYT, SEP,and UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland);FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS and RFBR (Russia); MESTD (Serbia);SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter,IPST, STAR and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine);STFC (United Kingdom); DOE and NSF (USA).
Individuals have received support from the Marie-Curie programme and the European Re-search Council and EPLANET (European Union); the Leventis Foundation; the A. P. SloanFoundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Of-fice; the Fonds pour la Formation a la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); theMinistry of Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Scienceand Industrial Research, India; the HOMING PLUS programme of the Foundation for PolishScience, cofinanced from European Union, Regional Development Fund; the OPUS programmeof the National Science Center (Poland); the Compagnia di San Paolo (Torino); the Consorzioper la Fisica (Trieste); MIUR project 20108T4XTM (Italy); the Thalis and Aristeia programmescofinanced by EU-ESF and the Greek NSRF; the National Priorities Research Program by QatarNational Research Fund; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chula-longkorn University (Thailand); and the Welch Foundation, contract C-1845.
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A The CMS CollaborationYerevan Physics Institute, Yerevan, ArmeniaV. Khachatryan, A.M. Sirunyan, A. Tumasyan
Institut fur Hochenergiephysik der OeAW, Wien, AustriaW. Adam, E. Asilar, T. Bergauer, J. Brandstetter, E. Brondolin, M. Dragicevic, J. Ero, M. Flechl,M. Friedl, R. Fruhwirth1, V.M. Ghete, C. Hartl, N. Hormann, J. Hrubec, M. Jeitler1, V. Knunz,A. Konig, M. Krammer1, I. Kratschmer, D. Liko, T. Matsushita, I. Mikulec, D. Rabady2,B. Rahbaran, H. Rohringer, J. Schieck1, R. Schofbeck, J. Strauss, W. Treberer-Treberspurg,W. Waltenberger, C.-E. Wulz1
National Centre for Particle and High Energy Physics, Minsk, BelarusV. Mossolov, N. Shumeiko, J. Suarez Gonzalez
Universiteit Antwerpen, Antwerpen, BelgiumS. Alderweireldt, T. Cornelis, E.A. De Wolf, X. Janssen, A. Knutsson, J. Lauwers, S. Luyckx,S. Ochesanu, R. Rougny, M. Van De Klundert, H. Van Haevermaet, P. Van Mechelen, N. VanRemortel, A. Van Spilbeeck
Vrije Universiteit Brussel, Brussel, BelgiumS. Abu Zeid, F. Blekman, J. D’Hondt, N. Daci, I. De Bruyn, K. Deroover, N. Heracleous,J. Keaveney, S. Lowette, L. Moreels, A. Olbrechts, Q. Python, D. Strom, S. Tavernier, W. VanDoninck, P. Van Mulders, G.P. Van Onsem, I. Van Parijs
Universite Libre de Bruxelles, Bruxelles, BelgiumP. Barria, C. Caillol, B. Clerbaux, G. De Lentdecker, H. Delannoy, G. Fasanella, L. Favart,A.P.R. Gay, A. Grebenyuk, T. Lenzi, A. Leonard, T. Maerschalk, A. Marinov, L. Pernie,A. Randle-conde, T. Reis, T. Seva, C. Vander Velde, P. Vanlaer, R. Yonamine, F. Zenoni, F. Zhang3
Ghent University, Ghent, BelgiumK. Beernaert, L. Benucci, A. Cimmino, S. Crucy, D. Dobur, A. Fagot, G. Garcia, M. Gul,J. Mccartin, A.A. Ocampo Rios, D. Poyraz, D. Ryckbosch, S. Salva, M. Sigamani, N. Strobbe,M. Tytgat, W. Van Driessche, E. Yazgan, N. Zaganidis
Universite Catholique de Louvain, Louvain-la-Neuve, BelgiumS. Basegmez, C. Beluffi4, O. Bondu, S. Brochet, G. Bruno, R. Castello, A. Caudron, L. Ceard,G.G. Da Silveira, C. Delaere, D. Favart, L. Forthomme, A. Giammanco5, J. Hollar, A. Jafari,P. Jez, M. Komm, V. Lemaitre, A. Mertens, C. Nuttens, L. Perrini, A. Pin, K. Piotrzkowski,A. Popov6, L. Quertenmont, M. Selvaggi, M. Vidal Marono
Universite de Mons, Mons, BelgiumN. Beliy, G.H. Hammad
Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, BrazilW.L. Alda Junior, G.A. Alves, L. Brito, M. Correa Martins Junior, C. Hensel, C. Mora Herrera,A. Moraes, M.E. Pol, P. Rebello Teles
Universidade do Estado do Rio de Janeiro, Rio de Janeiro, BrazilE. Belchior Batista Das Chagas, W. Carvalho, J. Chinellato7, A. Custodio, E.M. Da Costa,D. De Jesus Damiao, C. De Oliveira Martins, S. Fonseca De Souza, L.M. Huertas Guativa,H. Malbouisson, D. Matos Figueiredo, L. Mundim, H. Nogima, W.L. Prado Da Silva,A. Santoro, A. Sznajder, E.J. Tonelli Manganote7, A. Vilela Pereira
14 A The CMS Collaboration
Universidade Estadual Paulista a, Universidade Federal do ABC b, Sao Paulo, BrazilS. Ahujaa, C.A. Bernardesb, A. De Souza Santosb, S. Dograa, T.R. Fernandez Perez Tomeia,E.M. Gregoresb, P.G. Mercadanteb, C.S. Moona,8, S.F. Novaesa, Sandra S. Padulaa, D. RomeroAbad, J.C. Ruiz Vargas
Institute for Nuclear Research and Nuclear Energy, Sofia, BulgariaA. Aleksandrov, V. Genchev†, R. Hadjiiska, P. Iaydjiev, S. Piperov, M. Rodozov, S. Stoykova,G. Sultanov, M. Vutova
University of Sofia, Sofia, BulgariaA. Dimitrov, I. Glushkov, L. Litov, B. Pavlov, P. Petkov
Institute of High Energy Physics, Beijing, ChinaM. Ahmad, J.G. Bian, G.M. Chen, H.S. Chen, M. Chen, T. Cheng, R. Du, C.H. Jiang, R. Plestina9,F. Romeo, S.M. Shaheen, J. Tao, C. Wang, Z. Wang, H. Zhang
State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, ChinaC. Asawatangtrakuldee, Y. Ban, Q. Li, S. Liu, Y. Mao, S.J. Qian, D. Wang, Z. Xu, W. Zou
Universidad de Los Andes, Bogota, ColombiaC. Avila, A. Cabrera, L.F. Chaparro Sierra, C. Florez, J.P. Gomez, B. Gomez Moreno,J.C. Sanabria
University of Split, Faculty of Electrical Engineering, Mechanical Engineering and NavalArchitecture, Split, CroatiaN. Godinovic, D. Lelas, D. Polic, I. Puljak, P.M. Ribeiro Cipriano
University of Split, Faculty of Science, Split, CroatiaZ. Antunovic, M. Kovac
