EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN)

CERN-PH-EP/2011-0342011/07/01

CMS-BPH-10-005

Measurement of the B0 Production Cross Section in ppCollisions at

√s = 7 TeV

The CMS Collaboration∗

Abstract

Measurements of the differential production cross sections dσ/dpBT and dσ/dyB for

B0 mesons produced in pp collisions at√

s = 7 TeV are presented. The dataset usedwas collected by the CMS experiment at the LHC and corresponds to an integratedluminosity of 40 pb−1. The production cross section is measured from B0 meson de-cays reconstructed in the exclusive final state J/ψ K0

S, with the subsequent decaysJ/ψ → µ+µ− and K0

S → π+π−. The total cross section for pBT > 5 GeV and

∣∣yB∣∣ < 2.2

is measured to be 33.2± 2.5± 3.5 µb, where the first uncertainty is statistical and thesecond is systematic.

Submitted to Physical Review Letters

∗See Appendix 1 for the list of collaboration members

arX

iv:1

104.

2892

v2 [

hep-

ex]

30

Jun

2011

1

Cross sections for heavy quark production in hard scattering interactions have been studied atpp colliders at center-of-mass energies from 630 GeV [1] to 1.96 TeV [2–4] and in p−nucleuscollisons with beam energies from 800 to 920 GeV [5]. The expected cross sections can be cal-culated in perturbative Quantum Chromodynamics. The comparison between data and pre-dictions provides a critical test of next-to-leading order (NLO) calculations [6]. Considerableprogress has been achieved in understanding heavy quark production at Tevatron energies,largely resolving earlier discrepancies [7], but substantial theoretical uncertainties remain dueto the dependence on the renormalization and factorization scales. Measurements of b-hadronproduction at 7 TeV provided by the Large Hadron Collider (LHC) [8–10] represent a test at anew center-of-mass energy of theoretical approaches that aim to describe heavy flavor produc-tion [11, 12].

This Letter presents the first measurement of the B0 cross section in pp collisions at√

s = 7 TeV.Events with B0 mesons reconstructed from their decays to the final state J/ψ K0

S, with J/ψ →µ+µ− and K0

S → π+π−, are used to measure dσ/dpBT, dσ/dyB, and the integrated cross section

for transverse momentum pBT > 5 GeV and rapidity

∣∣yB∣∣ < 2.2, where y is defined as 1

2 ln E+pLE−pL

,E is the particle energy, and pL is the particle momentum along the counterclockwise beamdirection. As the B0 and B

0are indistinguishable in this analysis, both mesons are referred to

as B0 for the purposes of reconstruction and the final results are divided by two to obtain anaverage.

The data sample collected by the Compact Muon Solenoid (CMS) detector at the LHC corre-sponds to an integrated luminosity of 39.6± 1.6 pb−1 and represents the entire 2010 dataset. Adetailed description of the detector may be found elsewhere [13]. The main detector compo-nents used in this analysis are the silicon tracker and the muon systems.

The silicon tracker measures charged particles within the pseudorapidity range |η| < 2.5,where η = − ln tan ( θ

2 ) and θ is the polar angle of the track relative to the counterclockwisebeam direction. It consists of 1440 silicon pixel and 15 148 silicon strip detector modules andis located in the 3.8 T field of the superconducting solenoid. It provides an impact parameterresolution of ∼ 15 µm and a pT resolution of about 1.5% for particles with transverse momentaup to 100 GeV. Muons are measured in the pseudorapidity range |η| < 2.4, with detectionplanes made using three technologies: drift tubes, cathode strip chambers, and resistive platechambers.

Events are selected by a trigger requiring two muons without any explicit requirement on themuon momentum. The muon candidates are fully reconstructed offline, combining informa-tion from the silicon tracker and muon detectors, and are required to be within the followingkinematic acceptance region: pµ

T > 3.3 GeV for |ηµ| < 1.3; total momentum pµ > 2.9 GeV for1.3 < |ηµ| < 2.2; and pµ

T > 0.8 GeV for 2.2 < |ηµ| < 2.4. Opposite-sign muon pairs are fitto a common vertex to form J/ψ candidates, which are required to be within 150 MeV of theworld-average J/ψ mass [14].

The K0S candidates are formed by fitting oppositely charged tracks reconstructed with the CMS

tracking algorithm [15] to a common vertex. Each track is required to have at least 6 hits inthe silicon tracker, a normalized χ2 < 5, and a transverse impact parameter with respect tothe luminous region greater than 0.5 times its uncertainty. The reconstructed K0

S decay vertexmust have a normalized χ2 < 7 and a transverse separation from the luminous region at least 5times larger than the uncertainty on the separation. The π+π− invariant mass mK0

Sis required

to satisfy 478 < mK0S< 518 MeV, and the reconstructed mass distribution is found to be in good

agreement with the world-average value [14].

2

The B0 candidates are formed by combining a J/ψ candidate with a K0S candidate. A kinematic

fit is performed with the two muons and the K0S candidate, in which the invariant masses of

the J/ψ and K0S candidates are constrained to their world-average values [14]. The B0 vertex

fit confidence level is required to be greater than 1% and the reconstructed B0 mass mB mustsatisfy 4.9 < mB < 5.7 GeV. When more than one candidate in a single event passes all theselection criteria, only the candidate with the highest B0 vertex fit confidence level is retained,which results in the correct choice 99% of the time in simulated events containing a true signalcandidate. A total of 23 174 B0 candidates pass all selection criteria.

The efficiency of the B0 reconstruction is computed with a combination of techniques usingthe data and large samples of fully simulated signal events generated by PYTHIA 6.422 [16],decayed by EVTGEN [17], and simulated by GEANT4 [18]. The trigger and muon-reconstructionefficiencies are obtained from a large sample of inclusive J/ψ → µ+µ− decays in data using atechnique similar to that described in Ref. [19], where one muon is identified with stringentquality requirements, and the second muon is identified using information either exclusivelyfrom the tracker (to measure the trigger and muon-identification efficiencies), or from the muonsystem (to measure the silicon tracking efficiency). Since the dimuon efficiencies are calculatedas the product of the measured single muon efficiencies, a correction (1–6%), obtained from thesimulation, is applied to take into account efficiency correlations between the two muons. Theprobabilities for the muons to lie within the kinematic acceptance region and for the B0 and K0

Scandidates to pass the selection requirements are determined from the simulated events. Tominimize the effect of the PYTHIA modeling of the pB

T and∣∣yB∣∣ distributions on the efficiency

calculation, the simulated events are reweighted to match the kinematic distributions observedin the data. The efficiencies for hadron-track reconstruction [20], K0

S reconstruction [21], and forfulfilling the vertex quality requirement are found to be consistent between data and simulationwithin the available precision (up to 5%).

The total efficiency of this selection, defined as the fraction of B0 → J/ψ K0S decays produced

with pBT > 5 GeV and

∣∣yB∣∣ < 2.2 that pass all criteria, is 1.7%. The efficiency ranges from

0.7% for pBT ∼ 5 GeV, to 11.4% for pB

T > 24 GeV, with roughly equal losses due to the dimuonkinematic acceptance, the dimuon trigger, and the K0

S reconstruction.

The proper decay length of each selected B0 candidate is calculated as ct = (mB/pBT)Lxy, where

the transverse decay length Lxy is the vector~s pointing from the primary vertex [15] to the B0

vertex projected onto the B0 transverse momentum vector: Lxy = (~s · ~pBT)/∣∣~pB

T

∣∣.Backgrounds are dominated by prompt and non-prompt J/ψ production, with non-prompt con-tributions from sources peaking and nonpeaking in mB, as shown in Fig. 1. In particular, mis-reconstructed b-hadron decays to final states with a J/ψ, such as B → J/ψK∗(892), producea broadly peaking structure in the region mB < 5.2 GeV. A study of the dimuon invariantmass distribution confirms that the contamination from events containing a misidentified J/ψis negligible after all selection criteria have been applied.

The signal yields in each pBT and

∣∣yB∣∣ bin are obtained using an unbinned extended maximum-

likelihood fit to mB and ct. The likelihood for event j is obtained by summing the product ofyield ni and probability density Pi for each of the signal and background hypotheses i. Fourindividual components are considered: signal events, prompt J/ψ events, non-prompt b→ J/ψevents that peak in mB (peaking), and non-prompt b → J/ψ events that do not peak in mB(nonpeaking). The extended likelihood function is the product of likelihoods for all events:

L = exp

(−

4

∑i=1

ni

)∏

j

[4

∑i=1

niPi(mB; ~αi)Pi(ct; ~βi)

]. (1)

3

The probability density functions (PDFs), Pi, with shape parameters ~αi for mB and ~βi for ct,are evaluated separately for each of the i fit components. The yields ni are determined bymaximizing L with respect to the yields and a subset of the PDF parameters.

The PDF shapes are described below with the parameters obtained from data when possible.The mB PDFs are as follows: the sum of two Gaussian functions for the signal; exponential func-tions for the prompt and nonpeaking backgrounds; and a sum of three Gaussian functions forthe peaking background. The resolution on mB for correctly reconstructed signal events fromsimulation is approximately 20 MeV. The ct PDFs are as follows: a single exponential functionconvolved with the resolution function to describe the signal and peaking background com-ponents, where the lifetimes are allowed to be different; the sum of two exponential functionsconvolved with the resolution function for the nonpeaking component; and the pure resolu-tion function for the prompt J/ψ component. The resolution function, a sum of two Gaussianfunctions, is common for signal and background and is measured in data to have an averageresolution of 71 µm.

