Search for third-generation scalar leptoquarks in the t-tau channel in proton-proton collisions at sqrt(s) = 8 TeV
EEUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN)
CERN-PH-EP/2015-0632018/08/17
CMS-EXO-14-008
Search for third-generation scalar leptoquarks in the t τ channel in proton-proton collisions at √ s = The CMS Collaboration ∗ Abstract
A search for pair production of third-generation scalar leptoquarks decaying to topquark and τ lepton pairs is presented using proton-proton collision data at a center-of-mass energy of √ s = − . The search is performed usingevents that contain an electron or a muon, a hadronically decaying τ lepton, and twoor more jets. The observations are found to be consistent with the standard modelpredictions. Assuming that all leptoquarks decay to a top quark and a τ lepton, theexistence of pair produced, charge − τ lepton, and may also be ap-plied directly to the pair production of bottom squarks decaying predominantly viathe R-parity violating coupling λ (cid:48) . Published in the Journal of High Energy Physics as doi:10.1007/JHEP07(2015)042. c (cid:13) ∗ See Appendix A for the list of collaboration members a r X i v : . [ h e p - e x ] N ov Leptoquarks (LQ) are hypothetical particles that carry both lepton (L) and baryon (B) quantumnumbers. They appear in theories beyond the standard model (SM), such as grand unifica-tion [1–3], technicolor [4], and compositeness [5, 6] models. A minimal extension of the SMto include all renormalizable gauge invariant interactions, while respecting existing boundsfrom low-energy and precision measurements leads to the effective Buchm ¨uller–R ¨uckl–Wylermodel [7]. In this model, LQs are assumed to couple to one generation of chiral fermions, andto separately conserve L and B quantum numbers. An LQ can be either a scalar (spin 0) or avector (spin 1) particle with a fractional electric charge. A comprehensive list of other possiblequantum number assignments for LQs coupling to SM fermions can be found in Ref. [8].This paper presents the first search for a third-generation scalar LQ (LQ ) decaying into a topquark and a τ lepton. Previous searches at hadron colliders have targeted LQs decaying intoquarks and leptons of the first and second generations [9–11] or the third-generation in theLQ → b ν and LQ → b τ decay channels [12–17]. The presented search for third-generationLQs can also be interpreted in the context of R-parity violating (RPV) supersymmetric mod-els [18] where the supersymmetric partner of the bottom quark (bottom squark) decays into atop quark and a τ lepton via the RPV coupling λ (cid:48) .At hadron colliders, such as the CERN LHC, LQs are mainly pair produced through the quan-tum chromodynamic (QCD) quark-antiquark annihilation and gluon-gluon fusion subproces-ses. There is also a lepton mediated t ( u )-channel contribution that depends on the unknownlepton-quark-LQ Yukawa coupling, but this contribution is suppressed at the LHC for the pro-duction of third-generation LQs as it requires third-generation quarks in the initial state. Hence,the LQ pair production cross section depends only upon the assumed values of the LQ spin andmass, and upon the proton-proton center-of-mass energy. We consider scalar LQs in the massrange up to several hundred GeV. The corresponding next-to-leading-order (NLO) pair pro-duction cross sections and associated uncertainties at √ s = β and 1 − β , respectively. Assuming thatthird-generation scalar LQs with charge − → t τ − and LQ → b ν . In this paper,we initially assume that β = always decays to a t τ pair. The results are thenreinterpreted as a function of the branching fraction with β treated as a free parameter.We consider events with at least one electron or muon and one τ lepton where the τ leptonundergoes a one- or three-prong hadronic decay, τ h → hadron(s) + ν τ . In LQ LQ decays, τ leptons arise directly from LQ decays, as well as from W bosons in the top quark decay chain,whereas electrons and muons are produced only in leptonic decays of W bosons or τ leptons.The major backgrounds come from tt+jets, Drell–Yan(DY)+jets, and W+jets production, wherea significant number of events have jets misidentified as hadronically decaying τ leptons. Thesearch is conducted in two orthogonal selections, labelled as category A and category B. In cat-egory A, a same-sign µτ h pair is required in each event, which suppresses SM backgrounds.Misidentified τ h candidates originating from jets constitute the main background in categoryA. Category B utilizes both e τ h and µτ h pairs with slightly relaxed τ lepton identification cri-teria without imposing a charge requirement on the lepton pair. This yields a higher signalacceptance, but a larger irreducible background from SM processes. In order to keep the twosamples statistically independent, events that satisfy the category A criteria are removed fromthe category B sample. Figure 1 shows a schematic representation of an LQ LQ decay chain LQ LQ t ⌧ ⌧ + tb W + ⌫ ⌧ ⇡ , ⇡ , , ⇡ , , , ⇡ , , + ... ⌫ ` ` + ⌫ ⌧ W bu d ` ⌫ ` ⌧ ` + ` Figure 1: One of the LQ LQ decay chains with both same-sign and opposite-sign (cid:96) τ h pairs.Labels u and d denote up and down type quarks, and (cid:96) denotes an electron or a muon.that can satisfy the requirements for both categories.The signature for this search is chosen to be (cid:96) τ h + X , where (cid:96) denotes an electron or a muon, and X is two or more jets and any additional charged leptons in category A, or three or more jetsand any additional charged leptons in category B. The additional jet requirement in category Bis beneficial in suppressing background events from dominant SM processes with two jets andan opposite-sign (cid:96) τ h pair. The CMS apparatus is a multipurpose particle detector with a superconducting solenoid of 6 minternal diameter, which provides a magnetic field of 3.8 T. Within the volume of the solenoidare a silicon pixel and strip tracker, a lead tungstate crystal electromagnetic calorimeter, and abrass and scintillator hadron calorimeter, each composed of a barrel and two endcap sections.Muons are measured in gas-ionization detectors embedded in the steel flux-return yoke out-side the solenoid. Extensive forward calorimetry complements the coverage provided by thebarrel and endcap detectors. A more detailed description of the CMS detector, together with adefinition of the coordinate system used and the relevant kinematic variables, can be found inRef. [20].The electron, muon, and τ lepton candidates used in this paper are reconstructed using aparticle-flow (PF) event reconstruction technique [21, 22] which reconstructs and identifies sin-gle particles (muons, electrons, charged/neutral hadrons, and photons) using an optimizedcombination of all subdetector information.Muon candidates are reconstructed from a combined track in the muon system and the track-ing system [23]. The hadronically decaying τ lepton candidates are reconstructed via the“hadron-plus-strips” algorithm which combines one or three charged hadrons with up to twoneutral pions that are reconstructed from PF candidates combining tracker and calorimeter in-formation [24]. Electron candidates are obtained by reconstructing trajectories from hits in thetracker layers and energy depositions in the electromagnetic calorimeter with a Gaussian sumfilter [25].Jets are reconstructed by using the anti- k T algorithm [22, 26, 27] to cluster PF candidates with adistance parameter of ∆ R = ∆ R = √ ( ∆ η ) + ( ∆ φ ) , η denotes the pseudorapidityand φ denotes the azimuthal angle in radians). The missing transverse momentum (cid:126) p missT iscalculated as a negative vectorial sum of the transverse momenta of all the PF candidates. Themissing transverse energy E missT is defined as the magnitude of the (cid:126) p missT vector. Jet energycorrections are applied to all jets and are also propagated to the calculation of E missT [28]. The collisions are selected using a two-tiered trigger system, composed of a hardware basedlevel-1 trigger and a software based high-level trigger (HLT) [29] running on a computing farm.The following quantities are constructed using the physics objects described earlier: • S T is the scalar p T sum of all objects in the event, including muons, hadronicallydecaying τ leptons, electrons, jets, and E missT . • M T ( (cid:96) , (cid:126) p missT ) is the transverse mass, (cid:113) p (cid:96) T E missT ( − cos ( ∆ φ ( (cid:126) p missT , (cid:96) ))) , reconstructedfrom the given lepton and the (cid:126) p missT in the event where ∆ φ ( (cid:126) p missT , (cid:96) ) is the differencein the azimuthal angle between the directions of the missing transverse momentumand the lepton momentum. • (cid:102) | η | is the pseudorapidity defined as (cid:102) | η | = − ln tan ( ¯ θ /2 ) , where ¯ θ is the averageabsolute polar angle of all electrons, muons, and hadronically decaying τ leptons inan event as measured from the beam-axis in the lab frame, and is used as a measureof the event centrality. This analysis uses data collected with the CMS detector at the LHC during proton-proton (pp)collisions at √ s = − in category A, andusing isolated single-muon or single-electron data corresponding to an integrated luminosityof 19.7 fb − in category B. The muon triggers require a muon candidate to have p T >
24 GeVand | η | < p T >
27 GeVand | η | < PYTHIA generator (v6.426) [30]. Singletop quark and top quark pair production have been simulated with
POWHEG (v1.0) [31–34].For the W+jets background, DY+jets processes, and tt production in association with W or Zbosons, M AD G RAPH (v5.1) has been used [35]. Diboson and QCD multijet processes as well asprocesses involving Higgs bosons have been generated with
PYTHIA , other SM backgroundshave been simulated with M AD G RAPH . The parton shower and hadronization in samples gen-erated with
POWHEG or M AD G RAPH has been performed with
PYTHIA . In case of M AD G RAPH ,the matching to
PYTHIA has been done with the MLM scheme [36]. In all of the generated sam-ples, τ lepton decays were simulated via TAUOLA [37] and the response of the CMS detectorhas been simulated with G
EANT
POWHEG samples are produced with the CT10 [39]parton distribution function (PDF), all other samples have been generated using CTEQ6L1 [40]PDF set. The Monte Carlo (MC) simulated events are re-weighted to account for differencesin trigger and lepton reconstruction efficiencies, pileup modeling, and jet/missing transverseenergy response of the detector. The simulated events are normalized using next-to-next-to-leading-order (NNLO) (W+jets, DY+jets [41], tt+jets [42], WH, ZH [43]), approximate NNLO (t,tW [44]), NLO (diboson [45], ttZ [46], ttW [46, 47], ttH [48, 49], triboson [50]), or leading-order(W ± W ± qq, ttWW, W γ ∗ , QCD multijet [30, 35]) cross sections at √ s = p T spectrum of top quarks [51] and theleading jet [52], respectively. Re-weighting factors, parametrized as functions of the respective p T distributions, are applied to the simulated events to correct for these discrepancies. The Table 1: Summary of the search strategies in event categories A and B.
Category A Category BLepton selection Same-sign µτ h pair µτ h or e τ h pair(category A events are removed)Jet selection At least two jets At least three jets E missT requirement No E missT requirement E missT >
50 GeV S T and τ lepton p T Optimized for each LQ S T > p τ T >
20 GeVrequirements mass hypothesisBackground estimation Main component containing Estimated via simulation, correctionsmisidentified muons & τ leptons applied for τ lepton misidentificationestimated using data events rate and top quark and W p T distributionsSearch regions 2 search regions binned in (cid:102) | η | τ lepton p T regionsfor µτ h and e τ h channels correction factors for tt+jets [51] range up to 30% whereas the correction factors for the W+jetssamples vary between 8% and 12%. A summary of the search regions, selection criteria, and the methods used to determine back-ground contributions for categories A and B is given in Table 1.
