Forward-backward asymmetry of Drell–Yan lepton pairs in pp collisions at \sqrt{s}= 7\TeV

Forward-backward asymmetry of Drell–Yan lepton pairs in pp collisions at 7\TeV


A measurement of the forward-backward asymmetry () of Drell–Yan lepton pairs in pp collisions at = 7\TeVis presented. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 5\fbinv. The asymmetry is measured as a function of dilepton mass and rapidity in the dielectron and dimuon channels. Combined results from the two channels are presented, and are compared with the standard model predictions. The measurement in the dimuon channel and the combination of the two channels are the first such results obtained at a hadron collider. The measured asymmetries are consistent with the standard model predictions.




\RCS \RCS \cmsNoteHeaderEWK-11-004

The amplitude for the standard model (SM) Drell–Yan process contains both the vector and the axial-vector couplings of electroweak bosons to fermions [1, 2]. The differential cross section can be written as {linenomath}


for a given dilepton invariant mass, at leading order, where is the emission angle of the lepton () relative to the quark momentum in the dilepton centre-of-mass frame. Forward and backward events are defined by and , respectively, and the asymmetry parameter is defined as {linenomath}


where and are the total cross sections for forward and backward events. Within the SM, the parameters and depend on the vector and axial-vector couplings of the quarks and leptons to the \cPZ boson and on the electric charge of the fermions.

The Drell–Yan cross section is modified by higher-order quantum chromodynamic (QCD) and radiative electroweak corrections. The electroweak corrections are negligible except near the \cPZ peak. At dilepton masses near the \cPZ peak, is predicted to be small because of the small value of the lepton vector coupling in the SM, and is sensitive to the electroweak mixing parameter . Our measurement of with a maximum-likelihood fit technique based on a smaller data set was reported in Ref. [3]. Above and below the \cPZ peak, exhibits a characteristic energy dependence governed by virtual photon and \cPZ interference. Deviations from the SM prediction for may indicate the existence of particles beyond the standard model [4, 5, 6, 7, 8, 9, 10, 11]. If a resonant state exists at high mass, it will interfere with the SM amplitudes and will cause the to have a structure near the mass of the new state. Therefore, studying at high mass is particularly useful in a search for resonances that might be missed by a search using the dilepton mass spectrum alone.

The measurement presented in Ref. [3] and the measurement are complementary. The electroweak mixing parameter was measured within the framework of the SM using events in a dimuon mass window of –100\GeV, while in the current analysis we test the SM and look for signs of new physics at high dilepton mass. The electroweak mixing angle measurement was performed in the dimuon channel. Here we present the results of a measurement of with more data, the addition of the dielectron channel, and the combination of the two channels, as a function of mass in a wide mass range and in separate rapidity bins.

To study the forward-backward asymmetry, we use the Collins–Soper frame [12], in which is defined to be the angle between the lepton momentum and the axis that bisects the angle between the direction of one proton and the direction opposite to the other proton in the centre-of-mass frame of the dilepton. Use of this frame reduces the uncertainties due to the unknown transverse momentum of the incoming quarks. The sign of the longitudinal boost of the dilepton system is used to define the orientation of the Collins–Soper frame. The angle is calculated from quantities measured in the lab frame as {linenomath}


where is the four-momentum of the dilepton and and are the transverse and longitudinal components of the dilepton momentum with respect to the beam axis; () represents the four-momentum of the lepton (antilepton); and . The quark direction is not determined a priori at the Large Hadron Collider (LHC) [13] because both beams consist of protons. However, because the antiquark is necessarily a sea quark, on average we expect it to carry less momentum than the valence quark, and therefore the dilepton system is usually boosted in the direction of the valence quark [5, 14, 15]. This assumption is taken into account by including the sign of the longitudinal boost in the definition of . The forward-backward asymmetry is dependent on the dilepton rapidity, , where and refer to the energy and the third component of the momentum of the dilepton, respectively.

The raw measurement is distorted compared to the parton-level asymmetry, mainly because of the dilepton mass resolution of the detector and final-state electromagnetic radiation (FSR). The asymmetry is further distorted by the detector acceptance and diluted by the imperfect knowledge of the quark direction at the LHC. In this Letter we present the measurements unfolded to the electroweak vertex (Born level), taking into account the FSR, mass resolution, and other detector effects. The results are not corrected for the dilution effects due to the acceptance and unknown quark direction because such corrections require information that is not directly observable.

This analysis is based on a data sample of 5\fbinvcollected with the Compact Muon Solenoid (CMS) detector in 2011 at a centre-of-mass energy of 7\TeV. A detailed description of the CMS detector can be found in [16]. The central feature of the CMS detector is a 3.8\unitT superconducting solenoid of 6\unitm internal diameter. The silicon pixel and strip tracker, the crystal electromagnetic calorimeter (ECAL), and the brass/scintillator hadron calorimeter are located inside this solenoid. Muons are measured in the pseudorapidity window using the tracker and the muon system, which is instrumented with detection planes of three complementary technologies embedded in the steel return yoke of the magnet: drift tube chambers (DT), cathode strip chambers (CSC), and resistive plate chambers (RPC) [17]. Pseudorapidity is defined as , where the polar angle is measured with respect to the anticlockwise-beam direction. The DT technology is used in the barrel (), and CSC in the endcaps (). These are complemented by an RPC system that covers both regions up to . Electrons are detected as energy clusters in the ECAL and as tracks in the silicon tracker. The ECAL consists of nearly 76 000 lead tungstate crystals, which provide coverage in pseudorapidity in the barrel region and in the two endcap regions.

The signal (, \Pep\Pem) and the process, which is considered as a background in this analysis, are simulated using \POWHEG[18, 19, 20] at next-to-leading order (NLO). Parton showering is simulated using \PYTHIAv6.4.24 [21] with tune Z2, while the NLO parton distribution function (PDF) is CT10 [22]. The \PW+jets and background events are generated using \MADGRAPH [23] and \PYTHIA; the \TAUOLApackage is used to describe decays [24]. Event samples of \PW\PW, \PW\cPZ, \cPZ\cPZ, and QCD multijet backgrounds are generated using \PYTHIA. The generated events are processed with the \GEANTfour-based [25, 26] CMS detector simulation and reconstructed with the same software as the collision data. The signal MC samples include pileup conditions (multiple \Pp\Pp interactions occurring in the same bunch crossing) matching those observed in the 2011 data sample.

For data taken in the earlier part of 2011, the dimuon analysis is based on triggers that select events containing at least two muons, each with transverse momentum of at least 6 or at least 7\GeV, depending on the running period. For the later running period, the triggers select events containing two muons, one with \GeVor 17\GeVand the other with \GeV. Within a CSC or DT muon chamber, the hits in the multiple detection layers are fitted to a straight line representing a segment of the muon track. In the offline analysis, tracks reconstructed from hits in the silicon tracker are matched to tracks reconstructed from muon segments alone, and then the individual hits in the tracker and muon detectors are refitted to an overall track. In addition, to increase the acceptance for low momentum muons that may not penetrate deeply into the muon system, tracks from the silicon tracker are extrapolated into the muon system and any that match at least one muon chamber track segment are taken to be muon candidates. In both cases, multiple scattering and energy loss are taken into account as muons traverse the CMS detector. Well-reconstructed muons are selected by requiring (1) at least 10 hits in the tracker, including at least one in the pixel detector; (2) at least one segment in the muon system; (3) a normalized for the overall muon fit (if used); and (4) a transverse distance of closest approach to the beam axis of less than 2 mm. Cosmic ray muons that traverse CMS close to the interaction point can appear as back-to-back dimuons, but these are removed by requiring the muon pairs to have an acollinearity greater than 2.5\unitmrad. Each muon is required to be isolated from other charged tracks based on tracker information alone. No attempt is made to use radiated photons detected in ECAL to correct muon energies for FSR. The unfolding procedure corrects for the effect of FSR on on a statistical basis. More details on muon reconstruction and identification can be found in Ref. [27]. Trigger efficiency factors are calculated and applied for different data-taking periods. Each muon is required to be within the acceptance of the muon system () and have . Events are selected in which opposite-charge muon pairs meet the above requirements.

Dielectron candidates are selected online by requiring two ECAL clusters, each with transverse energy exceeding a threshold value. Offline reconstruction of electrons starts by building superclusters in the ECAL in order to collect the energy radiated by bremsstrahlung in the tracker material, following the procedure described in Ref. [28]. A specialized tracking algorithm is used to accommodate changes of curvature due to bremsstrahlung. Superclusters are then matched to electron tracks. Electron candidates are required to have a minimum supercluster of 20\GeVafter ECAL energy-scale corrections. Electrons are restricted to the same phase space as the muons, defined by \GeVand , for an unambiguous comparison and combination of the two channels. In order to avoid the inhomogeneous response at the interfaces between the ECAL barrel and endcaps, electrons are further required to fall within the pseudorapidity ranges or . Electrons are identified by means of shower shape variables, and electron isolation criteria are based on a variable that combines the tracker and calorimeter measurements. Electrons arising from photon conversions are suppressed by requiring that there be no missing tracker hits before the first hit on the reconstructed track matched to the electron, and also by rejecting a candidate if it forms a pair with a nearby track that is consistent with a conversion. More details on electron reconstruction and identification can be found in Ref. [29]. Energy scale, resolution, and efficiency factors are calculated and applied for different data-taking periods. Energy scale and resolution factors are derived using tests, taking the MC dielectron mass distribution as a constraint. Events are selected in which opposite-charge electron pairs meet the above requirements.

