Measurements of differential jet cross sections in proton-proton collisions
at
p
ffiffiffi
s
¼ 7 TeV with the CMS detector
S. Chatrchyan et al.* (CMS Collaboration)
(Received 29 December 2012; published 3 June 2013; publisher error corrected 12 June 2013) Measurements of inclusive jet and dijet production cross sections are presented. Data from LHC proton-proton collisions atpffiffiffis¼ 7 TeV, corresponding to 5:0 fb1of integrated luminosity, have been collected with the CMS detector. Jets are reconstructed up to rapidity 2.5, transverse momentum 2 TeV, and dijet
invariant mass 5 TeV, using the anti-kT clustering algorithm with distance parameter R ¼ 0:7. The
measured cross sections are corrected for detector effects and compared to perturbative QCD predictions at next-to-leading order, using five sets of parton distribution functions.
DOI:10.1103/PhysRevD.87.112002 PACS numbers: 13.87.Ce, 12.38.Qk
I. INTRODUCTION
Events with high transverse momentum jets in proton-proton collisions are described by quantum chromodynam-ics (QCD) in terms of parton-parton scattering, where the outgoing scattered partons manifest themselves as had-ronic jets. Measurements of the inclusive jet and dijet cross sections can be used to test the predictions of perturbative QCD, constrain parton distribution functions (PDFs) of the proton, differentiate among PDF sets, and look for possible deviations from the standard model.
In this paper, measurements of the double-differential inclusive jet (p þ p ! jet þ X) and dijet (p þ p ! jet þ jetþ X) production cross sections are reported as functions of jet rapidity y and either jet transverse momentum pTor dijet invariant mass Mjj, at pffiffiffis¼ 7 TeV. The data were collected with the Compact Muon Solenoid (CMS) detec-tor at the CERN Large Hadron Collider (LHC) during the 2011 run and correspond to an integrated luminosity of 5:0 fb1, 2 orders of magnitude larger than the published LHC results from the 2010 run [1–3]. Jets are reconstructed up to rapidity 2.5, transverse momentum 2 TeV, and dijet invariant mass 5 TeV. The measured cross sections are corrected for detector effects and compared to the next-to-leading-order QCD predictions.
II. APPARATUS
The CMS coordinate system has its origin at the center of the detector, with the z axis pointing along the direction of the counterclockwise beam. The azimuthal angle is denoted as , the polar angle as , and the pseudorapidity is defined as ¼ ln ½tan ð=2Þ. The central feature of the CMS detector is a superconducting solenoid, of 6 m
internal diameter, that produces an axial magnetic field of 3.8 T. Within the field volume are a silicon pixel and strip tracker, a lead tungstate crystal electromagnetic calorime-ter (ECAL), and a brass/plastic scintillator hadronic calo-rimeter. Outside the field volume and in the forward region (3 < jj < 5) is an iron/quartz-fiber hadronic calorimeter. Muons are measured in gas ionization detectors embedded in the steel return yoke outside the solenoid, in the pseu-dorapidity range jj < 2:4. A detailed description of the CMS apparatus can be found in Ref. [4].
III. JET RECONSTRUCTION
The rapidity y and the transverse momentum pTof a jet with energy E and momentum ~p ¼ ðpx; py; pzÞ are defined as y ¼ ð1=2Þ ln ½ðE þ pzÞ=ðE pzÞ and pT¼ ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffip2
xþ p2y
q
. The inputs to the jet clustering algorithm are the four-momentum vectors of the reconstructed particle candi-dates. Each such candidate is constructed using the particle-flow technique [5], which combines the informa-tion from several subdetectors and is calibrated to account for the nonlinear and nonuniform response of the CMS calorimetric system to hadrons. Jets are reconstructed using the anti-kT clustering algorithm [6] with distance parameter R ¼ 0:7. The clustering is performed using four-momentum summation with the FASTJET package [7], where the chosen distance parameter allows for the capture of most of the parton shower and improves the dijet mass resolution with respect to smaller sizes. The total transverse energy ETand missing transverse energy ~EmissT are used in the event selection and are derived from the reconstructed particle-flow objects. They are defined as ET¼PiETi, with ETi¼ Eisin i, and E~missT ¼ PiðEisin icos ix þ E^ isin isin iyÞ, where the sum^ refers to all particle candidates and ^x, ^y are the unit vectors in the direction of the x and y axes.