In category A, two selections, denoted as loose and tight, are defined for the muon and τ leptoncandidates, which differ only in the thresholds of the isolation requirements. The tight selec-tions are applied to define the signal region, and the loose selections are used in the estimationof backgrounds as defined in Section 5.1.Muon candidates are required to have p T >
25 GeV and | η | < p T sum of allPF candidates in a cone of radius ∆ R = p T . The muon kinematic and isolation thresholds are chosen to match the trigger requirementsused in selecting the events.Hadronically decaying τ lepton candidates are required to satisfy p T >
20 GeV and | η | < τ lepton selection, the scalar p T sum of charged hadron and photon PF candidateswith p T > ∆ R = τ lepton candidate is required tobe less than 3 GeV. For the tight τ lepton selection, a more restrictive isolation requirement isapplied with a cone of radius ∆ R = τ h candi-dates are required to satisfy a requirement that suppresses the misidentification of electronsand muons as hadronically decaying τ leptons [24].Electron candidates are required to have p T >
15 GeV and | η | < p T sum of all PF candidates in a cone of radius ∆ R = p T , is required to be less than 15%.All muon, electron, and τ h candidates are required to be separated by ∆ R > τ lepton candidates and the nearestjet to which they do not contribute is required to be ∆ R ( µ , j ) min > ∆ R ( τ , j ) min > .2 Event selection in category B respectively. This requirement is imposed in order to reduce the impact of QCD jet activity onthe respective isolation cones.Jet candidates are required to have p T >
40 GeV, | η | <
3. Jets overlapping with the electron,muon, and τ h candidates within a cone of ∆ R = µτ h pair, chosen among the muon and τ h leptoncandidates satisfying the loose selection criteria. If the event contains more than one µτ h pair,the same-sign pair with the largest scalar sum p T is selected. The selected µτ h pair is thenrequired to satisfy the tight selection criteria. Events failing the tight selection criteria on oneor both leptons are utilized in the estimation of backgrounds described in Section 5.1.For the signal selection, same-sign µτ h events are required to have S T >
400 GeV and twoor more jets. Events containing an opposite-sign dimuon pair with an invariant mass within10% of the Z boson mass are vetoed. In order to exploit a feature of the signal model thatproduces the LQ pair dominantly in the central region, the search is split into two channelswith (cid:102) | η | < (cid:102) | η | ≥ S T , p τ T ) plane foreach LQ mass hypothesis in the range of 200–800 GeV. The p τ T requirement is only appliedto the τ lepton candidate that is a part of the selected same-sign µτ h pair. The optimization isaccomplished by maximizing the figure of merit given in Eq. (1) [53]: χ ( p τ T , S T ) = ε ( p τ T , S T ) + (cid:113) B ( p τ T , S T ) (1)where ε is the signal efficiency and B is the number of background events. The ( S T , p τ T ) thresh-olds have been optimized in the central channel and applied identically in the forward channel.These optimized selections and the corresponding efficiencies as a function of the LQ mass arepresented later, in Section 6.A signal-depleted selection of events with a same-sign µτ h pair, created by vetoing events withmore than one jet, is used to check the performance and normalization of the simulated back-ground samples. In order to reduce the QCD multijet background contribution, an additionalrequirement of M T ( µ , E missT ) >
40 GeV is imposed using the muon candidate in the selectedsame-sign µτ h pair. Figure 2 illustrates the agreement between data and simulation in the (cid:102) | η | and S T distributions, which is found to be within 20%. In category B, muon candidates are required to have p T >
30 GeV and | η | < τ leptons must satisfy p T >
20 GeV and | η | < τ h candidatesa medium isolation requirement is used, where the scalar p T sum of PF candidates must notexceed 1 GeV in a cone of radius ∆ R = τ h candidates must satisfy therequirement discriminating against misreconstructed electrons and muons.Electron candidates are required to have p T >
35 GeV and | η | < τ h channel.Jets are required to have p T >
30 GeV, | η | < τ h candidateswithin a cone of ∆ R = τ leptons that overlap with a muon, andelectrons that overlap with a jet within a cone of ∆ R = Each event is required to have at least one electron or muon and one τ h candidate. Eventscontaining muons are vetoed in the e τ h channel. Events satisfying the category A selectioncriteria are also vetoed, thus in the case of the µτ h selection, category B mostly consists ofevents with opposite-sign µτ h pairs.In addition, events are required to have S T > E missT >
50 GeV, and at least threejets, where the leading and subleading jets further satisfy p T >
100 and 50 GeV, respectively.The analysis in category B is performed in four search regions defined as a function of thetransverse momentum of the leading τ h candidate: 20 < p τ T <
60 GeV, 60 < p τ T <
120 GeV,120 < p τ T <
200 GeV, and p τ T >
200 GeV. Since events with e τ h and µτ h pairs are separated, thisselection leads to eight search regions. The two low- p τ T regions are mainly used to constrain theSM background processes, whereas the signal is expected to populate the two high- p τ T regions.The selections on S T , the momenta of the three jets, and E missT have been optimized with respectto the expected limits on the signal cross section obtained in the statistical evaluation of thesearch regions as described in Section 6.A signal-depleted selection is used to check the performance of the simulated background sam-ples in category B. In this selection, events with (cid:96) τ h pairs are required to have E missT <
50 GeVand at least two jets with p T >
50 GeV, | η | < p τ T distribu-tions. In the e τ h channel, a small excess in the p T distribution is observed around 150 GeV.As the other kinematic distributions in the signal-depleted region show no other significantdeviations, the excess is assumed to be a statistical fluctuation. E v en t s pe r b i n
10 DataW+jetsDY+jets+jetsttOther backgrounds (8 TeV) -1 CMS
Category A | η∼ |0 0.5 1 1.5 2 D a t a / M C E v en t s pe r G e V
10 DataW+jetsDY+jets+jetsttOther backgrounds (8 TeV) -1 CMS
Category A [GeV] T S0 100 200 300 400 500 600 700 800 D a t a / M C Figure 2: Comparison between data and simulation in the (cid:102) | η | (left) and S T (right) distributionsusing the signal-depleted selection of events in category A with a same-sign µτ h pair. Otherbackgrounds refer to contributions predominantly from processes such as diboson and singletop quark production, as well as QCD multijet and other rare SM processes detailed in Sec-tion 3. The hatched regions in the distributions and the shaded bands in the Data/MC ratioplots represent the statistical uncertainties in the expectations. The data-simulation agreementis observed to be within 20%, and is assigned as the normalization systematic uncertainty forthe tt+jets, DY+jets and diboson contributions in the signal region. E v en t s pe r G e V
10 Data+jetsttW+jetsDY+jetsOther backgrounds (8 TeV) -1 CMS h τµ Category B: [GeV] τ T leading p0 50 100 150 200 250 300 D a t a / M C E v en t s pe r G e V
10 Data+jetsttW+jetsDY+jetsOther backgrounds (8 TeV) -1 CMS h τ e Category B: [GeV] τ T leading p0 50 100 150 200 250 300 350 D a t a / M C Figure 3: Comparison between data and simulation in the leading τ lepton p T distributionsusing the signal-depleted selection of events in category B in the µτ h channel (left) and in thee τ h channel (right). Other backgrounds refer to contributions predominantly from processessuch as diboson and single top quark production, but also include QCD multijet and rare SMprocesses detailed in Section 3. The hatched regions in the distributions and the shaded bandsin the Data/MC ratio plots represent the statistical uncertainties in the expectations. For this analysis, prompt leptons are defined to be those that come from the decays of Wbosons, Z bosons or τ leptons, and are usually well isolated. Leptons originating from semilep-tonic heavy-flavor decays within jets and jets misreconstructed as leptons are both labelled asmisidentified leptons, and generally are not isolated. In category A, the expected same-signbackground events are mostly due to misidentified leptons, while category B has significantadditional prompt-prompt contributions. In accordance with the expected background com-positions, data events are used to estimate the dominant misidentified lepton backgrounds incategory A, eliminating the need to evaluate the simulation based systematic uncertainties,whereas the prompt-prompt backgrounds in category B require the consideration of these un-certainties. Simulated samples corrected for τ lepton misidentification rates are used for theestimation of the backgrounds in category B. The same-sign dilepton requirement yields a background which mainly consists of events thatcontain misidentified leptons (especially jets misidentified as τ leptons). These events comefrom semileptonic tt+jets and W+jets processes in approximately equal proportions. Smallerbackground contributions result from SM processes with genuine same-sign dileptons, suchas diboson, ttW, ttZ, and W ± W ± qq events, and opposite-sign dilepton events in which the τ h charge has been misidentified, such as DY+jets and fully leptonic tt+jets events. Events withmisidentified leptons contribute up to 90% of the total background, depending on the set of S T and τ lepton p T requirements, and are especially dominant in selections for M LQ ≤
400 GeV.
Background contributions due to misidentified leptons are estimated using the observed datavia a “matrix method” [54]. For a given set of selection requirements, four combinations aredefined based on the selection quality of the selected same-sign µτ h pair. Events in whichboth leptons satisfy the tight selection requirements are classified as TT events, whereas thosewith both leptons failing the tight selection while satisfying the loose selection requirementsare classified as LL events. Similarly, events with only the muon or the τ h candidate satisfyingthe tight selection and with the other lepton satisfying the loose selection but failing the tightselection requirements are labeled as TL or LT events, respectively, where the muon is denotedfirst in the labeling.The probabilities with which prompt ( p ) and misidentified ( m ) muon and τ h candidates pass atight selection, given that they satisfy a loose selection, are measured as a function of the lepton p T in regions of S T , lepton | η | , and ∆ R ( µ , j ) min or ∆ R ( τ , j ) min . The TT events constitute thesearch region, whereas TL, LT, and LL events, together with the prompt and misidentificationprobabilities, are used to calculate the misidentified lepton contributions to the signal region, N misIDTT , as given in Eqs. (2) and (3). N MM N MP N PM N PP = ( p µ − m µ )( p τ − m τ ) p µ · p τ − p µ · (cid:99) p τ − (cid:99) p µ · p τ (cid:99) p µ · (cid:99) p τ − p µ · m τ p µ · (cid:99) m τ (cid:99) p µ · m τ − (cid:99) p µ · (cid:99) m τ − m µ · p τ m µ · (cid:99) p τ (cid:99) m µ · p τ − (cid:99) m µ · (cid:99) p τ m µ · m τ − m µ · (cid:99) m τ − (cid:99) m µ · m τ (cid:99) m µ · (cid:99) m τ N LL N LT N TL N TT , (2) N misIDTT = m µ m τ N MM + m µ p τ N MP + p µ m τ N PM . (3) N denotes the number of events in a given combination, and MM, MP, PM, and PP labels de-note the double-misidentified, muon misidentified, τ h misidentified, and double-prompt com-binations, respectively. The complementary prompt probability is given as (cid:98) p = − p , and thecomplementary misidentification probability is given as (cid:98) m = − m .Muon and τ lepton prompt probabilities are measured in DY+jets enhanced data regions withZ → µµ and Z → ττ → µτ h decays, respectively, and in simulated tt+jets, W+jets and LQ events. For the τ lepton misidentification probability measurements, a W ( → µν ) +jets enricheddata set with additional τ h candidates is used. A QCD multijet enhanced data set with a singlemuon candidate is used for the muon misidentification probability measurements. In simu-lated samples, the τ lepton misidentification probability measurement is conducted in W+jets,tt+jets, and LQ samples, while the muon misidentification probability measurement is madein QCD multijet, tt+jets, and LQ samples.The individual prompt and misidentification probability measurements conducted using sim-ulated samples are combined into a single value for each of the p and m bins. For each of these,an average value and an associated uncertainty is calculated to account for the process de-pendent variations. These simulation based values are then combined with correction factorsderived from the p and m measurements in data, to account for any bias in the simulated detec-tor geometry and response, providing the values used in Eqs. (2) and (3). The resultant muonprompt probabilities vary from ( ± ) % to ( ± ) % for low and high p T muons, whereas τ lepton prompt probabilities are around ( ± ) %. The muon and τ lepton misidentificationprobabilities are measured to be about ( ± ) % and ( ± ) %, respectively.The matrix method yields consistent results for the misidentification backgrounds when ap-plied to a signal-depleted selection of events in data and to simulated events in the signal .2 Backgrounds in category B region. The expected yields are in agreement with the observations within 1.5 standard devia-tions in both selections. The background contributions due to lepton charge misidentification and irreducible processeswith same-sign µτ h pairs are estimated directly from the simulated samples. These prompt-prompt contributions are calculated by requiring a match ( ∆ R < τ h candidates,and these backgrounds contribute to 2–3% of the total expected backgrounds in selections for M LQ ≤