Institute Rudjer Boskovic, Zagreb, CroatiaV. Brigljevic, K. Kadija, J. Luetic, S. Micanovic, L. Sudic
University of Cyprus, Nicosia, CyprusA. Attikis, G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis, H. Rykaczewski
Charles University, Prague, Czech RepublicM. Bodlak, M. Finger10, M. Finger Jr.10
Academy of Scientific Research and Technology of the Arab Republic of Egypt, EgyptianNetwork of High Energy Physics, Cairo, EgyptA.A. Abdelalim11, A. Mahrous12, A. Radi13,14
National Institute of Chemical Physics and Biophysics, Tallinn, EstoniaB. Calpas, M. Kadastik, M. Murumaa, M. Raidal, A. Tiko, C. Veelken
Department of Physics, University of Helsinki, Helsinki, FinlandP. Eerola, J. Pekkanen, M. Voutilainen
Helsinki Institute of Physics, Helsinki, FinlandJ. Harkonen, V. Karimaki, R. Kinnunen, T. Lampen, K. Lassila-Perini, S. Lehti, T. Linden,P. Luukka, T. Maenpaa, T. Peltola, E. Tuominen, J. Tuominiemi, E. Tuovinen, L. Wendland
Lappeenranta University of Technology, Lappeenranta, FinlandJ. Talvitie, T. Tuuva
15
DSM/IRFU, CEA/Saclay, Gif-sur-Yvette, FranceM. Besancon, F. Couderc, M. Dejardin, D. Denegri, B. Fabbro, J.L. Faure, C. Favaro, F. Ferri,S. Ganjour, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, E. Locci, M. Machet,J. Malcles, J. Rander, A. Rosowsky, M. Titov, A. Zghiche
Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, FranceI. Antropov, S. Baffioni, F. Beaudette, P. Busson, L. Cadamuro, E. Chapon, C. Charlot, T. Dahms,O. Davignon, N. Filipovic, A. Florent, R. Granier de Cassagnac, S. Lisniak, L. Mastrolorenzo,P. Mine, I.N. Naranjo, M. Nguyen, C. Ochando, G. Ortona, P. Paganini, S. Regnard, R. Salerno,J.B. Sauvan, Y. Sirois, T. Strebler, Y. Yilmaz, A. Zabi
Institut Pluridisciplinaire Hubert Curien, Universite de Strasbourg, Universite de HauteAlsace Mulhouse, CNRS/IN2P3, Strasbourg, FranceJ.-L. Agram15, J. Andrea, A. Aubin, D. Bloch, J.-M. Brom, M. Buttignol, E.C. Chabert,N. Chanon, C. Collard, E. Conte15, X. Coubez, J.-C. Fontaine15, D. Gele, U. Goerlach,C. Goetzmann, A.-C. Le Bihan, J.A. Merlin2, K. Skovpen, P. Van Hove
Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique des Particules,CNRS/IN2P3, Villeurbanne, FranceS. Gadrat
Universite de Lyon, Universite Claude Bernard Lyon 1, CNRS-IN2P3, Institut de PhysiqueNucleaire de Lyon, Villeurbanne, FranceS. Beauceron, C. Bernet, G. Boudoul, E. Bouvier, C.A. Carrillo Montoya, J. Chasserat, R. Chierici,D. Contardo, B. Courbon, P. Depasse, H. El Mamouni, J. Fan, J. Fay, S. Gascon, M. Gouzevitch,B. Ille, F. Lagarde, I.B. Laktineh, M. Lethuillier, L. Mirabito, A.L. Pequegnot, S. Perries, J.D. RuizAlvarez, D. Sabes, L. Sgandurra, V. Sordini, M. Vander Donckt, P. Verdier, S. Viret, H. Xiao
Georgian Technical University, Tbilisi, GeorgiaT. Toriashvili16
Tbilisi State University, Tbilisi, GeorgiaI. Bagaturia17
RWTH Aachen University, I. Physikalisches Institut, Aachen, GermanyC. Autermann, S. Beranek, M. Edelhoff, L. Feld, A. Heister, M.K. Kiesel, K. Klein, M. Lipinski,A. Ostapchuk, M. Preuten, F. Raupach, S. Schael, J.F. Schulte, T. Verlage, H. Weber, B. Wittmer,V. Zhukov6
RWTH Aachen University, III. Physikalisches Institut A, Aachen, GermanyM. Ata, M. Brodski, E. Dietz-Laursonn, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg,T. Esch, R. Fischer, A. Guth, T. Hebbeker, C. Heidemann, K. Hoepfner, D. Klingebiel,S. Knutzen, P. Kreuzer, M. Merschmeyer, A. Meyer, P. Millet, M. Olschewski, K. Padeken,P. Papacz, T. Pook, M. Radziej, H. Reithler, M. Rieger, F. Scheuch, L. Sonnenschein, D. Teyssier,S. Thuer
RWTH Aachen University, III. Physikalisches Institut B, Aachen, GermanyV. Cherepanov, Y. Erdogan, G. Flugge, H. Geenen, M. Geisler, F. Hoehle, B. Kargoll, T. Kress,Y. Kuessel, A. Kunsken, J. Lingemann2, A. Nehrkorn, A. Nowack, I.M. Nugent, C. Pistone,O. Pooth, A. Stahl
Deutsches Elektronen-Synchrotron, Hamburg, GermanyM. Aldaya Martin, I. Asin, N. Bartosik, O. Behnke, U. Behrens, A.J. Bell, K. Borras,A. Burgmeier, A. Cakir, L. Calligaris, A. Campbell, S. Choudhury, F. Costanza, C. Diez
16 A The CMS Collaboration
Pardos, G. Dolinska, S. Dooling, T. Dorland, G. Eckerlin, D. Eckstein, T. Eichhorn, G. Flucke,E. Gallo, J. Garay Garcia, A. Geiser, A. Gizhko, P. Gunnellini, J. Hauk, M. Hempel18, H. Jung,A. Kalogeropoulos, O. Karacheban18, M. Kasemann, P. Katsas, J. Kieseler, C. Kleinwort, I. Korol,W. Lange, J. Leonard, K. Lipka, A. Lobanov, W. Lohmann18, R. Mankel, I. Marfin18, I.-A. Melzer-Pellmann, A.B. Meyer, G. Mittag, J. Mnich, A. Mussgiller, S. Naumann-Emme, A. Nayak,E. Ntomari, H. Perrey, D. Pitzl, R. Placakyte, A. Raspereza, B. Roland, M.O. Sahin, P. Saxena,T. Schoerner-Sadenius, M. Schroder, C. Seitz, S. Spannagel, K.D. Trippkewitz, R. Walsh,C. Wissing
University of Hamburg, Hamburg, GermanyV. Blobel, M. Centis Vignali, A.R. Draeger, J. Erfle, E. Garutti, K. Goebel, D. Gonzalez,M. Gorner, J. Haller, M. Hoffmann, R.S. Hoing, A. Junkes, R. Klanner, R. Kogler, T. Lapsien,T. Lenz, I. Marchesini, D. Marconi, D. Nowatschin, J. Ott, F. Pantaleo2, T. Peiffer, A. Perieanu,N. Pietsch, J. Poehlsen, D. Rathjens, C. Sander, H. Schettler, P. Schleper, E. Schlieckau,A. Schmidt, J. Schwandt, M. Seidel, V. Sola, H. Stadie, G. Steinbruck, H. Tholen, D. Troendle,E. Usai, L. Vanelderen, A. Vanhoefer
Institut fur Experimentelle Kernphysik, Karlsruhe, GermanyM. Akbiyik, C. Barth, C. Baus, J. Berger, C. Boser, E. Butz, T. Chwalek, F. Colombo, W. DeBoer, A. Descroix, A. Dierlamm, S. Fink, F. Frensch, M. Giffels, A. Gilbert, F. Hartmann2,S.M. Heindl, U. Husemann, F. Kassel2, I. Katkov6, A. Kornmayer2, P. Lobelle Pardo, B. Maier,H. Mildner, M.U. Mozer, T. Muller, Th. Muller, M. Plagge, G. Quast, K. Rabbertz, S. Rocker,F. Roscher, H.J. Simonis, F.M. Stober, R. Ulrich, J. Wagner-Kuhr, S. Wayand, M. Weber, T. Weiler,C. Wohrmann, R. Wolf
