Search for supersymmetry in the vector-boson fusion topology in proton-proton collisions at \( \sqrt{s}=8 \) TeV

Journal of High Energy Physics, Nov 2015

Abstract The first search for supersymmetry in the vector-boson fusion topology is presented. The search targets final states with at least two leptons, large missing transverse momentum, and two jets with a large separation in rapidity. The data sample corresponds to an integrated luminosity of 19.7 fb−1 of proton-proton collisions at \( \sqrt{s}=8 \) TeV collected with the CMS detector at the CERN LHC. The observed dijet invariant mass spectrum is found to be consistent with the expected standard model prediction. Upper limits are set on the cross sections for chargino and neutralino production with two associated jets, assuming the supersymmetric partner of the τ lepton to be the lightest slepton and the lightest slepton to be lighter than the charginos. For a so-called compressed-mass-spectrum scenario in which the mass difference between the lightest supersymmetric particle \( {\tilde{\chi}}_1^0 \) and the next lightest, mass-degenerate, gaugino particles \( {\tilde{\chi}}_2^0 \) and \( {\tilde{\chi}}_1^{\pm } \) is 50 GeV, a mass lower limit of 170 GeV is set for these latter two particles. Open image in new window

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Search for supersymmetry in the vector-boson fusion topology in proton-proton collisions at \( \sqrt{s}=8 \) TeV

HJE Search for supersymmetry in the vector-boson fusion 0 s = 8 TeV collected 1 61: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences The rst search for supersymmetry in the vector-boson fusion topology is presented. The search targets nal states with at least two leptons, large missing transverse to an integrated luminosity of 19.7 fb 1 of proton-proton collisions at p momentum, and two jets with a large separation in rapidity. The data sample corresponds with the CMS detector at the CERN LHC. The observed dijet invariant mass spectrum is found to be consistent with the expected standard model prediction. Upper limits are set on the cross sections for chargino and neutralino production with two associated jets, assuming the supersymmetric partner of the lepton to be the lightest slepton and the limit of 170 GeV is set for these latter two particles. lightest slepton to be lighter than the charginos. For a so-called compressed-mass-spectrum scenario in which the mass di erence between the lightest supersymmetric particle e10 and the next lightest, mass-degenerate, gaugino particles e20 and e1 is 50 GeV, a mass lower Supersymmetry; Hadron-Hadron Scattering - 8 TeV p The CMS collaboration 1 Introduction CMS detector 2 3 4 5 6 7 8 9 Object reconstruction and identi cation Signal and background samples Event selection Background estimation Systematic uncertainties Results and interpretation Summary The CMS collaboration 1 Introduction and is a dark matter candidate. With the successful operation of the CERN LHC, numerous results placing constraints on extensions to the standard model (SM) have been presented by the ATLAS and CMS experiments. In particular, in models of supersymmetry (SUSY) [1{7], limits in excess of 1 TeV have been placed on the masses of the strongly produced gluinos and rst- and secondgeneration squarks [8{15]. In contrast, mass limits on the weakly produced charginos ( ei ) and neutralinos ( ei0), with much smaller production cross sections, are much less severe. The limits for charginos and neutralinos are especially weak in so-called compressed-massspectrum scenarios, in which the mass of the lightest supersymmetric particle (LSP) is only slightly less than the masses of other SUSY states. The chargino-neutralino sector plays a crucial role in the connection between dark matter and SUSY: in SUSY models with R-parity [16] conservation, the lightest neutralino e10 often takes the role of the LSP Previous LHC searches [17, 18] for electroweak chargino and neutralino production have focused on nal states with one or more leptons (`) and missing transverse momentum (p~Tmiss), e.g., e1 e20 pair production followed by e1 ! ` e10 and e2 ! `` e01, where 0 is the lightest (next-to-lightest) chargino (neutralino), and where the LSP e10 is presumed to escape without detection leading to signi cant pmiss. However, these searches exhibit e1 ( e02 ) limited sensitivity in cases where the e1 and e20 are nearly mass degenerate with the e1 0 . The mass di erence m = m e1 me01 is a crucial parameter dictating the sensitivity of the analysis. While the exclusion limits in refs. [17, 18] can be as large as m < 720 GeV for a massless e01, they weaken to only also exhibit limited sensitivity to models with SUSY particles that decay predominantly to leptons, even for LSP masses near zero, due to the larger backgrounds associated with 100 GeV for m < 50 GeV. The current searches e1 -lepton reconstruction compared to electrons or muons. Electroweak SUSY particles can be pair produced in association with two jets in pure electroweak processes in the vector-boson fusion (VBF) topology [19], which is characterized by the presence of two forward jets (i.e. jets near the beam axis), in opposite hemispheres, leading to a large dijet invariant mass (mjj ). Figure 1 shows the Feynman diagrams for two of the possible VBF production processes: chargino-neutralino and chargino-chargino production. A search in the VBF topology o ers a new and complementary means to directly probe the electroweak sector of SUSY, especially in compressed-mass-spectrum scenarios [20]. It targets unexplored regions of SUSY parameter space, where other searches have limited sensitivity. It di ers fundamentally from the conventional direct electroweak SUSY searches mentioned above in that it uses the presence of jets with large transverse momenta (pT) to suppress SM background. In this regard, it resembles searches for strongly produced SUSY particles. However, unlike these latter studies, which present searches for the indirect production of charginos and neutralinos through squark or gluino decay chains [10{12], the VBF search does not require the production of squarks or gluinos, whose masses might be too large to allow production at the LHC. In this paper, we present a search for the electroweak production of SUSY particles in the VBF topology. The data, corresponding to an integrated luminosity of 19.7 fb 1 of proton-proton collisions at a centre-of-mass energy of p s = 8 TeV, were collected with T the CMS detector in 2012. Besides the two oppositely directed forward jets (j) that de ne the VBF con guration, the search requires the presence of at least two leptons (e; ; or ) and large pmiss. The events are classi ed into one of eight nal states depending on the dilepton content and charges e jj, jj, hjj, and h hjj, where h denotes a hadronically decaying lepton and where we di erentiate between nal states with same-sign (SS) { 2 { and opposite-sign (OS) dilepton pairs. The dijet invariant mass distribution mjj is used to search for the SUSY signal. Stringent requirements are placed on pmiss and on the kinematic properties of the VBF dijet system to suppress SM background. In particular, the R-parity conserving SUSY models we examine predict much higher average dijet pT than is typical for SM processes such as VBF Higgs boson production [21], allowing us to suppress the background by a factor of 102{104, depending on the background process. used to normalize the predicted rates to the data. The paper is organized as follows. The CMS detector is described in section 2. The reconstruction of electrons, muons, h leptons, jets, and pmiss is presented in section 3. The T dominant backgrounds and their simulated samples are discussed in section 4, followed by the description of the event selection in section 5 and the background estimation in section 6. Systematic uncertainties are summarized in section 7, and the results are presented in section 8. Section 9 contains a summary. 2 CMS detector The central feature of the CMS apparatus is a superconducting solenoid of 6 m internal diameter, providing a magnetic eld of 3.8 T. Located within the solenoid volume are a silicon pixel and strip tracker, a lead tungstate electromagnetic calorimeter (ECAL), and a brass and scintillator hadron calorimeter. Muons are measured in gas-ionisation detectors embedded in the steel ux-return yoke outside the solenoid. Extensive forward calorimetry complements the coverage provided by the barrel and endcap detectors. Forward hadron calorimeters on each side of the CMS interaction point cover the very forward angles of CMS, in the pseudorapidity range 3:0 < j j < 5:0. The inner tracker measures charged tracks with j j < 2:5 and provides an impact parameter resolution of 15 m and a transverse momentum resolution of about 1.5% for 100 GeV charged particles. Events are selected with a rst-level trigger made of a system of fast electronics, and a high-level trigger that consists of a farm of commercial CPUs running a version of the o ine reconstruction optimized for fast processing. A detailed description of the CMS detector, along with a de nition of the coordinate system and relevant kinematic variables, can be found in ref. [22]. 