The fit proceeds in several steps such that all background shapes are obtained directly fromdata, except for the peaking component which is taken from simulation, as are the signal mBshapes. This technique relies on the assumption that in the region 5.4 < mB < 5.7 GeV (side-band) there are only two contributions: prompt J/ψ and nonpeaking background. To obtainthe effective lifetime distribution of the nonpeaking background, the mB and ct distributionsin the mB sideband region are fit simultaneously for events in the inclusive B0 sample definedby pB

T > 5 GeV and∣∣yB∣∣ < 2.2. In the second step, the signal B0 lifetime in the inclusive

sample is determined by fitting ct and mB simultaneously in the full mB range. The result,cτ = 479± 22 µm (statistical uncertainty only), is in agreement with the world-average value,457± 3 µm [14]. With the effective lifetimes for signal and non-prompt background fixed, thesignal and background yields are fit in each bin of pB

T and∣∣yB∣∣, together with the parameters

describing the ct resolution and the shapes of the prompt and nonpeaking components in mB.

The accuracy and robustness of the fit strategy were demonstrated by performing a large set ofpseudo-experiments, with each one corresponding to the yields observed in data, where signaland background events were generated randomly from the PDFs in each bin. No significantbiases were observed on the yields, and the statistical precision of the test was taken as thesystematic uncertainty due to potential biases in the fit method. The fit uncertainties were alsoobserved to be estimated properly.

The fitted signal yields in each bin of pBT and

∣∣yB∣∣ are summarized in Table 1. Figure 1 shows

the fit projections for mB and ct from the inclusive sample with pBT > 5 GeV and

∣∣yB∣∣ < 2.2. The

total number of signal events is 809± 39, where the uncertainty is statistical only.

The differential cross section is calculated in bins of pBT as

dσ(pp→ B0X)

dpBT

=nsig

2 · ε · B · L · ∆pBT

, (2)

and similarly for∣∣yB∣∣, where nsig is the fitted number of signal events in the given bin, ε is the

efficiency for a B0 meson to pass all the selection criteria, L is the integrated luminosity, ∆pBT is

the bin size, and B is the product of branching fractions B(B0 → J/ψ K0S) = (4.36± 0.16)× 10−4,

B(J/ψ → µ+µ−) = (5.93± 0.06)× 10−2, and B(K0S → π+π−) = 0.6920± 0.0005 [14]. The ad-

ditional factor of two in the denominator accounts for our choice of quoting the cross sectionfor B0 production only, while nsig includes both B0 and B

0. The efficiencies are calculated sepa-

rately for each bin, always considering only mesons produced with∣∣yB∣∣ < 2.2 (pB

T > 5 GeV) for

4

(GeV)Bm4.9 5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

Can

dida

tes

/ ( 0

.025

GeV

)

0

200

400

600

800

1000

1200

(GeV)Bm4.9 5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

Can

dida

tes

/ ( 0

.025

GeV

)

0

200

400

600

800

1000

1200

CMS dataΨPrompt J/

+ peaking B + non-peaking B + signal(a)

= 7 TeVsCMS -1L = 40 pb

ct (cm)-0.05 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

Can

dida

tes

/ ( 0

.004

5 cm

)

-110

1

10

210

310

ct (cm)-0.05 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

Can

dida

tes

/ ( 0

.004

5 cm

)

-110

1

10

210

310

= 7 TeVsCMS -1L = 40 pb

CMS dataΨPrompt J/

+ peaking B + non-peaking B + signal

(b)

Figure 1: Projections of the fit results in (a) mB and (b) ct for pBT > 5 GeV and

∣∣yB∣∣ < 2.2. The

curves in each plot are as follows: the sum of all contributions (blue solid line); the prompt J/ψ(green dotted); the sum of the prompt J/ψ and peaking background (red dashed), and the sumof all backgrounds (purple dot-dashed).

[GeV]T

p0B5 10 15 20 25 30 35 40

b/G

eV)

µ|<

2.2)

(B

X;

|y0

B→

(pp

T

/dp

σd

-210

-110

1

10CMS data

Pythia 6 (MSEL = 1, CTEQ6L1, Z2)

= 4.75 GeV)b

MC@NLO (CTEQ6M, m

MC@NLO total uncertainty

= 7 TeVsCMS -1L = 40 pb

(a)

Branching fraction (3.8%) and Luminosity (4%) uncertainties not shown

)-π+π(s

) K-µ+µ(ψ J/→ 0B

|y|0B0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2

b)

µ>5

GeV

) (

B TX

; p

0 B

→/d

y(p

p

σd

0

2

4

6

8

10

12

14

16

18CMS data

Pythia 6 (MSEL = 1, CTEQ6L1, Z2)

= 4.75 GeV)b

MC@NLO (CTEQ6M, m

MC@NLO total uncertainty

= 7 TeVsCMS -1L = 40 pb

(b)

Branching fraction (3.8%) and Luminosity (4%) uncertainties not shown

)-π+π(s

) K-µ+µ(ψ J/→ 0B

Figure 2: Measured differential cross sections (a) dσ/dpBT and (b) dσ/dyB compared to the theo-

retical predictions. The inner error bars correspond to the statistical uncertainties and the outererror bars represents the uncorrelated systematic uncertainties added in quadrature to the sta-tistical uncertainties. Overall uncertainties of 4% for the luminosity and 3.8% for the branchingfractions are not shown. The solid and dashed (blue) lines are the MC@NLO prediction and itsuncertainty, respectively. The dotted (red) line is the PYTHIA prediction.

pBT (∣∣yB∣∣) bins, and take into account bin-to-bin migrations (< 1%) due to the resolution on the

measured pBT and

∣∣yB∣∣.

The cross section is affected by systematic uncertainties on the signal yield and efficiencies,which are uncorrelated bin-to-bin and can affect the shapes of the distributions, and by un-certainties on the branching fractions and luminosity, which are common to all bins and onlyaffect the overall normalization. The uncertainty on the signal yield arises from potential fitbiases and imperfect knowledge of the PDF parameters (4–7%), and from effects of final-stateradiation and mismeasured track momenta on the signal shape in mB (1%). Uncertainties onthe efficiencies arise from the trigger (2–3%), muon identification (1%), muon tracking (1%),K0

S (5%) and B0 (3%) candidate selection requirements, acceptance (2–3%), dimuon correlations(1–5%) and pB

T and∣∣yB∣∣ mismeasurement (1%). The first five efficiency uncertainties are de-

termined directly from data, while the last three are determined by simulation. The largestuncertainties on the efficiency arrise from the K0

S reconstruction, which is dominated by the

5

Table 1: Signal yield nsig, efficiency ε, and measured differential cross sections dσ/dpBT and

dσ/dyB, compared to the MC@NLO [22] and PYTHIA [16] predictions. The uncertainties inthe measured cross sections are statistical and systematic, respectively, excluding the commonluminosity (4%) and branching fraction (3.8%) uncertainties. The uncertainties on the signalyields are statistical only, while those on the efficiencies are systematic.

pBT (GeV) nsig ε (%) dσ/dpB

T (µb/GeV) MC@NLO PYTHIA

5− 10 240± 23 0.65± 0.05 5.20± 0.50± 0.59 3.66 7.4210− 13 169± 17 3.32± 0.28 1.196± 0.121± 0.117 1.13 2.1413− 17 193± 16 6.37± 0.51 0.535± 0.045± 0.051 0.49 0.8317− 24 138± 13 9.60± 0.76 0.145± 0.014± 0.014 0.15 0.2424− 40 70± 9 11.40± 1.04 0.027± 0.003± 0.003 0.025 0.035

|yB| nsig ε (%) dσ/dyB (µb) MC@NLO PYTHIA

0.0− 0.5 145± 14 1.34± 0.10 7.63± 0.74± 0.76 6.21 12.410.5− 1.0 141± 15 1.38± 0.10 7.20± 0.75± 0.71 6.14 12.011.0− 1.4 167± 17 1.93± 0.15 7.61± 0.77± 0.83 5.81 11.241.4− 1.8 229± 21 2.51± 0.21 8.06± 0.74± 0.89 5.38 10.361.8− 2.2 128± 17 1.69± 0.14 6.71± 0.87± 0.80 4.81 9.26

displaced hadronic track efficiency and is measured by comparing the reconstructed K0S life-

time with the known value, and the dimuon correlation uncertainty, which is taken as 100% ofthe correction applied to account for the correlations. The difference between the kinematicallyreweighted and unreweighted results (3–5%) is taken as an additional systematic uncertainty.The bin-to-bin systematic uncertainty is computed as the sum in quadrature of the individualuncertainties, and is summarized in Table 1. In addition, there are normalization uncertaintiesof 4% from the luminosity measurement and of 3.8% from the branching fractions [14].

The differential cross sections as functions of pBT and

∣∣yB∣∣ are shown in Fig. 2 and Table 1.

They are compared to the predictions of MC@NLO [22] using a b-quark mass mb of 4.75 GeV,

renormalization and factorization scales µ =√

m2b + p2

T, and the CTEQ6M parton distributionfunctions [23]. The uncertainty on the predicted cross section is calculated by independentlyvarying the renormalization and factorization scales by factors of two, mb by±0.25 GeV, and byusing the CTEQ6.6 parton distribution functions. For reference, the prediction of PYTHIA [16] isalso included, using a b-quark mass of 4.80 GeV, CTEQ6L1 parton distribution functions [23],and the Z2 tune [24] to simulate the underlying event. The measured pT spectrum falls slightlyfaster than predicted by MC@NLO, while the y spectrum is measured to be flatter than thePYTHIA prediction and in agreement with the MC@NLO prediction within uncertainties. Theintegrated cross section for pB

T > 5 GeV and∣∣yB∣∣ < 2.2 is calculated as the sum over all pT bins,

without an upper limit for the highest pT bin, to be 33.2± 2.5± 3.5 µb, where the first uncer-tainty is statistical and the second is systematic. The result is compatible with the predictionfrom MC@NLO (25.2+9.6

−6.2 µb) and below the prediction from PYTHIA (49.1 µb).