Institute of Nuclear and Particle Physics (INPP), NCSR Demokritos, Aghia Paraskevi,GreeceG. Anagnostou, G. Daskalakis, T. Geralis, V.A. Giakoumopoulou, A. Kyriakis, D. Loukas,A. Psallidas, I. Topsis-Giotis
University of Athens, Athens, GreeceA. Agapitos, S. Kesisoglou, A. Panagiotou, N. Saoulidou, E. Tziaferi
University of Ioannina, Ioannina, GreeceI. Evangelou, G. Flouris, C. Foudas, P. Kokkas, N. Loukas, N. Manthos, I. Papadopoulos,E. Paradas, J. Strologas
Wigner Research Centre for Physics, Budapest, HungaryG. Bencze, C. Hajdu, A. Hazi, P. Hidas, D. Horvath19, F. Sikler, V. Veszpremi, G. Vesztergombi20,A.J. Zsigmond
Institute of Nuclear Research ATOMKI, Debrecen, HungaryN. Beni, S. Czellar, J. Karancsi21, J. Molnar, Z. Szillasi
University of Debrecen, Debrecen, HungaryM. Bartok22, A. Makovec, P. Raics, Z.L. Trocsanyi, B. Ujvari
National Institute of Science Education and Research, Bhubaneswar, IndiaP. Mal, K. Mandal, N. Sahoo, S.K. Swain
Panjab University, Chandigarh, IndiaS. Bansal, S.B. Beri, V. Bhatnagar, R. Chawla, R. Gupta, U.Bhawandeep, A.K. Kalsi, A. Kaur,M. Kaur, R. Kumar, A. Mehta, M. Mittal, N. Nishu, J.B. Singh, G. Walia
17
University of Delhi, Delhi, IndiaAshok Kumar, Arun Kumar, A. Bhardwaj, B.C. Choudhary, R.B. Garg, A. Kumar, S. Malhotra,M. Naimuddin, K. Ranjan, R. Sharma, V. Sharma
Saha Institute of Nuclear Physics, Kolkata, IndiaS. Banerjee, S. Bhattacharya, K. Chatterjee, S. Dey, S. Dutta, Sa. Jain, N. Majumdar, A. Modak,K. Mondal, S. Mukherjee, S. Mukhopadhyay, A. Roy, D. Roy, S. Roy Chowdhury, S. Sarkar,M. Sharan
Bhabha Atomic Research Centre, Mumbai, IndiaA. Abdulsalam, R. Chudasama, D. Dutta, V. Jha, V. Kumar, A.K. Mohanty2, L.M. Pant,P. Shukla, A. Topkar
Tata Institute of Fundamental Research, Mumbai, IndiaT. Aziz, S. Banerjee, S. Bhowmik23, R.M. Chatterjee, R.K. Dewanjee, S. Dugad, S. Ganguly,S. Ghosh, M. Guchait, A. Gurtu24, G. Kole, S. Kumar, B. Mahakud, M. Maity23, G. Majumder,K. Mazumdar, S. Mitra, G.B. Mohanty, B. Parida, T. Sarkar23, K. Sudhakar, N. Sur, B. Sutar,N. Wickramage25
Indian Institute of Science Education and Research (IISER), Pune, IndiaS. Chauhan, S. Dube, S. Sharma
Institute for Research in Fundamental Sciences (IPM), Tehran, IranH. Bakhshiansohi, H. Behnamian, S.M. Etesami26, A. Fahim27, R. Goldouzian, M. Khakzad,M. Mohammadi Najafabadi, M. Naseri, S. Paktinat Mehdiabadi, F. Rezaei Hosseinabadi,B. Safarzadeh28, M. Zeinali
University College Dublin, Dublin, IrelandM. Felcini, M. Grunewald
INFN Sezione di Bari a, Universita di Bari b, Politecnico di Bari c, Bari, ItalyM. Abbresciaa ,b, C. Calabriaa,b, C. Caputoa,b, S.S. Chhibraa,b, A. Colaleoa, D. Creanzaa,c,L. Cristellaa,b, N. De Filippisa ,c, M. De Palmaa ,b, L. Fiorea, G. Iasellia ,c, G. Maggia,c, M. Maggia,G. Minielloa ,b, S. Mya ,c, S. Nuzzoa ,b, A. Pompilia ,b, G. Pugliesea ,c, R. Radognaa ,b, A. Ranieria,G. Selvaggia,b, L. Silvestrisa ,2, R. Vendittia,b, P. Verwilligena
INFN Sezione di Bologna a, Universita di Bologna b, Bologna, ItalyG. Abbiendia, C. Battilana2, A.C. Benvenutia, D. Bonacorsia,b, S. Braibant-Giacomellia ,b,L. Brigliadoria ,b, R. Campaninia,b, P. Capiluppia,b, A. Castroa ,b, F.R. Cavalloa, G. Codispotia ,b,M. Cuffiania ,b, G.M. Dallavallea, F. Fabbria, A. Fanfania,b, D. Fasanellaa ,b, P. Giacomellia,C. Grandia, L. Guiduccia ,b, S. Marcellinia, G. Masettia, A. Montanaria, F.L. Navarriaa ,b,A. Perrottaa, A.M. Rossia ,b, T. Rovellia ,b, G.P. Sirolia ,b, N. Tosia ,b, R. Travaglinia ,b
INFN Sezione di Catania a, Universita di Catania b, CSFNSM c, Catania, ItalyG. Cappelloa, M. Chiorbolia,b, S. Costaa,b, F. Giordanoa, R. Potenzaa,b, A. Tricomia,b, C. Tuvea ,b
INFN Sezione di Firenze a, Universita di Firenze b, Firenze, ItalyG. Barbaglia, V. Ciullia ,b, C. Civininia, R. D’Alessandroa ,b, E. Focardia ,b, S. Gonzia ,b, V. Goria ,b,P. Lenzia ,b, M. Meschinia, S. Paolettia, G. Sguazzonia, A. Tropianoa,b, L. Viliania,b
INFN Laboratori Nazionali di Frascati, Frascati, ItalyL. Benussi, S. Bianco, F. Fabbri, D. Piccolo
INFN Sezione di Genova a, Universita di Genova b, Genova, ItalyV. Calvellia ,b, F. Ferroa, M. Lo Veterea,b, M.R. Mongea ,b, E. Robuttia, S. Tosia ,b
18 A The CMS Collaboration
INFN Sezione di Milano-Bicocca a, Universita di Milano-Bicocca b, Milano, ItalyL. Brianza, M.E. Dinardoa ,b, S. Fiorendia ,b, S. Gennaia, R. Gerosaa,b, A. Ghezzia,b, P. Govonia ,b,S. Malvezzia, R.A. Manzonia,b, B. Marzocchia ,b ,2, D. Menascea, L. Moronia, M. Paganonia ,b,D. Pedrinia, S. Ragazzia ,b, N. Redaellia, T. Tabarelli de Fatisa ,b
INFN Sezione di Napoli a, Universita di Napoli ’Federico II’ b, Napoli, Italy, Universita dellaBasilicata c, Potenza, Italy, Universita G. Marconi d, Roma, ItalyS. Buontempoa, N. Cavalloa,c, S. Di Guidaa,d ,2, M. Espositoa,b, F. Fabozzia,c, A.O.M. Iorioa ,b,G. Lanzaa, L. Listaa, S. Meolaa,d ,2, M. Merolaa, P. Paoluccia ,2, C. Sciaccaa,b, F. Thyssen
INFN Sezione di Padova a, Universita di Padova b, Padova, Italy, Universita di Trento c,Trento, ItalyP. Azzia,2, N. Bacchettaa, M. Bellatoa, L. Benatoa ,b, A. Bolettia ,b, A. Brancaa,b, M. Dall’Ossoa,b ,2,T. Dorigoa, F. Fanzagoa, F. Gonellaa, A. Gozzelinoa, K. Kanishcheva ,c, S. Lacapraraa,M. Margonia,b, G. Marona ,29, A.T. Meneguzzoa,b, M. Michelottoa, F. Montecassianoa,M. Passaseoa, J. Pazzinia ,b, M. Pegoraroa, N. Pozzobona ,b, P. Ronchesea,b, F. Simonettoa ,b,E. Torassaa, M. Tosia ,b, M. Zanetti, P. Zottoa ,b, A. Zucchettaa ,b ,2