For both lepton channels, the main sources of background are and QCD dijets for the low mass region and for the high mass region. Diboson (\PW\PW, \PW\cPZ, and \cPZ\cPZ) and inclusive \PW production processes are lesser sources of background. Because some QCD jets can pass the electron identification criteria, the QCD background contribution is non-negligible in the dielectron channel below the \cPZ peak. Electroweak backgrounds are estimated using MC samples. For both channels, QCD background is estimated from the data under the assumption that same-sign and opposite-sign lepton pairs are equally probable because the misidentification of a charged particle in a jet as a lepton or antilepton is equally likely. Backgrounds are estimated for forward and backward events separately and subtracted bin by bin. The total background contribution to the data ranges from 0.17% to 0.21% in the dimuon channel and from 0.68% to 0.80% in the dielectron channel. After background subtraction, the numbers of events found in the muon channel in the forward and backward regions are 950 570 and 929 737, respectively. The corresponding numbers in the electron channel are 448 338 and 438 035.

All results are given in the phase-space region defined by and . We calculate the distributions in ten bins of dilepton mass and four bins of rapidity , the limits of which are defined to be , 50, 60, 76, 86, 96, 106, 120, 150, 200, and 2000\GeVand , 1.00, 1.25, 1.50, and 2.40.

The forward-backward asymmetry is diluted by the events in which the assumed quark and antiquark directions are incorrect. The asymmetry is further reduced by the acceptance requirements. No corrections are applied for either of these effects. The bin has the largest asymmetry dilution due to the unknown quark direction, but the smallest acceptance effect. The next two bins, and , have the largest asymmetry. The highest rapidity bin, , is least affected by the unknown quark direction but suffers a large acceptance reduction resulting in a smaller asymmetry compared to other bins.

To correct for FSR, mass resolution, efficiencies, and other detector effects, we unfold the forward and backward mass spectra in each bin. The unfolding procedure is performed using a matrix inversion technique [30]. The unfolding is performed with response matrices that provide a mapping between the corrected and measured numbers of events in each mass and rapidity bin: {linenomath}


In these equations, and refer to the number of forward () and backward () events within the acceptance (\GeVand ) in each mass bin  for the rapidity bin ; is the response matrix describing the transfer of forward events from generated mass bin  to observed mass bin , while is the response matrix for the backward events. We construct the response matrices for unfolding the reconstructed forward and backward mass spectra in each bin to the Born level. The response matrices are calculated using MC events before and after simulation of FSR and the detector effects. Therefore they account for the FSR and mass resolution as well as the efficiency within the detector acceptance. In the dielectron channel, the gap in ECAL in the pseudorapidity range of is treated as an inefficiency and corrected by the unfolding procedure. The response matrices that represent the forward generated but backward reconstructed events (and vice versa) have a negligible contribution and are not used in this study, but the effect of this approximation is taken into account in the systematic uncertainties. The unfolded values are obtained by inverting the above equations. The corresponding uncertainties are calculated taking into account the correlations due to the unfolding procedure. The estimated uncertainties are verified by applying the procedure to a large number of independent MC samples. These MC samples are also used to check whether there is a bias in the values obtained through unfolding, and the maximum difference in is found to be 0.06.

Systematic uncertainties are estimated in each - bin using MC events. All systematic uncertainties are assumed to be independent and are combined in quadrature.

Although the background is small in the Drell–Yan process, uncertainties in the background estimation lead to systematic errors in the final results. We take a conservative approach and assume that this small background is uncertain by 100%, and therefore scale the background up and down by 100% and repeat the analysis. The largest difference from the nominal is found to be . The systematic uncertainty in the background estimate in all other bins is smaller than .

To quantify possible systematic uncertainties that could arise from the modelling of FSR in \PYTHIA, we examine the events that show the largest change in lepton momentum pre- and post-radiation. The \PYTHIAdescription of FSR agrees with data to within 5%, so we reweight by 5% the events for which the difference of the momenta of a lepton pre- and post-radiation is larger than 1\GeV. The distributions obtained from the reweighted events are used to obtain new values for . Even such a large change in event weights results in a change in the value of of less than 0.02. These changes in the value of are assigned as systematic uncertainties arising from uncertainty in the modelling of FSR.

The systematic uncertainties related to detector alignment are studied using MC samples with different assumed tracker reconstruction geometries (basic distortions) based on the cylindrical symmetry of the tracker system [31]. The differences between the values obtained with the ideal geometry and the other scenarios are evaluated. For each - bin, the largest difference is taken as the alignment uncertainty. The largest of these uncertainties over the entire - range is 0.01.

In the dielectron channel, the uncertainties obtained from the minimization used to obtain the energy-scale and resolution factors are used to modify the energy scale and hence calculate the associated uncertainties. In the dimuon channel, no energy scale or resolution factors are applied, but to account for a possible scale uncertainty the energy scale is changed by 0.1% and the analysis is repeated. The resulting mass shift is found to be negligible. The largest systematic uncertainty due to energy scale and resolution is found to be 0.02 in .

The trigger efficiency uncertainties are estimated by comparing the results before and after trigger scale factors are applied for both channels. The uncertainties due to pileup are estimated by comparing results with different pileup multiplicity profiles for both channels. The efficiency uncertainties are found to be smaller than 0.005 and the pileup reweighting uncertainties smaller than 0.03 in .

The resulting total experimental systematic uncertainty is at most 0.1 in ; however, for most of the bins the total experimental uncertainty is less than 0.05.

The total experimental systematic uncertainty does not include the PDF or uncertainties. To determine these, we follow the recommendation of the PDF4LHC working group [32, 33]. At the NLO level, the recommendation is to reweight a sample generated with the CT10 PDF set [34, 22] to obtain samples that mimic the NNPDF2.1 [35] and MSTW2008 [36] PDFs. The internal degrees of freedom of each PDF set are varied. Samples corresponding to different assumptions are obtained in a similar manner. The value of is calculated in each - bin for each variation. The resulting variations in are combined to obtain the PDF uncertainty, following the PDF4LHC prescription. The largest uncertainty is found to be 0.012.

The unfolded AFB distributions at the Born level for the dimuon and dielectron channels are shown in Fig. 1. The measurements in the two channels agree well with each other. The unfolded and combined distributions at the Born level are displayed in Fig. 2 and Table Forward-backward asymmetry of Drell–Yan lepton pairs in pp collisions at 7\TeV. All these distributions are in agreement with the SM expectations and there is no indication of non-SM physics. The reversal of the sign of near the \cPZ peak is due to the change of sign of the \cPZ- interference term. The asymmetry is already evident at the raw level, before unfolding, and the bins that are most affected by unfolding are those just below and just above the \cPZ peak. Table Forward-backward asymmetry of Drell–Yan lepton pairs in pp collisions at 7\TeV also shows the difference of the unfolded and raw asymmetries in each bin. Table Forward-backward asymmetry of Drell–Yan lepton pairs in pp collisions at 7\TeV shows the estimated systematic uncertainties in each rapidity bin for the mass bin around the Z peak.

Figure 1: The unfolded and measurements of at the Born level in four bins for and . The data points are shown with statistical error bars.
Figure 2: The unfolded and combined ( and ) measurement of at the Born level in four bins for and . The data points are shown with both statistical error bars and combined statistical and systematic error bars. The error bars on the MC points represent the quadratically summed PDF uncertainties and statistical errors. The horizontal extent of the error bars indicates the bin width (except for the last bin, which is truncated at 400\GeV). Beneath each plot is shown the difference between data and MC, normalized by the combined statistical and systematic uncertainty. The green and yellow bands indicate the and differences of data from theory predictions.

Unfolded combined measurements of in each - bin. The average mass in each bin is shown, together with the measured and the corresponding statistical, systematic, and total uncertainties. The statistical and systematic errors are combined in quadrature to obtain the total uncertainties. The values estimated from MC are also shown, with the corresponding statistical and PDF uncertainties. The final column shows the larger of the differences in the muon and electron channels.

\absy M [\GeVns] [\GeVns] (data) stat. err. syst. err. tot. err. (MC) stat. err. (MC) PDF err. Unfolding

Estimated systematic uncertainties on , in units of , for each rapidity bin, in the mass bin around the \cPZ peak, –96\GeV. The components are discussed in the text. 0–1 1–1.25 1.25–1.5 1.5–2.4 FSR 0.1 +0.4/ +0.8/ +6.2/ Energy scale 0.1 +0.4/ +0.9/ +0.3/ Resolution +0.1/ +0.6/ 0.2 +0.0/ Alignment +0.4/ +0.5/ +0.7/ +0.0/ Background 0.1 0.1 0.1 0.1 Pileup and Eff. +0.2/ +0.3/ +1.9/ +0.5/ Unfolding +0.1/ +3.5/ +1.4/ +1.1/ PDFs 0.6 0.4 1.4 1.4

In summary, we have presented a measurement of the forward-backward asymmetry for opposite-charge lepton pairs produced via an intermediate Z/ at = 7\TeVin the CMS experiment, based on a sample of pp collisions corresponding to an integrated luminosity of 5\fbinv. The asymmetry is studied as a function of the dilepton rapidity and the dilepton mass for The unfolded and combined measurements at the Born level are presented. We find the distributions to be consistent with the standard model predictions. The measurement in the dimuon channel and the combination of the two channels are the first such results obtained at a hadron collider.


We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC machine. We thank the technical and administrative staff at CERN and other CMS institutes, and acknowledge support from: FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, 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); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA).