The reconstructed jets require a small additional energy correction, mostly due to thresholds on reconstructed tracks and clusters in the particle-flow algorithm, and *Full author list given at the end of the article.
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various reconstruction inefficiencies. These jet energy cor-rections are derived using simulated events, generated by
PYTHIA6 (version 6.4.22) [8] and processed through the CMS detector simulation based on GEANT4 [9], and in
situ measurements with dijet, photonþ jet, and Z þ jet events [10]. These jet energy corrections correct recon-structed jets to the hadron level, as opposed to the parton level. An offset correction is also applied to account for the extra energy from additional proton-proton interactions within the same or neighboring bunch crossings (in-time and out-of-time pileup) [10]. The pileup effects are impor-tant for the lowest-pTjets (10% jet energy scale correction and 1% systematic uncertainty [11] for jets with pT 100 GeV) and progressively decrease with jet pT. For jets with pT> 200 GeV the pileup effects are negligible. The jet energy correction depends on and pTof the jet, and is applied as a multiplicative factor to the jet four-momentum vector. The factor is typically between 1.0 and 1.2 and is approximately uniform in . For a jet pT¼ 100 GeV the factor is 1.1, decreasing towards 1.0 with increasing pT. The typical jet pTresolution is 10% at pT¼ 100 GeV. The dijet mass Mjjis calculated from the corrected four-momentum vectors of the two jets with the highest pT(leading jets). The relative dijet mass resolution, estimated from the simulation, ranges from 7% at Mjj ¼ 0:2 TeV to 3% at Mjj ¼ 3 TeV.
IV. DATA SAMPLES AND EVENT SELECTION The data samples used for this measurement were col-lected with single-jet high-level triggers (HLT) [12] that require at least one jet in the event to have pT> 60, 110, 190, 240, or 370 GeV, respectively, in corrected jet trans-verse momentum. The online jet reconstruction uses only calorimetric information and the resulting HLT jets typi-cally have worse energy resolution than the offline particle-flow jets. The lower-pT triggers were prescaled and the corresponding integrated luminosity of each trigger sam-ple,Leff, is listed in TableI. In the offline analysis, events are required to have at least one well-reconstructed proton-proton interaction vertex [13]. In order to suppress nonphysical jets, i.e., jets resulting from noise in the elec-tromagnetic and/or hadronic calorimeters, the jets are re-quired to satisfy the following identification criteria. Each jet should contain at least two particles, one of which is a charged hadron, and the jet energy fraction carried by neutral hadrons and photons should be less than 90%. These criteria have an efficiency of greater than 99% for
physical jets, while the probability for a nonphysical jet to pass the criteria is less than 106.
The inclusive single-jet cross section measurements are made in five rapidity regions of size jyj ¼ 0:5 over the range 0.0–2.5. Jets that do not satisfy the jet identification criteria are discarded and events are required to contain at least one jet that satisfies these criteria. In order to avoid any trigger bias, the jets are additionally required to have pT> 110, 200, 300, 360, and 510 Gev for the five single-jet HLT triggers used, respectively. Figure 1(top) shows the trigger efficiency as a function of the jet pT, for the central rapidity bin jyj < 0:5 and for the highest trigger threshold. The efficiency of each trigger path has been measured using events collected with a lower threshold single-jet trigger and confirmed with events collected with single-muon triggers.
Background events due to instrumental noise, beam halo effects, or proton-proton collisions with leptons in the final state that might survive the jet identification criteria are further suppressed by requiring Emiss
T =ET< 0:3. Hard QCD processes do not generate true Emiss
T and because of the good energy resolution the measured values of EmissT in such events are small compared to the total transverse energy. Hence, the distribution of the variable Emiss
T =ET
peaks close to zero for QCD events, while some back-ground events give larger values. Figure 2(top) shows a
TABLE I. The integrated luminosity for each of the data
samples.