In summary, the first measurements of the differential cross sections dσ/dpBT and dσ/dyB for

B0 mesons produced in pp collisions at√

s = 7 TeV have been presented using the decayB0 → J/ψ K0

S. The measurements cover a range in pBT from 5 GeV to more than 30 GeV, and

the rapidity range∣∣yB∣∣ < 2.2. The total cross section in this kinematic region lies between

the central values of the MC@NLO and PYTHIA predictions, with a rapidity distribution that is

6

flatter than PYTHIA. It is also in agreement within uncertainties with the measured B+ crosssection [9].

We wish to congratulate our colleagues in the CERN accelerator departments for the excellentperformance of the LHC machine. We thank the technical and administrative staff at CERN andother CMS institutes, and acknowledge support from: FMSR (Austria); FNRS and FWO (Bel-gium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, andNSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sci-ences and NICPB (Estonia); Academy of Finland, ME, and HIP (Finland); CEA and CNRS/IN2P3(France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary);DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS(Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR(Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST andMAE (Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzer-land); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF(USA).

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1 The CMS CollaborationYerevan Physics Institute, Yerevan, ArmeniaS. Chatrchyan, V. Khachatryan, A.M. Sirunyan, A. Tumasyan

Institut fur Hochenergiephysik der OeAW, Wien, AustriaW. Adam, T. Bergauer, M. Dragicevic, J. Ero, C. Fabjan, M. Friedl, R. Fruhwirth, V.M. Ghete,J. Hammer1, S. Hansel, M. Hoch, N. Hormann, J. Hrubec, M. Jeitler, G. Kasieczka,W. Kiesenhofer, M. Krammer, D. Liko, I. Mikulec, M. Pernicka, H. Rohringer, R. Schofbeck,J. Strauss, F. Teischinger, P. Wagner, W. Waltenberger, G. Walzel, E. Widl, C.-E. Wulz

National Centre for Particle and High Energy Physics, Minsk, BelarusV. Mossolov, N. Shumeiko, J. Suarez Gonzalez

Universiteit Antwerpen, Antwerpen, BelgiumL. Benucci, E.A. De Wolf, X. Janssen, T. Maes, L. Mucibello, S. Ochesanu, B. Roland, R. Rougny,M. Selvaggi, H. Van Haevermaet, P. Van Mechelen, N. Van Remortel

Vrije Universiteit Brussel, Brussel, BelgiumF. Blekman, S. Blyweert, J. D’Hondt, O. Devroede, R. Gonzalez Suarez, A. Kalogeropoulos,J. Maes, M. Maes, W. Van Doninck, P. Van Mulders, G.P. Van Onsem, I. Villella

Universite Libre de Bruxelles, Bruxelles, BelgiumO. Charaf, B. Clerbaux, G. De Lentdecker, V. Dero, A.P.R. Gay, G.H. Hammad, T. Hreus,P.E. Marage, L. Thomas, C. Vander Velde, P. Vanlaer

Ghent University, Ghent, BelgiumV. Adler, A. Cimmino, S. Costantini, M. Grunewald, B. Klein, J. Lellouch, A. Marinov,J. Mccartin, D. Ryckbosch, F. Thyssen, M. Tytgat, L. Vanelderen, P. Verwilligen, S. Walsh,N. Zaganidis

Universite Catholique de Louvain, Louvain-la-Neuve, BelgiumS. Basegmez, G. Bruno, J. Caudron, L. Ceard, E. Cortina Gil, J. De Favereau De Jeneret,C. Delaere1, D. Favart, A. Giammanco, G. Gregoire, J. Hollar, V. Lemaitre, J. Liao, O. Militaru,S. Ovyn, D. Pagano, A. Pin, K. Piotrzkowski, N. Schul

Universite de Mons, Mons, BelgiumN. Beliy, T. Caebergs, E. Daubie

Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, BrazilG.A. Alves, D. De Jesus Damiao, M.E. Pol, M.H.G. Souza

Universidade do Estado do Rio de Janeiro, Rio de Janeiro, BrazilW. Carvalho, E.M. Da Costa, C. De Oliveira Martins, S. Fonseca De Souza, L. Mundim,H. Nogima, V. Oguri, W.L. Prado Da Silva, A. Santoro, S.M. Silva Do Amaral, A. Sznajder,F. Torres Da Silva De Araujo

Instituto de Fisica Teorica, Universidade Estadual Paulista, Sao Paulo, BrazilF.A. Dias, T.R. Fernandez Perez Tomei, E. M. Gregores2, C. Lagana, F. Marinho,P.G. Mercadante2, S.F. Novaes, Sandra S. Padula

Institute for Nuclear Research and Nuclear Energy, Sofia, BulgariaN. Darmenov1, L. Dimitrov, V. Genchev1, P. Iaydjiev1, S. Piperov, M. Rodozov, S. Stoykova,G. Sultanov, V. Tcholakov, R. Trayanov, I. Vankov

10 1 The CMS Collaboration

University of Sofia, Sofia, BulgariaA. Dimitrov, R. Hadjiiska, A. Karadzhinova, V. Kozhuharov, L. Litov, M. Mateev, B. Pavlov,P. Petkov

Institute of High Energy Physics, Beijing, ChinaJ.G. Bian, G.M. Chen, H.S. Chen, C.H. Jiang, D. Liang, S. Liang, X. Meng, J. Tao, J. Wang,J. Wang, X. Wang, Z. Wang, H. Xiao, M. Xu, J. Zang, Z. Zhang

State Key Lab. of Nucl. Phys. and Tech., Peking University, Beijing, ChinaY. Ban, S. Guo, Y. Guo, W. Li, Y. Mao, S.J. Qian, H. Teng, L. Zhang, B. Zhu, W. Zou

Universidad de Los Andes, Bogota, ColombiaA. Cabrera, B. Gomez Moreno, A.A. Ocampo Rios, A.F. Osorio Oliveros, J.C. Sanabria

Technical University of Split, Split, CroatiaN. Godinovic, D. Lelas, K. Lelas, R. Plestina3, D. Polic, I. Puljak

University of Split, Split, CroatiaZ. Antunovic, M. Dzelalija

Institute Rudjer Boskovic, Zagreb, CroatiaV. Brigljevic, S. Duric, K. Kadija, S. Morovic

University of Cyprus, Nicosia, CyprusA. Attikis, M. Galanti, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis

Charles University, Prague, Czech RepublicM. Finger, M. Finger Jr.

Academy of Scientific Research and Technology of the Arab Republic of Egypt, EgyptianNetwork of High Energy Physics, Cairo, EgyptY. Assran4, S. Khalil5, M.A. Mahmoud6

National Institute of Chemical Physics and Biophysics, Tallinn, EstoniaA. Hektor, M. Kadastik, M. Muntel, M. Raidal, L. Rebane

Department of Physics, University of Helsinki, Helsinki, FinlandV. Azzolini, P. Eerola, G. Fedi

Helsinki Institute of Physics, Helsinki, FinlandS. Czellar, J. Harkonen, A. Heikkinen, V. Karimaki, R. Kinnunen, M.J. Kortelainen, T. Lampen,K. Lassila-Perini, S. Lehti, T. Linden, P. Luukka, T. Maenpaa, E. Tuominen, J. Tuominiemi,E. Tuovinen, D. Ungaro, L. Wendland

Lappeenranta University of Technology, Lappeenranta, FinlandK. Banzuzi, A. Korpela, T. Tuuva

Laboratoire d’Annecy-le-Vieux de Physique des Particules, IN2P3-CNRS, Annecy-le-Vieux,FranceD. Sillou

DSM/IRFU, CEA/Saclay, Gif-sur-Yvette, FranceM. Besancon, S. Choudhury, M. Dejardin, D. Denegri, B. Fabbro, J.L. Faure, F. Ferri, S. Ganjour,F.X. Gentit, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, E. Locci, J. Malcles,M. Marionneau, L. Millischer, J. Rander, A. Rosowsky, I. Shreyber, M. Titov, P. Verrecchia

11

Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, FranceS. Baffioni, F. Beaudette, L. Benhabib, L. Bianchini, M. Bluj7, C. Broutin, P. Busson, C. Charlot,T. Dahms, L. Dobrzynski, S. Elgammal, R. Granier de Cassagnac, M. Haguenauer, P. Mine,C. Mironov, C. Ochando, P. Paganini, D. Sabes, R. Salerno, Y. Sirois, C. Thiebaux, B. Wyslouch8,A. Zabi

Institut Pluridisciplinaire Hubert Curien, Universite de Strasbourg, Universite de HauteAlsace Mulhouse, CNRS/IN2P3, Strasbourg, FranceJ.-L. Agram9, J. Andrea, D. Bloch, D. Bodin, J.-M. Brom, M. Cardaci, E.C. Chabert, C. Collard,E. Conte9, F. Drouhin9, C. Ferro, J.-C. Fontaine9, D. Gele, U. Goerlach, S. Greder, P. Juillot,M. Karim9, A.-C. Le Bihan, Y. Mikami, P. Van Hove

Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique desParticules (IN2P3), Villeurbanne, FranceF. Fassi, D. Mercier