INFN Sezione di Pavia a, Universita di Pavia b, Pavia, ItalyA. Braghieria, A. Magnania, P. Montagnaa ,b, S.P. Rattia,b, V. Rea, C. Riccardia ,b, P. Salvinia, I. Vaia,P. Vituloa ,b
INFN Sezione di Perugia a, Universita di Perugia b, Perugia, ItalyL. Alunni Solestizia,b, M. Biasinia,b, G.M. Bileia, D. Ciangottinia ,b ,2, L. Fanoa ,b, P. Laricciaa ,b,G. Mantovania,b, M. Menichellia, A. Sahaa, A. Santocchiaa,b, A. Spieziaa,b
INFN Sezione di Pisa a, Universita di Pisa b, Scuola Normale Superiore di Pisa c, Pisa, ItalyK. Androsova,30, P. Azzurria, G. Bagliesia, J. Bernardinia, T. Boccalia, G. Broccoloa,c, R. Castaldia,M.A. Cioccia ,30, R. Dell’Orsoa, S. Donatoa,c ,2, G. Fedi, L. Foaa,c†, A. Giassia, M.T. Grippoa,30,F. Ligabuea,c, T. Lomtadzea, L. Martinia ,b, A. Messineoa ,b, F. Pallaa, A. Rizzia ,b, A. Savoy-Navarroa ,31, A.T. Serbana, P. Spagnoloa, P. Squillaciotia,30, R. Tenchinia, G. Tonellia ,b,A. Venturia, P.G. Verdinia
INFN Sezione di Roma a, Universita di Roma b, Roma, ItalyL. Baronea ,b, F. Cavallaria, G. D’imperioa ,b ,2, D. Del Rea,b, M. Diemoza, S. Gellia ,b, C. Jordaa,E. Longoa,b, F. Margarolia,b, P. Meridiania, F. Michelia ,b, G. Organtinia ,b, R. Paramattia,F. Preiatoa,b, S. Rahatloua ,b, C. Rovellia, F. Santanastasioa ,b, P. Traczyka,b ,2
INFN Sezione di Torino a, Universita di Torino b, Torino, Italy, Universita del PiemonteOrientale c, Novara, ItalyN. Amapanea,b, R. Arcidiaconoa ,c,2, S. Argiroa ,b, M. Arneodoa,c, R. Bellana ,b, C. Biinoa,N. Cartigliaa, M. Costaa ,b, R. Covarellia,b, A. Deganoa,b, N. Demariaa, L. Fincoa,b ,2, C. Mariottia,S. Masellia, E. Migliorea ,b, V. Monacoa ,b, E. Monteila ,b, M. Musicha, M.M. Obertinoa ,b,L. Pachera,b, N. Pastronea, M. Pelliccionia, G.L. Pinna Angionia ,b, F. Raveraa,b, A. Romeroa ,b,M. Ruspaa,c, R. Sacchia,b, A. Solanoa,b, A. Staianoa, U. Tamponia, P.P. Trapania ,b
INFN Sezione di Trieste a, Universita di Trieste b, Trieste, ItalyS. Belfortea, V. Candelisea ,b ,2, M. Casarsaa, F. Cossuttia, G. Della Riccaa,b, B. Gobboa, C. LaLicataa,b, M. Maronea ,b, A. Schizzia,b, T. Umera,b, A. Zanettia
Kangwon National University, Chunchon, KoreaS. Chang, A. Kropivnitskaya, S.K. Nam
19
Kyungpook National University, Daegu, KoreaD.H. Kim, G.N. Kim, M.S. Kim, D.J. Kong, S. Lee, Y.D. Oh, A. Sakharov, D.C. Son
Chonbuk National University, Jeonju, KoreaJ.A. Brochero Cifuentes, H. Kim, T.J. Kim, M.S. Ryu
Chonnam National University, Institute for Universe and Elementary Particles, Kwangju,KoreaS. Song
Korea University, Seoul, KoreaS. Choi, Y. Go, D. Gyun, B. Hong, M. Jo, H. Kim, Y. Kim, B. Lee, K. Lee, K.S. Lee, S. Lee,S.K. Park, Y. Roh
Seoul National University, Seoul, KoreaH.D. Yoo
University of Seoul, Seoul, KoreaM. Choi, H. Kim, J.H. Kim, J.S.H. Lee, I.C. Park, G. Ryu
Sungkyunkwan University, Suwon, KoreaY. Choi, Y.K. Choi, J. Goh, D. Kim, E. Kwon, J. Lee, I. Yu
Vilnius University, Vilnius, LithuaniaA. Juodagalvis, J. Vaitkus
National Centre for Particle Physics, Universiti Malaya, Kuala Lumpur, MalaysiaI. Ahmed, Z.A. Ibrahim, J.R. Komaragiri, M.A.B. Md Ali32, F. Mohamad Idris33, W.A.T. WanAbdullah, M.N. Yusli
Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, MexicoE. Casimiro Linares, H. Castilla-Valdez, E. De La Cruz-Burelo, I. Heredia-de La Cruz34,A. Hernandez-Almada, R. Lopez-Fernandez, A. Sanchez-Hernandez
Universidad Iberoamericana, Mexico City, MexicoS. Carrillo Moreno, F. Vazquez Valencia
Benemerita Universidad Autonoma de Puebla, Puebla, MexicoS. Carpinteyro, I. Pedraza, H.A. Salazar Ibarguen
Universidad Autonoma de San Luis Potosı, San Luis Potosı, MexicoA. Morelos Pineda
University of Auckland, Auckland, New ZealandD. Krofcheck
University of Canterbury, Christchurch, New ZealandP.H. Butler, S. Reucroft
National Centre for Physics, Quaid-I-Azam University, Islamabad, PakistanA. Ahmad, M. Ahmad, Q. Hassan, H.R. Hoorani, W.A. Khan, T. Khurshid, M. Shoaib
National Centre for Nuclear Research, Swierk, PolandH. Bialkowska, M. Bluj, B. Boimska, T. Frueboes, M. Gorski, M. Kazana, K. Nawrocki,K. Romanowska-Rybinska, M. Szleper, P. Zalewski
20 A The CMS Collaboration
Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, PolandG. Brona, K. Bunkowski, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski, M. Misiura,M. Olszewski, M. Walczak
Laboratorio de Instrumentacao e Fısica Experimental de Partıculas, Lisboa, PortugalP. Bargassa, C. Beirao Da Cruz E Silva, A. Di Francesco, P. Faccioli, P.G. Ferreira Parracho,M. Gallinaro, N. Leonardo, L. Lloret Iglesias, F. Nguyen, J. Rodrigues Antunes, J. Seixas,O. Toldaiev, D. Vadruccio, J. Varela, P. Vischia
Joint Institute for Nuclear Research, Dubna, RussiaS. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, I. Gorbunov, A. Kamenev, V. Karjavin,V. Konoplyanikov, A. Lanev, A. Malakhov, V. Matveev35, P. Moisenz, V. Palichik, V. Perelygin,S. Shmatov, S. Shulha, N. Skatchkov, V. Smirnov, A. Zarubin
Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), RussiaV. Golovtsov, Y. Ivanov, V. Kim36, E. Kuznetsova, P. Levchenko, V. Murzin, V. Oreshkin,I. Smirnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev
Institute for Nuclear Research, Moscow, RussiaYu. 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, Moscow, RussiaV. Epshteyn, V. Gavrilov, N. Lychkovskaya, V. Popov, I. Pozdnyakov, G. Safronov,A. Spiridonov, E. Vlasov, A. Zhokin
National Research Nuclear University ’Moscow Engineering Physics Institute’ (MEPhI),Moscow, RussiaA. Bylinkin