Appendix A The CMS Collaboration

Yerevan Physics Institute, Yerevan, Armenia
S. Chatrchyan, V. Khachatryan, A.M. Sirunyan, A. Tumasyan \cmsinstskipInstitut für Hochenergiephysik der OeAW, Wien, Austria
W. Adam, T. Bergauer, M. Dragicevic, J. Erö, C. Fabjan\cmsAuthorMark1, M. Friedl, R. Frühwirth\cmsAuthorMark1, V.M. Ghete, J. Hammer, N. Hörmann, J. Hrubec, M. Jeitler\cmsAuthorMark1, W. Kiesenhofer, V. Knünz, M. Krammer\cmsAuthorMark1, D. Liko, I. Mikulec, M. Pernicka, B. Rahbaran, C. Rohringer, H. Rohringer, R. Schöfbeck, J. Strauss, A. Taurok, P. Wagner, W. Waltenberger, G. Walzel, E. Widl, C.-E. Wulz\cmsAuthorMark1 \cmsinstskipNational Centre for Particle and High Energy Physics, Minsk, Belarus
V. Mossolov, N. Shumeiko, J. Suarez Gonzalez \cmsinstskipUniversiteit Antwerpen, Antwerpen, Belgium
S. Bansal, T. Cornelis, E.A. De Wolf, X. Janssen, S. Luyckx, T. Maes, L. Mucibello, S. Ochesanu, B. Roland, R. Rougny, M. Selvaggi, Z. Staykova, H. Van Haevermaet, P. Van Mechelen, N. Van Remortel, A. Van Spilbeeck \cmsinstskipVrije Universiteit Brussel, Brussel, Belgium
F. Blekman, S. Blyweert, J. D’Hondt, R. Gonzalez Suarez, A. Kalogeropoulos, M. Maes, A. Olbrechts, W. Van Doninck, P. Van Mulders, G.P. Van Onsem, I. Villella \cmsinstskipUniversité Libre de Bruxelles, Bruxelles, Belgium
B. Clerbaux, G. De Lentdecker, V. Dero, A.P.R. Gay, T. Hreus, A. Léonard, P.E. Marage, T. Reis, L. Thomas, C. Vander Velde, P. Vanlaer, J. Wang \cmsinstskipGhent University, Ghent, Belgium
V. Adler, K. Beernaert, A. Cimmino, S. Costantini, G. Garcia, M. Grunewald, B. Klein, J. Lellouch, A. Marinov, J. Mccartin, A.A. Ocampo Rios, D. Ryckbosch, N. Strobbe, F. Thyssen, M. Tytgat, L. Vanelderen, P. Verwilligen, S. Walsh, E. Yazgan, N. Zaganidis \cmsinstskipUniversité Catholique de Louvain, Louvain-la-Neuve, Belgium
S. Basegmez, G. Bruno, R. Castello, A. Caudron, L. Ceard, C. Delaere, T. du Pree, D. Favart, L. Forthomme, A. Giammanco\cmsAuthorMark2, J. Hollar, V. Lemaitre, J. Liao, O. Militaru, C. Nuttens, D. Pagano, L. Perrini, A. Pin, K. Piotrzkowski, N. Schul, J.M. Vizan Garcia \cmsinstskipUniversité de Mons, Mons, Belgium
N. Beliy, T. Caebergs, E. Daubie, G.H. Hammad \cmsinstskipCentro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil
G.A. Alves, M. Correa Martins Junior, D. De Jesus Damiao, T. Martins, M.E. Pol, M.H.G. Souza \cmsinstskipUniversidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
W.L. Aldá Júnior, W. Carvalho, A. Custódio, E.M. Da Costa, C. De Oliveira Martins, S. Fonseca De Souza, D. Matos Figueiredo, L. Mundim, H. Nogima, V. Oguri, W.L. Prado Da Silva, A. Santoro, L. Soares Jorge, A. Sznajder \cmsinstskipInstituto de Fisica Teorica, Universidade Estadual Paulista, Sao Paulo, Brazil
C.A. Bernardes\cmsAuthorMark3, F.A. Dias\cmsAuthorMark4, T.R. Fernandez Perez Tomei, E. M. Gregores\cmsAuthorMark3, C. Lagana, F. Marinho, P.G. Mercadante\cmsAuthorMark3, S.F. Novaes, Sandra S. Padula \cmsinstskipInstitute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria
V. Genchev\cmsAuthorMark5, P. Iaydjiev\cmsAuthorMark5, S. Piperov, M. Rodozov, S. Stoykova, G. Sultanov, V. Tcholakov, R. Trayanov, M. Vutova \cmsinstskipUniversity of Sofia, Sofia, Bulgaria
A. Dimitrov, R. Hadjiiska, V. Kozhuharov, L. Litov, B. Pavlov, P. Petkov \cmsinstskipInstitute of High Energy Physics, Beijing, China
J.G. Bian, G.M. Chen, H.S. Chen, C.H. Jiang, D. Liang, S. Liang, X. Meng, J. Tao, J. Wang, X. Wang, Z. Wang, H. Xiao, M. Xu, J. Zang, Z. Zhang \cmsinstskipState Key Lab. of Nucl. Phys. and Tech.,  Peking University, Beijing, China
C. Asawatangtrakuldee, Y. Ban, S. Guo, Y. Guo, W. Li, S. Liu, Y. Mao, S.J. Qian, H. Teng, S. Wang, B. Zhu, W. Zou \cmsinstskipUniversidad de Los Andes, Bogota, Colombia
C. Avila, J.P. Gomez, B. Gomez Moreno, A.F. Osorio Oliveros, J.C. Sanabria \cmsinstskipTechnical University of Split, Split, Croatia
N. Godinovic, D. Lelas, R. Plestina\cmsAuthorMark6, D. Polic, I. Puljak\cmsAuthorMark5 \cmsinstskipUniversity of Split, Split, Croatia
Z. Antunovic, M. Kovac \cmsinstskipInstitute Rudjer Boskovic, Zagreb, Croatia
V. Brigljevic, S. Duric, K. Kadija, J. Luetic, S. Morovic \cmsinstskipUniversity of Cyprus, Nicosia, Cyprus
A. Attikis, M. Galanti, G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis \cmsinstskipCharles University, Prague, Czech Republic
M. Finger, M. Finger Jr. \cmsinstskipAcademy of Scientific Research and Technology of the Arab Republic of Egypt, Egyptian Network of High Energy Physics, Cairo, Egypt
Y. Assran\cmsAuthorMark7, S. Elgammal\cmsAuthorMark8, A. Ellithi Kamel\cmsAuthorMark9, S. Khalil\cmsAuthorMark8, M.A. Mahmoud\cmsAuthorMark10, A. Radi\cmsAuthorMark11\cmsAuthorMark12 \cmsinstskipNational Institute of Chemical Physics and Biophysics, Tallinn, Estonia
M. Kadastik, M. Müntel, M. Raidal, L. Rebane, A. Tiko \cmsinstskipDepartment of Physics, University of Helsinki, Helsinki, Finland
V. Azzolini, P. Eerola, G. Fedi, M. Voutilainen \cmsinstskipHelsinki Institute of Physics, Helsinki, Finland
J. Härkönen, A. Heikkinen, V. Karimäki, R. Kinnunen, M.J. Kortelainen, T. Lampén, K. Lassila-Perini, S. Lehti, T. Lindén, P. Luukka, T. Mäenpää, T. Peltola, E. Tuominen, J. Tuominiemi, E. Tuovinen, D. Ungaro, L. Wendland \cmsinstskipLappeenranta University of Technology, Lappeenranta, Finland
K. Banzuzi, A. Karjalainen, A. Korpela, T. Tuuva \cmsinstskipDSM/IRFU, CEA/Saclay, Gif-sur-Yvette, France
M. Besancon, S. Choudhury, M. Dejardin, D. Denegri, B. Fabbro, J.L. Faure, F. Ferri, S. Ganjour, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, E. Locci, J. Malcles, L. Millischer, A. Nayak, J. Rander, A. Rosowsky, I. Shreyber, M. Titov \cmsinstskipLaboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France
S. Baffioni, F. Beaudette, L. Benhabib, L. Bianchini, M. Bluj\cmsAuthorMark13, C. Broutin, P. Busson, C. Charlot, N. Daci, T. Dahms, L. Dobrzynski, R. Granier de Cassagnac, M. Haguenauer, P. Miné, C. Mironov, M. Nguyen, C. Ochando, P. Paganini, D. Sabes, R. Salerno, Y. Sirois, C. Veelken, A. Zabi \cmsinstskipInstitut Pluridisciplinaire Hubert Curien, Université de Strasbourg, Université de Haute Alsace Mulhouse, CNRS/IN2P3, Strasbourg, France
J.-L. Agram\cmsAuthorMark14, J. Andrea, D. Bloch, D. Bodin, J.-M. Brom, M. Cardaci, E.C. Chabert, C. Collard, E. Conte\cmsAuthorMark14, F. Drouhin\cmsAuthorMark14, C. Ferro, J.-C. Fontaine\cmsAuthorMark14, D. Gelé, U. Goerlach, P. Juillot, A.-C. Le Bihan, P. Van Hove \cmsinstskipCentre de Calcul de l’Institut National de Physique Nucleaire et de Physique des Particules (IN2P3),  Villeurbanne, France
F. Fassi, D. Mercier \cmsinstskipUniversité de Lyon, Université Claude Bernard Lyon 1,  CNRS-IN2P3, Institut de Physique Nucléaire de Lyon, Villeurbanne, France
S. Beauceron, N. Beaupere, O. Bondu, G. Boudoul, J. Chasserat, R. Chierici\cmsAuthorMark5, D. Contardo, P. Depasse, H. El Mamouni, J. Fay, S. Gascon, M. Gouzevitch, B. Ille, T. Kurca, M. Lethuillier, L. Mirabito, S. Perries, V. Sordini, S. Tosi, Y. Tschudi, P. Verdier, S. Viret \cmsinstskipInstitute of High Energy Physics and Informatization, Tbilisi State University, Tbilisi, Georgia