Universite de Lyon, Universite Claude Bernard Lyon 1, CNRS-IN2P3, Institut de PhysiqueNucleaire de Lyon, Villeurbanne, FranceC. Baty, S. Beauceron, N. Beaupere, M. Bedjidian, O. Bondu, G. Boudoul, D. Boumediene,H. Brun, R. Chierici, D. Contardo, P. Depasse, H. El Mamouni, J. Fay, S. Gascon, B. Ille, T. Kurca,T. Le Grand, M. Lethuillier, L. Mirabito, S. Perries, V. Sordini, S. Tosi, Y. Tschudi, P. Verdier

Institute of High Energy Physics and Informatization, Tbilisi State University, Tbilisi,GeorgiaD. Lomidze

RWTH Aachen University, I. Physikalisches Institut, Aachen, GermanyG. Anagnostou, M. Edelhoff, L. Feld, N. Heracleous, O. Hindrichs, R. Jussen, K. Klein, J. Merz,N. Mohr, A. Ostapchuk, A. Perieanu, F. Raupach, J. Sammet, S. Schael, D. Sprenger, H. Weber,M. Weber, B. Wittmer

RWTH Aachen University, III. Physikalisches Institut A, Aachen, GermanyM. Ata, W. Bender, E. Dietz-Laursonn, M. Erdmann, J. Frangenheim, T. Hebbeker,A. Hinzmann, K. Hoepfner, T. Klimkovich, D. Klingebiel, P. Kreuzer, D. Lanske†, C. Magass,M. Merschmeyer, A. Meyer, P. Papacz, H. Pieta, H. Reithler, S.A. Schmitz, L. Sonnenschein,J. Steggemann, D. Teyssier, M. Tonutti

RWTH Aachen University, III. Physikalisches Institut B, Aachen, GermanyM. Bontenackels, M. Davids, M. Duda, G. Flugge, H. Geenen, M. Giffels, W. Haj Ahmad,D. Heydhausen, T. Kress, Y. Kuessel, A. Linn, A. Nowack, L. Perchalla, O. Pooth, J. Rennefeld,P. Sauerland, A. Stahl, M. Thomas, D. Tornier, M.H. Zoeller

Deutsches Elektronen-Synchrotron, Hamburg, GermanyM. Aldaya Martin, W. Behrenhoff, U. Behrens, M. Bergholz10, K. Borras, A. Cakir, A. Campbell,E. Castro, D. Dammann, G. Eckerlin, D. Eckstein, A. Flossdorf, G. Flucke, A. Geiser, J. Hauk,H. Jung1, M. Kasemann, I. Katkov11, P. Katsas, C. Kleinwort, H. Kluge, A. Knutsson,M. Kramer, D. Krucker, E. Kuznetsova, W. Lange, W. Lohmann10, R. Mankel, M. Marienfeld,I.-A. Melzer-Pellmann, A.B. Meyer, J. Mnich, A. Mussgiller, J. Olzem, D. Pitzl, A. Raspereza,A. Raval, M. Rosin, R. Schmidt10, T. Schoerner-Sadenius, N. Sen, A. Spiridonov, M. Stein,J. Tomaszewska, R. Walsh, C. Wissing

University of Hamburg, Hamburg, GermanyC. Autermann, V. Blobel, S. Bobrovskyi, J. Draeger, H. Enderle, U. Gebbert, K. Kaschube,G. Kaussen, R. Klanner, J. Lange, B. Mura, S. Naumann-Emme, F. Nowak, N. Pietsch, C. Sander,

12 1 The CMS Collaboration

H. Schettler, P. Schleper, M. Schroder, T. Schum, J. Schwandt, H. Stadie, G. Steinbruck,J. Thomsen

Institut fur Experimentelle Kernphysik, Karlsruhe, GermanyC. Barth, J. Bauer, V. Buege, T. Chwalek, W. De Boer, A. Dierlamm, G. Dirkes, M. Feindt,J. Gruschke, C. Hackstein, F. Hartmann, M. Heinrich, H. Held, K.H. Hoffmann, S. Honc,J.R. Komaragiri, T. Kuhr, D. Martschei, S. Mueller, Th. Muller, M. Niegel, O. Oberst, A. Oehler,J. Ott, T. Peiffer, D. Piparo, G. Quast, K. Rabbertz, F. Ratnikov, N. Ratnikova, M. Renz, C. Saout,A. Scheurer, P. Schieferdecker, F.-P. Schilling, M. Schmanau, G. Schott, H.J. Simonis, F.M. Stober,D. Troendle, J. Wagner-Kuhr, T. Weiler, M. Zeise, V. Zhukov11, E.B. Ziebarth

Institute of Nuclear Physics ”Demokritos”, Aghia Paraskevi, GreeceG. Daskalakis, T. Geralis, K. Karafasoulis, S. Kesisoglou, A. Kyriakis, D. Loukas, I. Manolakos,A. Markou, C. Markou, C. Mavrommatis, E. Ntomari, E. Petrakou

University of Athens, Athens, GreeceL. Gouskos, T.J. Mertzimekis, A. Panagiotou, E. Stiliaris

University of Ioannina, Ioannina, GreeceI. Evangelou, C. Foudas, P. Kokkas, N. Manthos, I. Papadopoulos, V. Patras, F.A. Triantis

KFKI Research Institute for Particle and Nuclear Physics, Budapest, HungaryA. Aranyi, G. Bencze, L. Boldizsar, C. Hajdu1, P. Hidas, D. Horvath12, A. Kapusi, K. Krajczar13,F. Sikler1, G.I. Veres13, G. Vesztergombi13

Institute of Nuclear Research ATOMKI, Debrecen, HungaryN. Beni, J. Molnar, J. Palinkas, Z. Szillasi, V. Veszpremi

University of Debrecen, Debrecen, HungaryP. Raics, Z.L. Trocsanyi, B. Ujvari

Panjab University, Chandigarh, IndiaS. Bansal, S.B. Beri, V. Bhatnagar, N. Dhingra, R. Gupta, M. Jindal, M. Kaur, J.M. Kohli,M.Z. Mehta, N. Nishu, L.K. Saini, A. Sharma, A.P. Singh, J.B. Singh, S.P. Singh

University of Delhi, Delhi, IndiaS. Ahuja, S. Bhattacharya, B.C. Choudhary, P. Gupta, S. Jain, S. Jain, A. Kumar, K. Ranjan,R.K. Shivpuri

Bhabha Atomic Research Centre, Mumbai, IndiaR.K. Choudhury, D. Dutta, S. Kailas, V. Kumar, A.K. Mohanty1, L.M. Pant, P. Shukla

Tata Institute of Fundamental Research - EHEP, Mumbai, IndiaT. Aziz, M. Guchait14, A. Gurtu, M. Maity15, D. Majumder, G. Majumder, K. Mazumdar,G.B. Mohanty, A. Saha, K. Sudhakar, N. Wickramage

Tata Institute of Fundamental Research - HECR, Mumbai, IndiaS. Banerjee, S. Dugad, N.K. Mondal

Institute for Research and Fundamental Sciences (IPM), Tehran, IranH. Arfaei, H. Bakhshiansohi16, S.M. Etesami, A. Fahim16, M. Hashemi, A. Jafari16, M. Khakzad,A. Mohammadi17, M. Mohammadi Najafabadi, S. Paktinat Mehdiabadi, B. Safarzadeh,M. Zeinali18

INFN Sezione di Bari a, Universita di Bari b, Politecnico di Bari c, Bari, ItalyM. Abbresciaa,b, L. Barbonea,b, C. Calabriaa ,b, A. Colaleoa, D. Creanzaa,c, N. De Filippisa,c,1,

13

M. De Palmaa ,b, L. Fiorea, G. Iasellia,c, L. Lusitoa ,b, G. Maggia,c, M. Maggia, N. Mannaa ,b,B. Marangellia ,b, S. Mya ,c, S. Nuzzoa,b, N. Pacificoa,b, G.A. Pierroa, A. Pompilia ,b, G. Pugliesea,c,F. Romanoa ,c, G. Rosellia ,b, G. Selvaggia,b, L. Silvestrisa, R. Trentaduea, S. Tupputia ,b, G. Zitoa

INFN Sezione di Bologna a, Universita di Bologna b, Bologna, ItalyG. Abbiendia, A.C. Benvenutia, D. Bonacorsia, S. Braibant-Giacomellia,b, L. Brigliadoria,P. Capiluppia,b, A. Castroa,b, F.R. Cavalloa, M. Cuffiania ,b, G.M. Dallavallea, F. Fabbria,A. Fanfania ,b, D. Fasanellaa, P. Giacomellia, M. Giuntaa, S. Marcellinia, G. Masetti,M. Meneghellia ,b, A. Montanaria, F.L. Navarriaa,b, F. Odoricia, A. Perrottaa, F. Primaveraa,A.M. Rossia,b, T. Rovellia ,b, G. Sirolia,b, R. Travaglinia,b

INFN Sezione di Catania a, Universita di Catania b, Catania, ItalyS. Albergoa,b, G. Cappelloa ,b, M. Chiorbolia ,b ,1, S. Costaa,b, A. Tricomia,b, C. Tuvea

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. Frosalia ,b, E. Galloa,S. Gonzia,b, P. Lenzia ,b, M. Meschinia, S. Paolettia, G. Sguazzonia, A. Tropianoa,1

INFN Laboratori Nazionali di Frascati, Frascati, ItalyL. Benussi, S. Bianco, S. Colafranceschi19, F. Fabbri, D. Piccolo