P.N. Lebedev Physical Institute, Moscow, RussiaV. Andreev, M. Azarkin37, I. Dremin37, M. Kirakosyan, A. Leonidov37, G. Mesyats, S.V. Rusakov,A. Vinogradov
Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow,RussiaA. Baskakov, A. Belyaev, E. Boos, A. Ershov, A. Gribushin, L. Khein, V. Klyukhin, O. Kodolova,I. Lokhtin, O. Lukina, I. Myagkov, S. Obraztsov, S. Petrushanko, V. Savrin, A. Snigirev
State Research Center of Russian Federation, Institute for High Energy Physics, Protvino,RussiaI. Azhgirey, I. Bayshev, S. Bitioukov, V. Kachanov, A. Kalinin, D. Konstantinov, V. Krychkine,V. Petrov, R. Ryutin, A. Sobol, L. Tourtchanovitch, S. Troshin, N. Tyurin, A. Uzunian, A. Volkov
University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade,SerbiaP. Adzic38, M. Ekmedzic, J. Milosevic, V. Rekovic
Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT),Madrid, SpainJ. Alcaraz Maestre, E. Calvo, M. Cerrada, M. Chamizo Llatas, N. Colino, B. De La Cruz,A. Delgado Peris, D. Domınguez Vazquez, A. Escalante Del Valle, C. Fernandez Bedoya,J.P. Fernandez Ramos, J. Flix, M.C. Fouz, P. Garcia-Abia, O. Gonzalez Lopez, S. Goy Lopez,J.M. Hernandez, M.I. Josa, E. Navarro De Martino, A. Perez-Calero Yzquierdo, J. Puerta Pelayo,A. Quintario Olmeda, I. Redondo, L. Romero, M.S. Soares
21
Universidad Autonoma de Madrid, Madrid, SpainC. Albajar, J.F. de Troconiz, M. Missiroli, D. Moran
Universidad de Oviedo, Oviedo, SpainH. Brun, J. Cuevas, J. Fernandez Menendez, S. Folgueras, I. Gonzalez Caballero, E. PalenciaCortezon, J.M. Vizan Garcia
Instituto de Fısica de Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, SpainI.J. Cabrillo, A. Calderon, J.R. Castineiras De Saa, P. De Castro Manzano, J. Duarte Campderros,M. Fernandez, G. Gomez, A. Graziano, A. Lopez Virto, J. Marco, R. Marco, C. Martinez Rivero,F. Matorras, F.J. Munoz Sanchez, J. Piedra Gomez, T. Rodrigo, A.Y. Rodrıguez-Marrero, A. Ruiz-Jimeno, L. Scodellaro, I. Vila, R. Vilar Cortabitarte
CERN, European Organization for Nuclear Research, Geneva, SwitzerlandD. Abbaneo, E. Auffray, G. Auzinger, M. Bachtis, P. Baillon, A.H. Ball, D. Barney, A. Benaglia,J. Bendavid, L. Benhabib, J.F. Benitez, G.M. Berruti, P. Bloch, A. Bocci, A. Bonato, C. Botta,H. Breuker, T. Camporesi, G. Cerminara, S. Colafranceschi39, M. D’Alfonso, D. d’Enterria,A. Dabrowski, V. Daponte, A. David, M. De Gruttola, F. De Guio, A. De Roeck, S. De Visscher,E. Di Marco, M. Dobson, M. Dordevic, T. du Pree, N. Dupont, A. Elliott-Peisert, G. Franzoni,W. Funk, D. Gigi, K. Gill, D. Giordano, M. Girone, F. Glege, R. Guida, S. Gundacker, M. Guthoff,J. Hammer, M. Hansen, P. Harris, J. Hegeman, V. Innocente, P. Janot, H. Kirschenmann,M.J. Kortelainen, K. Kousouris, K. Krajczar, P. Lecoq, C. Lourenco, M.T. Lucchini, N. Magini,L. Malgeri, M. Mannelli, A. Martelli, L. Masetti, F. Meijers, S. Mersi, E. Meschi, F. Moortgat,S. Morovic, M. Mulders, M.V. Nemallapudi, H. Neugebauer, S. Orfanelli40, L. Orsini, L. Pape,E. Perez, A. Petrilli, G. Petrucciani, A. Pfeiffer, D. Piparo, A. Racz, G. Rolandi41, M. Rovere,M. Ruan, H. Sakulin, C. Schafer, C. Schwick, A. Sharma, P. Silva, M. Simon, P. Sphicas42,D. Spiga, J. Steggemann, B. Stieger, M. Stoye, Y. Takahashi, D. Treille, A. Triossi, A. Tsirou,G.I. Veres20, N. Wardle, H.K. Wohri, A. Zagozdzinska43, W.D. Zeuner
Paul Scherrer Institut, Villigen, SwitzerlandW. Bertl, K. Deiters, W. Erdmann, R. Horisberger, Q. Ingram, H.C. Kaestli, D. Kotlinski,U. Langenegger, D. Renker, T. Rohe
Institute for Particle Physics, ETH Zurich, Zurich, SwitzerlandF. Bachmair, L. Bani, L. Bianchini, M.A. Buchmann, B. Casal, G. Dissertori, M. Dittmar,M. Donega, M. Dunser, P. Eller, C. Grab, C. Heidegger, D. Hits, J. Hoss, G. Kasieczka,W. Lustermann, B. Mangano, A.C. Marini, M. Marionneau, P. Martinez Ruiz del Arbol,M. Masciovecchio, D. Meister, P. Musella, F. Nessi-Tedaldi, F. Pandolfi, J. Pata, F. Pauss,L. Perrozzi, M. Peruzzi, M. Quittnat, M. Rossini, A. Starodumov44, M. Takahashi, V.R. Tavolaro,K. Theofilatos, R. Wallny
Universitat Zurich, Zurich, SwitzerlandT.K. Aarrestad, C. Amsler45, L. Caminada, M.F. Canelli, V. Chiochia, A. De Cosa, C. Galloni,A. Hinzmann, T. Hreus, B. Kilminster, C. Lange, J. Ngadiuba, D. Pinna, P. Robmann, F.J. Ronga,D. Salerno, S. Taroni, Y. Yang
National Central University, Chung-Li, TaiwanM. Cardaci, K.H. Chen, T.H. Doan, C. Ferro, Sh. Jain, R. Khurana, M. Konyushikhin, C.M. Kuo,W. Lin, Y.J. Lu, R. Volpe, S.S. Yu
National Taiwan University (NTU), Taipei, TaiwanR. Bartek, P. Chang, Y.H. Chang, Y.W. Chang, Y. Chao, K.F. Chen, P.H. Chen, C. Dietz, F. Fiori,
22 A The CMS Collaboration
U. Grundler, W.-S. Hou, Y. Hsiung, Y.F. Liu, R.-S. Lu, M. Minano Moya, E. Petrakou, J.F. Tsai,Y.M. Tzeng
Chulalongkorn University, Faculty of Science, Department of Physics, Bangkok, ThailandB. Asavapibhop, K. Kovitanggoon, G. Singh, N. Srimanobhas, N. Suwonjandee
Cukurova University, Adana, TurkeyA. Adiguzel, S. Cerci46, C. Dozen, I. Dumanoglu, S. Girgis, G. Gokbulut, Y. Guler, E. Gurpinar,I. Hos, E.E. Kangal47, A. Kayis Topaksu, G. Onengut48, K. Ozdemir49, S. Ozturk50, B. Tali46,H. Topakli50, M. Vergili, C. Zorbilmez
Middle East Technical University, Physics Department, Ankara, TurkeyI.V. Akin, B. Bilin, S. Bilmis, B. Isildak51, G. Karapinar52, U.E. Surat, M. Yalvac, M. Zeyrek
Bogazici University, Istanbul, TurkeyE.A. Albayrak53, E. Gulmez, M. Kaya54, O. Kaya55, T. Yetkin56
Istanbul Technical University, Istanbul, TurkeyK. Cankocak, S. Sen57, F.I. Vardarlı
Institute for Scintillation Materials of National Academy of Science of Ukraine, Kharkov,UkraineB. Grynyov