Z. Tsamalaidze\cmsAuthorMark15 \cmsinstskipRWTH Aachen University, I. Physikalisches Institut, Aachen, Germany
G. Anagnostou, S. Beranek, M. Edelhoff, L. Feld, N. Heracleous, O. Hindrichs, R. Jussen, K. Klein, J. Merz, A. Ostapchuk, A. Perieanu, F. Raupach, J. Sammet, S. Schael, D. Sprenger, H. Weber, B. Wittmer, V. Zhukov\cmsAuthorMark16 \cmsinstskipRWTH Aachen University, III. Physikalisches Institut A,  Aachen, Germany
M. Ata, J. Caudron, E. Dietz-Laursonn, D. Duchardt, M. Erdmann, R. Fischer, A. Güth, T. Hebbeker, C. Heidemann, K. Hoepfner, D. Klingebiel, P. Kreuzer, J. Lingemann, C. Magass, M. Merschmeyer, A. Meyer, M. Olschewski, P. Papacz, H. Pieta, H. Reithler, S.A. Schmitz, L. Sonnenschein, J. Steggemann, D. Teyssier, M. Weber \cmsinstskipRWTH Aachen University, III. Physikalisches Institut B,  Aachen, Germany
M. Bontenackels, V. Cherepanov, G. Flügge, H. Geenen, M. Geisler, W. Haj Ahmad, F. Hoehle, B. Kargoll, T. Kress, Y. Kuessel, A. Nowack, L. Perchalla, O. Pooth, J. Rennefeld, P. Sauerland, A. Stahl \cmsinstskipDeutsches Elektronen-Synchrotron, Hamburg, Germany
M. Aldaya Martin, J. Behr, W. Behrenhoff, U. Behrens, M. Bergholz\cmsAuthorMark17, A. Bethani, K. Borras, A. Burgmeier, A. Cakir, L. Calligaris, A. Campbell, E. Castro, F. Costanza, D. Dammann, C. Diez Pardos, G. Eckerlin, D. Eckstein, G. Flucke, A. Geiser, I. Glushkov, P. Gunnellini, S. Habib, J. Hauk, G. Hellwig, H. Jung, M. Kasemann, P. Katsas, C. Kleinwort, H. Kluge, A. Knutsson, M. Krämer, D. Krücker, E. Kuznetsova, W. Lange, W. Lohmann\cmsAuthorMark17, B. Lutz, R. Mankel, I. Marfin, M. Marienfeld, I.-A. Melzer-Pellmann, A.B. Meyer, J. Mnich, A. Mussgiller, S. Naumann-Emme, J. Olzem, H. Perrey, A. Petrukhin, D. Pitzl, A. Raspereza, P.M. Ribeiro Cipriano, C. Riedl, E. Ron, M. Rosin, J. Salfeld-Nebgen, R. Schmidt\cmsAuthorMark17, T. Schoerner-Sadenius, N. Sen, A. Spiridonov, M. Stein, R. Walsh, C. Wissing \cmsinstskipUniversity of Hamburg, Hamburg, Germany
C. Autermann, V. Blobel, S. Bobrovskyi, J. Draeger, H. Enderle, J. Erfle, U. Gebbert, M. Görner, T. Hermanns, R.S. Höing, K. Kaschube, G. Kaussen, H. Kirschenmann, R. Klanner, J. Lange, B. Mura, F. Nowak, T. Peiffer, N. Pietsch, D. Rathjens, C. Sander, H. Schettler, P. Schleper, E. Schlieckau, A. Schmidt, M. Schröder, T. Schum, M. Seidel, H. Stadie, G. Steinbrück, J. Thomsen \cmsinstskipInstitut für Experimentelle Kernphysik, Karlsruhe, Germany
C. Barth, J. Berger, C. Böser, T. Chwalek, W. De Boer, A. Descroix, A. Dierlamm, M. Feindt, M. Guthoff\cmsAuthorMark5, C. Hackstein, F. Hartmann, T. Hauth\cmsAuthorMark5, M. Heinrich, H. Held, K.H. Hoffmann, S. Honc, I. Katkov\cmsAuthorMark16, J.R. Komaragiri, D. Martschei, S. Mueller, Th. Müller, M. Niegel, A. Nürnberg, O. Oberst, A. Oehler, J. Ott, G. Quast, K. Rabbertz, F. Ratnikov, N. Ratnikova, S. Röcker, A. Scheurer, F.-P. Schilling, G. Schott, H.J. Simonis, F.M. Stober, D. Troendle, R. Ulrich, J. Wagner-Kuhr, S. Wayand, T. Weiler, M. Zeise \cmsinstskipInstitute of Nuclear Physics ”Demokritos”,  Aghia Paraskevi, Greece
G. Daskalakis, T. Geralis, S. Kesisoglou, A. Kyriakis, D. Loukas, I. Manolakos, A. Markou, C. Markou, C. Mavrommatis, E. Ntomari \cmsinstskipUniversity of Athens, Athens, Greece
L. Gouskos, T.J. Mertzimekis, A. Panagiotou, N. Saoulidou \cmsinstskipUniversity of Ioánnina, Ioánnina, Greece
I. Evangelou, C. Foudas\cmsAuthorMark5, P. Kokkas, N. Manthos, I. Papadopoulos, V. Patras \cmsinstskipKFKI Research Institute for Particle and Nuclear Physics, Budapest, Hungary
G. Bencze, C. Hajdu\cmsAuthorMark5, P. Hidas, D. Horvath\cmsAuthorMark18, F. Sikler, V. Veszpremi, G. Vesztergombi\cmsAuthorMark19 \cmsinstskipInstitute of Nuclear Research ATOMKI, Debrecen, Hungary
N. Beni, S. Czellar, J. Molnar, J. Palinkas, Z. Szillasi \cmsinstskipUniversity of Debrecen, Debrecen, Hungary
J. Karancsi, P. Raics, Z.L. Trocsanyi, B. Ujvari \cmsinstskipPanjab University, Chandigarh, India
S.B. Beri, V. Bhatnagar, N. Dhingra, R. Gupta, M. Jindal, M. Kaur, M.Z. Mehta, N. Nishu, L.K. Saini, A. Sharma, J. Singh \cmsinstskipUniversity of Delhi, Delhi, India
Ashok Kumar, Arun Kumar, S. Ahuja, A. Bhardwaj, B.C. Choudhary, S. Malhotra, M. Naimuddin, K. Ranjan, V. Sharma, R.K. Shivpuri \cmsinstskipSaha Institute of Nuclear Physics, Kolkata, India
S. Banerjee, S. Bhattacharya, S. Dutta, B. Gomber, Sa. Jain, Sh. Jain, R. Khurana, S. Sarkar, M. Sharan \cmsinstskipBhabha Atomic Research Centre, Mumbai, India
A. Abdulsalam, R.K. Choudhury, D. Dutta, S. Kailas, V. Kumar, P. Mehta, A.K. Mohanty\cmsAuthorMark5, L.M. Pant, P. Shukla \cmsinstskipTata Institute of Fundamental Research - EHEP, Mumbai, India
T. Aziz, S. Ganguly, M. Guchait\cmsAuthorMark20, M. Maity\cmsAuthorMark21, G. Majumder, K. Mazumdar, G.B. Mohanty, B. Parida, K. Sudhakar, N. Wickramage \cmsinstskipTata Institute of Fundamental Research - HECR, Mumbai, India
S. Banerjee, S. Dugad \cmsinstskipInstitute for Research in Fundamental Sciences (IPM),  Tehran, Iran
H. Arfaei, H. Bakhshiansohi\cmsAuthorMark22, S.M. Etesami\cmsAuthorMark23, A. Fahim\cmsAuthorMark22, M. Hashemi, A. Jafari\cmsAuthorMark22, M. Khakzad, A. Mohammadi\cmsAuthorMark24, M. Mohammadi Najafabadi, S. Paktinat Mehdiabadi, B. Safarzadeh\cmsAuthorMark25, M. Zeinali\cmsAuthorMark23 \cmsinstskipINFN Sezione di Bari , Università di Bari , Politecnico di Bari ,  Bari, Italy
M. Abbrescia, L. Barbone, C. Calabria\cmsAuthorMark5, S.S. Chhibra, A. Colaleo, D. Creanza, N. De Filippis\cmsAuthorMark5, M. De Palma, L. Fiore, G. Iaselli, L. Lusito, G. Maggi, M. Maggi, B. Marangelli, S. My, S. Nuzzo, N. Pacifico, A. Pompili, G. Pugliese, G. Selvaggi, L. Silvestris, G. Singh, R. Venditti, G. Zito \cmsinstskipINFN Sezione di Bologna , Università di Bologna ,  Bologna, Italy
G. Abbiendi, A.C. Benvenuti, D. Bonacorsi, S. Braibant-Giacomelli, L. Brigliadori, P. Capiluppi, A. Castro, F.R. Cavallo, M. Cuffiani, G.M. Dallavalle, F. Fabbri, A. Fanfani, D. Fasanella\cmsAuthorMark5, P. Giacomelli, C. Grandi, L. Guiducci, S. Marcellini, G. Masetti, M. Meneghelli\cmsAuthorMark5, A. Montanari, F.L. Navarria, F. Odorici, A. Perrotta, F. Primavera, A.M. Rossi, T. Rovelli, G. Siroli, R. Travaglini \cmsinstskipINFN Sezione di Catania , Università di Catania ,  Catania, Italy
S. Albergo, G. Cappello, M. Chiorboli, S. Costa, R. Potenza, A. Tricomi, C. Tuve \cmsinstskipINFN Sezione di Firenze , Università di Firenze ,  Firenze, Italy
G. Barbagli, V. Ciulli, C. Civinini, R. D’Alessandro, E. Focardi, S. Frosali, E. Gallo, S. Gonzi, M. Meschini, S. Paoletti, G. Sguazzoni, A. Tropiano\cmsAuthorMark5 \cmsinstskipINFN Laboratori Nazionali di Frascati, Frascati, Italy
L. Benussi, S. Bianco, S. Colafranceschi\cmsAuthorMark26, F. Fabbri, D. Piccolo \cmsinstskipINFN Sezione di Genova, Genova, Italy
P. Fabbricatore, R. Musenich \cmsinstskipINFN Sezione di Milano-Bicocca , Università di Milano-Bicocca ,  Milano, Italy
A. Benaglia\cmsAuthorMark5, F. De Guio, L. Di Matteo\cmsAuthorMark5, S. Fiorendi, S. Gennai\cmsAuthorMark5, A. Ghezzi, S. Malvezzi, R.A. Manzoni, A. Martelli, A. Massironi\cmsAuthorMark5, D. Menasce, L. Moroni, M. Paganoni, D. Pedrini, S. Ragazzi, N. Redaelli, S. Sala, T. Tabarelli de Fatis \cmsinstskipINFN Sezione di Napoli , Università di Napoli ”Federico II” ,  Napoli, Italy