INFN Sezione di Genova, Genova, ItalyP. Fabbricatore, R. Musenich

INFN Sezione di Milano-Bicocca a, Universita di Milano-Bicocca b, Milano, ItalyA. Benagliaa,b, F. De Guioa ,b ,1, L. Di Matteoa,b, A. Ghezzia ,b, M. Malbertia,b, S. Malvezzia,A. Martellia ,b, A. Massironia,b, D. Menascea, L. Moronia, M. Paganonia,b, D. Pedrinia,S. Ragazzia,b, N. Redaellia, S. Salaa, T. Tabarelli de Fatisa,b, V. Tancinia ,b

INFN Sezione di Napoli a, Universita di Napoli ”Federico II” b, Napoli, ItalyS. Buontempoa, C.A. Carrillo Montoyaa,1, N. Cavalloa ,20, A. De Cosaa ,b, F. Fabozzia ,20,A.O.M. Iorioa ,1, L. Listaa, M. Merolaa ,b, P. Paoluccia

INFN Sezione di Padova a, Universita di Padova b, Universita di Trento (Trento) c, Padova,ItalyP. Azzia, N. Bacchettaa, P. Bellana ,b, D. Biselloa ,b, A. Brancaa, R. Carlina ,b, P. Checchiaa,M. De Mattiaa,b, T. Dorigoa, U. Dossellia, F. Fanzagoa, F. Gasparinia ,b, U. Gasparinia ,b,S. Lacapraraa,21, I. Lazzizzeraa,c, M. Margonia,b, M. Mazzucatoa, A.T. Meneguzzoa ,b,M. Nespoloa,1, L. Perrozzia ,1, N. Pozzobona,b, P. Ronchesea ,b, F. Simonettoa,b, E. Torassaa,M. Tosia ,b, S. Vaninia,b, P. Zottoa ,b, G. Zumerlea,b

INFN Sezione di Pavia a, Universita di Pavia b, Pavia, ItalyP. Baessoa,b, U. Berzanoa, S.P. Rattia,b, C. Riccardia,b, P. Torrea ,b, P. Vituloa,b, C. Viviania ,b

INFN Sezione di Perugia a, Universita di Perugia b, Perugia, ItalyM. Biasinia ,b, G.M. Bileia, B. Caponeria,b, L. Fanoa,b, P. Laricciaa ,b, A. Lucaronia ,b ,1,G. Mantovania ,b, M. Menichellia, A. Nappia,b, F. Romeoa ,b, A. Santocchiaa ,b, S. Taronia ,b ,1,M. Valdataa,b

INFN Sezione di Pisa a, Universita di Pisa b, Scuola Normale Superiore di Pisa c, Pisa, ItalyP. Azzurria ,c, G. Bagliesia, J. Bernardinia,b, T. Boccalia ,1, G. Broccoloa ,c, R. Castaldia,R.T. D’Agnoloa ,c, R. Dell’Orsoa, F. Fioria ,b, L. Foaa,c, A. Giassia, A. Kraana, F. Ligabuea ,c,T. Lomtadzea, L. Martinia ,22, A. Messineoa,b, F. Pallaa, G. Segneria, A.T. Serbana, P. Spagnoloa,R. Tenchinia, G. Tonellia,b,1, A. Venturia ,1, P.G. Verdinia

14 1 The CMS Collaboration

INFN Sezione di Roma a, Universita di Roma ”La Sapienza” b, Roma, ItalyL. Baronea ,b, F. Cavallaria, D. Del Rea,b, E. Di Marcoa,b, M. Diemoza, D. Francia ,b, M. Grassia,1,E. Longoa,b, S. Nourbakhsha, G. Organtinia,b, F. Pandolfia ,b ,1, R. Paramattia, S. Rahatloua,b

INFN Sezione di Torino a, Universita di Torino b, Universita del Piemonte Orientale (No-vara) c, Torino, ItalyN. Amapanea,b, R. Arcidiaconoa,c, S. Argiroa ,b, M. Arneodoa ,c, C. Biinoa, C. Bottaa,b ,1,N. Cartigliaa, R. Castelloa ,b, M. Costaa ,b, N. Demariaa, A. Grazianoa ,b ,1, C. Mariottia,M. Maronea,b, S. Masellia, E. Migliorea,b, G. Milaa,b, V. Monacoa,b, M. Musicha ,b,M.M. Obertinoa,c, N. Pastronea, M. Pelliccionia,b, A. Romeroa,b, M. Ruspaa,c, R. Sacchia ,b,V. Solaa ,b, A. Solanoa ,b, A. Staianoa, A. Vilela Pereiraa

INFN Sezione di Trieste a, Universita di Trieste b, Trieste, ItalyS. Belfortea, F. Cossuttia, G. Della Riccaa,b, B. Gobboa, D. Montaninoa,b, A. Penzoa

Kangwon National University, Chunchon, KoreaS.G. Heo, S.K. Nam

Kyungpook National University, Daegu, KoreaS. Chang, J. Chung, D.H. Kim, G.N. Kim, J.E. Kim, D.J. Kong, H. Park, S.R. Ro, D. Son, D.C. Son,T. Son

Chonnam National University, Institute for Universe and Elementary Particles, Kwangju,KoreaZero Kim, J.Y. Kim, S. Song

Korea University, Seoul, KoreaS. Choi, B. Hong, M.S. Jeong, M. Jo, H. Kim, J.H. Kim, T.J. Kim, K.S. Lee, D.H. Moon, S.K. Park,H.B. Rhee, E. Seo, S. Shin, K.S. Sim

University of Seoul, Seoul, KoreaM. Choi, S. Kang, H. Kim, C. Park, I.C. Park, S. Park, G. Ryu

Sungkyunkwan University, Suwon, KoreaY. Choi, Y.K. Choi, J. Goh, M.S. Kim, E. Kwon, J. Lee, S. Lee, H. Seo, I. Yu

Vilnius University, Vilnius, LithuaniaM.J. Bilinskas, I. Grigelionis, M. Janulis, D. Martisiute, P. Petrov, T. Sabonis

Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, MexicoH. Castilla-Valdez, E. De La Cruz-Burelo, R. Lopez-Fernandez, R. Magana Villalba, A. Sanchez-Hernandez, L.M. Villasenor-Cendejas

Universidad Iberoamericana, Mexico City, MexicoS. Carrillo Moreno, F. Vazquez Valencia

Benemerita Universidad Autonoma de Puebla, Puebla, MexicoH.A. Salazar Ibarguen

Universidad Autonoma de San Luis Potosı, San Luis Potosı, MexicoE. Casimiro Linares, A. Morelos Pineda, M.A. Reyes-Santos

University of Auckland, Auckland, New ZealandD. Krofcheck, J. Tam

University of Canterbury, Christchurch, New ZealandP.H. Butler, R. Doesburg, H. Silverwood

15

National Centre for Physics, Quaid-I-Azam University, Islamabad, PakistanM. Ahmad, I. Ahmed, M.I. Asghar, H.R. Hoorani, W.A. Khan, T. Khurshid, S. Qazi

Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, PolandM. Cwiok, W. Dominik, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski

Soltan Institute for Nuclear Studies, Warsaw, PolandT. Frueboes, R. Gokieli, M. Gorski, M. Kazana, K. Nawrocki, K. Romanowska-Rybinska,M. Szleper, G. Wrochna, P. Zalewski

Laboratorio de Instrumentacao e Fısica Experimental de Partıculas, Lisboa, PortugalN. Almeida, P. Bargassa, A. David, P. Faccioli, P.G. Ferreira Parracho, M. Gallinaro, P. Musella,A. Nayak, P.Q. Ribeiro, J. Seixas, J. Varela

Joint Institute for Nuclear Research, Dubna, RussiaS. Afanasiev, I. Belotelov, P. Bunin, I. Golutvin, A. Kamenev, V. Karjavin, G. Kozlov, A. Lanev,P. Moisenz, V. Palichik, V. Perelygin, S. Shmatov, V. Smirnov, A. Volodko, A. Zarubin

Petersburg Nuclear Physics Institute, Gatchina (St Petersburg), RussiaV. Golovtsov, Y. Ivanov, V. Kim, P. Levchenko, V. Murzin, V. Oreshkin, I. Smirnov, V. Sulimov,L. Uvarov, S. Vavilov, A. Vorobyev, A. Vorobyev

Institute for Nuclear Research, Moscow, RussiaYu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, M. Kirsanov, N. Krasnikov, V. Matveev,A. Pashenkov, A. Toropin, S. Troitsky

Institute for Theoretical and Experimental Physics, Moscow, RussiaV. Epshteyn, V. Gavrilov, V. Kaftanov†, M. Kossov1, A. Krokhotin, N. Lychkovskaya, V. Popov,G. Safronov, S. Semenov, V. Stolin, E. Vlasov, A. Zhokin

Moscow State University, Moscow, RussiaE. Boos, M. Dubinin23, L. Dudko, A. Ershov, A. Gribushin, O. Kodolova, I. Lokhtin, A. Markina,S. Obraztsov, M. Perfilov, S. Petrushanko, L. Sarycheva, V. Savrin, A. Snigirev

P.N. Lebedev Physical Institute, Moscow, RussiaV. Andreev, M. Azarkin, I. Dremin, M. Kirakosyan, A. Leonidov, S.V. Rusakov, A. Vinogradov

State Research Center of Russian Federation, Institute for High Energy Physics, Protvino,RussiaI. Azhgirey, S. Bitioukov, V. Grishin1, V. Kachanov, D. Konstantinov, A. Korablev, V. Krychkine,V. Petrov, R. Ryutin, S. Slabospitsky, 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. Adzic24, M. Djordjevic, D. Krpic24, J. Milosevic

Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT),Madrid, SpainM. Aguilar-Benitez, J. Alcaraz Maestre, P. Arce, C. Battilana, E. Calvo, M. Cepeda, M. Cerrada,M. Chamizo Llatas, N. Colino, B. De La Cruz, A. Delgado Peris, C. Diez Pardos, D. DomınguezVazquez, C. Fernandez Bedoya, J.P. Fernandez Ramos, A. Ferrando, J. Flix, M.C. Fouz,P. Garcia-Abia, O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, G. Merino,J. Puerta Pelayo, I. Redondo, L. Romero, J. Santaolalla, M.S. Soares, C. Willmott

16 1 The CMS Collaboration

Universidad Autonoma de Madrid, Madrid, SpainC. Albajar, G. Codispoti, J.F. de Troconiz

Universidad de Oviedo, Oviedo, SpainJ. Cuevas, J. Fernandez Menendez, S. Folgueras, I. Gonzalez Caballero, L. Lloret Iglesias,J.M. Vizan Garcia

Instituto de Fısica de Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, SpainJ.A. Brochero Cifuentes, I.J. Cabrillo, A. Calderon, S.H. Chuang, J. Duarte Campderros,M. Felcini25, M. Fernandez, G. Gomez, J. Gonzalez Sanchez, C. Jorda, P. Lobelle Pardo, A. LopezVirto, J. Marco, R. Marco, C. Martinez Rivero, F. Matorras, F.J. Munoz Sanchez, J. PiedraGomez26, T. Rodrigo, A.Y. Rodrıguez-Marrero, A. Ruiz-Jimeno, L. Scodellaro, M. SobronSanudo, I. Vila, R. Vilar Cortabitarte

CERN, European Organization for Nuclear Research, Geneva, SwitzerlandD. Abbaneo, E. Auffray, G. Auzinger, P. Baillon, A.H. Ball, D. Barney, A.J. Bell27, D. Benedetti,C. Bernet3, W. Bialas, P. Bloch, A. Bocci, S. Bolognesi, M. Bona, H. Breuker, G. Brona,K. Bunkowski, T. Camporesi, G. Cerminara, J.A. Coarasa Perez, B. Cure, D. D’Enterria,A. De Roeck, S. Di Guida, A. Elliott-Peisert, B. Frisch, W. Funk, A. Gaddi, S. Gennai,G. Georgiou, H. Gerwig, D. Gigi, K. Gill, D. Giordano, F. Glege, R. Gomez-Reino Garrido,M. Gouzevitch, P. Govoni, S. Gowdy, L. Guiducci, M. Hansen, C. Hartl, J. Harvey, J. Hegeman,B. Hegner, H.F. Hoffmann, A. Honma, V. Innocente, P. Janot, K. Kaadze, E. Karavakis, P. Lecoq,C. Lourenco, T. Maki, L. Malgeri, M. Mannelli, L. Masetti, A. Maurisset, F. Meijers, S. Mersi,E. Meschi, R. Moser, M.U. Mozer, M. Mulders, E. Nesvold1, M. Nguyen, T. Orimoto, L. Orsini,E. Perez, A. Petrilli, A. Pfeiffer, M. Pierini, M. Pimia, G. Polese, A. Racz, J. Rodrigues Antunes,G. Rolandi28, T. Rommerskirchen, C. Rovelli29, M. Rovere, H. Sakulin, C. Schafer, C. Schwick,I. Segoni, A. Sharma, P. Siegrist, M. Simon, P. Sphicas30, M. Spiropulu23, M. Stoye, P. Tropea,A. Tsirou, P. Vichoudis, M. Voutilainen, W.D. Zeuner

Paul Scherrer Institut, Villigen, SwitzerlandW. Bertl, K. Deiters, W. Erdmann, K. Gabathuler, R. Horisberger, Q. Ingram, H.C. Kaestli,S. Konig, D. Kotlinski, U. Langenegger, F. Meier, D. Renker, T. Rohe, J. Sibille31,A. Starodumov32

Institute for Particle Physics, ETH Zurich, Zurich, SwitzerlandP. Bortignon, L. Caminada33, N. Chanon, Z. Chen, S. Cittolin, G. Dissertori, M. Dittmar,J. Eugster, K. Freudenreich, C. Grab, A. Herve, W. Hintz, P. Lecomte, W. Lustermann,C. Marchica33, P. Martinez Ruiz del Arbol, P. Meridiani, P. Milenovic34, F. Moortgat, C. Nageli33,P. Nef, F. Nessi-Tedaldi, L. Pape, F. Pauss, T. Punz, A. Rizzi, F.J. Ronga, M. Rossini, L. Sala,A.K. Sanchez, M.-C. Sawley, B. Stieger, L. Tauscher†, A. Thea, K. Theofilatos, D. Treille,C. Urscheler, R. Wallny, M. Weber, L. Wehrli, J. Weng

Universitat Zurich, Zurich, SwitzerlandE. Aguilo, C. Amsler, V. Chiochia, S. De Visscher, C. Favaro, M. Ivova Rikova, B. Millan Mejias,P. Otiougova, C. Regenfus, P. Robmann, A. Schmidt, H. Snoek

National Central University, Chung-Li, TaiwanY.H. Chang, K.H. Chen, S. Dutta, C.M. Kuo, S.W. Li, W. Lin, Z.K. Liu, Y.J. Lu, D. Mekterovic,R. Volpe, J.H. Wu, S.S. Yu

National Taiwan University (NTU), Taipei, TaiwanP. Bartalini, P. Chang, Y.H. Chang, Y.W. Chang, Y. Chao, K.F. Chen, W.-S. Hou, Y. Hsiung,K.Y. Kao, Y.J. Lei, R.-S. Lu, J.G. Shiu, Y.M. Tzeng, M. Wang

17

Cukurova University, Adana, TurkeyA. Adiguzel, M.N. Bakirci35, S. Cerci36, C. Dozen, I. Dumanoglu, E. Eskut, S. Girgis,G. Gokbulut, Y. Guler, E. Gurpinar, I. Hos, E.E. Kangal, T. Karaman, A. Kayis Topaksu,A. Nart, G. Onengut, K. Ozdemir, S. Ozturk, A. Polatoz, K. Sogut37, D. Sunar Cerci36, B. Tali,H. Topakli35, D. Uzun, L.N. Vergili, M. Vergili, C. Zorbilmez

Middle East Technical University, Physics Department, Ankara, TurkeyI.V. Akin, T. Aliev, S. Bilmis, M. Deniz, H. Gamsizkan, A.M. Guler, K. Ocalan, A. Ozpineci,M. Serin, R. Sever, U.E. Surat, E. Yildirim, M. Zeyrek

Bogazici University, Istanbul, TurkeyM. Deliomeroglu, D. Demir38, E. Gulmez, B. Isildak, M. Kaya39, O. Kaya39, S. Ozkorucuklu40,N. Sonmez41

National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, UkraineL. Levchuk

University of Bristol, Bristol, United KingdomF. Bostock, J.J. Brooke, T.L. Cheng, E. Clement, D. Cussans, R. Frazier, J. Goldstein,M. Grimes, M. Hansen, D. Hartley, G.P. Heath, H.F. Heath, J. Jackson, L. Kreczko, S. Metson,D.M. Newbold42, K. Nirunpong, A. Poll, S. Senkin, V.J. Smith, S. Ward

Rutherford Appleton Laboratory, Didcot, United KingdomL. Basso43, K.W. Bell, A. Belyaev43, C. Brew, R.M. Brown, B. Camanzi, D.J.A. Cockerill,J.A. Coughlan, K. Harder, S. Harper, B.W. Kennedy, E. Olaiya, D. Petyt, B.C. Radburn-Smith,C.H. Shepherd-Themistocleous, I.R. Tomalin, W.J. Womersley, S.D. Worm

Imperial College, London, United KingdomR. Bainbridge, G. Ball, J. Ballin, R. Beuselinck, O. Buchmuller, D. Colling, N. Cripps, M. Cutajar,G. Davies, M. Della Negra, W. Ferguson, J. Fulcher, D. Futyan, A. Gilbert, A. Guneratne Bryer,G. Hall, Z. Hatherell, J. Hays, G. Iles, M. Jarvis, G. Karapostoli, L. Lyons, B.C. MacEvoy, A.-M. Magnan, J. Marrouche, B. Mathias, R. Nandi, J. Nash, A. Nikitenko32, A. Papageorgiou,M. Pesaresi, K. Petridis, M. Pioppi44, D.M. Raymond, S. Rogerson, N. Rompotis, A. Rose,M.J. Ryan, C. Seez, P. Sharp, A. Sparrow, A. Tapper, S. Tourneur, M. Vazquez Acosta, T. Virdee,S. Wakefield, N. Wardle, D. Wardrope, T. Whyntie

Brunel University, Uxbridge, United KingdomM. Barrett, M. Chadwick, J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, D. Leslie, W. Martin,I.D. Reid, L. Teodorescu

Baylor University, Waco, USAK. Hatakeyama

Boston University, Boston, USAT. Bose, E. Carrera Jarrin, C. Fantasia, A. Heister, J. St. John, P. Lawson, D. Lazic, J. Rohlf,D. Sperka, L. Sulak

Brown University, Providence, USAA. Avetisyan, S. Bhattacharya, J.P. Chou, D. Cutts, A. Ferapontov, U. Heintz, S. Jabeen,G. Kukartsev, G. Landsberg, M. Narain, D. Nguyen, M. Segala, T. Sinthuprasith, T. Speer,K.V. Tsang