3 Object reconstruction and identi cation The missing transverse momentum vector p~miss is de ned as the projection on the plane T perpendicular to the beam axis of the negative vector sum of the momenta of all recon{ 3 { structed particles in an event. Its magnitude is referred to as pmiss. The jets and pmiss are reconstructed with the particle- ow algorithm [23, 24]. The anti-kT clustering algorithm [25] with a distance parameter of 0.5 is used for jet clustering. Jets are required to satisfy identi cation criteria designed to reject particles from multiple proton-proton interactions (pileup) and anomalous behavior from the calorimeters. For jets with pT > 30 GeV and j j < 2:5 (2:5 < j j < 5:0), the reconstruction-plus-identi cation e ciency is 99% (95%), while 90{95% (60%) of pileup jets are rejected [26]. The jet energy scale and resolution are calibrated through correction factors that depend on the pT and of the jet [27]. Jets originating from the hadronisation of bottom quarks (b quark jets) are identi ed using the loose working point of the combined secondary vertex (CSV) algorithm [28], which HJEP1(205)89 exploits observables related to the long lifetime of b hadrons. For jets with pT > 20 GeV and j j < 2:4, the probability of correctly identifying a b quark jet is 85%, while the probability of misidentifying a jet originating from a light quark or gluon as a b quark jet is Muons are reconstructed [30] using the inner silicon tracker and muon detectors. QualR = p ( ity requirements based on the minimum number of hits in the silicon tracker, pixel detector, and muon detectors are applied to suppress backgrounds from decays-in- ight and hadron shower remnants that reach the muon system. Electrons are reconstructed [31] by combining tracks produced by the Gaussian-sum lter algorithm with ECAL clusters. Requirements on the track quality, the shape of the energy deposits in the ECAL, and the compatibility of the measurements from the tracker and the ECAL are imposed to distinguish prompt electrons from charged pions and from electrons produced by photon conversions. The electron and muon reconstruction e ciencies are > 99% for pT > 10 GeV. The electron and muon candidates are required to satisfy isolation criteria in order to reject non-prompt leptons from the hadronisation process. Isolation is de ned as the scalar sum of the pT values of reconstructed charged and neutral particles within a cone of radius )2 + ( )2 = 0:4 around the lepton-candidate track, divided by the pT of the lepton candidate. A correction is applied to the isolation variable to account for the e ects of additional interactions. For charged particles, only tracks associated with the primary vertex are included in the isolation sums. The primary vertex is the reconstructed vertex with the largest sum of charged-track p 2T values associated to it. For neutral particles, a correction is applied by subtracting the energy deposited in the isolation cone by charged particles not associated with the primary vertex, multiplied by a factor of 0.5. This factor corresponds approximately to the ratio of neutral to charged hadron production in the hadronisation process of pileup interactions. In both cases, the contribution from the electron or muon candidate is removed from the sum and the value of the isolation variable is required to be 0.2 or less. The muon identi cation-plus-isolation e ciency is 96% for muons with pT > 15 GeV and j j < 2:1. The rate at which pions undergoing ! is 10 3 for pions with pT > 10 GeV and j j < 2:1. The electron identi cation-plus-isolation e ciency is 85% (80%) for electrons with pT > 30 GeV in the barrel (endcap) region [31]. The j ! e misidenti cation rate is 5 10 3 for jets with pT > 10 GeV and j j < 2:1. Hadronic decays of leptons are reconstructed and identi ed using the hadrons-plusstrips algorithm [32], which is designed to optimize the performance of the h reconstruction decay are misidenti ed as muons { 4 { Selection pT( )[GeV] pT(`e= )[GeV] pT( h)[GeV] j (` ;e; h )j Njbe-ttsag T pmiss[GeV] pT(jets) j (jets)j j (jets)j jj and e jj channels are presented in one column (`e= jj) as they are similar. The symbol `e; ; h means that the lepton could be an electron, a muon, or a h lepton. by considering speci c h decay modes. To suppress backgrounds in which light-quark or gluon jets can mimic h decays, a h candidate is required to be spatially isolated from other energy deposits in the event. The isolation variable is calculated using a multivariate boosted-decision-tree technique by forming rings of radius R around the direction of the h candidate, using the energy deposits of particles not considered in the reconstruction of the h decay mode. Additionally, h candidates are required to be distinguishable from electrons and muons in the event by using dedicated criteria based on the consistency among the measurements in the tracker, calorimeters, and muon detectors. The identi cation and isolation e ciency is 55{65% for a h lepton with pT > 20 GeV and j j < 2:1, depending on the pT and values of the h candidate. The rate at which jets are misidenti ed as a h lepton is 1{5%, depending on the pT and values of the h candidate. The event selection criteria used in each search channel are summarized in section 5 (see table 1). 4 Signal and background samples The composition of SM background events depends on the nal state and, in particular, the number of h candidates. The most important sources of background arise from the production of W or Z bosons in association with jets (W=Z+jets), and from tt, diboson (VV: WW, WZ, ZZ), and Quantum ChromoDynamics (QCD) multijet events. The W+jets events are characterized by an isolated lepton from the decay of the W boson and uncorrelated jets misidenti ed as an e, , or h . Background from W+jets events is especially pertinent for nal states with one h candidate. Background from tt events usually contains one or two tagged b quark jets, in addition to a genuine isolated e, , or h . Background from diboson events contains genuine, isolated leptons when the bosons decay leptonically, and jets that are misidenti ed as a h lepton when they decay hadron{ 5 { ically. The QCD background is characterized by jets that are misidenti ed as an e, , or h lepton. The QCD multijet process is an appreciable background only for the h h nal states. There are negligible contributions from background processes such as single-top and VBF production of a Higgs or Z boson. These background yields are taken from simulation. Simulated samples of signal and background events are generated using Monte Carlo (MC) event generators. The signal event samples are generated with the MadGraph program (v5.1.5) [33], considering pair production of e1 and e20 gauginos ( e1 e1 , e1 e1 , 0 0) with two associated partons. The signal events are generated requiring a j > 4:2 between the two partons, with pT > 30 GeV for each parton. ized to next-to-next-to-leading-order using the results from the fewz v2.1 [37] generator. The diboson background processes are normalized to next-to-leading-order using the mcfm v5.8 [38] generator, while the VBF Z boson events are normalized to next-to-leading order using the VBFNLO (v2.6) [39, 40] program. The single-top and VBF Higgs boson background yields are taken from the powheg program, where the next-to-leading order e ects are incorporated. Signal cross sections are calculated at leading order using the MadGraph generator. All MC samples incorporate the CTEQ6L1 [41] or CTEQ6M [42] parton distribution functions (PDF). The corresponding evaluation of uncertainties in the signal cross sections is discussed in section 7. The range of signal cross sections is 50{1 fb for e02 = e1 masses of 100{400 GeV. The powheg and MadGraph generators are interfaced with the pythia (v6.4.22) [43] program, which is used to describe the parton shower and hadronisation processes. The decays of leptons are described using the tauola (27.1215) [ 44 ] program. The background samples are processed with a detailed simulation of the CMS apparatus using the Geant4 package [45], while the response for signal samples is modeled with the CMS fast simulation program [ 46 ]. For the signal acceptance and mjj shapes based on the fast simulation, the di erences with respect to the Geant4-based results are found to be small (< 5%). Corrections are applied to account for the di erences. For all MC samples, multiple proton-proton interactions are superimposed on the primary collision process, and events are reweighted such that the distribution of reconstructed collision vertices matches that in data. The distribution of the number of pileup interactions per event has a mean of 21 and a root-mean-square of 5.5. 5 Event selection A single-muon trigger [30] with a pT threshold of 24 GeV is used for the hjj nal states. The h hjj channels use a double- h trigger [47] that requires pT > 35 GeV for each h. A requirement on pseudorapidity (j j < 2:1) is applied to select high quality and well-isolated leptons (e; ; h) within the tracker acceptance. The pT thresholds de ning the search regions are chosen to achieve a trigger e ciency greater than 90%. For nal states with at least one muon ( jj; e jj; hjj), events are selected by requiring a muon with pT > 30 GeV. For the h h channels, both h candidates are required to satisfy pT > 45 GeV. The following requirements are referred to as the \central selection", and are applied to all nal states. Pairs of leptons are required to be separated by R > 0:3 and to originate from the primary vertex. All channels require exactly two leptons satisfying selection criteria. Events with an e or pmiss > 30 GeV is used for the h hjj T T are required to have pmiss > 75 GeV, while a requirement nal state to compensate for the loss in acceptance due to the higher pT threshold of h leptons while maintaining similar background rejection. Background from tt events is reduced by removing events in which any jet has pT > 20 GeV, is separated from the leptons by R > 0:3, and is identi ed as b-quark jet using the loose working point of the CSV algorithm. The \VBF selection" refers to the requirement of at least two jets in opposite hemispheres ( 1 2 < 0) with large separation (j j > 4:2). Events are selected with at least two jets with pT > 50 GeV and pseudorapidity j j < 5:0. The jj search region has a lower background rate with respect to other nal states, which makes it possible to relax the jet pT requirement to 30 GeV to increase the signal acceptance. The event selection criteria with pT > 30 GeV are referred to as \Loose". The event selection criteria with pT > 50 GeV are referred to as \Tight". Selected events are required to have a dijet candidate with mjj > 250 GeV. The signal region (SR) is de ned as the events that satisfy the central and VBF selection criteria. A summary of the event selection criteria used in each channel is presented in table 1. 