S. Buontempo, C.A. Carrillo Montoya\cmsAuthorMark5, N. Cavallo\cmsAuthorMark27, A. De Cosa\cmsAuthorMark5, O. Dogangun, F. Fabozzi\cmsAuthorMark27, A.O.M. Iorio, L. Lista, S. Meola\cmsAuthorMark28, M. Merola, P. Paolucci\cmsAuthorMark5 \cmsinstskipINFN Sezione di Padova , Università di Padova , Università di Trento (Trento) ,  Padova, Italy
P. Azzi, N. Bacchetta\cmsAuthorMark5, D. Bisello, A. Branca\cmsAuthorMark5, R. Carlin, P. Checchia, T. Dorigo, U. Dosselli, F. Gasparini, U. Gasparini, A. Gozzelino, K. Kanishchev, S. Lacaprara, I. Lazzizzera, M. Margoni, A.T. Meneguzzo, J. Pazzini, N. Pozzobon, P. Ronchese, F. Simonetto, E. Torassa, M. Tosi\cmsAuthorMark5, S. Vanini, P. Zotto, A. Zucchetta, G. Zumerle \cmsinstskipINFN Sezione di Pavia , Università di Pavia ,  Pavia, Italy
M. Gabusi, S.P. Ratti, C. Riccardi, P. Torre, P. Vitulo \cmsinstskipINFN Sezione di Perugia , Università di Perugia ,  Perugia, Italy
M. Biasini, G.M. Bilei, L. Fanò, P. Lariccia, A. Lucaroni\cmsAuthorMark5, G. Mantovani, M. Menichelli, A. Nappi, F. Romeo, A. Saha, A. Santocchia, S. Taroni\cmsAuthorMark5 \cmsinstskipINFN Sezione di Pisa , Università di Pisa , Scuola Normale Superiore di Pisa ,  Pisa, Italy
P. Azzurri, G. Bagliesi, T. Boccali, G. Broccolo, R. Castaldi, R.T. D’Agnolo, R. Dell’Orso, F. Fiori\cmsAuthorMark5, L. Foà, A. Giassi, A. Kraan, F. Ligabue, T. Lomtadze, L. Martini\cmsAuthorMark29, A. Messineo, F. Palla, A. Rizzi, A.T. Serban\cmsAuthorMark30, P. Spagnolo, P. Squillacioti\cmsAuthorMark5, R. Tenchini, G. Tonelli\cmsAuthorMark5, A. Venturi\cmsAuthorMark5, P.G. Verdini \cmsinstskipINFN Sezione di Roma , Università di Roma ”La Sapienza” ,  Roma, Italy
L. Barone, F. Cavallari, D. Del Re\cmsAuthorMark5, M. Diemoz, M. Grassi\cmsAuthorMark5, E. Longo, P. Meridiani\cmsAuthorMark5, F. Micheli, S. Nourbakhsh, G. Organtini, R. Paramatti, S. Rahatlou, M. Sigamani, L. Soffi \cmsinstskipINFN Sezione di Torino , Università di Torino , Università del Piemonte Orientale (Novara) ,  Torino, Italy
N. Amapane, R. Arcidiacono, S. Argiro, M. Arneodo, C. Biino, N. Cartiglia, M. Costa, N. Demaria, A. Graziano, C. Mariotti\cmsAuthorMark5, S. Maselli, E. Migliore, V. Monaco, M. Musich\cmsAuthorMark5, M.M. Obertino, N. Pastrone, M. Pelliccioni, A. Potenza, A. Romero, M. Ruspa, R. Sacchi, V. Sola, A. Solano, A. Staiano, A. Vilela Pereira \cmsinstskipINFN Sezione di Trieste , Università di Trieste ,  Trieste, Italy
S. Belforte, V. Candelise, F. Cossutti, G. Della Ricca, B. Gobbo, M. Marone\cmsAuthorMark5, D. Montanino\cmsAuthorMark5, A. Penzo, A. Schizzi \cmsinstskipKangwon National University, Chunchon, Korea
S.G. Heo, T.Y. Kim, S.K. Nam \cmsinstskipKyungpook National University, Daegu, Korea
S. Chang, J. Chung, D.H. Kim, G.N. Kim, D.J. Kong, H. Park, S.R. Ro, D.C. Son, T. Son \cmsinstskipChonnam National University, Institute for Universe and Elementary Particles, Kwangju, Korea
J.Y. Kim, Zero J. Kim, S. Song \cmsinstskipKorea University, Seoul, Korea
S. Choi, D. Gyun, B. Hong, M. Jo, H. Kim, T.J. Kim, K.S. Lee, D.H. Moon, S.K. Park \cmsinstskipUniversity of Seoul, Seoul, Korea
M. Choi, S. Kang, J.H. Kim, C. Park, I.C. Park, S. Park, G. Ryu \cmsinstskipSungkyunkwan University, Suwon, Korea
Y. Cho, Y. Choi, Y.K. Choi, J. Goh, M.S. Kim, E. Kwon, B. Lee, J. Lee, S. Lee, H. Seo, I. Yu \cmsinstskipVilnius University, Vilnius, Lithuania
M.J. Bilinskas, I. Grigelionis, M. Janulis, A. Juodagalvis \cmsinstskipCentro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico
H. Castilla-Valdez, E. De La Cruz-Burelo, I. Heredia-de La Cruz, R. Lopez-Fernandez, R. Magaña Villalba, J. Martínez-Ortega, A. Sánchez-Hernández, L.M. Villasenor-Cendejas \cmsinstskipUniversidad Iberoamericana, Mexico City, Mexico
S. Carrillo Moreno, F. Vazquez Valencia \cmsinstskipBenemerita Universidad Autonoma de Puebla, Puebla, Mexico
H.A. Salazar Ibarguen \cmsinstskipUniversidad Autónoma de San Luis Potosí,  San Luis Potosí,  Mexico
E. Casimiro Linares, A. Morelos Pineda, M.A. Reyes-Santos \cmsinstskipUniversity of Auckland, Auckland, New Zealand
D. Krofcheck \cmsinstskipUniversity of Canterbury, Christchurch, New Zealand
A.J. Bell, P.H. Butler, R. Doesburg, S. Reucroft, H. Silverwood \cmsinstskipNational Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan
M. Ahmad, M.I. Asghar, H.R. Hoorani, S. Khalid, W.A. Khan, T. Khurshid, S. Qazi, M.A. Shah, M. Shoaib \cmsinstskipInstitute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
G. Brona, K. Bunkowski, M. Cwiok, W. Dominik, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski \cmsinstskipSoltan Institute for Nuclear Studies, Warsaw, Poland
H. Bialkowska, B. Boimska, T. Frueboes, R. Gokieli, M. Górski, M. Kazana, K. Nawrocki, K. Romanowska-Rybinska, M. Szleper, G. Wrochna, P. Zalewski \cmsinstskipLaboratório de Instrumentação e Física Experimental de Partículas, Lisboa, Portugal
N. Almeida, P. Bargassa, A. David, P. Faccioli, M. Fernandes, P.G. Ferreira Parracho, M. Gallinaro, J. Seixas, J. Varela, P. Vischia \cmsinstskipJoint Institute for Nuclear Research, Dubna, Russia
I. Belotelov, I. Golutvin, I. Gorbunov, A. Kamenev, V. Karjavin, V. Konoplyanikov, G. Kozlov, A. Lanev, A. Malakhov, P. Moisenz, V. Palichik, V. Perelygin, M. Savina, S. Shmatov, V. Smirnov, A. Volodko, A. Zarubin \cmsinstskipPetersburg Nuclear Physics Institute, Gatchina (St Petersburg),  Russia
S. Evstyukhin, V. Golovtsov, Y. Ivanov, V. Kim, P. Levchenko, V. Murzin, V. Oreshkin, I. Smirnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev, An. Vorobyev \cmsinstskipInstitute for Nuclear Research, Moscow, Russia
Yu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, M. Kirsanov, N. Krasnikov, V. Matveev, A. Pashenkov, D. Tlisov, A. Toropin \cmsinstskipInstitute for Theoretical and Experimental Physics, Moscow, Russia
V. Epshteyn, M. Erofeeva, V. Gavrilov, M. Kossov\cmsAuthorMark5, N. Lychkovskaya, V. Popov, G. Safronov, S. Semenov, V. Stolin, E. Vlasov, A. Zhokin \cmsinstskipMoscow State University, Moscow, Russia
A. Belyaev, E. Boos, M. Dubinin\cmsAuthorMark4, L. Dudko, A. Ershov, A. Gribushin, V. Klyukhin, O. Kodolova, I. Lokhtin, A. Markina, S. Obraztsov, M. Perfilov, S. Petrushanko, A. Popov, L. Sarycheva, V. Savrin, A. Snigirev \cmsinstskipP.N. Lebedev Physical Institute, Moscow, Russia
V. Andreev, M. Azarkin, I. Dremin, M. Kirakosyan, A. Leonidov, G. Mesyats, S.V. Rusakov, A. Vinogradov \cmsinstskipState Research Center of Russian Federation, Institute for High Energy Physics, Protvino, Russia
I. Azhgirey, I. Bayshev, S. Bitioukov, V. Grishin\cmsAuthorMark5, V. Kachanov, D. Konstantinov, A. Korablev, V. Krychkine, V. Petrov, R. Ryutin, A. Sobol, L. Tourtchanovitch, S. Troshin, N. Tyurin, A. Uzunian, A. Volkov \cmsinstskipUniversity of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia
P. Adzic\cmsAuthorMark31, M. Djordjevic, M. Ekmedzic, D. Krpic\cmsAuthorMark31, J. Milosevic \cmsinstskipCentro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT),  Madrid, Spain