400 GeV, whereas are negligible in those for higher LQ masses. In category B, major background processes are tt+jets, W+jets, and DY+jets events. Smallercontributions come from single top quark, diboson, ttZ, and QCD multijet events. Contribu-tions from prompt-prompt (cid:96) τ h pairs are mainly expected in fully leptonic tt+jets events, as wellas DY+jets events with Z → ττ → (cid:96) τ h decays and diboson events. In all other processes,the τ h candidates are expected to originate from misidentified jets. The misidentified electronand muon contributions have been found to be negligible after applying isolation and E missT requirements. The background estimation in category B is obtained from simulated sampleswith various corrections applied to account for differences between data and simulation in thereconstruction and identification of misidentified τ lepton candidates.The τ lepton misidentification rate is defined as the probability for a misidentified τ lepton can-didate originating from a jet to satisfy the final τ lepton identification criteria used in the analy-sis. The corresponding correction factor for the simulation is defined as the ratio of the data andthe simulation-based rates. The misidentification rates in data and simulation are measured inW ( → (cid:96) ν ) +jets enriched events, containing at least one τ lepton candidate. The τ lepton can-didate is used as a misidentified probe, and the results are parametrized as a function of the τ lepton p T . Additional parametrizations, such as S T , jet multiplicity, and ∆ R ( τ , j ) min , reveal nofurther deviations between the data and simulation. Thus a one-dimensional parametrizationas a function of the τ lepton p T is used to describe any discrepancy between data and simu-lation. A small discrepancy is observed in the distribution of scale factors as a function of the τ lepton η for | η | > τ lepton scalefactors for misidentified τ leptons in this η region.Measurements based on data are corrected by subtracting the small contributions due to prompt τ leptons, muons, and electrons which are misidentified as τ lepton candidates using the pre-dictions from the simulated samples. The systematic uncertainties in the correction factorsare estimated by varying the cross sections of the dominant simulated processes within theiruncertainties [55].The resulting correction factors on the τ lepton misidentification rate are found to be in therange of 0.6–1.1 for the four τ lepton p T regions. These weights are applied to each misidenti-fied τ lepton candidate in all simulated background processes.A jet originating from gluon emission has a smaller probability of being misidentified as a τ h candidate than those originating from quarks. Quarks tend to produce incorrectly assigned τ lepton candidates with a like-sign charge. Therefore, an additional systematic uncertaintyis assigned to the correction factors based on the flavor composition of jets misidentified as τ leptons. To determine this uncertainty, the measurement of the τ lepton misidentification rate is repeated for each of the charge combinations of the (cid:96) τ h pair, τ ± h (cid:96) ± and τ ± h (cid:96) ∓ . Because of thedifferent production modes of W + and W − bosons at the LHC, the four charge combinationshave different quark and gluon compositions. An estimate of the maximally allowed variancein the probability of each quark or gluon type to be misidentified as a τ lepton is obtainedvia the comparison of the misidentification rate measurements in the four channels. The un-certainties in the misidentification rates are scaled according to the different expected flavorcompositions in the signal and W ( → (cid:96) ν ) +jets enriched regions used for the misidentificationrate measurements. In category A, the backgrounds due to misidentified leptons are derived from data and theassociated systematic uncertainties are calculated by propagating the uncertainties in the muonand τ lepton prompt and misidentification probability measurements. The uncertainties in thebackground rate of misidentified leptons lie in the range of 21–28% in the central channel and21–36% in the forward channel.In category B, the uncertainties in the correction factors on the misidentification rate of τ lep-tons vary from 23–38% for the lower three τ lepton p T regions and up to 58–82% for the highest p T region in the µτ h and e τ h channels. These uncertainties are propagated to the estimate of thebackground of misidentified hadronically decaying τ leptons by varying the correction factorsapplied to the simulation within their uncertainties.Since both the signal efficiencies and the prompt-prompt contributions to the background incategory A and all the signal and background estimates in category B are determined usingsimulated events, the following sources of systematic uncertainty are considered.Normalization uncertainties of 20% are applied for tt+jets, DY+jets and diboson processes incategory A as observed in the signal-depleted region presented in Fig. 2. An uncertainty of30% is applied for other rare SM process as motivated by the theoretical uncertainties in theNLO cross sections for processes such as ttW, ttZ [46, 47], and triboson [50] production. Forcategory B, these uncertainties in the MC normalization vary in a range between 15% and 100%according to previous measurements [55]. The CMS luminosity used in the normalization ofsignal and MC samples has an uncertainty of 2.6% [56].In order to account for uncertainties in the efficiency of τ lepton identification, an uncertaintyof 6% is applied for each prompt τ lepton found in the event. The uncertainty in the τ leptonenergy is taken into account by varying the energy of all τ leptons by ± τ leptons in simulated samples are estimated bychanging the resolution by ± ≤ τ h channel of category B. These uncertainties are p T - and η -dependent and arefound to be 0.3% for electrons in the central detector region with p T <
50 GeV and up to 25%for electrons with p T >
500 GeV.Uncertainties in the jet energy resolution [27] are taken into account by changing the correctionfactors within their uncertainties. These correction factors lie between 1.05 and 1.29 dependingon jet η , with corresponding uncertainties varying from 5% to 16%. The p T - and η -dependentscale factors for the jet energy scale [27] are similarly varied by one standard deviation to obtain .3 Systematic uncertainties the corresponding uncertainties in simulated samples. This corresponds to a 1–3% variation ofthe scale factors.The energy scale and resolution uncertainties in τ lepton, muon, electron, and jet candidatesare also propagated in the calculation of E missT and S T .The uncertainty in the pileup re-weighting of simulated samples is estimated by varying thetotal inelastic cross section [58] by 5%. Signal samples are produced with the CTEQ6L1 PDF setand the associated PDF uncertainties in the signal acceptance are estimated using the PDF un-certainty prescription for LHC [59–61]. In category B, the PDF uncertainties are also calculatedfor the background processes estimated using simulations.Additional uncertainties in major SM processes estimated from simulations are considered incategory B. Uncertainties in the factorization and normalization scales, µ r and µ f , respectively,on tt+jets and W+jets events are calculated by changing the corresponding scales by a factorof 2 or 0.5. The effect of an uncertainty in the jet-parton matching threshold in the simulationof W+jets processes is evaluated by varying it within a factor of 2. The uncertainty in the topquark p T re-weighting procedure is estimated by doubling and removing the correction factors.Table 2 shows a summary of the systematic uncertainties for categories A and B.Table 2: Systematic uncertainty sources and their effects on background ( B ) and signal ( S ) es-timates. Uncertainties affecting the signal yields in both categories and the background yieldsin category A are calculated using the selection criteria for the M LQ =
550 GeV hypothesis.In category A, the uncertainties are reported for central/forward channels separately, whereappropriate. In category B, all uncertainties are averaged over the four p τ T search bins. All val-ues are symmetric except for the PDF uncertainty in the signal acceptance in category A, andthe tt factorization and normalization scale uncertainty in category B. The τ misidentificationrate uncertainties considered in category B are included in the matrix method uncertainty incategory A. All uncertainties in the background estimates are scaled according to their relativecontributions to the total expected background. Category A Category B µτ h ch. e τ h ch.Systematic uncertainty Magnitude (%) B (%) S (%) B (%) S (%) B (%) S (%)Integrated luminosity 2.6 0.4/1.2 2.6 2.6 2.6 2.6 2.6Electron reco/ID/iso & trigger p T , η dependent — — — — 1.4 2.2Muon reco/ID/iso & trigger 1.1 0.1/0.5 1.1 0.9 0.9 — — τ lepton reco/ID/iso 6.0 0.8/2.8 6.0 1.5 3.0 0.6 3.1Muon momentum scale & resolution p T dependent 0.1/0.3 0.4 — — — — τ lepton energy scale 3.0 1.2/4.1 2.0 2.3 2.7 0.6 1.5 τ lepton energy resolution 10.0 0.2/0.8 0.9 1.2 1.3 0.2 0.1Jet energy scale p T , η dependent 0.9/3.2 1.9 4.2 1.9 5.6 2.7Jet energy resolution η dependent 0.4/1.2 1.0 0.8 0.3 1.6 0.8Pileup 5.0 0.1/1.2 1.0/2.5 0.8 0.3 0.9 0.5PDF (on acceptance) — — + − (cid:14) + − — 0.7 — 0.9PDF (on background) — — — 8.7 — 8.3 —Matrix method — 23.1/15.3 — — — — —Jet → τ misidentification rate p T dependent — — 8.2 1.0 10.9 0.8e → τ misidentification rate η dependent — — 0.1 0.1 0.1 0.1tt factorization/renormalization + − — — + − — + − —Top quark p T re-weighting p T dependent — — 0.1 — 0.1 —W+jets factorization/renormalization + − — — 4.3 — 0.3 —W+jets matching threshold + − — — 1.3 — 2.5 — The search results for category A (B) are presented in Table 3 (4 and 5). Figures 4 and 5 showthe comparison of data and the predicted backgrounds as a function of S T , τ lepton p T , andjet multiplicity parameters. The dashed curves show the expectation for LQ signals. For thecomparison of expected and observed number of events in Tables 3–5 and Figs. 4–5, Z-scoresare used. These are computed taking into account the total uncertainty in the mean number ofexpected events. A unit Z-score, | Z | =
1, refers to a two-tailed 1-standard deviation quantile( ∼ − τ lepton and muon identification and isolation efficiencies, τ lepton energy scale and resolution, PDFs, and integrated luminosity.The observed and expected exclusion limits as a function of the LQ mass are shown in Fig. 6.Assuming a unit branching fraction of LQ decays to top quark and τ lepton pairs, pair pro-duction of third-generation LQs is excluded for masses up to 685 GeV with an expected limitof 695 GeV. The exclusion limits worsen as the LQ mass approaches the mass of the top quarkbecause the LQ decay products become softer. At M LQ =
200 GeV, more than 90% of τ lep-tons originating from LQ decays have p T <
60 GeV, which causes a decrease both in the signalselection efficiency and the discriminating performance of the τ lepton p T spectrum. Therefore,no exclusion limits are quoted for masses below 200 GeV.Branching fraction dependent exclusion limits are presented in Fig. 6 (lower right), where limitson the complementary LQ → b ν ( β =
0) decay channel are also included. The results for β = β = β range. If upper limits on β are to be used to constrain the lepton-quark-LQ Yukawa couplings, λ b ν and λ t τ , kinematic suppression factors that favor b ν decayover the t τ have to be considered as well as the relative strengths of the two Yukawa couplings[12, 13].Additionally, the results presented here for the third-generation scalar LQs are directly reinter-preted in the context of pair produced bottom squarks decaying into top quark and τ leptonpairs. Thus, pair production of bottom squarks where the decay mode is dominated by theRPV coupling λ (cid:48) is also excluded up to a bottom squark mass of 685 GeV. Table 3: Category A search results in the signal region for several LQ mass hypotheses. The τ lepton p T and S T columns represent the optimized thresholds defined in Section 4.1. Thecorresponding expected number of prompt-prompt and total background events, as well asthe observed number of data events are listed as N PPBkg , total N ExpBkg , and N Obs . The statisticaland systematic uncertainties quoted in the expected number of background events are com-binations of misidentified lepton and prompt-prompt components. The (cid:101) LQ is the expectedsignal efficiency at a given LQ mass with respect to the total number of expected LQ signalevents at √ s = µτ h pair of any charge combination. No expected signal efficiencyfor M LQ =
200 GeV is reported in the forward channel since the associated yield in the signalsample was measured to be zero. M LQ p τ T S T N PPBkg
Total N ExpBkg N Obs
Z-score N ExpLQ (cid:101) LQ (GeV) (GeV) (GeV) ± (stat) ± (stat) ± (syst) ± (stat) (%)Central channel: (cid:102) | η | < ± ± ±
25 105 − ±
21 0.04250 35 410 8.5 ± ± ±
25 105 − ±
24 0.58300 50 470 4.2 ± ± ± − ±
11 0.98350 50 490 4.0 ± ± ± − ± ± ± ± − ± ± ± ± − ± ± ± ± + ± ± ± ± + ± ± ± ± + ± ± ± ± + ± ± ± ± + ± ± ± ± + ± ± ± ± + ± (cid:102) | η | ≥ ± ± ±
15 87 + ± ± ±
15 87 + ±
11 0.11300 50 470 1.8 ± ± ± + ± ± ± ± + ± ± ± ± − ± ± ± ± − ± ± ± ± ± ± ± ± + ± ± ± ± + ± ± ± ± + ± ± ± ± − ± ± ± ± − ± ± ± ± − ± Table 4: Category B search results for the four p τ T search regions of the µτ h channel. All expectedvalues for background and signal processes (LQ masses indicated in parentheses) are reportedwith the corresponding statistical and systematic uncertainties. The expected signal efficiency (cid:101) LQ at a given LQ mass is determined with respect to the total number of expected LQ signalevents at √ s = µτ h pair of any charge combination, and (cid:101) LQ is reported separatelyfor opposite-sign (OS) and same-sign (SS) µτ h events. Process p τ T <
60 GeV 60 < p τ T <
120 GeV 120 < p τ T <
200 GeV p τ T >
200 GeV (cid:101) LQ (%)OS SSLQ (200 GeV) 21 ± + − ± ± ± ± ± ± (250 GeV) 31.0 ± + − ± + − ± ± ± ± (300 GeV) 33.1 ± + − ± + − ± + − ± + − (350 GeV) 18.1 ± + − ± + − ± + − ± + − (400 GeV) 13.9 ± + − ± + − ± + − ± + − (450 GeV) 10.1 ± + − ± + − ± + − ± + − (500 GeV) 5.2 ± + − ± ± ± + − ± + − (550 GeV) 3.2 ± + − ± + − ± + − ± ± (600 GeV) 2.0 ± + − ± ± ± ± ± ± (650 GeV) 1.3 ± + − ± + − ± ± ± + − (700 GeV) 0.7 ± ± ± ± ± ± ± + − (750 GeV) 0.4 ± ± ± ± ± ± ± ± (800 GeV) 0.2 ± ± ± ± ± ± ± ± ± + − ± + − ± + − ± + − W+jets 7.4 ± + − ± ± ± ± ± ± ± ± ± + − ± ± ± ± ± + − ± + − ± ± ± + − Total N ExpBkg ± + − ± + − ± ± ± + − N Obs
44 15 1 0Z-score − + + − Table 5: Category B search results for the four p τ T search regions of the e τ h channel. All expectedvalues for background and signal processes (LQ masses indicated in parentheses) are reportedwith the corresponding statistical and systematic uncertainties. The expected signal efficiency (cid:101) LQ at a given LQ mass is determined with respect to the total number of expected LQ signalevents at √ s = τ h pair of any charge combination. Process p τ T <
60 GeV 60 < p τ T <
120 GeV 120 < p τ T <
200 GeV p τ T >
200 GeV (cid:101) LQ LQ (200 GeV) 32 ± + − ± ± ± ± ± ± (250 GeV) 33.3 ± + − ± + − ± ± ± ± (300 GeV) 31.9 ± + − ± + − ± + − ± + − (350 GeV) 19.6 ± + − ± + − ± + − ± ± (400 GeV) 12.7 ± + − ± + − ± + − ± + − (450 GeV) 7.8 ± + − ± + − ± + − ± + − (500 GeV) 4.8 ± + − ± + − ± ± ± + − (550 GeV) 3.3 ± + − ± ± ± ± ± ± (600 GeV) 1.9 ± + − ± ± ± ± ± ± (650 GeV) 1.2 ± + − ± ± ± ± ± + − (700 GeV) 0.7 ± + − ± ± ± ± ± ± (750 GeV) 0.4 ± ± ± ± ± ± ± + − (800 GeV) 0.2 ± ± ± ± ± ± ± ± ± ± ± + − ± ± ± + − W+jets 8.5 ± + − ± + − ± ± ± ± ± + − ± + − ± ± ± ± ± + − ± + − ± ± ± ± N ExpBkg ± + − ± + − ± ± ± + − N Obs
53 5 4 1Z-score + − + +
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200 GeV (all other optimized selection criteria yield events that are a subset ofthis selection). The rightmost bin of each distribution includes overflow and no statisticallysignificant excess is observed in the suppressed bins. The systematic uncertainty for each bin ofthese distributions is determined independently. Shaded regions in the histograms representthe total statistical and systematic uncertainty in the background expectation. The Z-scoredistribution is provided at the bottom of each plot.