6 Background estimation The general methodology used to evaluate the background is the same for all nal states. We isolate various control regions (CR) to measure the VBF e ciencies (the probability for a given background component to satisfy the VBF selection criteria) and mjj shapes from data, validate the modeling of the central selection criteria, and determine a correction factor to account for the selection e ciency by assessing the level of agreement between data and simulation. For each nal state, the same trigger is used for the CRs as for the corresponding SR. The VBF e ciency, measured in a CR satisfying only the central selection, is de ned as the fraction of events in the CR additionally passing the VBF event selection criteria. The tt, W+jets, and VV backgrounds are evaluated using the following equation: NBprGed(mjj ) = NBMGC(central) SFBCGR1(central) CVRBF2(mjj ); (6.1) where NBprGed is the predicted background yield in the signal region, NBMGC(central) is the rate predicted by the \BG" simulation (with BG = tt, W+jets, or VV) for the central { 7 { selection, SFBCGR1(central) is the data-to-simulation correction factor for the central region, given by the ratio of data to the \BG" simulation in control region CR1, and CVRB2F is the VBF e ciency, determined as a function of mjj in data control sample CR2 or, in the case of VV events, from simulation. The event selection criteria used to de ne the CR must not bias the mjj distribution. This is veri ed, in simulation and data, by comparing the mjj distributions with and without the selection criteria used to de ne the CR. The background estimation technique used to measure the VBF e ciency and mjj shape from data is performed with simulated events to test the closure, where closure refers to the ability of the method to predict the correct background yields when using simulation in place of data. The closure tests demonstrate that the background determination techniques, described in detail below, reproduce the expected background distributions in both rate and shape to within the statistical uncertainties. The di erence between the nominal MC background yields and the yields predicted from the closure test are added in quadrature with the statistical uncertainties of the prediction to de ne a systematic uncertainty. Simulated samples are further used to verify that the composition of objects erroneously identi ed as leptons, and their kinematic properties, are similar between the CRs and SR, and thus that the scale factors SFBCGR1(central) are unbiased. A variety of generators (MadGraph, pythia, and powheg) are used for this purpose to establish the robustness of this expectation. The production of tt events is an important source of background for the hjj nal states. Control regions enriched with tt events are obtained by requiring the presence of at least one reconstructed b-tagged jet with pT > 20 GeV. The tt purity of the resulting data CR1s depends on the nal state, ranging from 76 to 99%. The contributions of backgrounds other than tt events are subtracted from the data CR1s using simulation. The scale factors SFtCt R1 are then determined. The uncertainties related to the subtraction procedure are propagated to the scale factors. For the OS channels, the scale factors are consistent with unity to within 3%. The tt events with OS lepton pairs arise from genuine isolated leptons produced through leptonic W boson decay, and are well modeled by the simulation. On the other hand, tt events with SS lepton pairs mostly contain a lepton candidate that is a misidenti ed hadron or jet, which is more di cult to accurately simulate. The scale factors for SS events range from 1.2 to 1.5, with statistical uncertainties up to 25%. Since the fraction of lepton candidates that are in fact a misidenti ed hadron or jet varies according to the nal state, the scale factors are determined independently for each channel. In contrast, the VBF e ciency for a given combination of lepton avors does not depend on the charge state, and thus each pair of nal states with the same avor combination shares the same VBF e ciency value. The VBF e ciency is measured in data CR2 control samples obtained by additionally removing the charge requirement on the lepton pair and relaxing or inverting the lepton isolation requirement (isolation sidebands) in order to enhance the purity and statistical precision of the CR2s. Figure 2 shows the \Tight" and \Loose" VBF e ciencies measured from data, as a function of mjj , for events in the tt CR2s of the jj nal states. The VBF e ciencies CVRB2F range from 0.02 to 0.003, with relative uncertainties below 11% for mjj > 250 GeV. We verify that the b tagging, charge, and isolation requirements used to obtain the CR1 and CR2 samples do not bias the mjj shape or the kinematic distributions of the leptons. { 8 { jj nal state, for the \Loose" (pT > 30 GeV) and \Tight" p 2pTmisspT[1 cos( The production of W+jets events presents an important source of background only for the hjj search channels. Samples enriched in W+jets events, with about 70% purity according to simulation, are obtained by requiring the transverse mass mT ;p~Tmiss )] between p~miss and the muon transverse momentum p T satisfy 40 < mT < 110 GeV. The correction factor SFWCR+1jets is determined to be 0:90 where the uncertainty is a combination of the statistical uncertainty from data, the statistical uncertainty from simulation, and the systematic uncertainty associated with the subtraction of the non-W+jets backgrounds from the data control sample. The lepton and h isolation sidebands are used to obtain W+jets-enriched CR2 samples, with negligible expected signal contributions, not only to measure the VBF e ciencies and mjj shape from data, but also to provide further validation of the SFWCR+1jets correction factor. To validate the correction factor, the W+jets rate in the h isolation sideband is scaled by 0:90 0:11, and agreement between the data and the corrected W+jets prediction from simulation is observed. The VBF e ciency determined from the CR2 control sample is measured to be 1% for mjj > 250 GeV. Agreement between the VBF e ciencies of Z+jets and W+jets T to 0:11, processes is observed in the hjj channel. The background from VV events is signi cant for nal states containing only electrons T and muons, comprising up to 10% of the total SM background in the OS channels, and up to 40% in the SS channels. The diboson background is suppressed in the h nal states because of the lower average pT of the visible -lepton decay products. Diboson events have genuine isolated leptons and pmiss from neutrinos and can satisfy the VBF selection when produced in association with jets arising from initial-state radiation or from a SM VBF process. We select diboson-enriched CR1 samples (97% purity) by requiring at least { 9 { three leptons and inverting the pTmiss requirement (pTmiss < 75 GeV). The level of agreement between data and simulation for the event rates, VBF e ciencies, and mjj shapes are found to be the same for all types of VV processes in the CR1 samples. The data-tosimulation correction factor is SFVCVR1 = 1:12 0:06. The mjj distributions, following the VBF selections, are consistent between data and simulation. Therefore, the VBF e ciency is taken directly from simulation. uated using the following relation: The Z+jets background is important for all OS nal states. This background is evalNZp+rejdets(mjj ) = NZM+Cjets(central) SFZC+Rj1ets(central) SFpCTmRis3s CVRBF1(mjj ); (6.2) where NZM+Cjets, SFZC+Rj1ets, and CVRB1F have the same meaning as the analogous quantities in eq. (6.1) (with BG = Z+jets), and the SFpCmRis3s term is described below. Control samples T (CR1) dominated by Z ! ``+jets events with ` = e; requiring pmiss < 75 GeV and an OS lepton pair mass m`` consistent with the Z boson T (60 < m`` < 120 GeV). The rates and kinematic distributions of leptons in these control samples are consistent between the data and simulation. These control samples are used to determine both the SFZC+Rj1ets correction factors and the CVRBF1 terms, in the same manner as described above for the analogous quantities. The correction factors are unity to within 1%. Figure 2 shows the \Tight" and \Loose" VBF e ciencies measured from data, as a (> 98% purity) are selected by function of mjj , for events in the to 10 5. The measured jj channel. The VBF e ciencies range from 10 3 CVRBF1 terms agree with the results from simulation within 23%, T which is taken as a systematic uncertainty both for the background prediction and for the VBF e ciency in simulated signal events. Additional orthogonal Z+jets control samples (CR3) are selected with similar selection criteria as used for the signal, maintaining the pmiss requirement (>75 GeV) and inverting the VBF selection (i.e. at least one of the VBF selection requirements is not satis ed: 2 jets, jet pT, j j, or 1 2). These control samples the data and simulation for high-pTmiss events. The factors are 1:03 are used to determine the correction factors SFpCmRis3s , which account for di erences between T the h (light-lepton avor) channels. This mismodeling arises from the mismeasurement of pT for jets and leptons. High-purity samples of Z ! ! ` h events, from which the SFZC+Rj1ets terms can be evaluated for the search channels with at least one h, are obtained by removing the VBF selection and requiring mT(`; pTmiss) < 15 GeV. The VBF e ciency for Z ! processes is obtained from data using the Z ! ``+jets control samples described above. +jets The QCD multijet background is negligible for all nal states except the h hjj channel. To estimate the QCD multijet contribution to this channel, we select a QCD-dominated (> 90% purity) CR1 by requiring two h candidates with relaxed isolation requirements. In addition, we require that the CR1 events contain an SS h h pair. The SS signal region is thus included in CR1, but the potential impact of signal events is found to be negligible. The QCD multijet background in the OS h h channel is estimated by: NQprCeDd(mjj ) = NQCCRD1(central) ROS=SS CVRB2F(mjj ); (6.3) where NQCCRD1(central) is the yield observed in the CR1 sample with no VBF requirements, following subtraction of the non-QCD component from CR1 using simulation. The OSto-SS ratio ROS=SS is obtained from a low-pTmiss (pTmiss < 30 GeV) region after subtraction of the non-QCD contributions: we nd ROS=SS = 1:33 0:03. Besides its use in the background determination procedure [eq. (6.3)], the measured result for ROS=SS is used to provide a cross-check: we use it to extrapolate from an SS to an OS control region, both selected requiring pmiss < 30 GeV and two non-isolated h candidates. The obtained T prediction for the rate of non-isolated OS h leptons is in agreement with the observation. Finally, the e ciency CVRBF2 is measured in exclusive sidebands ful lling inverted h isolation criteria. It is estimated as the rate of events with two non-isolated h candidates plus two jets satisfying the VBF requirements divided by the rate of events with two nonisolated h candidates without any additional jet requirements. The measured e ciency is VBF = 0:35% 0:08% (stat) 0:06% (syst). The QCD multijet background in the SS h hjj channel is estimated using the following relation: NQprCeDd = N QfaCilD-VBF 1 VBF non-iso h non-iso h : VBF (6.4) Here, N QfaCilD-VBF is the observed yield in data, with non-QCD background from simulation subtracted, in an SS h h control sample requiring at least two jets not associated with one of the h candidates to fail any of the j j , 1 2, or mjj requirements. The VBF e ciency non-iso h ( VBF for short) is measured in six exclusive h isolation sidebands, without a pTmiss VBF requirement and at least two jets. The validity of the method is demonstrated in data by the agreement that is observed, within statistical uncertainties, of these six independent measurements of VBF. The six corresponding control samples in simulation are used to test the stability of VBF as a function of pTmiss and the h isolation requirements. For this purpose, the probability for a single jet to be misidenti ed as a h lepton is determined from simulation. The misidenti cation rates depend on the jet pT and are used to determine an overall event weight by randomly selecting two jets in the event to represent the h leptons. The VBF e ciencies in simulation are calculated from these weighted samples and demonstrate consistency with respect to the di erent pmiss and h isolation requirements T at the level of 19%, which is assigned as a systematic uncertainty in the background prediction. The VBF e ciency for mjj > 250 GeV is VBF = 6:7% 0:5% (stat)+10::25%% (syst). 