M. Aguilar-Benitez, J. Alcaraz Maestre, P. Arce, C. Battilana, E. Calvo, M. Cerrada, M. Chamizo Llatas, N. Colino, B. De La Cruz, A. Delgado Peris, D. Domínguez Vázquez, C. Fernandez Bedoya, J.P. Fernández 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, A. Quintario Olmeda, I. Redondo, L. Romero, J. Santaolalla, M.S. Soares, C. Willmott \cmsinstskipUniversidad Autónoma de Madrid, Madrid, Spain
C. Albajar, G. Codispoti, J.F. de Trocóniz \cmsinstskipUniversidad de Oviedo, Oviedo, Spain
H. Brun, J. Cuevas, J. Fernandez Menendez, S. Folgueras, I. Gonzalez Caballero, L. Lloret Iglesias, J. Piedra Gomez\cmsAuthorMark32 \cmsinstskipInstituto de Física de Cantabria (IFCA),  CSIC-Universidad de Cantabria, Santander, Spain
J.A. Brochero Cifuentes, I.J. Cabrillo, A. Calderon, S.H. Chuang, J. Duarte Campderros, M. Felcini\cmsAuthorMark33, M. Fernandez, G. Gomez, J. Gonzalez Sanchez, C. Jorda, P. Lobelle Pardo, A. Lopez Virto, J. Marco, R. Marco, C. Martinez Rivero, F. Matorras, F.J. Munoz Sanchez, T. Rodrigo, A.Y. Rodríguez-Marrero, A. Ruiz-Jimeno, L. Scodellaro, M. Sobron Sanudo, I. Vila, R. Vilar Cortabitarte \cmsinstskipCERN, European Organization for Nuclear Research, Geneva, Switzerland
D. Abbaneo, E. Auffray, G. Auzinger, P. Baillon, A.H. Ball, D. Barney, C. Bernet\cmsAuthorMark6, G. Bianchi, P. Bloch, A. Bocci, A. Bonato, C. Botta, H. Breuker, T. Camporesi, G. Cerminara, T. Christiansen, J.A. Coarasa Perez, D. D’Enterria, A. Dabrowski, A. De Roeck, S. Di Guida, M. Dobson, N. Dupont-Sagorin, A. Elliott-Peisert, B. Frisch, W. Funk, G. Georgiou, M. Giffels, D. Gigi, K. Gill, D. Giordano, M. Giunta, F. Glege, R. Gomez-Reino Garrido, P. Govoni, S. Gowdy, R. Guida, M. Hansen, P. Harris, C. Hartl, J. Harvey, B. Hegner, A. Hinzmann, V. Innocente, P. Janot, K. Kaadze, E. Karavakis, K. Kousouris, P. Lecoq, Y.-J. Lee, P. Lenzi, C. Lourenço, T. Mäki, M. Malberti, L. Malgeri, M. Mannelli, L. Masetti, F. Meijers, S. Mersi, E. Meschi, R. Moser, M.U. Mozer, M. Mulders, P. Musella, E. Nesvold, T. Orimoto, L. Orsini, E. Palencia Cortezon, E. Perez, L. Perrozzi, A. Petrilli, A. Pfeiffer, M. Pierini, M. Pimiä, D. Piparo, G. Polese, L. Quertenmont, A. Racz, W. Reece, J. Rodrigues Antunes, G. Rolandi\cmsAuthorMark34, T. Rommerskirchen, C. Rovelli\cmsAuthorMark35, M. Rovere, H. Sakulin, F. Santanastasio, C. Schäfer, C. Schwick, I. Segoni, S. Sekmen, A. Sharma, P. Siegrist, P. Silva, M. Simon, P. Sphicas\cmsAuthorMark36, D. Spiga, M. Spiropulu\cmsAuthorMark4, M. Stoye, A. Tsirou, G.I. Veres\cmsAuthorMark19, J.R. Vlimant, H.K. Wöhri, S.D. Worm\cmsAuthorMark37, W.D. Zeuner \cmsinstskipPaul Scherrer Institut, Villigen, Switzerland
W. Bertl, K. Deiters, W. Erdmann, K. Gabathuler, R. Horisberger, Q. Ingram, H.C. Kaestli, S. König, D. Kotlinski, U. Langenegger, F. Meier, D. Renker, T. Rohe, J. Sibille\cmsAuthorMark38 \cmsinstskipInstitute for Particle Physics, ETH Zurich, Zurich, Switzerland
L. Bäni, P. Bortignon, M.A. Buchmann, B. Casal, N. Chanon, A. Deisher, G. Dissertori, M. Dittmar, M. Dünser, J. Eugster, K. Freudenreich, C. Grab, D. Hits, P. Lecomte, W. Lustermann, A.C. Marini, P. Martinez Ruiz del Arbol, N. Mohr, F. Moortgat, C. Nägeli\cmsAuthorMark39, P. Nef, F. Nessi-Tedaldi, F. Pandolfi, L. Pape, F. Pauss, M. Peruzzi, F.J. Ronga, M. Rossini, L. Sala, A.K. Sanchez, A. Starodumov\cmsAuthorMark40, B. Stieger, M. Takahashi, L. Tauscher, A. Thea, K. Theofilatos, D. Treille, C. Urscheler, R. Wallny, H.A. Weber, L. Wehrli \cmsinstskipUniversität Zürich, Zurich, Switzerland
E. Aguilo, C. Amsler, V. Chiochia, S. De Visscher, C. Favaro, M. Ivova Rikova, B. Millan Mejias, P. Otiougova, P. Robmann, H. Snoek, S. Tupputi, M. Verzetti \cmsinstskipNational Central University, Chung-Li, Taiwan
Y.H. Chang, K.H. Chen, C.M. Kuo, S.W. Li, W. Lin, Z.K. Liu, Y.J. Lu, D. Mekterovic, A.P. Singh, R. Volpe, S.S. Yu \cmsinstskipNational Taiwan University (NTU),  Taipei, Taiwan
P. Bartalini, P. Chang, Y.H. Chang, Y.W. Chang, Y. Chao, K.F. Chen, C. Dietz, U. Grundler, W.-S. Hou, Y. Hsiung, K.Y. Kao, Y.J. Lei, R.-S. Lu, D. Majumder, E. Petrakou, X. Shi, J.G. Shiu, Y.M. Tzeng, X. Wan, M. Wang \cmsinstskipCukurova University, Adana, Turkey
A. Adiguzel, M.N. Bakirci\cmsAuthorMark41, S. Cerci\cmsAuthorMark42, C. Dozen, I. Dumanoglu, E. Eskut, S. Girgis, G. Gokbulut, E. Gurpinar, I. Hos, E.E. Kangal, G. Karapinar, A. Kayis Topaksu, G. Onengut, K. Ozdemir, S. Ozturk\cmsAuthorMark43, A. Polatoz, K. Sogut\cmsAuthorMark44, D. Sunar Cerci\cmsAuthorMark42, B. Tali\cmsAuthorMark42, H. Topakli\cmsAuthorMark41, L.N. Vergili, M. Vergili \cmsinstskipMiddle East Technical University, Physics Department, Ankara, Turkey
I.V. Akin, T. Aliev, B. Bilin, S. Bilmis, M. Deniz, H. Gamsizkan, A.M. Guler, K. Ocalan, A. Ozpineci, M. Serin, R. Sever, U.E. Surat, M. Yalvac, E. Yildirim, M. Zeyrek \cmsinstskipBogazici University, Istanbul, Turkey
E. Gülmez, B. Isildak\cmsAuthorMark45, M. Kaya\cmsAuthorMark46, O. Kaya\cmsAuthorMark46, S. Ozkorucuklu\cmsAuthorMark47, N. Sonmez\cmsAuthorMark48 \cmsinstskipIstanbul Technical University, Istanbul, Turkey
K. Cankocak \cmsinstskipNational Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, Ukraine
L. Levchuk \cmsinstskipUniversity of Bristol, Bristol, United Kingdom
F. Bostock, J.J. Brooke, E. Clement, D. Cussans, H. Flacher, R. Frazier, J. Goldstein, M. Grimes, G.P. Heath, H.F. Heath, L. Kreczko, S. Metson, D.M. Newbold\cmsAuthorMark37, K. Nirunpong, A. Poll, S. Senkin, V.J. Smith, T. Williams \cmsinstskipRutherford Appleton Laboratory, Didcot, United Kingdom
L. Basso\cmsAuthorMark49, K.W. Bell, A. Belyaev\cmsAuthorMark49, C. Brew, R.M. Brown, D.J.A. Cockerill, J.A. Coughlan, K. Harder, S. Harper, J. Jackson, B.W. Kennedy, E. Olaiya, D. Petyt, B.C. Radburn-Smith, C.H. Shepherd-Themistocleous, I.R. Tomalin, W.J. Womersley \cmsinstskipImperial College, London, United Kingdom
R. Bainbridge, G. Ball, R. Beuselinck, O. Buchmuller, D. Colling, N. Cripps, M. Cutajar, P. Dauncey, 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, A.-M. Magnan, J. Marrouche, B. Mathias, R. Nandi, J. Nash, A. Nikitenko\cmsAuthorMark40, A. Papageorgiou, J. Pela\cmsAuthorMark5, M. Pesaresi, K. Petridis, M. Pioppi\cmsAuthorMark50, D.M. Raymond, S. Rogerson, A. Rose, M.J. Ryan, C. Seez, P. Sharp, A. Sparrow, A. Tapper, M. Vazquez Acosta, T. Virdee, S. Wakefield, N. Wardle, T. Whyntie \cmsinstskipBrunel University, Uxbridge, United Kingdom
M. Chadwick, J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, D. Leggat, D. Leslie, W. Martin, I.D. Reid, P. Symonds, L. Teodorescu, M. Turner \cmsinstskipBaylor University, Waco, USA
K. Hatakeyama, H. Liu, T. Scarborough \cmsinstskipThe University of Alabama, Tuscaloosa, USA
O. Charaf, C. Henderson, P. Rumerio \cmsinstskipBoston University, Boston, USA
A. Avetisyan, T. Bose, C. Fantasia, A. Heister, J. St. John, P. Lawson, D. Lazic, J. Rohlf, D. Sperka, L. Sulak \cmsinstskipBrown University, Providence, USA
J. Alimena, S. Bhattacharya, D. Cutts, A. Ferapontov, U. Heintz, S. Jabeen, G. Kukartsev, E. Laird, G. Landsberg, M. Luk, M. Narain, D. Nguyen, M. Segala, T. Sinthuprasith, T. Speer, K.V. Tsang \cmsinstskipUniversity of California, Davis, Davis, USA