University of California, Davis, Davis, USAR. Breedon, M. Calderon De La Barca Sanchez, S. Chauhan, M. Chertok, J. Conway, P.T. Cox,J. Dolen, R. Erbacher, E. Friis, W. Ko, A. Kopecky, R. Lander, H. Liu, S. Maruyama, T. Miceli,

18 1 The CMS Collaboration

M. Nikolic, D. Pellett, J. Robles, S. Salur, T. Schwarz, M. Searle, J. Smith, M. Squires, M. Tripathi,R. Vasquez Sierra, C. Veelken

University of California, Los Angeles, Los Angeles, USAV. Andreev, K. Arisaka, D. Cline, R. Cousins, A. Deisher, J. Duris, S. Erhan, C. Farrell, J. Hauser,M. Ignatenko, C. Jarvis, C. Plager, G. Rakness, P. Schlein†, J. Tucker, V. Valuev

University of California, Riverside, Riverside, USAJ. Babb, A. Chandra, R. Clare, J. Ellison, J.W. Gary, F. Giordano, G. Hanson, G.Y. Jeng,S.C. Kao, F. Liu, H. Liu, O.R. Long, A. Luthra, H. Nguyen, B.C. Shen†, R. Stringer, J. Sturdy,S. Sumowidagdo, R. Wilken, S. Wimpenny

University of California, San Diego, La Jolla, USAW. Andrews, J.G. Branson, G.B. Cerati, E. Dusinberre, D. Evans, F. Golf, A. Holzner, R. Kelley,M. Lebourgeois, J. Letts, B. Mangano, S. Padhi, C. Palmer, G. Petrucciani, H. Pi, M. Pieri,R. Ranieri, M. Sani, V. Sharma, S. Simon, Y. Tu, A. Vartak, S. Wasserbaech45, F. Wurthwein,A. Yagil, J. Yoo

University of California, Santa Barbara, Santa Barbara, USAD. Barge, R. Bellan, C. Campagnari, M. D’Alfonso, T. Danielson, K. Flowers, P. Geffert,J. Incandela, C. Justus, P. Kalavase, S.A. Koay, D. Kovalskyi, V. Krutelyov, S. Lowette, N. Mccoll,V. Pavlunin, F. Rebassoo, J. Ribnik, J. Richman, R. Rossin, D. Stuart, W. To, J.R. Vlimant

California Institute of Technology, Pasadena, USAA. Apresyan, A. Bornheim, J. Bunn, Y. Chen, M. Gataullin, Y. Ma, A. Mott, H.B. Newman,C. Rogan, K. Shin, V. Timciuc, P. Traczyk, J. Veverka, R. Wilkinson, Y. Yang, R.Y. Zhu

Carnegie Mellon University, Pittsburgh, USAB. Akgun, R. Carroll, T. Ferguson, Y. Iiyama, D.W. Jang, S.Y. Jun, Y.F. Liu, M. Paulini, J. Russ,H. Vogel, I. Vorobiev

University of Colorado at Boulder, Boulder, USAJ.P. Cumalat, M.E. Dinardo, B.R. Drell, C.J. Edelmaier, W.T. Ford, A. Gaz, B. Heyburn, E. LuiggiLopez, U. Nauenberg, J.G. Smith, K. Stenson, K.A. Ulmer, S.R. Wagner, S.L. Zang

Cornell University, Ithaca, USAL. Agostino, J. Alexander, D. Cassel, A. Chatterjee, S. Das, N. Eggert, L.K. Gibbons, B. Heltsley,W. Hopkins, A. Khukhunaishvili, B. Kreis, G. Nicolas Kaufman, J.R. Patterson, D. Puigh,A. Ryd, E. Salvati, X. Shi, W. Sun, W.D. Teo, J. Thom, J. Thompson, J. Vaughan, Y. Weng,L. Winstrom, P. Wittich

Fairfield University, Fairfield, USAA. Biselli, G. Cirino, D. Winn

Fermi National Accelerator Laboratory, Batavia, USAS. Abdullin, M. Albrow, J. Anderson, G. Apollinari, M. Atac, J.A. Bakken, S. Banerjee,L.A.T. Bauerdick, A. Beretvas, J. Berryhill, P.C. Bhat, I. Bloch, F. Borcherding, K. Burkett,J.N. Butler, V. Chetluru, H.W.K. Cheung, F. Chlebana, S. Cihangir, W. Cooper, D.P. Eartly,V.D. Elvira, S. Esen, I. Fisk, J. Freeman, Y. Gao, E. Gottschalk, D. Green, K. Gunthoti,O. Gutsche, J. Hanlon, R.M. Harris, J. Hirschauer, B. Hooberman, H. Jensen, M. Johnson,U. Joshi, R. Khatiwada, B. Klima, K. Kousouris, S. Kunori, S. Kwan, C. Leonidopoulos,P. Limon, D. Lincoln, R. Lipton, J. Lykken, K. Maeshima, J.M. Marraffino, D. Mason, P. McBride,T. Miao, K. Mishra, S. Mrenna, Y. Musienko46, C. Newman-Holmes, V. O’Dell, R. Pordes,O. Prokofyev, N. Saoulidou, E. Sexton-Kennedy, S. Sharma, A. Soha, W.J. Spalding, L. Spiegel,

19

P. Tan, L. Taylor, S. Tkaczyk, L. Uplegger, E.W. Vaandering, R. Vidal, J. Whitmore, W. Wu,F. Yang, F. Yumiceva, J.C. Yun

University of Florida, Gainesville, USAD. Acosta, P. Avery, D. Bourilkov, M. Chen, M. De Gruttola, G.P. Di Giovanni, D. Dobur,A. Drozdetskiy, R.D. Field, M. Fisher, Y. Fu, I.K. Furic, J. Gartner, B. Kim, J. Konigsberg,A. Korytov, A. Kropivnitskaya, T. Kypreos, K. Matchev, G. Mitselmakher, L. Muniz,Y. Pakhotin, C. Prescott, R. Remington, M. Schmitt, B. Scurlock, P. Sellers, N. Skhirtladze,M. Snowball, D. Wang, J. Yelton, M. Zakaria

Florida International University, Miami, USAC. Ceron, V. Gaultney, L. Kramer, L.M. Lebolo, S. Linn, P. Markowitz, G. Martinez, D. Mesa,J.L. Rodriguez

Florida State University, Tallahassee, USAT. Adams, A. Askew, D. Bandurin, J. Bochenek, J. Chen, B. Diamond, S.V. Gleyzer, J. Haas,S. Hagopian, V. Hagopian, M. Jenkins, K.F. Johnson, H. Prosper, L. Quertenmont, S. Sekmen,V. Veeraraghavan

Florida Institute of Technology, Melbourne, USAM.M. Baarmand, B. Dorney, S. Guragain, M. Hohlmann, H. Kalakhety, R. Ralich,I. Vodopiyanov

University of Illinois at Chicago (UIC), Chicago, USAM.R. Adams, I.M. Anghel, L. Apanasevich, Y. Bai, V.E. Bazterra, R.R. Betts, J. Callner,R. Cavanaugh, C. Dragoiu, L. Gauthier, C.E. Gerber, D.J. Hofman, S. Khalatyan, G.J. Kunde47,F. Lacroix, M. Malek, C. O’Brien, C. Silvestre, A. Smoron, D. Strom, N. Varelas

The University of Iowa, Iowa City, USAU. Akgun, E.A. Albayrak, B. Bilki, W. Clarida, F. Duru, C.K. Lae, E. McCliment, J.-P. Merlo,H. Mermerkaya48, A. Mestvirishvili, A. Moeller, J. Nachtman, C.R. Newsom, E. Norbeck,J. Olson, Y. Onel, F. Ozok, S. Sen, J. Wetzel, T. Yetkin, K. Yi

Johns Hopkins University, Baltimore, USAB.A. Barnett, B. Blumenfeld, A. Bonato, C. Eskew, D. Fehling, G. Giurgiu, A.V. Gritsan, Z.J. Guo,G. Hu, P. Maksimovic, S. Rappoccio, M. Swartz, N.V. Tran, A. Whitbeck

The University of Kansas, Lawrence, USAP. Baringer, A. Bean, G. Benelli, O. Grachov, R.P. Kenny Iii, M. Murray, D. Noonan, S. Sanders,J.S. Wood, V. Zhukova

Kansas State University, Manhattan, USAA.f. Barfuss, T. Bolton, I. Chakaberia, A. Ivanov, S. Khalil, M. Makouski, Y. Maravin, S. Shrestha,I. Svintradze, Z. Wan

Lawrence Livermore National Laboratory, Livermore, USAJ. Gronberg, D. Lange, D. Wright

University of Maryland, College Park, USAA. Baden, M. Boutemeur, S.C. Eno, D. Ferencek, J.A. Gomez, N.J. Hadley, R.G. Kellogg, M. Kirn,Y. Lu, A.C. Mignerey, K. Rossato, P. Rumerio, F. Santanastasio, A. Skuja, J. Temple, M.B. Tonjes,S.C. Tonwar, E. Twedt

Massachusetts Institute of Technology, Cambridge, USAB. Alver, G. Bauer, J. Bendavid, W. Busza, E. Butz, I.A. Cali, M. Chan, V. Dutta, P. Everaerts,