7 Systematic uncertainties The main contributions to the total systematic uncertainty in the background predictions arise from the closure tests and from the statistical uncertainties associated with the data control regions used to determine the CVRBF, SFBCGR1(central), and ROS=SS factors. The relative systematic uncertainties in SFBCGR1 and ROS=SS related to the statistical precision in the CRs range between 1 and 25%, depending on the background component and search channel. For mjj > 250 GeV, the statistical uncertainties in CVRBF lie between 3 and 21%, while the systematic uncertainties evaluated from the closure tests and cross-checks with data range from 2 to 20%. For the background CVRBF, we assign no uncertainty due to the jet energy correction, as the mjj distributions are taken directly from the data control regions. T momentum scales, pmiss scale, and trigger e ciency. Less signi cant contributions to the systematic uncertainties arise from contamination by non-targeted background sources to the CRs used to measure CVRBF, and from the uncertainties in SFBCGR1(central) due to the lepton identi cation e ciency, lepton energy and The e ciencies for the electron and muon trigger, reconstruction, identi cation, and isolation requirements are measured with the \tag-and-probe" method [30, 31] with a resulting uncertainty of 2%. The h trigger and identi cation-plus-isolation e ciencies are measured from a t to the Z ! ! h visible mass distribution in a sample HJEP1(205)89 selected with a single-muon trigger, leading to a relative uncertainty of 4% and 6% per h candidate, respectively [47]. The pTmiss scale uncertainties contribute via the jet energy scale (2{10% depending on and pT) and unclustered energy scale (10%) uncertainties, where \unclustered energy" refers to energy from a reconstructed object that is not assigned to a jet with pT > 10 GeV or to a lepton with pT > 10 GeV. Since the estimate of the background is partly based on simulation, the signal and T background rates are a ected by similar sources of systematic uncertainty, such as the luminosity uncertainty of 2.6% [48]. The uncertainties in the lepton identi cation e ciency, lepton energy and momentum scale, pmiss scale, and trigger e ciency also contribute to the systematic uncertainty in the signal. The signal event acceptance for the VBF selection depends on the reconstruction and identi cation e ciency and jet energy scale of forward jets. The jet reconstruction-plusidenti cation e ciency is >98% for the entire and pT range, as is validated through the agreement observed between data and simulation in the distribution of jets, in particular at high , in control samples enriched with tt background events. The dominant uncertainty in the signal acceptance is due to the modelling of the kinematic properties of jets, and thus the VBF e ciency, for forward jets in the MadGraph simulation. This is investigated by comparing the predicted and measured mjj spectra in the Z+jets CRs. The level of agreement between the predicted and observed mjj spectra is better than 23%, which is assigned as a systematic uncertainty in the VBF e ciency for signal samples. The uncertainty in the signal acceptance due to the PDF set included in the simulated samples is evaluated in accordance with the PDF4LHC recommendations [49, 50] by comparing the results obtained using the CTEQ6.6L, MSTW08, and NNPDF10 PDF sets [ 42, 51, 52 ] with those from the default PDF set (CTEQ6L1). The dominant uncertainties that contribute to the mjj shape variations include the pTmissand jet energy scale uncertainties. Correlations of the uncertainty sources are discussed in section 8. 8 Results and interpretation combined results from all channels are shown in gure 5. Numerical results are given in tables 2 and 3. The observed numbers of events are seen to be consistent with the expected , (upper right) SS , (lower left) OS e , and (lower right) SS e signal regions. The signal scenario with me02 = m m~ = 195 GeV, and me01 = 0 GeV, as described in section 4, is shown. The signal eveen1ts are scaled = 200 GeV, up by a factor of 5 for purposes of visibility. The shaded band in the ratio plot includes the systematic and statistical uncertainties in the background prediction. SM background in all search regions. Therefore the search does not reveal any evidence for new physics. To quantify the sensitivity of this search, the results are interpreted in the context of the R-parity conserving minimal supersymmetric SM by considering production of charginos and neutralinos with two associated jets, as described in section 4. Models with a bino-like e01 and wino-like e02 and e1 are considered. Since the e02 and e1 belong to the same gauge h , (upper right) SS h (lower left) OS h h , and (lower right) SS h h signal regions. The signal scenario with me02 = m e1 events are scaled up by a factor of 5 for purposes of visibility. The shaded band in the ratio plot = 200 GeV, m~ = 195 GeV, and me01 = 0 GeV, as described in section 4, is shown. The signal includes the systematic and statistical uncertainties in the background prediction. e2 e1 group multiplet, we set m 0 = m and present results as a function of this common mass and the LSP mass m 0 . In the presence of a light slepton, `~ = ~e=~=~, it is likely e01 and the e20 to `+` e10 tchoantsidthereineg1`~ w=il~l adnedcaaysstuom`ing branching fractions B( e02 ! ~ ! other searches for the electroweak production of SUSY particles [17, 18], two scenarios are e01) = 1. To highlight how the VBF searches described in this paper complement . The results are interpreted by ~ ! e01) = 1 and B( e1 ! is shown. The signal eveen1ts are scaled up by a factor of 5 for purposes of visibility. The shaded band = 200 GeV, m~ = 195 GeV, and me01 = 0 GeV, as described in section 4, in the ratio plot includes the systematic and statistical uncertainties in the background prediction. Process Z+jets W+jets VV tt QCD VBF Z Total Observed Higgs boson 1:0 jj 1:7 0:5 1:7 0:1 4:3 2:8 24:0 3:7+21::19 4:2+32::35 3:1 0:7 19:0+22::34 1:1 0:5 | | 22 19:9 17:3 2:9 11:7 h jj 2:9 3:0 0:5 2:8 | | | 41 The uncertainties are statistical, including the statistical uncertainties from the control regions and simulated event samples. (compressed-mass spectrum). e1 considered: (i) m 0 = 0 GeV (uncompressed-mass spectrum) and (ii) m m 0 = 50 GeV e1 e1 The cumulative signal event acceptance is shown in table 4 at three stages of the analysis: accounting for the branching fractions for the SUSY event to yield the indicated two-lepton channel (BF), the acceptance following application of the central selection (Central), and the acceptance following the VBF selection (VBF). The average pT values of the Z+jets W+jets VV tt Single top QCD Higgs boson Total Observed h ( (e ( e h h ( h h h ) ) ) ) 2:1 3:1 0:3 0:1 | | | 4 jj e jj 0+10:7 0+30:0 1:9+00::42 3:5+00::79 | | | 5 0:5 9:3 1:1 6:7 0:2 2:3 0:2 2:8 | | | 14 0:1 0:1 0:5 0:1 6:5 1:2 7:6 8:4 0:9 0:9 9 5:4 0:3 The uncertainties are statistical, including the statistical uncertainties from the control regions and simulated event samples. Channel BF( 1`1 & 1`2) Central VBF quirements (see text). Note that the jet pT threshold for the jj and h hjj nal states is 30 GeV, while it is 50 GeV for the other nal states. e, , and h objects in signal events are relatively soft, because of the energy and momentum carried by the associated neutrinos in the decays. The OS and SS channels have similar signal acceptance because lepton pairs satisfying the event selection do not necessarily originate from the e20 or e1 e1 decays. The best signal sensitivity comes from the SS and e channels due to a better background suppression with respect to a given signal acceptance. The expected signal yields from simulation with me01 = 0 GeV and 50 GeV, are presented in table 5. The signal acceptance depends on the mass m~ of the m( e1 ; e01 ) = intermediate for m~: (i) a mass assumption m~ = 0:5m slepton. The results in table 5 are presented under two di erent assumptions xed-mass di erence assumption e1 + 0:5me01 . In the compressed-mass-spectrum scenario, m( e1 ; ~) = 5 GeV, and (ii) an averagefor which m average leptoen1 pT than the xed-mass assumption, and the acceptance is lower by a factor me01 = 50 GeV, the average-mass assumption yields signi cantly lower of 2{3. In the uncompressed-mass-spectrum scenario, with me01 =0 GeV, the average-mass assumption produces larger average lepton pT than the xed-mass assumption, yielding an event acceptance that is 1.3{1.8 times larger. f100, 95g (f100, 50g) hjj h hjj 16(29) 5:4(9:7) 2:3(4:1) 0:57(1:0) 1:4(0:5) 0:47(0:18) 0:12(0:05) m(e1 6:6(12) 1:8(3:1) 0:68(1:2) 0:17(0:30) correspond to the average-mass assumption m~ = 0:5me01 + 0:5m e1 . ; m~g correspond to the m(e1 ; ~) = 5 GeV, while the terms in parentheses (fme1 ; m~g) e1 The calculation of the exclusion limit is obtained by using the mjj distribution in each channel to construct a combined likelihood in bins of mjj and computing a 95% con dence level (CL) upper limit on the signal cross section using the asymptotic CLs criterion [53{ 55]. Systematic uncertainties are taken into account as nuisance parameters, which are removed by marginalization, assuming a gamma or log-normal prior for normalization parameters, and Gaussian priors for mass spectrum shape uncertainties. The combination of the eight search channels requires simultaneous analysis of the data from the individual channels, accounting for all statistical and systematic uncertainties and their correlations. Correlations among backgrounds, both within a channel and across channels, are taken into consideration in the limit calculation. For example, the uncertainties in physics object identi cation and reconstruction are treated as correlated for channels with a common particle in their nal states, while the uncertainty in the integrated luminosity is treated as correlated across channels. The uncertainties resulting from the number of simulated events, and from the event acceptance variation with di erent sets of PDFs in a given mjj bin, are treated as uncorrelated within a channel and correlated across channels. The uncertainties due to the closure tests are treated as uncorrelated within and across the di erent nal states. Figures 6 (left) and 6 (right) show the expected and