R. Breedon, G. Breto, M. Calderon De La Barca Sanchez, S. Chauhan, M. Chertok, J. Conway, R. Conway, P.T. Cox, J. Dolen, R. Erbacher, M. Gardner, R. Houtz, W. Ko, A. Kopecky, R. Lander, T. Miceli, D. Pellett, B. Rutherford, M. Searle, J. Smith, M. Squires, M. Tripathi, R. Vasquez Sierra \cmsinstskipUniversity of California, Los Angeles, Los Angeles, USA
V. Andreev, D. Cline, R. Cousins, J. Duris, S. Erhan, P. Everaerts, C. Farrell, J. Hauser, M. Ignatenko, C. Jarvis, C. Plager, G. Rakness, P. Schlein, J. Tucker, V. Valuev, M. Weber \cmsinstskipUniversity of California, Riverside, Riverside, USA
J. Babb, R. Clare, M.E. Dinardo, J. Ellison, J.W. Gary, F. Giordano, G. Hanson, G.Y. Jeng\cmsAuthorMark51, H. Liu, O.R. Long, A. Luthra, H. Nguyen, S. Paramesvaran, J. Sturdy, S. Sumowidagdo, R. Wilken, S. Wimpenny \cmsinstskipUniversity of California, San Diego, La Jolla, USA
W. Andrews, J.G. Branson, G.B. Cerati, S. Cittolin, D. Evans, F. Golf, A. Holzner, R. Kelley, M. Lebourgeois, J. Letts, I. Macneill, B. Mangano, S. Padhi, C. Palmer, G. Petrucciani, M. Pieri, M. Sani, V. Sharma, S. Simon, E. Sudano, M. Tadel, Y. Tu, A. Vartak, S. Wasserbaech\cmsAuthorMark52, F. Würthwein, A. Yagil, J. Yoo \cmsinstskipUniversity of California, Santa Barbara, Santa Barbara, USA
D. 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, C. West \cmsinstskipCalifornia Institute of Technology, Pasadena, USA
A. Apresyan, A. Bornheim, Y. Chen, E. Di Marco, J. Duarte, M. Gataullin, Y. Ma, A. Mott, H.B. Newman, C. Rogan, V. Timciuc, P. Traczyk, J. Veverka, R. Wilkinson, Y. Yang, R.Y. Zhu \cmsinstskipCarnegie Mellon University, Pittsburgh, USA
B. Akgun, R. Carroll, T. Ferguson, Y. Iiyama, D.W. Jang, Y.F. Liu, M. Paulini, H. Vogel, I. Vorobiev \cmsinstskipUniversity of Colorado at Boulder, Boulder, USA
J.P. Cumalat, B.R. Drell, C.J. Edelmaier, W.T. Ford, A. Gaz, B. Heyburn, E. Luiggi Lopez, J.G. Smith, K. Stenson, K.A. Ulmer, S.R. Wagner \cmsinstskipCornell University, Ithaca, USA
J. Alexander, A. Chatterjee, N. Eggert, L.K. Gibbons, B. Heltsley, A. Khukhunaishvili, B. Kreis, N. Mirman, G. Nicolas Kaufman, J.R. Patterson, A. Ryd, E. Salvati, W. Sun, W.D. Teo, J. Thom, J. Thompson, J. Vaughan, Y. Weng, L. Winstrom, P. Wittich \cmsinstskipFairfield University, Fairfield, USA
D. Winn \cmsinstskipFermi National Accelerator Laboratory, Batavia, USA
S. Abdullin, M. Albrow, J. Anderson, L.A.T. Bauerdick, A. Beretvas, J. Berryhill, P.C. Bhat, I. Bloch, K. Burkett, J.N. Butler, V. Chetluru, H.W.K. Cheung, F. Chlebana, V.D. Elvira, I. Fisk, J. Freeman, Y. Gao, D. Green, O. Gutsche, J. Hanlon, R.M. Harris, J. Hirschauer, B. Hooberman, S. Jindariani, M. Johnson, U. Joshi, B. Kilminster, B. Klima, S. Kunori, S. Kwan, C. Leonidopoulos, D. Lincoln, R. Lipton, J. Lykken, K. Maeshima, J.M. Marraffino, S. Maruyama, D. Mason, P. McBride, K. Mishra, S. Mrenna, Y. Musienko\cmsAuthorMark53, C. Newman-Holmes, V. O’Dell, O. Prokofyev, E. Sexton-Kennedy, S. Sharma, W.J. Spalding, L. Spiegel, P. Tan, L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger, E.W. Vaandering, R. Vidal, J. Whitmore, W. Wu, F. Yang, F. Yumiceva, J.C. Yun \cmsinstskipUniversity of Florida, Gainesville, USA
D. Acosta, P. Avery, D. Bourilkov, M. Chen, S. Das, M. De Gruttola, G.P. Di Giovanni, D. Dobur, A. Drozdetskiy, R.D. Field, M. Fisher, Y. Fu, I.K. Furic, J. Gartner, J. Hugon, B. Kim, J. Konigsberg, A. Korytov, A. Kropivnitskaya, T. Kypreos, J.F. Low, K. Matchev, P. Milenovic\cmsAuthorMark54, G. Mitselmakher, L. Muniz, R. Remington, A. Rinkevicius, P. Sellers, N. Skhirtladze, M. Snowball, J. Yelton, M. Zakaria \cmsinstskipFlorida International University, Miami, USA
V. Gaultney, L.M. Lebolo, S. Linn, P. Markowitz, G. Martinez, J.L. Rodriguez \cmsinstskipFlorida State University, Tallahassee, USA
J.R. Adams, T. Adams, A. Askew, J. Bochenek, J. Chen, B. Diamond, S.V. Gleyzer, J. Haas, S. Hagopian, V. Hagopian, M. Jenkins, K.F. Johnson, H. Prosper, V. Veeraraghavan, M. Weinberg \cmsinstskipFlorida Institute of Technology, Melbourne, USA
M.M. Baarmand, B. Dorney, M. Hohlmann, H. Kalakhety, I. Vodopiyanov \cmsinstskipUniversity of Illinois at Chicago (UIC),  Chicago, USA
M.R. Adams, I.M. Anghel, L. Apanasevich, Y. Bai, V.E. Bazterra, R.R. Betts, I. Bucinskaite, J. Callner, R. Cavanaugh, C. Dragoiu, O. Evdokimov, L. Gauthier, C.E. Gerber, D.J. Hofman, S. Khalatyan, F. Lacroix, M. Malek, C. O’Brien, C. Silkworth, D. Strom, N. Varelas \cmsinstskipThe University of Iowa, Iowa City, USA
U. Akgun, E.A. Albayrak, B. Bilki\cmsAuthorMark55, W. Clarida, F. Duru, S. Griffiths, J.-P. Merlo, H. Mermerkaya\cmsAuthorMark56, A. Mestvirishvili, A. Moeller, J. Nachtman, C.R. Newsom, E. Norbeck, Y. Onel, F. Ozok, S. Sen, E. Tiras, J. Wetzel, T. Yetkin, K. Yi \cmsinstskipJohns Hopkins University, Baltimore, USA
B.A. Barnett, B. Blumenfeld, S. Bolognesi, D. Fehling, G. Giurgiu, A.V. Gritsan, Z.J. Guo, G. Hu, P. Maksimovic, S. Rappoccio, M. Swartz, A. Whitbeck \cmsinstskipThe University of Kansas, Lawrence, USA
P. Baringer, A. Bean, G. Benelli, O. Grachov, R.P. Kenny Iii, M. Murray, D. Noonan, S. Sanders, R. Stringer, G. Tinti, J.S. Wood, V. Zhukova \cmsinstskipKansas State University, Manhattan, USA
A.F. Barfuss, T. Bolton, I. Chakaberia, A. Ivanov, S. Khalil, M. Makouski, Y. Maravin, S. Shrestha, I. Svintradze \cmsinstskipLawrence Livermore National Laboratory, Livermore, USA
J. Gronberg, D. Lange, D. Wright \cmsinstskipUniversity of Maryland, College Park, USA
A. Baden, M. Boutemeur, B. Calvert, S.C. Eno, J.A. Gomez, N.J. Hadley, R.G. Kellogg, M. Kirn, T. Kolberg, Y. Lu, M. Marionneau, A.C. Mignerey, K. Pedro, A. Peterman, A. Skuja, J. Temple, M.B. Tonjes, S.C. Tonwar, E. Twedt \cmsinstskipMassachusetts Institute of Technology, Cambridge, USA
G. Bauer, J. Bendavid, W. Busza, E. Butz, I.A. Cali, M. Chan, V. Dutta, G. Gomez Ceballos, M. Goncharov, K.A. Hahn, Y. Kim, M. Klute, K. Krajczar\cmsAuthorMark57, W. Li, P.D. Luckey, T. Ma, S. Nahn, C. Paus, D. Ralph, C. Roland, G. Roland, M. Rudolph, G.S.F. Stephans, F. Stöckli, K. Sumorok, K. Sung, D. Velicanu, E.A. Wenger, R. Wolf, B. Wyslouch, S. Xie, M. Yang, Y. Yilmaz, A.S. Yoon, M. Zanetti \cmsinstskipUniversity of Minnesota, Minneapolis, USA
S.I. Cooper, B. Dahmes, A. De Benedetti, G. Franzoni, A. Gude, S.C. Kao, K. Klapoetke, Y. Kubota, J. Mans, N. Pastika, R. Rusack, M. Sasseville, A. Singovsky, N. Tambe, J. Turkewitz \cmsinstskipUniversity of Mississippi, University, USA
L.M. Cremaldi, R. Kroeger, L. Perera, R. Rahmat, D.A. Sanders \cmsinstskipUniversity of Nebraska-Lincoln, Lincoln, USA
E. Avdeeva, K. Bloom, S. Bose, J. Butt, D.R. Claes, A. Dominguez, M. Eads, J. Keller, I. Kravchenko, J. Lazo-Flores, H. Malbouisson, S. Malik, G.R. Snow \cmsinstskipState University of New York at Buffalo, Buffalo, USA
U. Baur, A. Godshalk, I. Iashvili, S. Jain, A. Kharchilava, A. Kumar, S.P. Shipkowski, K. Smith \cmsinstskipNortheastern University, Boston, USA
G. Alverson, E. Barberis, D. Baumgartel, M. Chasco, J. Haley, D. Nash, D. Trocino, D. Wood, J. Zhang \cmsinstskipNorthwestern University, Evanston, USA
A. Anastassov, A. Kubik, N. Mucia, N. Odell, R.A. Ofierzynski, B. Pollack, A. Pozdnyakov, M. Schmitt, S. Stoynev, M. Velasco, S. Won \cmsinstskipUniversity of Notre Dame, Notre Dame, USA