National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, UkraineL. Levchuk, P. Sorokin
University of Bristol, Bristol, United KingdomR. Aggleton, F. Ball, L. Beck, J.J. Brooke, E. Clement, D. Cussans, H. Flacher, J. Goldstein,M. Grimes, G.P. Heath, H.F. Heath, J. Jacob, L. Kreczko, C. Lucas, Z. Meng, D.M. Newbold58,S. Paramesvaran, A. Poll, T. Sakuma, S. Seif El Nasr-storey, S. Senkin, D. Smith, V.J. Smith
Rutherford Appleton Laboratory, Didcot, United KingdomK.W. Bell, A. Belyaev59, C. Brew, R.M. Brown, D.J.A. Cockerill, J.A. Coughlan, K. Harder,S. Harper, E. Olaiya, D. Petyt, C.H. Shepherd-Themistocleous, A. Thea, L. Thomas, I.R. Tomalin,T. Williams, W.J. Womersley, S.D. Worm
Imperial College, London, United KingdomM. Baber, R. Bainbridge, O. Buchmuller, A. Bundock, D. Burton, S. Casasso, M. Citron,D. Colling, L. Corpe, N. Cripps, P. Dauncey, G. Davies, A. De Wit, M. Della Negra, P. Dunne,A. Elwood, W. Ferguson, J. Fulcher, D. Futyan, G. Hall, G. Iles, G. Karapostoli, M. Kenzie,R. Lane, R. Lucas58, L. Lyons, A.-M. Magnan, S. Malik, J. Nash, A. Nikitenko44, J. Pela,M. Pesaresi, K. Petridis, D.M. Raymond, A. Richards, A. Rose, C. Seez, A. Tapper, K. Uchida,M. Vazquez Acosta60, T. Virdee, S.C. Zenz
Brunel University, Uxbridge, United KingdomJ.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, D. Leggat, D. Leslie, I.D. Reid, P. Symonds,L. Teodorescu, M. Turner
Baylor University, Waco, USAA. Borzou, K. Call, J. Dittmann, K. Hatakeyama, A. Kasmi, H. Liu, N. Pastika
The University of Alabama, Tuscaloosa, USAO. Charaf, S.I. Cooper, C. Henderson, P. Rumerio
23
Boston University, Boston, USAA. Avetisyan, T. Bose, C. Fantasia, D. Gastler, P. Lawson, D. Rankin, C. Richardson, J. Rohlf,J. St. John, L. Sulak, D. Zou
Brown University, Providence, USAJ. Alimena, E. Berry, S. Bhattacharya, D. Cutts, N. Dhingra, A. Ferapontov, A. Garabedian,U. Heintz, E. Laird, G. Landsberg, Z. Mao, M. Narain, S. Sagir, T. Sinthuprasith
University of California, Davis, Davis, USAR. Breedon, G. Breto, M. Calderon De La Barca Sanchez, S. Chauhan, M. Chertok, J. Conway,R. Conway, P.T. Cox, R. Erbacher, M. Gardner, W. Ko, R. Lander, M. Mulhearn, D. Pellett, J. Pilot,F. Ricci-Tam, S. Shalhout, J. Smith, M. Squires, D. Stolp, M. Tripathi, S. Wilbur, R. Yohay
University of California, Los Angeles, USAR. Cousins, P. Everaerts, C. Farrell, J. Hauser, M. Ignatenko, D. Saltzberg, E. Takasugi, V. Valuev,M. Weber
University of California, Riverside, Riverside, USAK. Burt, R. Clare, J. Ellison, J.W. Gary, G. Hanson, J. Heilman, M. Ivova PANEVA, P. Jandir,E. Kennedy, F. Lacroix, O.R. Long, A. Luthra, M. Malberti, M. Olmedo Negrete, A. Shrinivas,H. Wei, S. Wimpenny
University of California, San Diego, La Jolla, USAJ.G. Branson, G.B. Cerati, S. Cittolin, R.T. D’Agnolo, A. Holzner, R. Kelley, D. Klein, J. Letts,I. Macneill, D. Olivito, S. Padhi, M. Pieri, M. Sani, V. Sharma, S. Simon, M. Tadel, A. Vartak,S. Wasserbaech61, C. Welke, F. Wurthwein, A. Yagil, G. Zevi Della Porta
University of California, Santa Barbara, Santa Barbara, USAD. Barge, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, K. Flowers, M. Franco Sevilla,P. Geffert, C. George, F. Golf, L. Gouskos, J. Gran, J. Incandela, C. Justus, N. Mccoll, S.D. Mullin,J. Richman, D. Stuart, I. Suarez, W. To, C. West, J. Yoo
California Institute of Technology, Pasadena, USAD. Anderson, A. Apresyan, A. Bornheim, J. Bunn, Y. Chen, J. Duarte, A. Mott, H.B. Newman,C. Pena, M. Pierini, M. Spiropulu, J.R. Vlimant, S. Xie, R.Y. Zhu
Carnegie Mellon University, Pittsburgh, USAV. Azzolini, A. Calamba, B. Carlson, T. Ferguson, Y. Iiyama, M. Paulini, J. Russ, M. Sun,H. Vogel, I. Vorobiev
University of Colorado Boulder, Boulder, USAJ.P. Cumalat, W.T. Ford, A. Gaz, F. Jensen, A. Johnson, M. Krohn, T. Mulholland, U. Nauenberg,J.G. Smith, K. Stenson, S.R. Wagner
Cornell University, Ithaca, USAJ. Alexander, A. Chatterjee, J. Chaves, J. Chu, S. Dittmer, N. Eggert, N. Mirman, G. NicolasKaufman, J.R. Patterson, A. Rinkevicius, A. Ryd, L. Skinnari, L. Soffi, W. Sun, S.M. Tan,W.D. Teo, J. Thom, J. Thompson, J. Tucker, Y. Weng, P. Wittich
Fermi National Accelerator Laboratory, Batavia, USAS. Abdullin, M. Albrow, J. Anderson, G. Apollinari, L.A.T. Bauerdick, A. Beretvas, J. Berryhill,P.C. Bhat, G. Bolla, K. Burkett, J.N. Butler, H.W.K. Cheung, F. Chlebana, S. Cihangir, V.D. Elvira,I. Fisk, J. Freeman, E. Gottschalk, L. Gray, D. Green, S. Grunendahl, O. Gutsche, J. Hanlon,D. Hare, R.M. Harris, J. Hirschauer, B. Hooberman, Z. Hu, S. Jindariani, M. Johnson, U. Joshi,A.W. Jung, B. Klima, B. Kreis, S. Kwan†, S. Lammel, J. Linacre, D. Lincoln, R. Lipton,
24 A The CMS Collaboration
T. Liu, R. Lopes De Sa, J. Lykken, K. Maeshima, J.M. Marraffino, V.I. Martinez Outschoorn,S. Maruyama, D. Mason, P. McBride, P. Merkel, K. Mishra, S. Mrenna, S. Nahn, C. Newman-Holmes, V. O’Dell, K. Pedro, O. Prokofyev, G. Rakness, E. Sexton-Kennedy, A. Soha,W.J. Spalding, L. Spiegel, L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger, E.W. Vaandering,C. Vernieri, M. Verzocchi, R. Vidal, H.A. Weber, A. Whitbeck, F. Yang, H. Yin
University of Florida, Gainesville, USAD. Acosta, P. Avery, P. Bortignon, D. Bourilkov, A. Carnes, M. Carver, D. Curry, S. Das, G.P. DiGiovanni, R.D. Field, M. Fisher, I.K. Furic, J. Hugon, J. Konigsberg, A. Korytov, J.F. Low,P. Ma, K. Matchev, H. Mei, P. Milenovic62, G. Mitselmakher, L. Muniz, D. Rank, R. Rossin,L. Shchutska, M. Snowball, D. Sperka, J. Wang, S. Wang, J. Yelton
Florida International University, Miami, USAS. Hewamanage, S. Linn, P. Markowitz, G. Martinez, J.L. Rodriguez