observed limits as well as the theoretical cross section as functions of m for, respectively, the xed- and average-mass m~ assumptions. For the xed-mass assumep1tion with a compressed-mass spectrum (m me01 = 50 GeV), e02 and e1 gauginos with masses below 170 GeV are excluded, where the previous ATLAS and CMS SUSY searches do not probe. For the average-mass assumption e1 with an uncompressed-mass spectrum (me01 = 0), the corresponding limit is 300 GeV. These mass limits are conservatively determined using the theoretical cross section minus its one standard deviation uncertainty. The m [see the yellow band in gure 6 (right)]. refs. [17, 18] can be compared to the corresponding result of 300 GeV in the present analysis e1 limits of 320 and 380 GeV for me01 = 0 GeV in HJEP1(205)89 signal cross section is calculated with the VBF jet selection: jet pT > 30 GeV, j 1 2 < 0. (Left) The results for the xed-mass di erence assumption, in which m spectrum). m(Re01igh=t)5T0hGeeVcor(rceosmpopnredsisnegd-rmesauslstsspfoercttrhuema)vearnadgem-mea01ss=as0sGumeVpt(iounne,c1oinmpwrheiscshedm-m~as=s for me1 m~ = 5 GeV, 0:5m e1 A search is presented for non-coloured supersymmetric particles in the vector-boson fusion (VBF) topology using data corresponding to an integrated luminosity of 19.7 fb 1 collected with the CMS detector in proton-proton collisions at p s = 8 TeV. This is the rst search for SUSY in the VBF topology. The search utilizes events in eight di erent nal states covering both same- and opposite-sign dilepton pairs. The leptons considered are electrons, muons, and hadronically decaying leptons. The VBF topology requires two well-separated jets that appear in opposite hemispheres, with large invariant mass mjj . The observed mjj distributions do not reveal any evidence for new physics. The results are used to exclude a range of e1 and e20 gaugino masses. For models in which the e10 lightest-supersymmetricparticle mass is zero, and in which the e1 and e02 branching fractions to e1 and e02 masses up to 300 GeV are excluded at 95% CL. For a compressed-mass-spectrum scenario, in which m previous studies at the1e LHC have focused on strongly coupled supersymmetric particles, me01 = 50 GeV, the corresponding limit is 170 GeV. While many leptons are large, including searches for charginos and neutralinos produced in gluino or squark decay chains, and a number of studies have presented limits on the Drell-Yan production of charginos and neutralinos, this analysis obtains the most stringent limits to date on the production of charginos and neutralinos decaying to leptons in compressed-mass-spectrum scenarios de ned by the mass separation m = m e1 me01 < 50 GeV. Acknowledgments Bundes-ministerium Forschungs-gemeinschaft Forschungs-zentren We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative sta s at CERN and at other CMS institutes for their contributions to the success of the CMS e ort. In addition, we gratefully acknowledge the computing centres and personnel of the Worldwide LHC Computing Grid for delivering so e ectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: the Austrian Federal Ministry of Science, Research and Economy and the Austrian Science Fund; the Belgian Fonds de la Recherche Scienti que, and Fonds voor Wetenschappelijk Onderzoek; the Brazilian Funding Agencies (CNPq, CAPES, FAPERJ, and FAPESP); the Bulgarian Ministry of Education and Science; CERN; the Chinese Academy of Sciences, Ministry of Science and Technology, and National Natural Science Foundation of China; the Colombian Funding Agency (COLCIENCIAS); the Croatian Ministry of Science, Education and Sport, and the Croatian Science Foundation; the Research Promotion Foundation, Cyprus; the Ministry of Education and Research, Estonian Research Council via IUT23-4 and IUT23-6 and European Regional Development Fund, Estonia; the Academy of Finland, Finnish Ministry of Education and Culture, and Helsinki Institute of Physics; the Institut National de Physique Nucleaire et de Physique des Particules/CNRS, and Commissariat a l'Energie Atomique et aux Energies Alternatives/CEA, France; the Bundesministerium fur Bildung und Forschung, Deutsche Forschungsgemeinschaft, and Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany; the General Secretariat for Research and Technology, Greece; the National Scienti c Research Foundation, and National Innovation O ce, Hungary; the Department of Atomic Energy and the Department of Science and Technology, India; the Institute for Studies in Theoretical Physics and Mathematics, Iran; the Science Foundation, Ireland; the Istituto Nazionale di Fisica Nucleare, Italy; the Ministry of Science, ICT and Future Planning, and National Research Foundation (NRF), Republic of Korea; the Lithuanian Academy of Sciences; the Ministry of Education, and University of Malaya (Malaysia); the Mexican Funding Agencies (CINVESTAV, CONACYT, SEP, and UASLP-FAI); the Ministry of Business, Innovation and Employment, New Zealand; the Pakistan Atomic Energy Commission; the Ministry of Science and Higher Education and the National Science Centre, Poland; the Fundac~ao para a Ci^encia e a Tecnologia, Portugal; JINR, Dubna; the Ministry of Education and Science of the Russian Federation, the Federal Agency of Atomic Energy of the Russian Federation, Russian Academy of Sciences, and the Russian Foundation for Basic Research; the Ministry of Education, Science and Technological Development of Serbia; the Secretar a de Estado de Investigacion, Desarrollo e Innovacion and Programa Consolider-Ingenio 2010, Spain; the Swiss Funding Agencies (ETH Board, ETH Zurich, PSI, SNF, UniZH, Canton Zurich, and SER); the Ministry of Science and Technology, Taipei; the Thailand Center of Excellence in Physics, the Institute for the Promotion of Teaching Science and Technology of Thailand, Special Task Force for Activating Research and the National Science and Technology Development Agency of Thailand; the Scienti c and Technical Research Council of Turkey, and Turkish Atomic Energy Authority; the National Academy of Sciences of Ukraine, and State Fund for Fundamental Researches, Ukraine; the Science and Technology Facilities Council, U.K.; the US Department of Energy, and the US National Science Foundation. Individuals have received support from the Marie-Curie programme and the European Research Council and EPLANET (European Union); the Leventis Foundation; the A.P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy O ce; the Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Science and Industrial Research, India; the HOMING PLUS programme of the Foundation for Polish Science, co nanced from European Union, Regional Development Fund; the OPUS programme of the National Science Center (Poland); the Compagnia di San Paolo (Torino); the Consorzio per la Fisica (Trieste); MIUR project 20108T4XTM (Italy); the Thalis and Aristeia programmes co nanced by EU-ESF and the Greek NSRF; the National Priorities Research Program by Qatar National Research Fund; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University (Thailand); and the Welch Foundation, contract C-1845. Open Access. 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Zenoni, F. Zhang3 Ghent University, Ghent, Belgium K. Beernaert, L. Benucci, A. Cimmino, S. Crucy, D. Dobur, A. Fagot, G. Garcia, M. Gul, J. Mccartin, A.A. Ocampo Rios, D. Poyraz, D. Ryckbosch, S. Salva, M. Sigamani, N. Strobbe, M. Tytgat, W. Van Driessche, E. Yazgan, N. Zaganidis Universite Catholique de Louvain, Louvain-la-Neuve, Belgium S. Basegmez, C. Belu 4 , O. Bondu, S. Brochet, G. Bruno, R. Castello, A. Caudron, L. Ceard, G.G. Da Silveira, C. Delaere, D. Favart, L. Forthomme, A. Giammanco5, J. Hollar, A. Jafari, P. Jez, M. Komm, V. Lemaitre, A. Mertens, C. Nuttens, L. Perrini, A. Pin, K. Piotrzkowski, A. Popov6, L. Quertenmont, M. Selvaggi, M. Vidal Marono Universite de Mons, Mons, Belgium N. Beliy, G.H. Hammad Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil W.L. Alda Junior, G.A. Alves, L. Brito, M. Correa Martins Junior, M. Hamer, 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. Chinellato7, A. Custodio, E.M. Da Costa, D. De Jesus Damiao, C. De Oliveira Martins, S. Fonseca De Souza, L.M. Huertas Guativa, H. Malbouisson, D. Matos Figueiredo, L. Mundim, H. Nogima, W.L. Prado Da Silva, A. Santoro, A. Sznajder, E.J. Tonelli Manganote7, A. Vilela Pereira Universidade Estadual Paulista a, Universidade Federal do ABC b, S~ao Paulo, Brazil S. Ahujaa, C.A. Bernardesb, A. De Souza Santosb, S. Dograa, T.R. Fernandez Perez Tomeia, E.M. Gregoresb, P.G. Mercadanteb, C.S. Moona;8, S.F. Novaesa, Sandra S. Padulaa, D. Romero Abad, J.C. Ruiz Vargas Institute for Nuclear Research and Nuclear Energy, So a, Bulgaria A. Aleksandrov, V. Genchevy, R. Hadjiiska, P. Iaydjiev, M. Rodozov, S. Stoykova, G. Sultanov, M. Vutova University of So a, So a, 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. Plestina9, F. Romeo, S.M. Shaheen, J. Tao, C. Wang, Z. Wang, H. Zhang State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China J.C. Sanabria C. Asawatangtrakuldee, Y. Ban, Q. Li, S. Liu, Y. Mao, S.J. Qian, D. Wang, Z. Xu, W. Zou Universidad de Los Andes, Bogota, Colombia C. Avila, A. Cabrera, L.F. Chaparro Sierra, C. Florez, J.P. Gomez, B. Gomez Moreno, University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, Split, Croatia N. Godinovic, D. Lelas, D. Polic, I. Puljak, P.M. Ribeiro Cipriano University of Split, Faculty of Science, Split, Croatia Z. Antunovic, M. Kovac Institute Rudjer Boskovic, Zagreb, Croatia V. Brigljevic, K. Kadija, J. Luetic, S. Micanovic, 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. Finger10, M. Finger Jr.10 Academy of Scienti c Research and Technology of the Arab Republic of Egypt, Egyptian Network of High Energy Physics, Cairo, Egypt A.A. Abdelalim11;12, A. Awad13;14, A. Mahrous12, A. Radi14;13 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, J. Pekkanen, M. Voutilainen Helsinki Institute of Physics, Helsinki, Finland J. Harkonen, V. Karimaki, R. Kinnunen, T. Lampen, K. Lassila-Perini, S. Lehti, T. Linden, P. Luukka, T. Maenpaa, T. Peltola, E. Tuominen, J. Tuominiemi, E. Tuovinen, L. Wendland J. Talvitie, T. Tuuva Lappeenranta University of Technology, Lappeenranta, Finland 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, M. Machet, J. Malcles, J. Rander, A. Rosowsky, M. Titov, A. Zghiche Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France I. Antropov, S. Ba oni, F. Beaudette, P. Busson, L. Cadamuro, E. Chapon, C. Charlot, T. Dahms, O. Davignon, N. Filipovic, A. Florent, R. Granier de Cassagnac, S. Lisniak, L. Mastrolorenzo, P. Mine, I.N. Naranjo, M. Nguyen, C. Ochando, G. Ortona, P. Paganini, S. Regnard, R. Salerno, J.B. Sauvan, Y. Sirois, T. Strebler, Y. Yilmaz, A. Zabi Institut Pluridisciplinaire Hubert Curien, Universite de Strasbourg, Universite de Haute Alsace Mulhouse, CNRS/IN2P3, Strasbourg, France J.