L. Antonelli, D. Berry, A. Brinkerhoff, M. Hildreth, C. Jessop, D.J. Karmgard, J. Kolb, K. Lannon, W. Luo, S. Lynch, N. Marinelli, D.M. Morse, T. Pearson, R. Ruchti, J. Slaunwhite, N. Valls, M. Wayne, M. Wolf \cmsinstskipThe Ohio State University, Columbus, USA
B. Bylsma, L.S. Durkin, A. Hart, C. Hill, R. Hughes, K. Kotov, T.Y. Ling, D. Puigh, M. Rodenburg, C. Vuosalo, G. Williams, B.L. Winer \cmsinstskipPrinceton University, Princeton, USA
N. Adam, E. Berry, P. Elmer, D. Gerbaudo, V. Halyo, P. Hebda, J. Hegeman, A. Hunt, P. Jindal, D. Lopes Pegna, P. Lujan, D. Marlow, T. Medvedeva, M. Mooney, J. Olsen, P. Piroué, X. Quan, A. Raval, B. Safdi, H. Saka, D. Stickland, C. Tully, J.S. Werner, A. Zuranski \cmsinstskipUniversity of Puerto Rico, Mayaguez, USA
J.G. Acosta, E. Brownson, X.T. Huang, A. Lopez, H. Mendez, S. Oliveros, J.E. Ramirez Vargas, A. Zatserklyaniy \cmsinstskipPurdue University, West Lafayette, USA
E. Alagoz, V.E. Barnes, D. Benedetti, G. Bolla, D. Bortoletto, M. De Mattia, A. Everett, Z. Hu, M. Jones, O. Koybasi, M. Kress, A.T. Laasanen, N. Leonardo, V. Maroussov, P. Merkel, D.H. Miller, N. Neumeister, I. Shipsey, D. Silvers, A. Svyatkovskiy, M. Vidal Marono, H.D. Yoo, J. Zablocki, Y. Zheng \cmsinstskipPurdue University Calumet, Hammond, USA
S. Guragain, N. Parashar \cmsinstskipRice University, Houston, USA
A. Adair, C. Boulahouache, K.M. Ecklund, F.J.M. Geurts, B.P. Padley, R. Redjimi, J. Roberts, J. Zabel \cmsinstskipUniversity of Rochester, Rochester, USA
B. Betchart, A. Bodek, Y.S. Chung, R. Covarelli, P. de Barbaro, R. Demina, Y. Eshaq, A. Garcia-Bellido, P. Goldenzweig, J. Han, A. Harel, D.C. Miner, D. Vishnevskiy, M. Zielinski \cmsinstskipThe Rockefeller University, New York, USA
A. Bhatti, R. Ciesielski, L. Demortier, K. Goulianos, G. Lungu, S. Malik, C. Mesropian \cmsinstskipRutgers, the State University of New Jersey, Piscataway, USA
S. Arora, A. Barker, J.P. Chou, C. Contreras-Campana, E. Contreras-Campana, D. Duggan, D. Ferencek, Y. Gershtein, R. Gray, E. Halkiadakis, D. Hidas, A. Lath, S. Panwalkar, M. Park, R. Patel, V. Rekovic, J. Robles, K. Rose, S. Salur, S. Schnetzer, C. Seitz, S. Somalwar, R. Stone, S. Thomas \cmsinstskipUniversity of Tennessee, Knoxville, USA
G. Cerizza, M. Hollingsworth, S. Spanier, Z.C. Yang, A. York \cmsinstskipTexas A&M University, College Station, USA
R. Eusebi, W. Flanagan, J. Gilmore, T. Kamon\cmsAuthorMark58, V. Khotilovich, R. Montalvo, I. Osipenkov, Y. Pakhotin, A. Perloff, J. Roe, A. Safonov, T. Sakuma, S. Sengupta, I. Suarez, A. Tatarinov, D. Toback \cmsinstskipTexas Tech University, Lubbock, USA
N. Akchurin, J. Damgov, P.R. Dudero, C. Jeong, K. Kovitanggoon, S.W. Lee, T. Libeiro, Y. Roh, I. Volobouev \cmsinstskipVanderbilt University, Nashville, USA
E. Appelt, C. Florez, S. Greene, A. Gurrola, W. Johns, C. Johnston, P. Kurt, C. Maguire, A. Melo, P. Sheldon, B. Snook, S. Tuo, J. Velkovska \cmsinstskipUniversity of Virginia, Charlottesville, USA
M.W. Arenton, M. Balazs, S. Boutle, B. Cox, B. Francis, J. Goodell, R. Hirosky, A. Ledovskoy, C. Lin, C. Neu, J. Wood, R. Yohay \cmsinstskipWayne State University, Detroit, USA
S. Gollapinni, R. Harr, P.E. Karchin, C. Kottachchi Kankanamge Don, P. Lamichhane, A. Sakharov \cmsinstskipUniversity of Wisconsin, Madison, USA
M. Anderson, M. Bachtis, D. Belknap, L. Borrello, D. Carlsmith, M. Cepeda, S. Dasu, L. Gray, K.S. Grogg, M. Grothe, R. Hall-Wilton, M. Herndon, A. Hervé, P. Klabbers, J. Klukas, A. Lanaro, C. Lazaridis, J. Leonard, R. Loveless, A. Mohapatra, I. Ojalvo, F. Palmonari, G.A. Pierro, I. Ross, A. Savin, W.H. Smith, J. Swanson \cmsinstskip†: Deceased
1:  Also at Vienna University of Technology, Vienna, Austria
2:  Also at National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
3:  Also at Universidade Federal do ABC, Santo Andre, Brazil
4:  Also at California Institute of Technology, Pasadena, USA
5:  Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland
6:  Also at Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France
7:  Also at Suez Canal University, Suez, Egypt
8:  Also at Zewail City of Science and Technology, Zewail, Egypt
9:  Also at Cairo University, Cairo, Egypt
10: Also at Fayoum University, El-Fayoum, Egypt
11: Also at British University, Cairo, Egypt
12: Now at Ain Shams University, Cairo, Egypt
13: Also at Soltan Institute for Nuclear Studies, Warsaw, Poland
14: Also at Université de Haute-Alsace, Mulhouse, France
15: Now at Joint Institute for Nuclear Research, Dubna, Russia
16: Also at Moscow State University, Moscow, Russia
17: Also at Brandenburg University of Technology, Cottbus, Germany
18: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary
19: Also at Eötvös Loránd University, Budapest, Hungary
20: Also at Tata Institute of Fundamental Research - HECR, Mumbai, India
21: Also at University of Visva-Bharati, Santiniketan, India
22: Also at Sharif University of Technology, Tehran, Iran
23: Also at Isfahan University of Technology, Isfahan, Iran
24: Also at Shiraz University, Shiraz, Iran
25: Also at Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Teheran, Iran
26: Also at Facoltà Ingegneria Università di Roma, Roma, Italy
27: Also at Università della Basilicata, Potenza, Italy
28: Also at Università degli Studi Guglielmo Marconi, Roma, Italy
29: Also at Università degli studi di Siena, Siena, Italy
30: Also at University of Bucharest, Faculty of Physics, Bucuresti-Magurele, Romania
31: Also at Faculty of Physics of University of Belgrade, Belgrade, Serbia
32: Also at University of Florida, Gainesville, USA
33: Also at University of California, Los Angeles, Los Angeles, USA
34: Also at Scuola Normale e Sezione dell’ INFN, Pisa, Italy
35: Also at INFN Sezione di Roma; Università di Roma ”La Sapienza”, Roma, Italy
36: Also at University of Athens, Athens, Greece
37: Also at Rutherford Appleton Laboratory, Didcot, United Kingdom
38: Also at The University of Kansas, Lawrence, USA
39: Also at Paul Scherrer Institut, Villigen, Switzerland
40: Also at Institute for Theoretical and Experimental Physics, Moscow, Russia
41: Also at Gaziosmanpasa University, Tokat, Turkey
42: Also at Adiyaman University, Adiyaman, Turkey
43: Also at The University of Iowa, Iowa City, USA
44: Also at Mersin University, Mersin, Turkey
45: Also at Ozyegin University, Istanbul, Turkey
46: Also at Kafkas University, Kars, Turkey
47: Also at Suleyman Demirel University, Isparta, Turkey
48: Also at Ege University, Izmir, Turkey
49: Also at School of Physics and Astronomy, University of Southampton, Southampton, United Kingdom
50: Also at INFN Sezione di Perugia; Università di Perugia, Perugia, Italy
51: Also at University of Sydney, Sydney, Australia
52: Also at Utah Valley University, Orem, USA
53: Also at Institute for Nuclear Research, Moscow, Russia
54: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia
55: Also at Argonne National Laboratory, Argonne, USA
56: Also at Erzincan University, Erzincan, Turkey
57: Also at KFKI Research Institute for Particle and Nuclear Physics, Budapest, Hungary
58: Also at Kyungpook National University, Daegu, Korea


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