Florida State University, Tallahassee, USAA. Ackert, J.R. Adams, T. Adams, A. Askew, J. Bochenek, B. Diamond, J. Haas, S. Hagopian,V. Hagopian, K.F. Johnson, A. Khatiwada, H. Prosper, V. Veeraraghavan, M. Weinberg
Florida Institute of Technology, Melbourne, USAV. Bhopatkar, M. Hohlmann, H. Kalakhety, D. Mareskas-palcek, T. Roy, F. Yumiceva
University of Illinois at Chicago (UIC), Chicago, USAM.R. Adams, L. Apanasevich, D. Berry, R.R. Betts, I. Bucinskaite, R. Cavanaugh, O. Evdokimov,L. Gauthier, C.E. Gerber, D.J. Hofman, P. Kurt, C. O’Brien, I.D. Sandoval Gonzalez,C. Silkworth, P. Turner, N. Varelas, Z. Wu, M. Zakaria
The University of Iowa, Iowa City, USAB. Bilki63, W. Clarida, K. Dilsiz, S. Durgut, R.P. Gandrajula, M. Haytmyradov, V. Khristenko,J.-P. Merlo, H. Mermerkaya64, A. Mestvirishvili, A. Moeller, J. Nachtman, H. Ogul, Y. Onel,F. Ozok53, A. Penzo, C. Snyder, P. Tan, E. Tiras, J. Wetzel, K. Yi
Johns Hopkins University, Baltimore, USAI. Anderson, B.A. Barnett, B. Blumenfeld, D. Fehling, L. Feng, A.V. Gritsan, P. Maksimovic,C. Martin, K. Nash, M. Osherson, M. Swartz, M. Xiao, Y. Xin
The University of Kansas, Lawrence, USAP. Baringer, A. Bean, G. Benelli, C. Bruner, J. Gray, R.P. Kenny III, D. Majumder, M. Malek,M. Murray, D. Noonan, S. Sanders, R. Stringer, Q. Wang, J.S. Wood
Kansas State University, Manhattan, USAI. Chakaberia, A. Ivanov, K. Kaadze, S. Khalil, M. Makouski, Y. Maravin, A. Mohammadi,L.K. Saini, N. Skhirtladze, I. Svintradze, S. Toda
Lawrence Livermore National Laboratory, Livermore, USAD. Lange, F. Rebassoo, D. Wright
University of Maryland, College Park, USAC. Anelli, A. Baden, O. Baron, A. Belloni, B. Calvert, S.C. Eno, C. Ferraioli, J.A. Gomez,N.J. Hadley, S. Jabeen, R.G. Kellogg, T. Kolberg, J. Kunkle, Y. Lu, A.C. Mignerey, Y.H. Shin,A. Skuja, M.B. Tonjes, S.C. Tonwar
Massachusetts Institute of Technology, Cambridge, USAA. Apyan, R. Barbieri, A. Baty, K. Bierwagen, S. Brandt, W. Busza, I.A. Cali, Z. Demiragli, L. DiMatteo, G. Gomez Ceballos, M. Goncharov, D. Gulhan, G.M. Innocenti, M. Klute, D. Kovalskyi,
25
Y.S. Lai, Y.-J. Lee, A. Levin, P.D. Luckey, C. Mcginn, C. Mironov, X. Niu, C. Paus, D. Ralph,C. Roland, G. Roland, J. Salfeld-Nebgen, G.S.F. Stephans, K. Sumorok, M. Varma, D. Velicanu,J. Veverka, J. Wang, T.W. Wang, B. Wyslouch, M. Yang, V. Zhukova
University of Minnesota, Minneapolis, USAB. Dahmes, A. Finkel, A. Gude, P. Hansen, S. Kalafut, S.C. Kao, K. Klapoetke, Y. Kubota,Z. Lesko, J. Mans, S. Nourbakhsh, N. Ruckstuhl, R. Rusack, N. Tambe, J. Turkewitz
University of Mississippi, Oxford, USAJ.G. Acosta, S. Oliveros
University of Nebraska-Lincoln, Lincoln, USAE. Avdeeva, K. Bloom, S. Bose, D.R. Claes, A. Dominguez, C. Fangmeier, R. Gonzalez Suarez,R. Kamalieddin, J. Keller, D. Knowlton, I. Kravchenko, J. Lazo-Flores, F. Meier, J. Monroy,F. Ratnikov, J.E. Siado, G.R. Snow
State University of New York at Buffalo, Buffalo, USAM. Alyari, J. Dolen, J. George, A. Godshalk, I. Iashvili, J. Kaisen, A. Kharchilava, A. Kumar,S. Rappoccio
Northeastern University, Boston, USAG. Alverson, E. Barberis, D. Baumgartel, M. Chasco, A. Hortiangtham, A. Massironi,D.M. Morse, D. Nash, T. Orimoto, R. Teixeira De Lima, D. Trocino, R.-J. Wang, D. Wood,J. Zhang
Northwestern University, Evanston, USAK.A. Hahn, A. Kubik, N. Mucia, N. Odell, B. Pollack, A. Pozdnyakov, M. Schmitt, S. Stoynev,K. Sung, M. Trovato, M. Velasco, S. Won
University of Notre Dame, Notre Dame, USAA. Brinkerhoff, N. Dev, M. Hildreth, C. Jessop, D.J. Karmgard, N. Kellams, K. Lannon, S. Lynch,N. Marinelli, F. Meng, C. Mueller, Y. Musienko35, T. Pearson, M. Planer, A. Reinsvold, R. Ruchti,G. Smith, N. Valls, M. Wayne, M. Wolf, A. Woodard
The Ohio State University, Columbus, USAL. Antonelli, J. Brinson, B. Bylsma, L.S. Durkin, S. Flowers, A. Hart, C. Hill, R. Hughes,K. Kotov, T.Y. Ling, B. Liu, W. Luo, D. Puigh, M. Rodenburg, B.L. Winer, H.W. Wulsin
Princeton University, Princeton, USAO. Driga, P. Elmer, J. Hardenbrook, P. Hebda, S.A. Koay, P. Lujan, D. Marlow, T. Medvedeva,M. Mooney, J. Olsen, C. Palmer, P. Piroue, X. Quan, H. Saka, D. Stickland, C. Tully, J.S. Werner,A. Zuranski
University of Puerto Rico, Mayaguez, USAS. Malik
Purdue University, West Lafayette, USAV.E. Barnes, D. Benedetti, D. Bortoletto, L. Gutay, M.K. Jha, M. Jones, K. Jung, M. Kress,D.H. Miller, N. Neumeister, F. Primavera, B.C. Radburn-Smith, X. Shi, I. Shipsey, D. Silvers,J. Sun, A. Svyatkovskiy, F. Wang, W. Xie, L. Xu, J. Zablocki
Purdue University Calumet, Hammond, USAN. Parashar, J. Stupak
26 A The CMS Collaboration
Rice University, Houston, USAA. Adair, B. Akgun, Z. Chen, K.M. Ecklund, F.J.M. Geurts, M. Guilbaud, W. Li, B. Michlin,M. Northup, B.P. Padley, R. Redjimi, J. Roberts, J. Rorie, Z. Tu, J. Zabel
University of Rochester, Rochester, USAB. Betchart, A. Bodek, P. de Barbaro, R. Demina, Y. Eshaq, T. Ferbel, M. Galanti, A. Garcia-Bellido, P. Goldenzweig, J. Han, A. Harel, O. Hindrichs, A. Khukhunaishvili, G. Petrillo,M. Verzetti
The Rockefeller University, New York, USAL. Demortier
Rutgers, The State University of New Jersey, Piscataway, USAS. Arora, A. Barker, J.P. Chou, C. Contreras-Campana, E. Contreras-Campana, D. Duggan,D. Ferencek, Y. Gershtein, R. Gray, E. Halkiadakis, D. Hidas, E. Hughes, S. Kaplan,R. Kunnawalkam Elayavalli, A. Lath, S. Panwalkar, M. Park, S. Salur, S. Schnetzer, D. Sheffield,S. Somalwar, R. Stone, S. Thomas, P. Thomassen, M. Walker
University of Tennessee, Knoxville, USAM. Foerster, G. Riley, K. Rose, S. Spanier, A. York