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Number of jets2 4 6 8 10 12 14 Z - sc o r e -4-2024 Figure 5: The leading τ lepton p T , S T , and jet multiplicity distributions in the signal regionof category B for µτ h (left column) and e τ h (right column) channels. The rightmost bin ofeach distribution includes overflow and no statistically significant excess is observed in thesuppressed bins. Shaded regions in the histograms represent the total statistical and systematicuncertainty in the background expectation. The Z-score distribution is provided at the bottomof each plot. The four regions of the τ lepton p T correspond to the four search regions. mass [GeV] LQ
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200 300 400 500 600 700 800 ) t t fi L Q ( b Combination: n b fi LQ and t t fi LQ Observed limitExpected limitExpected 68% (8 TeV) -1 CMS
Figure 6: The expected and observed exclusion limits at 95% CL on the LQ pair productioncross section times β in category A (upper left), category B (upper right) and the combinationof the two categories (lower left). The theoretical uncertainty in the LQ pair production crosssection includes the PDF and renormalization/factorization scale uncertainties as prescribed inRef. [19]. The expected and observed limits on the LQ branching fraction β as a function of theLQ mass (lower right). The total excluded region (shaded) is obtained by including the resultsin Ref. [17], reinterpreted for the LQ → b ν scenario.9
Figure 6: The expected and observed exclusion limits at 95% CL on the LQ pair productioncross section times β in category A (upper left), category B (upper right) and the combinationof the two categories (lower left). The theoretical uncertainty in the LQ pair production crosssection includes the PDF and renormalization/factorization scale uncertainties as prescribed inRef. [19]. The expected and observed limits on the LQ branching fraction β as a function of theLQ mass (lower right). The total excluded region (shaded) is obtained by including the resultsin Ref. [17], reinterpreted for the LQ → b ν scenario.9 A search for pair produced, charge − τ lepton pairs has been conducted in the (cid:96) τ h channel with two or more jets, usinga proton-proton collisions data sample collected with the CMS detector at √ s = − . No statistically significant excess is observedover the SM background expectations. Assuming that all leptoquarks decay to a top quark anda τ lepton, the pair production of charge − λ (cid:48) . Acknowledgments
We congratulate our colleagues in the CERN accelerator departments for the excellent perfor-mance of the LHC and thank the technical and administrative staffs at CERN and at other CMSinstitutes for their contributions to the success of the CMS effort. In addition, we gratefullyacknowledge the computing centers and personnel of the Worldwide LHC Computing Gridfor delivering so effectively the computing infrastructure essential to our analyses. Finally, weacknowledge the enduring support for the construction and operation of the LHC and the CMSdetector provided by the following funding agencies: BMWFW and FWF (Austria); FNRS andFWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS,MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus);MoER, ERC IUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA andCNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NIH(Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Re-public of Korea); LAS (Lithuania); MOE and UM (Malaysia); CINVESTAV, CONACYT, SEP,and UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland);FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS and RFBR (Russia); MESTD (Serbia);SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter,IPST, STAR and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine);STFC (United Kingdom); DOE and NSF (USA).Individuals have received support from the Marie-Curie program and the European ResearchCouncil and EPLANET (European Union); the Leventis Foundation; the A. P. Sloan Founda-tion; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; theFonds pour la Formation `a la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium);the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministryof Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Science and In-dustrial Research, India; the HOMING PLUS program of the Foundation for Polish Science,cofinanced from European Union, Regional Development Fund; the Compagnia di San Paolo(Torino); the Consorzio per la Fisica (Trieste); MIUR project 20108T4XTM (Italy); the Thalisand Aristeia programs cofinanced by EU-ESF and the Greek NSRF; and the National PrioritiesResearch Program by Qatar National Research Fund.
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Yerevan Physics Institute, Yerevan, Armenia
V. Khachatryan, A.M. Sirunyan, A. Tumasyan
Institut f ¨ur Hochenergiephysik der OeAW, Wien, Austria
W. Adam, E. Asilar, T. Bergauer, J. Brandstetter, E. Brondolin, M. Dragicevic, J. Er ¨o, M. Flechl,M. Friedl, R. Fr ¨uhwirth , V.M. Ghete, C. Hartl, N. H ¨ormann, J. Hrubec, M. Jeitler , V. Kn ¨unz,A. K ¨onig, M. Krammer , I. Kr¨atschmer, D. Liko, I. Mikulec, D. Rabady , B. Rahbaran,H. Rohringer, J. Schieck , R. Sch ¨ofbeck, J. Strauss, W. Treberer-Treberspurg, W. Waltenberger,C.-E. Wulz National Centre for Particle and High Energy Physics, Minsk, Belarus
V. Mossolov, N. Shumeiko, J. Suarez Gonzalez
Universiteit Antwerpen, Antwerpen, Belgium
S. Alderweireldt, T. Cornelis, E.A. De Wolf, X. Janssen, A. Knutsson, J. Lauwers, S. Luyckx,S. Ochesanu, R. Rougny, M. Van De Klundert, H. Van Haevermaet, P. Van Mechelen, N. VanRemortel, A. Van Spilbeeck
Vrije Universiteit Brussel, Brussel, Belgium
S. Abu Zeid, F. Blekman, J. D’Hondt, N. Daci, I. De Bruyn, K. Deroover, N. Heracleous,J. Keaveney, S. Lowette, L. Moreels, A. Olbrechts, Q. Python, D. Strom, S. Tavernier, W. VanDoninck, P. Van Mulders, G.P. Van Onsem, I. Van Parijs
Universit´e Libre de Bruxelles, Bruxelles, Belgium
P. Barria, C. Caillol, B. Clerbaux, G. De Lentdecker, H. Delannoy, D. Dobur, G. Fasanella,L. Favart, A.P.R. Gay, A. Grebenyuk, A. L´eonard, A. Mohammadi, L. Perni`e, A. Randle-conde,T. Reis, T. Seva, L. Thomas, C. Vander Velde, P. Vanlaer, J. Wang, F. Zenoni
Ghent University, Ghent, Belgium
K. Beernaert, L. Benucci, A. Cimmino, S. Crucy, A. Fagot, G. Garcia, M. Gul, J. Mccartin,A.A. Ocampo Rios, D. Poyraz, D. Ryckbosch, S. Salva Diblen, M. Sigamani, N. Strobbe,F. Thyssen, M. Tytgat, W. Van Driessche, E. Yazgan, N. Zaganidis
Universit´e Catholique de Louvain, Louvain-la-Neuve, Belgium
S. Basegmez, C. Beluffi , O. Bondu, G. Bruno, R. Castello, A. Caudron, L. Ceard, G.G. DaSilveira, C. Delaere, T. du Pree, D. Favart, L. Forthomme, A. Giammanco , J. Hollar, A. Jafari,P. Jez, M. Komm, V. Lemaitre, A. Mertens, C. Nuttens, L. Perrini, A. Pin, K. Piotrzkowski,A. Popov , L. Quertenmont, M. Selvaggi, M. Vidal Marono Universit´e de Mons, Mons, Belgium
N. Beliy, G.H. Hammad
Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil
W.L. Ald´a J ´unior, G.A. Alves, L. Brito, M. Correa Martins Junior, T. Dos Reis Martins, C. Hensel,C. Mora Herrera, A. Moraes, M.E. Pol, P. Rebello Teles
Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
E. Belchior Batista Das Chagas, W. Carvalho, J. Chinellato , A. Cust ´odio, E.M. Da Costa,D. De Jesus Damiao, C. De Oliveira Martins, S. Fonseca De Souza, L.M. Huertas Guativa,H. Malbouisson, D. Matos Figueiredo, L. Mundim, H. Nogima, W.L. Prado Da Silva,J. Santaolalla, A. Santoro, A. Sznajder, E.J. Tonelli Manganote , A. Vilela Pereira A The CMS Collaboration
Universidade Estadual Paulista a , Universidade Federal do ABC b , S˜ao Paulo, Brazil S. Ahuja, C.A. Bernardes b , S. Dogra a , T.R. Fernandez Perez Tomei a , E.M. Gregores b ,P.G. Mercadante b , S.F. Novaes a , Sandra S. Padula a , D. Romero Abad, J.C. Ruiz Vargas Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria
A. Aleksandrov, V. Genchev , R. Hadjiiska, P. Iaydjiev, A. Marinov, S. Piperov, M. Rodozov,S. Stoykova, G. Sultanov, M. Vutova University of Sofia, Sofia, Bulgaria
A. Dimitrov, I. Glushkov, L. Litov, B. Pavlov, P. Petkov
Institute of High Energy Physics, Beijing, China
M. Ahmad, J.G. Bian, G.M. Chen, H.S. Chen, M. Chen, T. Cheng, R. Du, C.H. Jiang, R. Plestina ,F. Romeo, S.M. Shaheen, J. Tao, C. Wang, Z. Wang State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China
C. Asawatangtrakuldee, Y. Ban, G. Chen, Q. Li, S. Liu, Y. Mao, S.J. Qian, D. Wang, M. Wang,Q. Wang, Z. Xu, D. Yang, F. Zhang , L. Zhang, Z. Zhang, W. Zou Universidad de Los Andes, Bogota, Colombia
C. Avila, A. Cabrera, L.F. Chaparro Sierra, C. Florez, J.P. Gomez, B. Gomez Moreno,J.C. Sanabria
University of Split, Faculty of Electrical Engineering, Mechanical Engineering and NavalArchitecture, Split, Croatia
N. Godinovic, D. Lelas, D. Polic, I. Puljak
University of Split, Faculty of Science, Split, Croatia
Z. Antunovic, M. Kovac
Institute Rudjer Boskovic, Zagreb, Croatia
V. Brigljevic, K. Kadija, J. Luetic, L. Sudic
University of Cyprus, Nicosia, Cyprus