-L. Agram15, J. Andrea, A. Aubin, D. Bloch, J.-M. Brom, M. Buttignol, E.C. Chabert, N. Chanon, C. Collard, E. Conte15, X. Coubez, J.-C. Fontaine15, D. Gele, U. Goerlach, C. Goetzmann, A.-C. Le Bihan, J.A. Merlin2, K. Skovpen, P. Van Hove Centre de Calcul de l'Institut National de Physique Nucleaire et de Physique des Particules, CNRS/IN2P3, Villeurbanne, France S. Gadrat Universite de Lyon, Universite Claude Bernard Lyon 1, CNRS-IN2P3, Institut de Physique Nucleaire de Lyon, Villeurbanne, France S. Beauceron, C. Bernet, G. Boudoul, E. Bouvier, C.A. Carrillo Montoya, J. Chasserat, R. Chierici, D. Contardo, B. Courbon, P. Depasse, H. El Mamouni, J. Fan, J. Fay, S. Gascon, M. Gouzevitch, B. Ille, F. Lagarde, I.B. Laktineh, M. Lethuillier, L. Mirabito, A.L. Pequegnot, S. Perries, J.D. Ruiz Alvarez, D. Sabes, L. Sgandurra, V. Sordini, M. Vander Donckt, P. Verdier, S. Viret, H. Xiao Georgian Technical University, Tbilisi, Georgia T. Toriashvili16 Z. Tsamalaidze10 Tbilisi State University, Tbilisi, Georgia RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany C. Autermann, S. Beranek, M. Edelho , L. Feld, A. Heister, M.K. Kiesel, K. Klein, M. Lipinski, A. Ostapchuk, M. Preuten, F. Raupach, S. Schael, J.F. Schulte, T. Verlage, H. Weber, B. Wittmer, V. Zhukov6 RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany M. Ata, M. Brodski, E. Dietz-Laursonn, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, A. Guth, T. Hebbeker, C. Heidemann, K. Hoepfner, D. Klingebiel, S. Knutzen, P. Kreuzer, M. Merschmeyer, A. Meyer, P. Millet, M. Olschewski, K. Padeken, P. Papacz, T. Pook, M. Radziej, H. Reithler, M. Rieger, F. Scheuch, L. Sonnenschein, D. Teyssier, S. Thuer RWTH Aachen University, III. Physikalisches Institut B, Aachen, Germany V. Cherepanov, Y. Erdogan, G. Flugge, H. Geenen, M. Geisler, F. Hoehle, B. Kargoll, T. Kress, Y. Kuessel, A. Kunsken, J. Lingemann2, A. Nehrkorn, A. Nowack, I.M. Nugent, C. Pistone, O. Pooth, A. Stahl Deutsches Elektronen-Synchrotron, Hamburg, 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, E. Gallo, J. Garay Garcia, A. Geiser, A. Gizhko, P. Gunnellini, J. Hauk, M. Hempel17, H. Jung, A. Kalogeropoulos, O. Karacheban17, M. Kasemann, P. Katsas, J. Kieseler, C. Kleinwort, I. Korol, W. Lange, J. Leonard, K. Lipka, A. Lobanov, W. Lohmann17, R. Mankel, I. Mar n17, I.-A. Melzer-Pellmann, A.B. Meyer, G. Mittag, J. Mnich, A. Mussgiller, S. Naumann-Emme, A. Nayak, E. Ntomari, H. Perrey, D. Pitzl, R. Placakyte, A. Raspereza, B. Roland, M.O . Sahin, P. Saxena, T. Schoerner-Sadenius, M. Schroder, C. Seitz, S. Spannagel, K.D. Trippkewitz, R. Walsh, C. Wissing University of Hamburg, Hamburg, Germany V. Blobel, M. Centis Vignali, A.R. Draeger, J. Er e, E. Garutti, K. Goebel, D. Gonzalez, M. Gorner, J. Haller, M. Ho mann, R.S. Hoing, A. Junkes, R. Klanner, R. Kogler, T. Lapsien, T. Lenz, I. Marchesini, D. Marconi, M. Meyer, D. Nowatschin, J. Ott, F. Pantaleo2, T. Pei er, A. Perieanu, N. Pietsch, J. Poehlsen, D. Rathjens, C. Sander, H. Schettler, P. Schleper, E. Schlieckau, A. Schmidt, J. Schwandt, M. Seidel, V. Sola, H. Stadie, G. Steinbruck, H. Tholen, D. Troendle, E. Usai, L. Vanelderen, A. Vanhoefer, B. Vormwald Institut fur Experimentelle Kernphysik, Karlsruhe, Germany M. Akbiyik, C. Barth, C. Baus, J. Berger, C. Boser, E. Butz, T. Chwalek, F. Colombo, W. De Boer, A. Descroix, A. Dierlamm, S. Fink, F. Frensch, M. Gi els, A. Gilbert, Pardo, B. Maier, H. Mildner, M.U. Mozer, T. Muller, Th. Muller, M. Plagge, G. Quast, K. Rabbertz, S. Rocker, F. Roscher, H.J. Simonis, F.M. Stober, R. Ulrich, J. Wagner-Kuhr, S. Wayand, M. Weber, T. Weiler, C. Wohrmann, R. Wolf Institute of Nuclear and Particle Physics (INPP), NCSR Demokritos, Aghia Paraskevi, Greece A. Psallidas, I. Topsis-Giotis University of Athens, Athens, Greece G. Anagnostou, G. Daskalakis, T. Geralis, V.A. Giakoumopoulou, A. Kyriakis, D. Loukas, A. Agapitos, S. Kesisoglou, A. Panagiotou, N. Saoulidou, E. Tziaferi University of Ioannina, Ioannina, 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. Horvath18, F. Sikler, V. Veszpremi, G. Vesztergombi19, A.J. Zsigmond Institute of Nuclear Research ATOMKI, Debrecen, Hungary N. Beni, S. Czellar, J. Karancsi20, J. Molnar, Z. Szillasi University of Debrecen, Debrecen, Hungary M. Bartok21, A. Makovec, P. Raics, Z.L. Trocsanyi, B. Ujvari 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, J.B. Singh, G. Walia University of Delhi, Delhi, India Ashok Kumar, Arun Kumar, A. Bhardwaj, B.C. Choudhary, R.B. Garg, A. Kumar, S. Malhotra, M. Naimuddin, N. Nishu, K. Ranjan, R. Sharma, V. Sharma Saha Institute of Nuclear Physics, Kolkata, India S. Banerjee, S. Bhattacharya, K. Chatterjee, S. Dey, S. Dutta, Sa. Jain, N. Majumdar, A. Modak, K. Mondal, S. Mukherjee, S. Mukhopadhyay, A. Roy, D. Roy, S. Roy Chowdhury, S. Sarkar, M. Sharan Bhabha Atomic Research Centre, Mumbai, India A. Abdulsalam, R. Chudasama, D. Dutta, V. Jha, V. Kumar, A.K. Mohanty2, L.M. Pant, P. Shukla, A. Topkar Tata Institute of Fundamental Research, Mumbai, India T. Aziz, S. Banerjee, S. Bhowmik22, R.M. Chatterjee, R.K. Dewanjee, S. Dugad, S. Ganguly, S. Ghosh, M. Guchait, A. Gurtu23, G. Kole, S. Kumar, B. Mahakud, M. Maity22, N. Sur, B. Sutar, N. Wickramage24 Indian Institute of Science Education and Research (IISER), Pune, India S. Chauhan, S. Dube, S. Sharma Institute for Research in Fundamental Sciences (IPM), Tehran, Iran H. Bakhshiansohi, H. Behnamian, S.M. Etesami25, A. Fahim26, R. Goldouzian, M. Khakzad, M. Mohammadi Najafabadi, M. Naseri, S. Paktinat Mehdiabadi, F. Rezaei Hosseinabadi, B. Safarzadeh27, M. Zeinali University College Dublin, Dublin, Ireland M. Felcini, M. Grunewald INFN Sezione di Bari a, Universita di Bari b, Politecnico di Bari c, Bari, Italy M. Abbresciaa;b, C. Calabriaa;b, C. Caputoa;b, S.S. Chhibraa;b, A. Colaleoa, D. Creanzaa;c, L. Cristellaa;b, N. De Filippisa;c, M. De Palmaa;b, L. Fiorea, G. Iasellia;c, G. Maggia;c, M. Maggia, G. Minielloa;b, S. Mya;c, S. Nuzzoa;b, A. Pompilia;b, G. Pugliesea;c, R. Radognaa;b, A. Ranieria, G. Selvaggia;b, L. Silvestrisa;2, R. Vendittia;b, P. Verwilligena INFN Sezione di Bologna a, Universita di Bologna b, Bologna, Italy G. Abbiendia, C. Battilana2, A.C. Benvenutia, D. Bonacorsia;b, S. Braibant-Giacomellia;b, L. Brigliadoria;b, R. Campaninia;b, P. Capiluppia;b, A. Castroa;b, F.R. Cavalloa, G. Codispotia;b, M. Cu ania;b, G.M. Dallavallea, F. Fabbria, A. Fanfania;b, D. Fasanellaa;b, P. Giacomellia, C. Grandia, L. Guiduccia;b, S. Marcellinia, G. Masettia, A. Montanaria, F.L. Navarriaa;b, A. Perrottaa, A.M. Rossia;b, T. Rovellia;b, G.P. Sirolia;b, N. Tosia;b, R. Travaglinia;b C. Tuvea;b L. Viliania;b INFN Sezione di Catania a, Universita di Catania b, CSFNSM c, Catania, Italy G. Cappelloa, M. Chiorbolia;b, S. Costaa;b, F. Giordanoa;c, R. Potenzaa;b, A. Tricomia;b, INFN Sezione di Firenze a, Universita di Firenze b, Firenze, Italy G. Barbaglia, V. Ciullia;b, C. Civininia, R. D'Alessandroa;b, E. Focardia;b, S. Gonzia;b, V. Goria;b, P. Lenzia;b, M. Meschinia, S. Paolettia, G. Sguazzonia, A. Tropianoa;b, INFN Laboratori Nazionali di Frascati, Frascati, Italy L. Benussi, S. Bianco, F. Fabbri, D. Piccolo INFN Sezione di Genova a, Universita di Genova b, Genova, Italy V. Calvellia;b, F. Ferroa, M. Lo Veterea;b, M.R. Mongea;b, E. Robuttia, S. Tosia;b INFN Sezione di Milano-Bicocca a, Universita di Milano-Bicocca b, Milano, Italy L. Brianza, M.E. Dinardoa;b, S. Fiorendia;b, S. Gennaia, R. Gerosaa;b, A. Ghezzia;b, P. Govonia;b, S. Malvezzia, R.A. Manzonia;b, B. Marzocchia;b;2, D. Menascea, L. Moronia, M. Paganonia;b, D. Pedrinia, S. Ragazzia;b, N. Redaellia, T. Tabarelli de Fatisa;b Universita della Basilicata c, Potenza, Italy, Universita G. Marconi d, Roma, S. Buontempoa, N. Cavalloa;c, S. Di Guidaa;d;2, M. Espositoa;b, F. Fabozzia;c, A.O.M. Iorioa;b, G. Lanzaa, L. Listaa, S. Meolaa;d;2, M. Merolaa, P. Paoluccia;2, C. Sciaccaa;b, F. Thyssen Trento c, Trento, Italy INFN Sezione di Padova a, Universita di Padova b, Padova, Italy, Universita di P. Azzia;2, N. Bacchettaa, L. Benatoa;b, D. Biselloa;b, A. Bolettia;b, R. Carlina;b, A. Carvalho Antunes De Oliveiraa;b, P. Checchiaa, M. Dall'Ossoa;b;2, T. Dorigoa, U. Dossellia, F. Gasparinia;b, U. Gasparinia;b, F. Gonellaa, A. Gozzelinoa, S. Lacapraraa, M. Margonia;b, A.T. Meneguzzoa;b, F. Montecassianoa, J. Pazzinia;b, N. Pozzobona;b, P. Ronchesea;b, F. Simonettoa;b, E. Torassaa, M. Tosia;b, M. Zanetti, P. Zottoa;b, A. Zucchettaa;b;2, G. Zumerlea;b INFN Sezione di Pavia a, Universita di Pavia b, Pavia, Italy A. Braghieria, A. Magnania, P. Montagnaa;b, S.P. Rattia;b, V. Rea, C. Riccardia;b, P. Salvinia, I. Vaia, P. Vituloa;b INFN Sezione di Perugia a, Universita di Perugia b, Perugia, Italy L. Alunni Solestizia;b, M. Biasinia;b, G.M. Bileia, D. Ciangottinia;b;2, L. Fanoa;b, P. Laricciaa;b, G. Mantovania;b, M. Menichellia, A. Sahaa, A. Santocchiaa;b, A. Spieziaa;b INFN Sezione di Pisa a, Universita di Pisa b, Scuola Normale Superiore di Pisa c, Pisa, Italy K. Androsova;28, P. Azzurria, G. Bagliesia, J. Bernardinia, T. Boccalia, G. Broccoloa;c, R. Castaldia, M.A. Cioccia;28, R. Dell'Orsoa, S. Donatoa;c;2, G. Fedi, L. Foaa;cy, A. Giassia, M.T. Grippoa;28, F. Ligabuea;c, T. Lomtadzea, L. Martinia;b, A. Messineoa;b, F. Pallaa, A. Rizzia;b, A. Savoy-Navarroa;29, A.T. Serbana, P. Spagnoloa, P. Squillaciotia;28, R. Tenchinia, G. Tonellia;b, A. Venturia, P.G. Verdinia INFN Sezione di Roma a, Universita di Roma b, Roma, Italy L. Baronea;b, F. Cavallaria, G. D'imperioa;b;2, D. Del Rea;b, M. Diemoza, S. Gellia;b, C. Jordaa, E. Longoa;b, F. Margarolia;b, P. Meridiania, F. Michelia;b, G. Organtinia;b, R. Paramattia, F. Preiatoa;b, S. Rahatloua;b, C. Rovellia, F. Santanastasioa;b, P. Traczyka;b;2 INFN Sezione di Torino a, Universita di Torino b, Torino, Italy, Universita del Piemonte Orientale c, Novara, Italy N. Amapanea;b, R. Arcidiaconoa;c;2, S. Argiroa;b, M. Arneodoa;c, R. Bellana;b, C. Biinoa, N. Cartigliaa, M. Costaa;b, R. Covarellia;b, A. Deganoa;b, G. Dellacasaa, N. Demariaa, L. Fincoa;b;2, B. Kiania;b, C. Mariottia, S. Masellia, E. Migliorea;b, V. Monacoa;b, E. Monteila;b, M. Musicha, M.M. Obertinoa;b, L. Pachera;b, N. Pastronea, M. Pelliccionia, G.L. Pinna Angionia;b, F. Raveraa;b, A. Romeroa;b, M. Ruspaa;c, R. Sacchia;b, A. Solanoa;b, A. Staianoa HJEP1(205)89 S. Belfortea, V. Candelisea;b;2, M. Casarsaa, F. Cossuttia, G. Della Riccaa;b, B. Gobboa, C. La Licataa;b, M. Maronea;b, A. Schizzia;b, T. Umera;b, A. Zanettia 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, A. Sakharov, D.C. Son Chonbuk National University, Jeonju, Korea J.A. Brochero Cifuentes, H. Kim, T.J. Kim, M.S. Ryu Chonnam National University, Institute for Universe and Elementary Particles, Korea University, Seoul, Korea S. Lee, S.K. Park, Y. Roh Seoul National University, Seoul, Korea H.D. Yoo University of Seoul, Seoul, Korea M. Choi, H. Kim, 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 S. Choi, Y. Go, D. Gyun, B. Hong, M. Jo, H. Kim, Y. Kim, B. Lee, K. Lee, K.S. Lee, National Centre for Particle Physics, Universiti Malaya, Kuala Lumpur, Malaysia I. Ahmed, Z.A. Ibrahim, J.R. Komaragiri, M.A.B. Md Ali30, F. Mohamad Idris31, W.A.T. Wan Abdullah, M.N. Yusli 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 Cruz32, A. Hernandez-Almada, R. Lopez-Fernandez, A. Sanchez-Hernandez Universidad Iberoamericana, Mexico City, Mexico S. Carrillo Moreno, F. Vazquez Valencia Benemerita Universidad Autonoma de Puebla, Puebla, Mexico I. Pedraza, H.A. Salazar Ibarguen Universidad Autonoma de San Luis Potos , San Luis Potos , 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. Gorski, M. Kazana, K. Nawrocki, K. Romanowska-Rybinska, M. Szleper, P. Zalewski Institute of Experimental Physics, Faculty of Physics, University of Warsaw, G. Brona, K. Bunkowski, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski, M. MisWarsaw, Poland iura, M. Olszewski, M. Walczak Portugal Laboratorio de Instrumentac~ao e F sica Experimental de Part culas, Lisboa, P. Bargassa, C. Beir~ao Da Cruz E Silva, A. Di Francesco, P. Faccioli, P.G. Ferreira Parracho, M. Gallinaro, N. Leonardo, L. Lloret Iglesias, F. Nguyen, J. Rodrigues Antunes, J. Seixas, O. Toldaiev, D. Vadruccio, J. Varela, P. Vischia Joint Institute for Nuclear Research, Dubna, Russia S. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, I. Gorbunov, A. Kamenev, V. Karjavin, V. Konoplyanikov, A. Lanev, A. Malakhov, V. Matveev33, P. Moisenz, V. Palichik, V. Perelygin, S. Shmatov, S. Shulha, N. Skatchkov, V. Smirnov, A. Zarubin Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), Russia V. Golovtsov, Y. Ivanov, V. Kim34, 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 National Research Nuclear University 'Moscow Engineering Physics InstiA. Bylinkin P.N. Lebedev Physical Institute, Moscow, Russia V. Andreev, M. Azarkin35, I. Dremin35, M. Kirakosyan, A. Leonidov35, G. Mesyats, S.V. Rusakov, A. Vinogradov Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia A. Snigirev A. Baskakov, A. Belyaev, E. Boos, M. Dubinin36, L. Dudko, A. Ershov, A. Gribushin, V. Klyukhin, O. Kodolova, I. Lokhtin, I. Myagkov, S. Obraztsov, S. Petrushanko, V. Savrin, 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, University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia P. Adzic37, M. Ekmedzic, J. Milosevic, V. Rekovic Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT), Madrid, Spain J. Alcaraz Maestre, E. Calvo, M. Cerrada, M. Chamizo Llatas, N. Colino, B. De La Cruz, A. Delgado Peris, D. Dom nguez Vazquez, A. Escalante Del Valle, C. Fernandez Bedoya, J.P. Fernandez Ramos, J. Flix, M.C. Fouz, P. Garcia-Abia, O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, E. Navarro De Martino, A. Perez-Calero Yzquierdo, J. Puerta Pelayo, A. Quintario Olmeda, I. Redondo, L. Romero, M.S. Soares Universidad Autonoma de Madrid, Madrid, Spain C. Albajar, J.F. de Troconiz, M. Missiroli, D. Moran Universidad de Oviedo, Oviedo, Spain H. Brun, J. Cuevas, J. Fernandez Menendez, S. Folgueras, I. Gonzalez Caballero, E. Palencia Cortezon, J.M. Vizan Garcia Instituto de F sica de Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, Spain I.J. Cabrillo, A. Calderon, J.R. Castin~eiras De Saa, P. De Castro Manzano, J. Duarte Campderros, M. Fernandez, J. Garcia-Ferrero, 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 guez-Marrero, A. Ruiz-Jimeno, L. Scodellaro, I. Vila, R. Vilar Cortabitarte CERN, European Organization for Nuclear Research, Geneva, Switzerland D. Abbaneo, E. Au ray, 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. Colafranceschi38, 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, B. Dorney, T. du Pree, N. Dupont, A. Elliott-Peisert, G. Franzoni, W. Funk, D. Gigi, K. Gill, D. Giordano, M. Girone, F. Glege, R. Guida, S. Gundacker, M. Gutho , J. Hammer, P. Harris, J. Hegeman, V. Innocente, P. Janot, H. Kirschenmann, M.J. Kortelainen, K. Kousouris, K. Krajczar, P. Lecoq, C. Lourenco, M.T. Lucchini, N. Magini, L. Malgeri, M. Mannelli, A. Martelli, L. Masetti, F. Meijers, S. Mersi, E. Meschi, F. Moortgat, S. Morovic, M. Mulders, M.V. Nemallapudi, H. Neugebauer, S. Orfanelli39, L. Orsini, L. Pape, E. Perez, A. Petrilli, G. Petrucciani, A. Pfei er, D. Piparo, A. Racz, G. Rolandi40, M. Rovere, M. Ruan, H. Sakulin, C. Schafer, C. Schwick, A. Sharma, P. Silva, M. Simon, P. Sphicas41, D. Spiga, J. Steggemann, B. Stieger, M. Stoye, Y. Takahashi, D. Treille, A. Triossi, A. Tsirou, G.I. Veres19, N. Wardle, H.K. Wohri, A. Zagozdzinska42, 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, D. Renker, T. Rohe Institute for Particle Physics, ETH Zurich, Zurich, Switzerland F. Bachmair, L. Bani, L. Bianchini, M.A. Buchmann, B. Casal, G. Dissertori, M. Dittmar, M. Donega, M. Dunser, P. Eller, C. Grab, C. Heidegger, D. Hits, J. Hoss, G. Kasieczka, W. Lustermann, B. Mangano, A.C. Marini, M. Marionneau, P. Martinez Ruiz del Arbol, M. Masciovecchio, D. Meister, P. Musella, F. Nessi-Tedaldi, F. Pandol , J. Pata, F. Pauss, L. Perrozzi, M. Peruzzi, M. Quittnat, M. Rossini, A. Starodumov43, M. Takahashi, V.R. Tavolaro, K. Theo latos, R. Wallny Universitat Zurich, Zurich, Switzerland T.K. Aarrestad, C. Amsler44, L. Caminada, M.F. Canelli, V. Chiochia, A. De Cosa, C. Galloni, A. Hinzmann, T. Hreus, B. Kilminster, C. Lange, J. Ngadiuba, D. Pinna, P. Robmann, F.J. Ronga, D. Salerno, Y. Yang National Central University, Chung-Li, Taiwan M. Cardaci, K.H. Chen, T.H. Doan, Sh. Jain, R. Khurana, M. Konyushikhin, C.M. Kuo, W. Lin, Y.J. Lu, R. Volpe, S.S. Yu National Taiwan University (NTU), Taipei, Taiwan R. Bartek, P. Chang, Y.H. Chang, Y.W. Chang, Y. Chao, K.F. Chen, P.H. Chen, C. Dietz, F. Fiori, U. Grundler, W.-S. Hou, Y. Hsiung, Y.F. Liu, R.-S. Lu, M. Min~ano Moya, E. Petrakou, J.F. Tsai, Y.M. Tzeng Chulalongkorn University, Faculty of Science, Department of Physics, Bangkok, Thailand B. Asavapibhop, K. Kovitanggoon, G. Singh, N. Srimanobhas, N. Suwonjandee Cukurova University, Adana, Turkey A. Adiguzel, M.N. Bakirci45, Z.S. Demiroglu, C. Dozen, I. Dumanoglu, E. Eskut, S. Girgis, G. Gokbulut, Y. Guler, E. Gurpinar, I. Hos, E.E. Kangal46, A. Kayis Topaksu, G. Onengut47, K. Ozdemir48, A. Polatoz, D. Sunar Cerci49, M. Vergili, C. Zorbilmez Middle East Technical University, Physics Department, Ankara, Turkey I.V. Akin, B. Bilin, S. Bilmis, B. Isildak50, G. Karapinar51, U.E. Surat, M. Yalvac, M. Zeyrek Bogazici University, Istanbul, Turkey E.A. Albayrak52, E. Gulmez, M. Kaya53, O. Kaya54, T. Yetkin55 Istanbul Technical University, Istanbul, Turkey K. Cankocak, S. Sen56, F.I. Vardarl Institute for Scintillation Materials of National Academy of Science of Ukraine, Kharkov, Ukraine B. Grynyov Kharkov, Ukraine L. Levchuk, P. Sorokin National Scienti c Center, Kharkov Institute of Physics and Technology, 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. Newbold57, 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. Belyaev58, C. Brew, R.M. Brown, D.J.A. Cockerill, J.A. Coughlan, K. Harder, S. Harper, E. Olaiya, D. Petyt, C.H. Shepherd-Themistocleous, A. Thea, L. Thomas, I.R. Tomalin, T. Williams, W.J. Womersley, S.D. Worm Imperial College, London, United Kingdom M. Baber, R. Bainbridge, O. Buchmuller, A. Bundock, D. Burton, S. Casasso, M. Citron, D. Colling, L. Corpe, N. Cripps, P. Dauncey, G. Davies, A. De Wit, M. Della Negra, P. Dunne, A. Elwood, W. Ferguson, J. Fulcher, D. Futyan, G. Hall, G. Iles, M. Kenzie, R. Lane, R. Lucas57, L. Lyons, A.-M. Magnan, S. Malik, J. Nash, A. Nikitenko43, J. Pela, M. Pesaresi, K. Petridis, D.M. Raymond, A. Richards, A. Rose, C. Seez, A. Tapper, K. Uchida, M. Vazquez Acosta59, 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, U.S.A. A. Borzou, K. Call, J. Dittmann, K. Hatakeyama, A. Kasmi, H. Liu, N. Pastika The University of Alabama, Tuscaloosa, U.S.A. O. Charaf, S.I. Cooper, C. Henderson, P. Rumerio Boston University, Boston, U.S.A. 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, U.S.A. J. Alimena, E. Berry, S. Bhattacharya, D. Cutts, N. Dhingra, A. Ferapontov, A. Garabedian, U. Heintz, E. Laird, G. Landsberg, Z. Mao, M. Narain, S. Piperov, S. Sagir, T. Sinthuprasith, R. Syarif University of California, Davis, Davis, U.S.A. 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, U.S.A. R. Cousins, P. Everaerts, C. Farrell, J. Hauser, M. Ignatenko, D. Saltzberg, E. Takasugi, V. Valuev, M. Weber University of California, Riverside, Riverside, U.S.A. K. Burt, R. Clare, J. Ellison, J.W. Gary, G. Hanson, J. Heilman, M. Ivova PANEVA, P. Jandir, E. Kennedy, F. Lacroix, O.R. Long, A. Luthra, M. Malberti, M. Olmedo Negrete, A. Shrinivas, H. Wei, S. Wimpenny University of California, San Diego, La Jolla, U.S.A. J.G. Branson, G.B. Cerati, S. Cittolin, R.T. D'Agnolo, A. Holzner, R. Kelley, D. Klein, J. Letts, I. Macneill, D. Olivito, S. Padhi, M. Pieri, M. Sani, V. Sharma, S. Simon, M. Tadel, A. Vartak, S. Wasserbaech60, C. Welke, F. Wurthwein, A. Yagil, G. Zevi Della Porta University of California, Santa Barbara, Santa Barbara, U.S.A. D. Barge, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, K. Flowers, M. Franco Sevilla, P. Ge ert, C. George, F. Golf, L. Gouskos, J. Gran, J. Incandela, C. Justus, N. Mccoll, S.D. Mullin, J. Richman, D. Stuart, I. Suarez, W. To, C. West, J. Yoo California Institute of Technology, Pasadena, U.S.A. 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, U.S.A. V. Azzolini, A. Calamba, B. Carlson, T. Ferguson, M. Paulini, J. Russ, M. Sun, H. Vogel, I. Vorobiev University of Colorado Boulder, Boulder, U.S.A. J.P. Cumalat, W.T. Ford, A. Gaz, F. Jensen, A. Johnson, M. Krohn, T. Mulholland, U. Nauenberg, K. Stenson, S.R. Wagner Cornell University, Ithaca, U.S.A. J. Alexander, A. Chatterjee, J. Chaves, J. Chu, S. Dittmer, N. Eggert, N. Mirman, G. Nicolas Kaufman, J.R. Patterson, A. Rinkevicius, A. Ryd, L. Skinnari, L. So , W. Sun, S.M. Tan, W.D. Teo, J. Thom, J. Thompson, J. Tucker, Y. Weng, P. Wittich Fermi National Accelerator Laboratory, Batavia, U.S.A. 