Texas A&M University, College Station, USAO. Bouhali65, A. Castaneda Hernandez, M. Dalchenko, M. De Mattia, A. Delgado, S. Dildick,R. Eusebi, W. Flanagan, J. Gilmore, T. Kamon66, V. Krutelyov, R. Montalvo, R. Mueller,I. Osipenkov, Y. Pakhotin, R. Patel, A. Perloff, J. Roe, A. Rose, A. Safonov, A. Tatarinov,K.A. Ulmer2
Texas Tech University, Lubbock, USAN. Akchurin, C. Cowden, J. Damgov, C. Dragoiu, P.R. Dudero, J. Faulkner, S. Kunori,K. Lamichhane, S.W. Lee, T. Libeiro, S. Undleeb, I. Volobouev
Vanderbilt University, Nashville, USAE. Appelt, A.G. Delannoy, S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, Y. Mao,A. Melo, P. Sheldon, B. Snook, S. Tuo, J. Velkovska, Q. Xu
University of Virginia, Charlottesville, USAM.W. Arenton, S. Boutle, B. Cox, B. Francis, J. Goodell, R. Hirosky, A. Ledovskoy, H. Li, C. Lin,C. Neu, E. Wolfe, J. Wood, F. Xia
Wayne State University, Detroit, USAC. Clarke, R. Harr, P.E. Karchin, C. Kottachchi Kankanamge Don, P. Lamichhane, J. Sturdy
University of Wisconsin, Madison, USAD.A. Belknap, D. Carlsmith, M. Cepeda, A. Christian, S. Dasu, L. Dodd, S. Duric, E. Friis,B. Gomber, R. Hall-Wilton, M. Herndon, A. Herve, P. Klabbers, A. Lanaro, A. Levine, K. Long,R. Loveless, A. Mohapatra, I. Ojalvo, T. Perry, G.A. Pierro, G. Polese, I. Ross, T. Ruggles,T. Sarangi, A. Savin, A. Sharma, N. Smith, W.H. Smith, D. Taylor, N. Woods
†: Deceased1: Also at Vienna University of Technology, Vienna, Austria2: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland3: Also at State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing,China4: Also at Institut Pluridisciplinaire Hubert Curien, Universite de Strasbourg, Universite deHaute Alsace Mulhouse, CNRS/IN2P3, Strasbourg, France
27
5: Also at National Institute of Chemical Physics and Biophysics, Tallinn, Estonia6: Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University,Moscow, Russia7: Also at Universidade Estadual de Campinas, Campinas, Brazil8: Also at Centre National de la Recherche Scientifique (CNRS) - IN2P3, Paris, France9: Also at Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France10: Also at Joint Institute for Nuclear Research, Dubna, Russia11: Also at Zewail City of Science and Technology, Zewail, Egypt12: Also at Helwan University, Cairo, Egypt13: Also at British University in Egypt, Cairo, Egypt14: Now at Ain Shams University, Cairo, Egypt15: Also at Universite de Haute Alsace, Mulhouse, France16: Also at Tbilisi State University, Tbilisi, Georgia17: Also at Ilia State University, Tbilisi, Georgia18: Also at Brandenburg University of Technology, Cottbus, Germany19: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary20: Also at Eotvos Lorand University, Budapest, Hungary21: Also at University of Debrecen, Debrecen, Hungary22: Also at Wigner Research Centre for Physics, Budapest, Hungary23: Also at University of Visva-Bharati, Santiniketan, India24: Now at King Abdulaziz University, Jeddah, Saudi Arabia25: Also at University of Ruhuna, Matara, Sri Lanka26: Also at Isfahan University of Technology, Isfahan, Iran27: Also at University of Tehran, Department of Engineering Science, Tehran, Iran28: Also at Plasma Physics Research Center, Science and Research Branch, Islamic AzadUniversity, Tehran, Iran29: Also at Laboratori Nazionali di Legnaro dell’INFN, Legnaro, Italy30: Also at Universita degli Studi di Siena, Siena, Italy31: Also at Purdue University, West Lafayette, USA32: Also at International Islamic University of Malaysia, Kuala Lumpur, Malaysia33: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia34: Also at Consejo Nacional de Ciencia y Tecnologıa, Mexico city, Mexico35: Also at Institute for Nuclear Research, Moscow, Russia36: Also at St. Petersburg State Polytechnical University, St. Petersburg, Russia37: Also at National Research Nuclear University ’Moscow Engineering PhysicsInstitute’ (MEPhI), Moscow, Russia38: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia39: Also at Facolta Ingegneria, Universita di Roma, Roma, Italy40: Also at National Technical University of Athens, Athens, Greece41: Also at Scuola Normale e Sezione dell’INFN, Pisa, Italy42: Also at University of Athens, Athens, Greece43: Also at Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland44: Also at Institute for Theoretical and Experimental Physics, Moscow, Russia45: Also at Albert Einstein Center for Fundamental Physics, Bern, Switzerland46: Also at Adiyaman University, Adiyaman, Turkey47: Also at Mersin University, Mersin, Turkey48: Also at Cag University, Mersin, Turkey49: Also at Piri Reis University, Istanbul, Turkey50: Also at Gaziosmanpasa University, Tokat, Turkey
28 A The CMS Collaboration
51: Also at Ozyegin University, Istanbul, Turkey52: Also at Izmir Institute of Technology, Izmir, Turkey53: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey54: Also at Marmara University, Istanbul, Turkey55: Also at Kafkas University, Kars, Turkey56: Also at Yildiz Technical University, Istanbul, Turkey57: Also at Hacettepe University, Ankara, Turkey58: Also at Rutherford Appleton Laboratory, Didcot, United Kingdom59: Also at School of Physics and Astronomy, University of Southampton, Southampton,United Kingdom60: Also at Instituto de Astrofısica de Canarias, La Laguna, Spain61: Also at Utah Valley University, Orem, USA62: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences,Belgrade, Serbia63: Also at Argonne National Laboratory, Argonne, USA64: Also at Erzincan University, Erzincan, Turkey65: Also at Texas A&M University at Qatar, Doha, Qatar66: Also at Kyungpook National University, Daegu, Korea