A. Attikis, G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis, H. Rykaczewski
Charles University, Prague, Czech Republic
M. Bodlak, M. Finger, M. Finger Jr. Academy of Scientific Research and Technology of the Arab Republic of Egypt, EgyptianNetwork of High Energy Physics, Cairo, Egypt
A. Ali , R. Aly , S. Aly , S. Elgammal , A. Ellithi Kamel , A. Lotfy , M.A. Mahmoud ,R. Masod , A. Radi National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
B. Calpas, M. Kadastik, M. Murumaa, M. Raidal, A. Tiko, C. Veelken
Department of Physics, University of Helsinki, Helsinki, Finland
P. Eerola, M. Voutilainen
Helsinki Institute of Physics, Helsinki, Finland
J. H¨ark ¨onen, V. Karim¨aki, R. Kinnunen, T. Lamp´en, K. Lassila-Perini, S. Lehti, T. Lind´en,P. Luukka, T. M¨aenp¨a¨a, T. Peltola, E. Tuominen, J. Tuominiemi, E. Tuovinen, L. Wendland
Lappeenranta University of Technology, Lappeenranta, Finland
J. Talvitie, T. Tuuva DSM/IRFU, CEA/Saclay, Gif-sur-Yvette, France
M. Besancon, F. Couderc, M. Dejardin, D. Denegri, B. Fabbro, J.L. Faure, C. Favaro, F. Ferri,S. Ganjour, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, E. Locci, J. Malcles,J. Rander, A. Rosowsky, M. Titov, A. Zghiche
Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France
S. Baffioni, F. Beaudette, P. Busson, L. Cadamuro, E. Chapon, C. Charlot, T. Dahms,O. Davignon, N. Filipovic, A. Florent, R. Granier de Cassagnac, L. Mastrolorenzo, P. Min´e,I.N. Naranjo, M. Nguyen, C. Ochando, G. Ortona, P. Paganini, S. Regnard, R. Salerno,J.B. Sauvan, Y. Sirois, T. Strebler, Y. Yilmaz, A. Zabi
Institut Pluridisciplinaire Hubert Curien, Universit´e de Strasbourg, Universit´e de HauteAlsace Mulhouse, CNRS/IN2P3, Strasbourg, France
J.-L. Agram , J. Andrea, A. Aubin, D. Bloch, J.-M. Brom, M. Buttignol, E.C. Chabert,N. Chanon, C. Collard, E. Conte , J.-C. Fontaine , D. Gel´e, U. Goerlach, C. Goetzmann, A.-C. Le Bihan, J.A. Merlin , K. Skovpen, P. Van Hove Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique des Particules,CNRS/IN2P3, Villeurbanne, France
S. Gadrat
Universit´e de Lyon, Universit´e Claude Bernard Lyon 1, CNRS-IN2P3, Institut de PhysiqueNucl´eaire de Lyon, Villeurbanne, France
S. Beauceron, N. Beaupere, C. Bernet , G. Boudoul , E. Bouvier, S. Brochet, C.A. CarrilloMontoya, J. Chasserat, R. Chierici, D. Contardo, B. Courbon, P. Depasse, H. El Mamouni,J. Fan, J. Fay, S. Gascon, M. Gouzevitch, B. Ille, I.B. Laktineh, M. Lethuillier, L. Mirabito,A.L. Pequegnot, S. Perries, J.D. Ruiz Alvarez, D. Sabes, L. Sgandurra, V. Sordini, M. VanderDonckt, P. Verdier, S. Viret, H. Xiao Institute of High Energy Physics and Informatization, Tbilisi State University, Tbilisi,Georgia
D. Lomidze
RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany
C. Autermann, S. Beranek, M. Bontenackels, M. Edelhoff, L. Feld, A. Heister, M.K. Kiesel,K. Klein, M. Lipinski, A. Ostapchuk, M. Preuten, F. Raupach, J. Sammet, S. Schael, J.F. Schulte,T. Verlage, H. Weber, B. Wittmer, V. Zhukov RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany
M. Ata, M. Brodski, E. Dietz-Laursonn, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg,T. Esch, R. Fischer, A. G ¨uth, T. Hebbeker, C. Heidemann, K. Hoepfner, D. Klingebiel,S. Knutzen, P. Kreuzer, M. Merschmeyer, A. Meyer, P. Millet, M. Olschewski, K. Padeken,P. Papacz, T. Pook, M. Radziej, H. Reithler, M. Rieger, S.A. Schmitz, L. Sonnenschein,D. Teyssier, S. Th ¨uer
RWTH Aachen University, III. Physikalisches Institut B, Aachen, Germany
V. Cherepanov, Y. Erdogan, G. Fl ¨ugge, H. Geenen, M. Geisler, W. Haj Ahmad, F. Hoehle,B. Kargoll, T. Kress, Y. Kuessel, A. K ¨unsken, J. Lingemann , A. Nowack, I.M. Nugent,C. Pistone, O. Pooth, A. Stahl Deutsches Elektronen-Synchrotron, Hamburg, Germany
M. Aldaya Martin, I. Asin, N. Bartosik, O. Behnke, U. Behrens, A.J. Bell, K. Borras,A. Burgmeier, A. Cakir, L. Calligaris, A. Campbell, S. Choudhury, F. Costanza, C. Diez Pardos,G. Dolinska, S. Dooling, T. Dorland, G. Eckerlin, D. Eckstein, T. Eichhorn, G. Flucke, J. Garay A The CMS Collaboration
Garcia, A. Geiser, A. Gizhko, P. Gunnellini, J. Hauk, M. Hempel , H. Jung, A. Kalogeropoulos,O. Karacheban , M. Kasemann, P. Katsas, J. Kieseler, C. Kleinwort, I. Korol, W. Lange,J. Leonard, K. Lipka, A. Lobanov, R. Mankel, I. Marfin , I.-A. Melzer-Pellmann, A.B. Meyer,G. Mittag, J. Mnich, A. Mussgiller, S. Naumann-Emme, A. Nayak, E. Ntomari, H. Perrey,D. Pitzl, R. Placakyte, A. Raspereza, P.M. Ribeiro Cipriano, B. Roland, M. ¨O. Sahin, J. Salfeld-Nebgen, P. Saxena, T. Schoerner-Sadenius, M. Schr ¨oder, C. Seitz, S. Spannagel, C. Wissing University of Hamburg, Hamburg, Germany
V. Blobel, M. Centis Vignali, A.R. Draeger, J. Erfle, E. Garutti, K. Goebel, D. Gonzalez,M. G ¨orner, J. Haller, M. Hoffmann, R.S. H ¨oing, A. Junkes, H. Kirschenmann, R. Klanner,R. Kogler, T. Lapsien, T. Lenz, I. Marchesini, D. Marconi, M. Meyer, D. Nowatschin, J. Ott,T. Peiffer, A. Perieanu, N. Pietsch, J. Poehlsen, D. Rathjens, C. Sander, H. Schettler, P. Schleper,E. Schlieckau, A. Schmidt, M. Seidel, V. Sola, H. Stadie, G. Steinbr ¨uck, H. Tholen, D. Troendle,E. Usai, L. Vanelderen, A. Vanhoefer
Institut f ¨ur Experimentelle Kernphysik, Karlsruhe, Germany
M. Akbiyik, C. Barth, C. Baus, J. Berger, C. B ¨oser, E. Butz, T. Chwalek, F. Colombo, W. DeBoer, A. Descroix, A. Dierlamm, M. Feindt, F. Frensch, M. Giffels, A. Gilbert, F. Hartmann ,U. Husemann, I. Katkov , A. Kornmayer , P. Lobelle Pardo, M.U. Mozer, T. M ¨uller, Th. M ¨uller,M. Plagge, G. Quast, K. Rabbertz, S. R ¨ocker, F. Roscher, H.J. Simonis, F.M. Stober, R. Ulrich,J. Wagner-Kuhr, S. Wayand, T. Weiler, C. W ¨ohrmann, R. Wolf Institute of Nuclear and Particle Physics (INPP), NCSR Demokritos, Aghia Paraskevi,Greece
G. Anagnostou, G. Daskalakis, T. Geralis, V.A. Giakoumopoulou, A. Kyriakis, D. Loukas,A. Markou, A. Psallidas, I. Topsis-Giotis
University of Athens, Athens, Greece
A. Agapitos, S. Kesisoglou, A. Panagiotou, N. Saoulidou, E. Tziaferi
University of Io´annina, Io´annina, Greece
I. Evangelou, G. Flouris, C. Foudas, P. Kokkas, N. Loukas, N. Manthos, I. Papadopoulos,E. Paradas, J. Strologas
Wigner Research Centre for Physics, Budapest, Hungary
G. Bencze, C. Hajdu, A. Hazi, P. Hidas, D. Horvath , F. Sikler, V. Veszpremi, G. Vesztergombi ,A.J. Zsigmond Institute of Nuclear Research ATOMKI, Debrecen, Hungary
N. Beni, S. Czellar, J. Karancsi , J. Molnar, J. Palinkas, Z. Szillasi University of Debrecen, Debrecen, Hungary
M. Bart ´ok , A. Makovec, P. Raics, Z.L. Trocsanyi National Institute of Science Education and Research, Bhubaneswar, India
P. Mal, K. Mandal, N. Sahoo, S.K. Swain
Panjab University, Chandigarh, India
S. Bansal, S.B. Beri, V. Bhatnagar, R. Chawla, R. Gupta, U.Bhawandeep, A.K. Kalsi, A. Kaur,M. Kaur, R. Kumar, A. Mehta, M. Mittal, N. Nishu, J.B. Singh
University of Delhi, Delhi, India
Ashok Kumar, Arun Kumar, A. Bhardwaj, B.C. Choudhary, A. Kumar, S. Malhotra,M. Naimuddin, K. Ranjan, R. Sharma, V. Sharma9
Ashok Kumar, Arun Kumar, A. Bhardwaj, B.C. Choudhary, A. Kumar, S. Malhotra,M. Naimuddin, K. Ranjan, R. Sharma, V. Sharma9 Saha Institute of Nuclear Physics, Kolkata, India
S. Banerjee, S. Bhattacharya, K. Chatterjee, S. Dey, S. Dutta, B. Gomber, Sa. Jain, Sh. Jain,R. Khurana, N. Majumdar, A. Modak, K. Mondal, S. Mukherjee, S. Mukhopadhyay, A. Roy,D. Roy, S. Roy Chowdhury, S. Sarkar, M. Sharan
Bhabha Atomic Research Centre, Mumbai, India
A. Abdulsalam, D. Dutta, V. Jha, V. Kumar, A.K. Mohanty , L.M. Pant, P. Shukla, A. Topkar Tata Institute of Fundamental Research, Mumbai, India
T. Aziz, S. Banerjee, S. Bhowmik , R.M. Chatterjee, R.K. Dewanjee, S. Dugad, S. Ganguly,S. Ghosh, M. Guchait, A. Gurtu , G. Kole, S. Kumar, M. Maity , G. Majumder, K. Mazumdar,G.B. Mohanty, B. Parida, K. Sudhakar, N. Sur, B. Sutar, N. Wickramage Indian Institute of Science Education and Research (IISER), Pune, India
S. Sharma
Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
H. Bakhshiansohi, H. Behnamian, S.M. Etesami , A. Fahim , R. Goldouzian, M. Khakzad,M. Mohammadi Najafabadi, M. Naseri, S. Paktinat Mehdiabadi, F. Rezaei Hosseinabadi,B. Safarzadeh , M. Zeinali University College Dublin, Dublin, Ireland
M. Felcini, M. Grunewald
INFN Sezione di Bari a , Universit`a di Bari b , Politecnico di Bari c , Bari, Italy M. Abbrescia a , b , C. Calabria a , b , C. Caputo a , b , S.S. Chhibra a , b , A. Colaleo a , D. Creanza a , c ,L. Cristella a , b , N. De Filippis a , c , M. De Palma a , b , L. Fiore a , G. Iaselli a , c , G. Maggi a , c , M. Maggi a ,G. Miniello a , b , S. My a , c , S. Nuzzo a , b , A. Pompili a , b , G. Pugliese a , c , R. Radogna a , b ,2 , A. Ranieri a ,G. Selvaggi a , b , A. Sharma a , L. Silvestris a ,2 , R. Venditti a , b , P. Verwilligen a INFN Sezione di Bologna a , Universit`a di Bologna b , Bologna, Italy G. Abbiendi a , C. Battilana, A.C. Benvenuti a , D. Bonacorsi a , b , S. Braibant-Giacomelli a , b ,L. Brigliadori a , b , R. Campanini a , b , P. Capiluppi a , b , A. Castro a , b , F.R. Cavallo a , G. Codispoti a , b ,M. Cuffiani a , b , G.M. Dallavalle a , F. Fabbri a , A. Fanfani a , b , D. Fasanella a , b , P. Giacomelli a ,C. Grandi a , L. Guiducci a , b , S. Marcellini a , G. Masetti a , A. Montanari a , F.L. Navarria a , b ,A. Perrotta a , A.M. Rossi a , b , T. Rovelli a , b , G.P. Siroli a , b , N. Tosi a , b , R. Travaglini a , b INFN Sezione di Catania a , Universit`a di Catania b , CSFNSM c , Catania, Italy G. Cappello a , M. Chiorboli a , b , S. Costa a , b , F. Giordano a , c ,2 , R. Potenza a , b , A. Tricomi a , b ,C. Tuve a , b INFN Sezione di Firenze a , Universit`a di Firenze b , Firenze, Italy G. Barbagli a , V. Ciulli a , b , C. Civinini a , R. D’Alessandro a , b , E. Focardi a , b , E. Gallo a , S. Gonzi a , b ,V. Gori a , b , P. Lenzi a , b , M. Meschini a , S. Paoletti a , G. Sguazzoni a , A. Tropiano a , b , L. Viliani a , b INFN Laboratori Nazionali di Frascati, Frascati, Italy