20 1 The CMS Collaboration

G. Gomez Ceballos, M. Goncharov, K.A. Hahn, P. Harris, Y. Kim, M. Klute, Y.-J. Lee, W. Li,C. Loizides, P.D. Luckey, T. Ma, S. Nahn, C. Paus, D. Ralph, C. Roland, G. Roland, M. Rudolph,G.S.F. Stephans, F. Stockli, K. Sumorok, K. Sung, E.A. Wenger, S. Xie, M. Yang, Y. Yilmaz,A.S. Yoon, M. Zanetti

University of Minnesota, Minneapolis, USAP. Cole, S.I. Cooper, P. Cushman, B. Dahmes, A. De Benedetti, P.R. Dudero, G. Franzoni,J. Haupt, K. Klapoetke, Y. Kubota, J. Mans, V. Rekovic, R. Rusack, M. Sasseville, A. Singovsky

University of Mississippi, University, USAL.M. Cremaldi, R. Godang, R. Kroeger, L. Perera, R. Rahmat, D.A. Sanders, D. Summers

University of Nebraska-Lincoln, Lincoln, USAK. Bloom, S. Bose, J. Butt, D.R. Claes, A. Dominguez, M. Eads, J. Keller, T. Kelly, I. Kravchenko,J. Lazo-Flores, H. Malbouisson, S. Malik, G.R. Snow

State University of New York at Buffalo, Buffalo, USAU. Baur, A. Godshalk, I. Iashvili, S. Jain, A. Kharchilava, A. Kumar, S.P. Shipkowski, K. Smith

Northeastern University, Boston, USAG. Alverson, E. Barberis, D. Baumgartel, O. Boeriu, M. Chasco, S. Reucroft, J. Swain, D. Trocino,D. Wood, J. Zhang

Northwestern University, Evanston, USAA. Anastassov, A. Kubik, N. Odell, R.A. Ofierzynski, B. Pollack, A. Pozdnyakov, M. Schmitt,S. Stoynev, M. Velasco, S. Won

University of Notre Dame, Notre Dame, USAL. Antonelli, D. Berry, M. Hildreth, C. Jessop, D.J. Karmgard, J. Kolb, T. Kolberg, K. Lannon,W. Luo, S. Lynch, N. Marinelli, D.M. Morse, T. Pearson, R. Ruchti, J. Slaunwhite, N. Valls,M. Wayne, J. Ziegler

The Ohio State University, Columbus, USAB. Bylsma, L.S. Durkin, J. Gu, C. Hill, P. Killewald, K. Kotov, T.Y. Ling, M. Rodenburg,G. Williams

Princeton University, Princeton, USAN. Adam, E. Berry, P. Elmer, D. Gerbaudo, V. Halyo, P. Hebda, A. Hunt, J. Jones, E. Laird,D. Lopes Pegna, D. Marlow, T. Medvedeva, M. Mooney, J. Olsen, P. Piroue, X. Quan, H. Saka,D. Stickland, C. Tully, J.S. Werner, A. Zuranski

University of Puerto Rico, Mayaguez, USAJ.G. Acosta, X.T. Huang, A. Lopez, H. Mendez, S. Oliveros, J.E. Ramirez Vargas,A. Zatserklyaniy

Purdue University, West Lafayette, USAE. Alagoz, V.E. Barnes, G. Bolla, L. Borrello, D. Bortoletto, A. Everett, A.F. Garfinkel, L. Gutay,Z. Hu, M. Jones, O. Koybasi, M. Kress, A.T. Laasanen, N. Leonardo, C. Liu, V. Maroussov,P. Merkel, D.H. Miller, N. Neumeister, I. Shipsey, D. Silvers, A. Svyatkovskiy, H.D. Yoo,J. Zablocki, Y. Zheng

Purdue University Calumet, Hammond, USAP. Jindal, N. Parashar

21

Rice University, Houston, USAC. Boulahouache, V. Cuplov, K.M. Ecklund, F.J.M. Geurts, B.P. Padley, R. Redjimi, J. Roberts,J. Zabel

University of Rochester, Rochester, USAB. Betchart, A. Bodek, Y.S. Chung, R. Covarelli, P. de Barbaro, R. Demina, Y. Eshaq, H. Flacher,A. Garcia-Bellido, P. Goldenzweig, Y. Gotra, J. Han, A. Harel, D.C. Miner, D. Orbaker,G. Petrillo, D. Vishnevskiy, M. Zielinski

The Rockefeller University, New York, USAA. Bhatti, R. Ciesielski, L. Demortier, K. Goulianos, G. Lungu, S. Malik, C. Mesropian, M. Yan

Rutgers, the State University of New Jersey, Piscataway, USAO. Atramentov, A. Barker, D. Duggan, Y. Gershtein, R. Gray, E. Halkiadakis, D. Hidas, D. Hits,A. Lath, S. Panwalkar, R. Patel, A. Richards, K. Rose, S. Schnetzer, S. Somalwar, R. Stone,S. Thomas

University of Tennessee, Knoxville, USAG. Cerizza, M. Hollingsworth, S. Spanier, Z.C. Yang, A. York

Texas A&M University, College Station, USAJ. Asaadi, R. Eusebi, J. Gilmore, A. Gurrola, T. Kamon, V. Khotilovich, R. Montalvo,C.N. Nguyen, I. Osipenkov, J. Pivarski, A. Safonov, S. Sengupta, A. Tatarinov, D. Toback,M. Weinberger

Texas Tech University, Lubbock, USAN. Akchurin, C. Bardak, J. Damgov, C. Jeong, K. Kovitanggoon, S.W. Lee, Y. Roh, A. Sill,I. Volobouev, R. Wigmans, E. Yazgan

Vanderbilt University, Nashville, USAE. Appelt, E. Brownson, D. Engh, C. Florez, W. Gabella, M. Issah, W. Johns, P. Kurt, C. Maguire,A. Melo, P. Sheldon, B. Snook, S. Tuo, J. Velkovska

University of Virginia, Charlottesville, USAM.W. Arenton, M. Balazs, S. Boutle, B. Cox, B. Francis, R. Hirosky, A. Ledovskoy, C. Lin, C. Neu,R. Yohay

Wayne State University, Detroit, USAS. Gollapinni, R. Harr, P.E. Karchin, P. Lamichhane, M. Mattson, C. Milstene, A. Sakharov

University of Wisconsin, Madison, USAM. Anderson, M. Bachtis, J.N. Bellinger, D. Carlsmith, S. Dasu, J. Efron, K. Flood, L. Gray,K.S. Grogg, M. Grothe, R. Hall-Wilton, M. Herndon, P. Klabbers, J. Klukas, A. Lanaro,C. Lazaridis, J. Leonard, R. Loveless, A. Mohapatra, F. Palmonari, D. Reeder, I. Ross, A. Savin,W.H. Smith, J. Swanson, M. Weinberg

†: Deceased1: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland2: Also at Universidade Federal do ABC, Santo Andre, Brazil3: Also at Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France4: Also at Suez Canal University, Suez, Egypt5: Also at British University, Cairo, Egypt6: Also at Fayoum University, El-Fayoum, Egypt7: Also at Soltan Institute for Nuclear Studies, Warsaw, Poland8: Also at Massachusetts Institute of Technology, Cambridge, USA

22 1 The CMS Collaboration

9: Also at Universite de Haute-Alsace, Mulhouse, France10: Also at Brandenburg University of Technology, Cottbus, Germany11: Also at Moscow State University, Moscow, Russia12: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary13: Also at Eotvos Lorand University, Budapest, Hungary14: Also at Tata Institute of Fundamental Research - HECR, Mumbai, India15: Also at University of Visva-Bharati, Santiniketan, India16: Also at Sharif University of Technology, Tehran, Iran17: Also at Shiraz University, Shiraz, Iran18: Also at Isfahan University of Technology, Isfahan, Iran19: Also at Facolta Ingegneria Universita di Roma ”La Sapienza”, Roma, Italy20: Also at Universita della Basilicata, Potenza, Italy21: Also at Laboratori Nazionali di Legnaro dell’ INFN, Legnaro, Italy22: Also at Universita degli studi di Siena, Siena, Italy23: Also at California Institute of Technology, Pasadena, USA24: Also at Faculty of Physics of University of Belgrade, Belgrade, Serbia25: Also at University of California, Los Angeles, Los Angeles, USA26: Also at University of Florida, Gainesville, USA27: Also at Universite de Geneve, Geneva, Switzerland28: Also at Scuola Normale e Sezione dell’ INFN, Pisa, Italy29: Also at INFN Sezione di Roma; Universita di Roma ”La Sapienza”, Roma, Italy30: Also at University of Athens, Athens, Greece31: Also at The University of Kansas, Lawrence, USA32: Also at Institute for Theoretical and Experimental Physics, Moscow, Russia33: Also at Paul Scherrer Institut, Villigen, Switzerland34: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences,Belgrade, Serbia35: Also at Gaziosmanpasa University, Tokat, Turkey36: Also at Adiyaman University, Adiyaman, Turkey37: Also at Mersin University, Mersin, Turkey38: Also at Izmir Institute of Technology, Izmir, Turkey39: Also at Kafkas University, Kars, Turkey40: Also at Suleyman Demirel University, Isparta, Turkey41: Also at Ege University, Izmir, Turkey42: Also at Rutherford Appleton Laboratory, Didcot, United Kingdom43: Also at School of Physics and Astronomy, University of Southampton, Southampton,United Kingdom44: Also at INFN Sezione di Perugia; Universita di Perugia, Perugia, Italy45: Also at Utah Valley University, Orem, USA46: Also at Institute for Nuclear Research, Moscow, Russia47: Also at Los Alamos National Laboratory, Los Alamos, USA48: Also at Erzincan University, Erzincan, Turkey