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. Grunendahl, O. Gutsche, J. Hanlon, D. Hare, R.M. Harris, J. Hirschauer, B. Hooberman, Z. Hu, S. Jindariani, M. Johnson, U. Joshi, A.W. Jung, B. Klima, B. Kreis, S. Kwany, S. Lammel, J. Linacre, D. Lincoln, R. Lipton, T. Liu, R. Lopes De Sa, J. Lykken, K. Maeshima, J.M. Marra no, V.I. Martinez Outschoorn, S. Maruyama, D. Mason, P. McBride, P. Merkel, K. Mishra, S. Mrenna, S. Nahn, C. Newman-Holmes, V. O'Dell, K. Pedro, O. Prokofyev, G. Rakness, E. Sexton-Kennedy, A. Soha, W.J. Spalding, L. Spiegel, L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger, E.W. Vaandering, C. Vernieri, M. Verzocchi, R. Vidal, H.A. Weber, A. Whitbeck, F. Yang, H. Yin University of Florida, Gainesville, U.S.A. D. Acosta, P. Avery, P. Bortignon, D. Bourilkov, A. Carnes, M. Carver, D. Curry, S. Das, G.P. Di Giovanni, R.D. Field, M. Fisher, I.K. Furic, J. Hugon, J. Konigsberg, A. Korytov, J.F. Low, P. Ma, K. Matchev, H. Mei, P. Milenovic61, G. Mitselmakher, L. Muniz, D. Rank, R. Rossin, L. Shchutska, M. Snowball, D. Sperka, J. Wang, S. Wang, J. Yelton Florida International University, Miami, U.S.A. S. Hewamanage, S. Linn, P. Markowitz, G. Martinez, J.L. Rodriguez Florida State University, Tallahassee, U.S.A. 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, U.S.A. V. Bhopatkar, M. Hohlmann, H. Kalakhety, D. Mareskas-palcek, T. Roy, F. Yumiceva University of Illinois at Chicago (UIC), Chicago, U.S.A. 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, U.S.A. B. Bilki62, W. Clarida, K. Dilsiz, S. Durgut, R.P. Gandrajula, M. Haytmyradov, V. Khristenko, J.-P. Merlo, H. Mermerkaya63, A. Mestvirishvili, A. Moeller, J. Nachtman, H. Ogul, Y. Onel, F. Ozok52, A. Penzo, C. Snyder, P. Tan, E. Tiras, J. Wetzel, K. Yi Johns Hopkins University, Baltimore, U.S.A. I. Anderson, B.A. Barnett, B. Blumenfeld, D. Fehling, L. Feng, A.V. Gritsan, P. Maksimovic, C. Martin, M. Osherson, M. Swartz, M. Xiao, Y. Xin, C. You The University of Kansas, Lawrence, U.S.A. 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, U.S.A. I. Chakaberia, A. Ivanov, K. Kaadze, S. Khalil, M. Makouski, Y. Maravin, A. Mohammadi, L.K. Saini, N. Skhirtladze, I. Svintradze, S. Toda Lawrence Livermore National Laboratory, Livermore, U.S.A. D. Lange, F. Rebassoo, D. Wright University of Maryland, College Park, U.S.A. C. Anelli, A. Baden, O. Baron, A. Belloni, B. Calvert, S.C. Eno, C. Ferraioli, J.A. Gomez, N.J. Hadley, S. Jabeen, R.G. Kellogg, T. Kolberg, J. Kunkle, Y. Lu, A.C. Mignerey, Y.H. Shin, A. Skuja, M.B. Tonjes, S.C. Tonwar Massachusetts Institute of Technology, Cambridge, U.S.A. A. Apyan, R. Barbieri, A. Baty, K. Bierwagen, S. Brandt, W. Busza, I.A. Cali, Z. Demiragli, L. Di Matteo, G. Gomez Ceballos, M. Goncharov, D. Gulhan, Y. Iiyama, G.M. Innocenti, M. Klute, D. Kovalskyi, Y.S. Lai, Y.-J. Lee, A. Levin, P.D. Luckey, C. Mcginn, C. Mironov, X. Niu, C. Paus, D. Ralph, C. Roland, G. Roland, J. Salfeld-Nebgen, G.S.F. Stephans, K. Sumorok, M. Varma, D. Velicanu, J. Veverka, J. Wang, T.W. Wang, B. Wyslouch, M. Yang, V. Zhukova University of Minnesota, Minneapolis, U.S.A. B. Dahmes, A. Finkel, A. Gude, P. Hansen, S. Kalafut, S.C. Kao, K. Klapoetke, Y. Kubota, Z. Lesko, J. Mans, S. Nourbakhsh, N. Ruckstuhl, R. Rusack, N. Tambe, J. Turkewitz University of Mississippi, Oxford, U.S.A. J.G. Acosta, S. Oliveros University of Nebraska-Lincoln, Lincoln, U.S.A. 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 Bu alo, Bu alo, U.S.A. M. Alyari, J. Dolen, J. George, A. Godshalk, I. Iashvili, J. Kaisen, A. Kharchilava, A. Kumar, S. Rappoccio Northeastern University, Boston, U.S.A. G. Alverson, E. Barberis, D. Baumgartel, M. Chasco, A. Hortiangtham, B. Knapp, 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, U.S.A. S. Stoynev, K. Sung, M. Trovato, M. Velasco University of Notre Dame, Notre Dame, U.S.A. K.A. Hahn, A. Kubik, N. Mucia, N. Odell, B. Pollack, A. Pozdnyakov, M. Schmitt, A. Brinkerho , N. Dev, M. Hildreth, C. Jessop, D.J. Karmgard, N. Kellams, K. Lannon, S. Lynch, N. Marinelli, F. Meng, C. Mueller, Y. Musienko33, T. Pearson, M. Planer, A. Reinsvold, R. Ruchti, G. Smith, S. Taroni, N. Valls, M. Wayne, M. Wolf, A. Woodard The Ohio State University, Columbus, U.S.A. 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, U.S.A. O. Driga, P. Elmer, J. Hardenbrook, P. Hebda, S.A. Koay, P. Lujan, D. Marlow, T. Medvedeva, M. Mooney, J. Olsen, C. Palmer, P. Piroue, X. Quan, H. Saka, D. Stickland, C. Tully, J.S. Werner, A. Zuranski University of Puerto Rico, Mayaguez, U.S.A. S. Malik Purdue University, West Lafayette, U.S.A. V.E. Barnes, D. Benedetti, D. Bortoletto, L. Gutay, M.K. Jha, M. Jones, K. Jung, M. Kress, D.H. Miller, N. Neumeister, F. Primavera, B.C. Radburn-Smith, X. Shi, I. Shipsey, D. Silvers, J. Sun, A. Svyatkovskiy, F. Wang, W. Xie, L. Xu, J. Zablocki Purdue University Calumet, Hammond, U.S.A. N. Parashar, J. Stupak Rice University, Houston, U.S.A. A. Adair, B. Akgun, Z. Chen, K.M. Ecklund, F.J.M. Geurts, M. Guilbaud, W. Li, B. Michlin, M. Northup, B.P. Padley, R. Redjimi, J. Roberts, J. Rorie, Z. Tu, J. Zabel University of Rochester, Rochester, U.S.A. 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 The Rockefeller University, New York, U.S.A. L. Demortier Rutgers, The State University of New Jersey, Piscataway, U.S.A. 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, K. Nash, S. Panwalkar, M. Park, S. Salur, S. Schnetzer, D. She eld, S. Somalwar, R. Stone, S. Thomas, P. Thomassen, M. Walker University of Tennessee, Knoxville, U.S.A. M. Foerster, G. Riley, K. Rose, S. Spanier, A. York Texas A&M University, College Station, U.S.A. O. Bouhali64, A. Castaneda Hernandez, A. Celik, M. Dalchenko, M. De Mattia, A. Delgado, S. Dildick, R. Eusebi, W. Flanagan, J. Gilmore, T. Kamon65, V. Krutelyov, R. Montalvo, R. Mueller, I. Osipenkov, Y. Pakhotin, R. Patel, A. Perlo , J. Roe, A. Rose, A. Safonov, A. Tatarinov, K.A. Ulmer2 Texas Tech University, Lubbock, U.S.A. N. Akchurin, C. Cowden, J. Damgov, C. Dragoiu, P.R. Dudero, J. Faulkner, S. Kunori, K. Lamichhane, S.W. Lee, T. Libeiro, S. Undleeb, I. Volobouev Vanderbilt University, Nashville, U.S.A. E. Appelt, A.G. Delannoy, S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, Y. Mao, A. Melo, H. Ni, P. Sheldon, B. Snook, S. Tuo, J. Velkovska, Q. Xu University of Virginia, Charlottesville, U.S.A. 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, U.S.A. J. Sturdy University of Wisconsin, Madison, U.S.A. C. Clarke, R. Harr, P.E. Karchin, C. Kottachchi Kankanamge Don, P. Lamichhane, D.A. Belknap, D. Carlsmith, M. Cepeda, A. Christian, S. Dasu, L. Dodd, S. Duric, E. Friis, B. Gomber, R. Hall-Wilton, M. Herndon, A. Herve, P. Klabbers, A. Lanaro, A. Levine, K. Long, R. Loveless, A. Mohapatra, I. Ojalvo, T. Perry, G.A. Pierro, G. Polese, I. Ross, T. Ruggles, T. Sarangi, A. Savin, A. Sharma, N. Smith, W.H. Smith, D. Taylor, N. Woods y: Deceased China 1: Also at Vienna University of Technology, Vienna, Austria 2: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland 3: Also at State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, 4: Also at Institut Pluridisciplinaire Hubert Curien, Universite de Strasbourg, Universite de Haute Alsace Mulhouse, CNRS/IN2P3, Strasbourg, France 5: Also at National Institute of Chemical Physics and Biophysics, Tallinn, Estonia 6: Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia 7: Also at Universidade Estadual de Campinas, Campinas, Brazil 8: Also at Centre National de la Recherche Scienti que (CNRS) - IN2P3, Paris, France 9: Also at Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France 10: Also at Joint Institute for Nuclear Research, Dubna, Russia 11: Also at Zewail City of Science and Technology, Zewail, Egypt 12: Now at Helwan University, Cairo, Egypt 13: Also at Ain Shams University, Cairo, Egypt 14: Now at British University in Egypt, Cairo, Egypt 15: Also at Universite de Haute Alsace, Mulhouse, France 16: Also at Tbilisi State University, Tbilisi, Georgia 17: Also at Brandenburg University of Technology, Cottbus, Germany 18: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary 19: Also at Eotvos Lorand University, Budapest, Hungary 20: Also at University of Debrecen, Debrecen, Hungary 21: Also at Wigner Research Centre for Physics, Budapest, Hungary 23: Now at King Abdulaziz University, Jeddah, Saudi Arabia 24: Also at University of Ruhuna, Matara, Sri Lanka 25: Also at Isfahan University of Technology, Isfahan, Iran 26: Also at University of Tehran, Department of Engineering Science, Tehran, Iran 27: Also at Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran 28: Also at Universita degli Studi di Siena, Siena, Italy 29: Also at Purdue University, West Lafayette, U.S.A. 30: Also at International Islamic University of Malaysia, Kuala Lumpur, Malaysia 31: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia 32: Also at Consejo Nacional de Ciencia y Tecnolog a, Mexico city, Mexico 33: Also at Institute for Nuclear Research, Moscow, Russia 34: Also at St. Petersburg State Polytechnical University, St. Petersburg, Russia 35: Also at National Research Nuclear University 'Moscow 36: Also at California Institute of Technology, Pasadena, U.S.A. 37: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia 38: Also at Facolta Ingegneria, Universita di Roma, Roma, Italy 39: Also at National Technical University of Athens, Athens, Greece 40: Also at Scuola Normale e Sezione dell'INFN, Pisa, Italy 41: Also at University of Athens, Athens, Greece 42: Also at Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland 43: Also at Institute for Theoretical and Experimental Physics, Moscow, Russia 44: Also at Albert Einstein Center for Fundamental Physics, Bern, Switzerland 45: Also at Gaziosmanpasa University, Tokat, Turkey 46: Also at Mersin University, Mersin, Turkey 47: Also at Cag University, Mersin, Turkey 48: Also at Piri Reis University, Istanbul, Turkey 49: Also at Adiyaman University, Adiyaman, Turkey 50: Also at Ozyegin University, Istanbul, Turkey 51: Also at Izmir Institute of Technology, Izmir, Turkey 52: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey 53: Also at Marmara University, Istanbul, Turkey 54: Also at Kafkas University, Kars, Turkey 55: Also at Yildiz Technical University, Istanbul, Turkey 56: Also at Hacettepe University, Ankara, Turkey Kingdom [1] P. 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The CMS collaboration, V. Khachatryan, A. M. Sirunyan, A. Tumasyan, W. Adam, E. Asilar, T. Bergauer, J. Brandstetter, E. Brondolin, M. Dragicevic, J. Erö, M. Flechl, M. Friedl, R. Frühwirth, V. M. Ghete, C. Hartl, N. Hörmann, J. Hrubec, M. Jeitler, V. Knünz, A. König, M. Krammer, I. Krätschmer, D. Liko, T. Matsushita, I. Mikulec, D. Rabady, B. Rahbaran, H. Rohringer, J. Schieck, R. Schöfbeck, J. Strauss, W. Treberer-Treberspurg, W. Waltenberger, C.-E. Wulz, V. Mossolov, N. Shumeiko, J. Suarez Gonzalez, 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. Van Remortel, A. Van Spilbeeck, 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. Van Doninck, P. Van Mulders, G. P. Van Onsem, I. Van Parijs, P. Barria, C. Caillol, B. Clerbaux, G. 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Feld, A. Heister, M. K. Kiesel. Search for supersymmetry in the vector-boson fusion topology in proton-proton collisions at \( \sqrt{s}=8 \) TeV, Journal of High Energy Physics, 2015, 189, DOI: 10.1007/JHEP11(2015)189