L. Benussi, S. Bianco, F. Fabbri, D. Piccolo
INFN Sezione di Genova a , Universit`a di Genova b , Genova, Italy V. Calvelli a , b , F. Ferro a , M. Lo Vetere a , b , E. Robutti a , S. Tosi a , b INFN Sezione di Milano-Bicocca a , Universit`a di Milano-Bicocca b , Milano, Italy M.E. Dinardo a , b , S. Fiorendi a , b , S. Gennai a ,2 , R. Gerosa a , b , A. Ghezzi a , b , P. Govoni a , b ,M.T. Lucchini a , b ,2 , S. Malvezzi a , R.A. Manzoni a , b , B. Marzocchi a , b ,2 , D. Menasce a , L. Moroni a ,M. Paganoni a , b , D. Pedrini a , S. Ragazzi a , b , N. Redaelli a , T. Tabarelli de Fatis a , b A The CMS Collaboration
INFN Sezione di Napoli a , Universit`a di Napoli ’Federico II’ b , Napoli, Italy, Universit`a dellaBasilicata c , Potenza, Italy, Universit`a G. Marconi d , Roma, Italy S. Buontempo a , N. Cavallo a , c , S. Di Guida a , d ,2 , M. Esposito a , b , F. Fabozzi a , c , A.O.M. Iorio a , b ,G. Lanza a , L. Lista a , S. Meola a , d ,2 , M. Merola a , P. Paolucci a ,2 , C. Sciacca a , b INFN Sezione di Padova a , Universit`a di Padova b , Padova, Italy, Universit`a di Trento c ,Trento, Italy P. Azzi a ,2 , N. Bacchetta a , D. Bisello a , b , A. Branca a , b , R. Carlin a , b , A. Carvalho AntunesDe Oliveira a , b , P. Checchia a , M. Dall’Osso a , b , T. Dorigo a , F. Gasparini a , b , U. Gasparini a , b ,A. Gozzelino a , S. Lacaprara a , M. Margoni a , b , A.T. Meneguzzo a , b , F. Montecassiano a ,M. Passaseo a , J. Pazzini a , b , N. Pozzobon a , b , P. Ronchese a , b , F. Simonetto a , b , E. Torassa a ,M. Tosi a , b , M. Zanetti a , b , P. Zotto a , b , A. Zucchetta a , b , G. Zumerle a , b INFN Sezione di Pavia a , Universit`a di Pavia b , Pavia, Italy M. Gabusi a , b , A. Magnani a , S.P. Ratti a , b , V. Re a , C. Riccardi a , b , P. Salvini a , I. Vai a , P. Vitulo a , b INFN Sezione di Perugia a , Universit`a di Perugia b , Perugia, Italy L. Alunni Solestizi a , b , M. Biasini a , b , G.M. Bilei a , D. Ciangottini a , b ,2 , L. Fan `o a , b , P. Lariccia a , b ,G. Mantovani a , b , M. Menichelli a , A. Saha a , A. Santocchia a , b , A. Spiezia a , b ,2 INFN Sezione di Pisa a , Universit`a di Pisa b , Scuola Normale Superiore di Pisa c , Pisa, Italy K. Androsov a ,27 , P. Azzurri a , G. Bagliesi a , J. Bernardini a , T. Boccali a , G. Broccolo a , c , R. Castaldi a ,M.A. Ciocci a ,27 , R. Dell’Orso a , S. Donato a , c ,2 , G. Fedi, F. Fiori a , c , L. Fo`a a , c † , A. Giassi a ,M.T. Grippo a ,27 , F. Ligabue a , c , T. Lomtadze a , L. Martini a , b , A. Messineo a , b , C.S. Moon a ,28 ,F. Palla a , A. Rizzi a , b , A. Savoy-Navarro a ,29 , A.T. Serban a , P. Spagnolo a , P. Squillacioti a ,27 ,R. Tenchini a , G. Tonelli a , b , A. Venturi a , P.G. Verdini a INFN Sezione di Roma a , Universit`a di Roma b , Roma, Italy L. Barone a , b , F. Cavallari a , G. D’imperio a , b , D. Del Re a , b , M. Diemoz a , S. Gelli a , b , C. Jorda a ,E. Longo a , b , F. Margaroli a , b , P. Meridiani a , F. Micheli a , b , G. Organtini a , b , R. Paramatti a ,F. Preiato a , b , S. Rahatlou a , b , C. Rovelli a , F. Santanastasio a , b , L. Soffi a , b , P. Traczyk a , b ,2 INFN Sezione di Torino a , Universit`a di Torino b , Torino, Italy, Universit`a del PiemonteOrientale c , Novara, Italy N. Amapane a , b , R. Arcidiacono a , c , S. Argiro a , b , M. Arneodo a , c , R. Bellan a , b , C. Biino a ,N. Cartiglia a , S. Casasso a , b , M. Costa a , b , R. Covarelli a , b , P. De Remigis a , A. Degano a , b ,N. Demaria a , L. Finco a , b ,2 , B. Kiani a , b , C. Mariotti a , S. Maselli a , E. Migliore a , b , V. Monaco a , b ,M. Musich a , M.M. Obertino a , c , L. Pacher a , b , N. Pastrone a , M. Pelliccioni a , G.L. Pinna Angioni a , b ,A. Romero a , b , M. Ruspa a , c , R. Sacchi a , b , A. Solano a , b , A. Staiano a INFN Sezione di Trieste a , Universit`a di Trieste b , Trieste, Italy S. Belforte a , V. Candelise a , b ,2 , M. Casarsa a , F. Cossutti a , G. Della Ricca a , b , B. Gobbo a , C. LaLicata a , b , M. Marone a , b , A. Schizzi a , b , T. Umer a , b , A. Zanetti a Kangwon National University, Chunchon, Korea
S. Chang, A. Kropivnitskaya, S.K. Nam
Kyungpook National University, Daegu, Korea
D.H. Kim, G.N. Kim, M.S. Kim, D.J. Kong, S. Lee, Y.D. Oh, H. Park, A. Sakharov, D.C. Son
Chonbuk National University, Jeonju, Korea
H. Kim, T.J. Kim, M.S. Ryu Chonnam National University, Institute for Universe and Elementary Particles, Kwangju,Korea
S. Song
Korea University, Seoul, Korea
S. Choi, Y. Go, D. Gyun, B. Hong, M. Jo, H. Kim, Y. Kim, B. Lee, K. Lee, K.S. Lee, S. Lee,S.K. Park, Y. Roh
Seoul National University, Seoul, Korea
H.D. Yoo
University of Seoul, Seoul, Korea
M. Choi, J.H. Kim, J.S.H. Lee, I.C. Park, G. Ryu
Sungkyunkwan University, Suwon, Korea
Y. Choi, Y.K. Choi, J. Goh, D. Kim, E. Kwon, J. Lee, I. Yu
Vilnius University, Vilnius, Lithuania
A. Juodagalvis, J. Vaitkus
National Centre for Particle Physics, Universiti Malaya, Kuala Lumpur, Malaysia
Z.A. Ibrahim, J.R. Komaragiri, M.A.B. Md Ali , F. Mohamad Idris, W.A.T. Wan Abdullah Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico
E. Casimiro Linares, H. Castilla-Valdez, E. De La Cruz-Burelo, I. Heredia-de La Cruz,A. Hernandez-Almada, R. Lopez-Fernandez, G. Ramirez Sanchez, A. Sanchez-Hernandez
Universidad Iberoamericana, Mexico City, Mexico
S. Carrillo Moreno, F. Vazquez Valencia
Benemerita Universidad Autonoma de Puebla, Puebla, Mexico
S. Carpinteyro, I. Pedraza, H.A. Salazar Ibarguen
Universidad Aut ´onoma de San Luis Potos´ı, San Luis Potos´ı, Mexico
A. Morelos Pineda
University of Auckland, Auckland, New Zealand
D. Krofcheck
University of Canterbury, Christchurch, New Zealand
P.H. Butler, S. Reucroft
National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan
A. Ahmad, M. Ahmad, Q. Hassan, H.R. Hoorani, W.A. Khan, T. Khurshid, M. Shoaib
National Centre for Nuclear Research, Swierk, Poland
H. Bialkowska, M. Bluj, B. Boimska, T. Frueboes, M. G ´orski, M. Kazana, K. Nawrocki,K. Romanowska-Rybinska, M. Szleper, P. Zalewski
Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland
G. Brona, K. Bunkowski, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski, M. Misiura,M. Olszewski, M. Walczak
Laborat ´orio de Instrumenta¸c˜ao e F´ısica Experimental de Part´ıculas, Lisboa, Portugal
P. Bargassa, C. Beir˜ao Da Cruz E Silva, A. Di Francesco, P. Faccioli, P.G. Ferreira Parracho,M. Gallinaro, L. Lloret Iglesias, F. Nguyen, J. Rodrigues Antunes, J. Seixas, O. Toldaiev,D. Vadruccio, J. Varela, P. Vischia A The CMS Collaboration
Joint Institute for Nuclear Research, Dubna, Russia
S. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, I. Gorbunov, A. Kamenev, V. Karjavin,V. Konoplyanikov, A. Lanev, A. Malakhov, V. Matveev , P. Moisenz, V. Palichik, V. Perelygin,S. Shmatov, S. Shulha, N. Skatchkov, V. Smirnov, T. Toriashvili , A. Zarubin Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), Russia
V. Golovtsov, Y. Ivanov, V. Kim , E. Kuznetsova, P. Levchenko, V. Murzin, V. Oreshkin,I. Smirnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev Institute for Nuclear Research, Moscow, Russia
Yu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, A. Karneyeu, M. Kirsanov, N. Krasnikov,A. Pashenkov, D. Tlisov, A. Toropin
Institute for Theoretical and Experimental Physics, Moscow, Russia
V. Epshteyn, V. Gavrilov, N. Lychkovskaya, V. Popov, I. Pozdnyakov, G. Safronov,A. Spiridonov, E. Vlasov, A. Zhokin
P.N. Lebedev Physical Institute, Moscow, Russia
V. Andreev, M. Azarkin , I. Dremin , M. Kirakosyan, A. Leonidov , G. Mesyats, S.V. Rusakov,A. Vinogradov Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow,Russia
A. Baskakov, A. Belyaev, E. Boos, M. Dubinin , L. Dudko, A. Ershov, A. Gribushin,V. Klyukhin, O. Kodolova, I. Lokhtin, I. Myagkov, S. Obraztsov, S. Petrushanko, V. Savrin,A. Snigirev State Research Center of Russian Federation, Institute for High Energy Physics, Protvino,Russia
I. Azhgirey, I. Bayshev, S. Bitioukov, V. Kachanov, A. Kalinin, D. Konstantinov, V. Krychkine,V. Petrov, R. Ryutin, A. Sobol, L. Tourtchanovitch, S. Troshin, N. Tyurin, A. Uzunian, A. Volkov
University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade,Serbia
P. Adzic , M. Ekmedzic, J. Milosevic, V. Rekovic Centro de Investigaciones Energ´eticas Medioambientales y Tecnol ´ogicas (CIEMAT),Madrid, Spain
J. Alcaraz Maestre, E. Calvo, M. Cerrada, M. Chamizo Llatas, N. Colino, B. De La Cruz,A. Delgado Peris, D. Dom´ınguez V´azquez, A. Escalante Del Valle, C. Fernandez Bedoya,J.P. Fern´andez Ramos, J. Flix, M.C. Fouz, P. Garcia-Abia, O. Gonzalez Lopez, S. Goy Lopez,J.M. Hernandez, M.I. Josa, E. Navarro De Martino, A. P´erez-Calero Yzquierdo, J. Puerta Pelayo,A. Quintario Olmeda, I. Redondo, L. Romero, M.S. Soares
Universidad Aut ´onoma de Madrid, Madrid, Spain
C. Albajar, J.F. de Troc ´oniz, M. Missiroli, D. Moran
Universidad de Oviedo, Oviedo, Spain
H. Brun, J. Cuevas, J. Fernandez Menendez, S. Folgueras, I. Gonzalez Caballero, E. PalenciaCortezon, J.M. Vizan Garcia
Instituto de F´ısica de Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, Spain
J.A. Brochero Cifuentes, I.J. Cabrillo, A. Calderon, J.R. Casti ˜neiras De Saa, J. DuarteCampderros, M. Fernandez, G. Gomez, A. Graziano, A. Lopez Virto, J. Marco, R. Marco, C. Martinez Rivero, F. Matorras, F.J. Munoz Sanchez, J. Piedra Gomez, T. Rodrigo,A.Y. Rodr´ıguez-Marrero, A. Ruiz-Jimeno, L. Scodellaro, I. Vila, R. Vilar Cortabitarte
CERN, European Organization for Nuclear Research, Geneva, Switzerland
D. Abbaneo, E. Auffray, G. Auzinger, M. Bachtis, P. Baillon, A.H. Ball, D. Barney, A. Benaglia,J. Bendavid, L. Benhabib, J.F. Benitez, G.M. Berruti, P. Bloch, A. Bocci, A. Bonato, C. Botta,H. Breuker, T. Camporesi, G. Cerminara, S. Colafranceschi , M. D’Alfonso, D. d’Enterria,A. Dabrowski, V. Daponte, A. David, M. De Gruttola, F. De Guio, A. De Roeck, S. De Visscher,E. Di Marco, M. Dobson, M. Dordevic, N. Dupont-Sagorin, A. Elliott-Peisert, G. Franzoni,W. Funk, D. Gigi, K. Gill, D. Giordano, M. Girone, F. Glege, R. Guida, S. Gundacker, M. Guthoff,J. Hammer, M. Hansen, P. Harris, J. Hegeman, V. Innocente, P. Janot, M.J. Kortelainen,K. Kousouris, K. Krajczar, P. Lecoq, C. Lourenc¸o, N. Magini, L. Malgeri, M. Mannelli,J. Marrouche, A. Martelli, L. Masetti, F. Meijers, S. Mersi, E. Meschi, F. Moortgat, S. Morovic,M. Mulders, M.V. Nemallapudi, H. Neugebauer, S. Orfanelli, L. Orsini, L. Pape, E. Perez,A. Petrilli, G. Petrucciani, A. Pfeiffer, D. Piparo, A. Racz, G. Rolandi , M. Rovere, M. Ruan,H. Sakulin, C. Sch¨afer, C. Schwick, A. Sharma, P. Silva, M. Simon, P. Sphicas , D. Spiga,J. Steggemann, B. Stieger, M. Stoye, Y. Takahashi, D. Treille, A. Tsirou, G.I. Veres , N. Wardle,H.K. W ¨ohri, A. Zagozdzinska , W.D. Zeuner Paul Scherrer Institut, Villigen, Switzerland
W. Bertl, K. Deiters, W. Erdmann, R. Horisberger, Q. Ingram, H.C. Kaestli, D. Kotlinski,U. Langenegger, T. Rohe
Institute for Particle Physics, ETH Zurich, Zurich, Switzerland
F. Bachmair, L. B¨ani, L. Bianchini, M.A. Buchmann, B. Casal, G. Dissertori, M. Dittmar,M. Doneg`a, M. D ¨unser, P. Eller, C. Grab, C. Heidegger, D. Hits, J. Hoss, G. Kasieczka,W. Lustermann, B. Mangano, A.C. Marini, M. Marionneau, P. Martinez Ruiz del Arbol,M. Masciovecchio, D. Meister, N. Mohr, P. Musella, F. Nessi-Tedaldi, F. Pandolfi, J. Pata,F. Pauss, L. Perrozzi, M. Peruzzi, M. Quittnat, M. Rossini, A. Starodumov , M. Takahashi,V.R. Tavolaro, K. Theofilatos, R. Wallny, H.A. Weber Universit¨at Z ¨urich, Zurich, Switzerland
T.K. Aarrestad, C. Amsler , M.F. Canelli, V. Chiochia, A. De Cosa, C. Galloni, A. Hinzmann,T. Hreus, B. Kilminster, C. Lange, J. Ngadiuba, D. Pinna, P. Robmann, F.J. Ronga, D. Salerno,S. Taroni, Y. Yang National Central University, Chung-Li, Taiwan
M. Cardaci, K.H. Chen, T.H. Doan, C. Ferro, M. Konyushikhin, C.M. Kuo, W. Lin, Y.J. Lu,R. Volpe, S.S. Yu
National Taiwan University (NTU), Taipei, Taiwan
P. Chang, Y.H. Chang, Y.W. Chang, Y. Chao, K.F. Chen, P.H. Chen, C. Dietz, U. Grundler, W.-S. Hou, Y. Hsiung, Y.F. Liu, R.-S. Lu, M. Mi ˜nano Moya, E. Petrakou, J.f. Tsai, Y.M. Tzeng,R. Wilken
Chulalongkorn University, Faculty of Science, Department of Physics, Bangkok, Thailand
B. Asavapibhop, G. Singh, N. Srimanobhas, N. Suwonjandee
Cukurova University, Adana, Turkey
A. Adiguzel, S. Cerci , C. Dozen, S. Girgis, G. Gokbulut, Y. Guler, E. Gurpinar, I. Hos,E.E. Kangal , A. Kayis Topaksu, G. Onengut , K. Ozdemir , S. Ozturk , B. Tali ,H. Topakli , M. Vergili, C. Zorbilmez A The CMS Collaboration
Middle East Technical University, Physics Department, Ankara, Turkey
I.V. Akin, B. Bilin, S. Bilmis, B. Isildak , G. Karapinar , U.E. Surat, M. Yalvac, M. Zeyrek Bogazici University, Istanbul, Turkey
E.A. Albayrak , E. G ¨ulmez, M. Kaya , O. Kaya , T. Yetkin Istanbul Technical University, Istanbul, Turkey
K. Cankocak, Y.O. G ¨unaydin , F.I. Vardarlı Institute for Scintillation Materials of National Academy of Science of Ukraine, Kharkov,Ukraine
B. Grynyov
National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, Ukraine
L. Levchuk, P. Sorokin
University of Bristol, Bristol, United Kingdom
R. Aggleton, F. Ball, L. Beck, J.J. Brooke, E. Clement, D. Cussans, H. Flacher, J. Goldstein,M. Grimes, G.P. Heath, H.F. Heath, J. Jacob, L. Kreczko, C. Lucas, Z. Meng, D.M. Newbold ,S. Paramesvaran, A. Poll, T. Sakuma, S. Seif El Nasr-storey, S. Senkin, D. Smith, V.J. Smith Rutherford Appleton Laboratory, Didcot, United Kingdom
K.W. Bell, A. Belyaev , C. Brew, R.M. Brown, D.J.A. Cockerill, J.A. Coughlan, K. Harder,S. Harper, E. Olaiya, D. Petyt, C.H. Shepherd-Themistocleous, A. Thea, I.R. Tomalin,T. Williams, W.J. Womersley, S.D. Worm Imperial College, London, United Kingdom
M. Baber, R. Bainbridge, O. Buchmuller, A. Bundock, D. Burton, M. Citron, D. Colling,L. Corpe, N. Cripps, P. Dauncey, G. Davies, A. De Wit, M. Della Negra, P. Dunne, A. Elwood,W. Ferguson, J. Fulcher, D. Futyan, G. Hall, G. Iles, G. Karapostoli, M. Kenzie, R. Lane,R. Lucas , L. Lyons, A.-M. Magnan, S. Malik, J. Nash, A. Nikitenko , J. Pela, M. Pesaresi,K. Petridis, D.M. Raymond, A. Richards, A. Rose, C. Seez, P. Sharp † , A. Tapper, K. Uchida,M. Vazquez Acosta, T. Virdee, S.C. Zenz Brunel University, Uxbridge, United Kingdom
J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, D. Leggat, D. Leslie, I.D. Reid, P. Symonds,L. Teodorescu, M. Turner
Baylor University, Waco, USA
J. Dittmann, K. Hatakeyama, A. Kasmi, H. Liu, N. Pastika, T. Scarborough
The University of Alabama, Tuscaloosa, USA
O. Charaf, S.I. Cooper, C. Henderson, P. Rumerio
Boston University, Boston, USA
A. Avetisyan, T. Bose, C. Fantasia, D. Gastler, P. Lawson, D. Rankin, C. Richardson, J. Rohlf,J. St. John, L. Sulak, D. Zou
Brown University, Providence, USA
J. Alimena, E. Berry, S. Bhattacharya, D. Cutts, Z. Demiragli, N. Dhingra, A. Ferapontov,A. Garabedian, U. Heintz, E. Laird, G. Landsberg, Z. Mao, M. Narain, S. Sagir, T. Sinthuprasith
University of California, Davis, Davis, USA
R. Breedon, G. Breto, M. Calderon De La Barca Sanchez, S. Chauhan, M. Chertok, J. Conway,R. Conway, P.T. Cox, R. Erbacher, M. Gardner, W. Ko, R. Lander, M. Mulhearn, D. Pellett, J. Pilot,F. Ricci-Tam, S. Shalhout, J. Smith, M. Squires, D. Stolp, M. Tripathi, S. Wilbur, R. Yohay University of California, Los Angeles, USA
R. Cousins, P. Everaerts, C. Farrell, J. Hauser, M. Ignatenko, G. Rakness, D. Saltzberg,E. Takasugi, V. Valuev, M. Weber
University of California, Riverside, Riverside, USA
K. Burt, R. Clare, J. Ellison, J.W. Gary, G. Hanson, J. Heilman, M. Ivova Rikova, P. Jandir,E. Kennedy, F. Lacroix, O.R. Long, A. Luthra, M. Malberti, M. Olmedo Negrete, A. Shrinivas,S. Sumowidagdo, H. Wei, S. Wimpenny
University of California, San Diego, La Jolla, USA
J.G. Branson, G.B. Cerati, S. Cittolin, R.T. D’Agnolo, A. Holzner, R. Kelley, D. Klein,D. Kovalskyi, J. Letts, I. Macneill, D. Olivito, S. Padhi, C. Palmer, M. Pieri, M. Sani, V. Sharma,S. Simon, M. Tadel, Y. Tu, A. Vartak, S. Wasserbaech , C. Welke, F. W ¨urthwein, A. Yagil, G. ZeviDella Porta University of California, Santa Barbara, Santa Barbara, USA
D. Barge, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, K. Flowers, M. Franco Sevilla,P. Geffert, C. George, F. Golf, L. Gouskos, J. Gran, J. Incandela, C. Justus, N. Mccoll, S.D. Mullin,J. Richman, D. Stuart, W. To, C. West, J. Yoo
California Institute of Technology, Pasadena, USA
D. Anderson, A. Apresyan, A. Bornheim, J. Bunn, Y. Chen, J. Duarte, A. Mott, H.B. Newman,C. Pena, M. Pierini, M. Spiropulu, J.R. Vlimant, S. Xie, R.Y. Zhu
Carnegie Mellon University, Pittsburgh, USA
V. Azzolini, A. Calamba, B. Carlson, T. Ferguson, Y. Iiyama, M. Paulini, J. Russ, M. Sun,H. Vogel, I. Vorobiev
University of Colorado at Boulder, Boulder, USA
J.P. Cumalat, W.T. Ford, A. Gaz, F. Jensen, A. Johnson, M. Krohn, T. Mulholland, U. Nauenberg,J.G. Smith, K. Stenson, S.R. Wagner
Cornell University, Ithaca, USA
J. Alexander, A. Chatterjee, J. Chaves, J. Chu, S. Dittmer, N. Eggert, N. Mirman, G. NicolasKaufman, J.R. Patterson, A. Ryd, L. Skinnari, W. Sun, S.M. Tan, W.D. Teo, J. Thom, J. Thompson,J. Tucker, Y. Weng, P. Wittich
Fermi National Accelerator Laboratory, Batavia, USA
S. Abdullin, M. Albrow, J. Anderson, G. Apollinari, L.A.T. Bauerdick, A. Beretvas, J. Berryhill,P.C. Bhat, G. Bolla, K. Burkett, J.N. Butler, H.W.K. Cheung, F. Chlebana, S. Cihangir, V.D. Elvira,I. Fisk, J. Freeman, E. Gottschalk, L. Gray, D. Green, S. Gr ¨unendahl, O. Gutsche, J. Hanlon,D. Hare, R.M. Harris, J. Hirschauer, B. Hooberman, Z. Hu, S. Jindariani, M. Johnson, U. Joshi,A.W. Jung, B. Klima, B. Kreis, S. Kwan † , S. Lammel, J. Linacre, D. Lincoln, R. Lipton,T. Liu, R. Lopes De S´a, J. Lykken, K. Maeshima, J.M. Marraffino, V.I. Martinez Outschoorn,S. Maruyama, D. Mason, P. McBride, P. Merkel, K. Mishra, S. Mrenna, S. Nahn, C. Newman-Holmes, V. O’Dell, O. Prokofyev, E. Sexton-Kennedy, A. Soha, W.J. Spalding, L. Spiegel,L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger, E.W. Vaandering, C. Vernieri, M. Verzocchi,R. Vidal, A. Whitbeck, F. Yang, H. Yin University of Florida, Gainesville, USA
D. Acosta, P. Avery, P. Bortignon, D. Bourilkov, A. Carnes, M. Carver, D. Curry, S. Das, G.P. DiGiovanni, R.D. Field, M. Fisher, I.K. Furic, J. Hugon, J. Konigsberg, A. Korytov, T. Kypreos,J.F. Low, P. Ma, K. Matchev, H. Mei, P. Milenovic , G. Mitselmakher, L. Muniz, D. Rank,A. Rinkevicius, L. Shchutska, M. Snowball, D. Sperka, S.J. Wang, J. Yelton A The CMS Collaboration
Florida International University, Miami, USA
S. Hewamanage, S. Linn, P. Markowitz, G. Martinez, J.L. Rodriguez
Florida State University, Tallahassee, USA
A. Ackert, J.R. Adams, T. Adams, A. Askew, J. Bochenek, B. Diamond, J. Haas, S. Hagopian,V. Hagopian, K.F. Johnson, A. Khatiwada, H. Prosper, V. Veeraraghavan, M. Weinberg
Florida Institute of Technology, Melbourne, USA
V. Bhopatkar, M. Hohlmann, H. Kalakhety, D. Mareskas-palcek, T. Roy, F. Yumiceva
University of Illinois at Chicago (UIC), Chicago, USA
M.R. Adams, L. Apanasevich, D. Berry, R.R. Betts, I. Bucinskaite, R. Cavanaugh, O. Evdokimov,L. Gauthier, C.E. Gerber, D.J. Hofman, P. Kurt, C. O’Brien, I.D. Sandoval Gonzalez,C. Silkworth, P. Turner, N. Varelas, Z. Wu, M. Zakaria
The University of Iowa, Iowa City, USA
B. Bilki , W. Clarida, K. Dilsiz, R.P. Gandrajula, M. Haytmyradov, V. Khristenko, J.-P. Merlo,H. Mermerkaya , A. Mestvirishvili, A. Moeller, J. Nachtman, H. Ogul, Y. Onel, F. Ozok ,A. Penzo, S. Sen, C. Snyder, P. Tan, E. Tiras, J. Wetzel, K. Yi Johns Hopkins University, Baltimore, USA
I. Anderson, B.A. Barnett, B. Blumenfeld, D. Fehling, L. Feng, A.V. Gritsan, P. Maksimovic,C. Martin, K. Nash, M. Osherson, M. Swartz, M. Xiao, Y. Xin
The University of Kansas, Lawrence, USA
P. Baringer, A. Bean, G. Benelli, C. Bruner, J. Gray, R.P. Kenny III, D. Majumder, M. Malek,M. Murray, D. Noonan, S. Sanders, R. Stringer, Q. Wang, J.S. Wood
Kansas State University, Manhattan, USA
I. Chakaberia, A. Ivanov, K. Kaadze, S. Khalil, M. Makouski, Y. Maravin, L.K. Saini,N. Skhirtladze, I. Svintradze
Lawrence Livermore National Laboratory, Livermore, USA
D. Lange, F. Rebassoo, D. Wright
University of Maryland, College Park, USA
C. Anelli, A. Baden, O. Baron, A. Belloni, B. Calvert, S.C. Eno, J.A. Gomez, N.J. Hadley,S. Jabeen, R.G. Kellogg, T. Kolberg, Y. Lu, A.C. Mignerey, K. Pedro, Y.H. Shin, A. Skuja,M.B. Tonjes, S.C. Tonwar
Massachusetts Institute of Technology, Cambridge, USA
A. Apyan, R. Barbieri, A. Baty, K. Bierwagen, S. Brandt, W. Busza, I.A. Cali, L. Di Matteo,G. Gomez Ceballos, M. Goncharov, D. Gulhan, M. Klute, Y.S. Lai, Y.-J. Lee, A. Levin,P.D. Luckey, C. Mcginn, X. Niu, C. Paus, D. Ralph, C. Roland, G. Roland, G.S.F. Stephans,K. Sumorok, M. Varma, D. Velicanu, J. Veverka, J. Wang, T.W. Wang, B. Wyslouch, M. Yang,V. Zhukova
University of Minnesota, Minneapolis, USA
B. Dahmes, A. Finkel, A. Gude, S.C. Kao, K. Klapoetke, Y. Kubota, J. Mans, S. Nourbakhsh,R. Rusack, N. Tambe, J. Turkewitz
University of Mississippi, Oxford, USA
J.G. Acosta, S. Oliveros
University of Nebraska-Lincoln, Lincoln, USA
E. Avdeeva, K. Bloom, S. Bose, D.R. Claes, A. Dominguez, C. Fangmeier, R. Gonzalez Suarez, R. Kamalieddin, J. Keller, D. Knowlton, I. Kravchenko, J. Lazo-Flores, F. Meier, J. Monroy,F. Ratnikov, J.E. Siado, G.R. Snow
State University of New York at Buffalo, Buffalo, USA
M. Alyari, J. Dolen, J. George, A. Godshalk, I. Iashvili, J. Kaisen, A. Kharchilava, A. Kumar,S. Rappoccio
Northeastern University, Boston, USA
G. Alverson, E. Barberis, D. Baumgartel, M. Chasco, A. Hortiangtham, A. Massironi,D.M. Morse, D. Nash, T. Orimoto, R. Teixeira De Lima, D. Trocino, R.-J. Wang, D. Wood,J. Zhang
Northwestern University, Evanston, USA
K.A. Hahn, A. Kubik, N. Mucia, N. Odell, B. Pollack, A. Pozdnyakov, M. Schmitt, S. Stoynev,K. Sung, M. Trovato, M. Velasco, S. Won
University of Notre Dame, Notre Dame, USA
A. Brinkerhoff, N. Dev, M. Hildreth, C. Jessop, D.J. Karmgard, N. Kellams, K. Lannon, S. Lynch,N. Marinelli, F. Meng, C. Mueller, Y. Musienko , T. Pearson, M. Planer, R. Ruchti, G. Smith,N. Valls, M. Wayne, M. Wolf, A. Woodard The Ohio State University, Columbus, USA
L. Antonelli, J. Brinson, B. Bylsma, L.S. Durkin, S. Flowers, A. Hart, C. Hill, R. Hughes,K. Kotov, T.Y. Ling, B. Liu, W. Luo, D. Puigh, M. Rodenburg, B.L. Winer, H.W. Wulsin
Princeton University, Princeton, USA
O. Driga, P. Elmer, J. Hardenbrook, P. Hebda, S.A. Koay, P. Lujan, D. Marlow, T. Medvedeva,M. Mooney, J. Olsen, P. Pirou´e, X. Quan, H. Saka, D. Stickland, C. Tully, J.S. Werner, A. Zuranski
Purdue University, West Lafayette, USA
V.E. Barnes, D. Benedetti, D. Bortoletto, L. Gutay, M.K. Jha, M. Jones, K. Jung, M. Kress,N. Leonardo, D.H. Miller, N. Neumeister, F. Primavera, B.C. Radburn-Smith, X. Shi, I. Shipsey,D. Silvers, J. Sun, A. Svyatkovskiy, F. Wang, W. Xie, L. Xu, J. Zablocki
Purdue University Calumet, Hammond, USA
N. Parashar, J. Stupak
Rice University, Houston, USA
A. Adair, B. Akgun, Z. Chen, K.M. Ecklund, F.J.M. Geurts, W. Li, B. Michlin, M. Northup,B.P. Padley, R. Redjimi, J. Roberts, J. Rorie, Z. Tu, J. Zabel
University of Rochester, Rochester, USA
B. Betchart, A. Bodek, P. de Barbaro, R. Demina, Y. Eshaq, T. Ferbel, M. Galanti, A. Garcia-Bellido, P. Goldenzweig, J. Han, A. Harel, O. Hindrichs, A. Khukhunaishvili, G. Petrillo,M. Verzetti, D. Vishnevskiy
The Rockefeller University, New York, USA
L. Demortier
Rutgers, 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, E. Hughes, S. Kaplan,R. Kunnawalkam Elayavalli, A. Lath, S. Panwalkar, M. Park, S. Salur, S. Schnetzer, D. Sheffield,S. Somalwar, R. Stone, S. Thomas, P. Thomassen, M. Walker A The CMS Collaboration
University of Tennessee, Knoxville, USA
M. Foerster, K. Rose, S. Spanier, A. York
Texas A&M University, College Station, USA
O. Bouhali , A. Castaneda Hernandez, M. Dalchenko, M. De Mattia, A. Delgado, S. Dildick,R. Eusebi, W. Flanagan, J. Gilmore, T. Kamon , V. Krutelyov, R. Montalvo, R. Mueller,I. Osipenkov, Y. Pakhotin, R. Patel, A. Perloff, J. Roe, A. Rose, A. Safonov, I. Suarez, A. Tatarinov,K.A. Ulmer Texas Tech University, Lubbock, USA
N. Akchurin, C. Cowden, J. Damgov, C. Dragoiu, P.R. Dudero, J. Faulkner, K. Kovitanggoon,S. Kunori, K. Lamichhane, S.W. Lee, T. Libeiro, S. Undleeb, I. Volobouev
Vanderbilt University, Nashville, USA
E. Appelt, A.G. Delannoy, S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, Y. Mao,A. Melo, P. Sheldon, B. Snook, S. Tuo, J. Velkovska, Q. Xu
University of Virginia, Charlottesville, USA
M.W. Arenton, S. Boutle, B. Cox, B. Francis, J. Goodell, R. Hirosky, A. Ledovskoy, H. Li, C. Lin,C. Neu, E. Wolfe, J. Wood, F. Xia
Wayne State University, Detroit, USA
C. Clarke, R. Harr, P.E. Karchin, C. Kottachchi Kankanamge Don, P. Lamichhane, J. Sturdy
University of Wisconsin, Madison, USA
D.A. Belknap, D. Carlsmith, M. Cepeda, A. Christian, S. Dasu, L. Dodd, S. Duric, E. Friis,R. Hall-Wilton, M. Herndon, A. Herv´e, P. Klabbers, A. Lanaro, A. Levine, K. Long, R. Loveless,A. Mohapatra, I. Ojalvo, T. Perry, G.A. Pierro, G. Polese, I. Ross, T. Ruggles, T. Sarangi, A. Savin,N. Smith, W.H. Smith, D. Taylor, N. Woods † : Deceased1: Also at Vienna University of Technology, Vienna, Austria2: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland3: Also at Institut Pluridisciplinaire Hubert Curien, Universit´e de Strasbourg, Universit´e deHaute Alsace Mulhouse, CNRS/IN2P3, Strasbourg, France4: Also at National Institute of Chemical Physics and Biophysics, Tallinn, Estonia5: Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University,Moscow, Russia6: Also at Universidade Estadual de Campinas, Campinas, Brazil7: Also at Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France8: Also at Universit´e Libre de Bruxelles, Bruxelles, Belgium9: Also at Joint Institute for Nuclear Research, Dubna, Russia10: Also at Ain Shams University, Cairo, Egypt11: Now at British University in Egypt, Cairo, Egypt12: Now at Helwan University, Cairo, Egypt13: Also at Cairo University, Cairo, Egypt14: Now at Fayoum University, El-Fayoum, Egypt15: Also at Universit´e de Haute Alsace, Mulhouse, France16: Also at Brandenburg University of Technology, Cottbus, Germany17: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary18: Also at E ¨otv ¨os Lor´and University, Budapest, Hungary19: Also at University of Debrecen, Debrecen, Hungary20: Also at Wigner Research Centre for Physics, Budapest, Hungary9