Min. jet trigger pT(GeV) 60 110 190 240 370
Jet trigger name Jet60 Jet110 Jet190 Jet240 Jet370
Leff(pb1) 0.41 7.3 152 512 4980 (GeV) T Jet p 250 300 350 400 450 500 550 600 650 700 T rigger Ef ficiency 0 0.2 0.4 0.6 0.8 1 |y| < 0.5 Jet370 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) jj M 400 600 800 1000 1200 1400 T rigger Ef ficiency 0 0.2 0.4 0.6 0.8 1 < 0.5 max |y| Jet370 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k
FIG. 1. Trigger efficiency as a function of the jet pT(top) and dijet mass Mjj(bottom) for the 370 GeV single-jet trigger and for the central rapidity bins.
typical distribution of the variable Emiss
T =ET for events with at least one jet with pT> 510 GeV, collected with the 370 GeV single-jet trigger. The data points exceed the QCD predictions at large values of Emiss
T . This tail is dominated by processes such as Z þ jetðsÞ, where the Z boson decays to neutrinos, and W þ jetðsÞ, where the W boson decays to leptons. No events from instrumental and beam halo effects were found to survive the jet iden-tification criteria, and therefore the additional Emiss
T =ET
selection only removes events from processes that produce true Emiss
T .
For the dijet measurement, at least two jets with pT1> 60 GeV and pT2> 30 GeV and satisfying the tight identification criteria are required. If either of the two leading jets fails the identification criteria, the event is discarded. The dijet measurement is performed in five rapidity regions of size jymaxj ¼ 0:5, defined by the maximum absolute rapidity ymax ¼ signðj max ðy1; y2Þj j min ðy1; y2ÞjÞ max ðjy1j; jy2jÞ of the two leading jets in the event. The use of the variablejyjmax jymaxj divides
the phase space of the dijet system into exclusive rapidity bins, which correspond to different scattering angles in the center-of-mass frame.
Low values ofjyjmax probe s-channel scattering at large angles, while large values ofjyjmax probe t-channel scat-tering at small angles. For each rapidity bin the trigger efficiency is expressed as a function of Mjj, and the events are required to satisfy a minimum mass threshold, which increases withjyjmax. Figure1(bottom) shows the trigger efficiency for the central rapidity bin and for the highest trigger threshold. Because of the dijet topology, no further cut is needed on the Emiss
T =ETvariable, as can be seen in Fig.2(bottom).
V. MEASUREMENT OF THE DIFFERENTIAL JET AND DIJET CROSS SECTIONS
In this section the reconstruction of the jet transverse momentum and dijet mass spectra from the different samples is presented. Then the unfolding procedure, which translates the reconstructed spectra into true spectra, is described. Finally, the experimental uncertainties related to the measurements are described and discussed.
A. Determination of transverse momentum and dijet mass spectra
The jet pT(dijet invariant mass) spectrum is obtained by populating each bin with the number of jets (events) col-lected using the highest threshold trigger which gives more than 99% trigger efficiency. Then, the yields from each trigger path are scaled according to the corresponding prescale value for this path (effective luminosity), as shown in Table I. Figure 3 shows the reconstructed spectra for inclusive jets (top) and dijets (bottom), in the central rapidity bin, decomposed into the five contributing trigger paths.
The observed inclusive jet yields are transformed into double-differential cross sections as follows:
d2 dpTdy ¼ 1 Leff Njets pTð2 jyjÞ; (1) where Njets is the number of jets in the bin, Leff is the integrated luminosity of the data sample from which the events are taken, is the product of the trigger and event selection efficiencies, both of which are greater than 99%, and pT and jyj are the transverse momentum and rapidity bin widths, respectively. The width of the pT bins is proportional to the pT resolution and so increases with pT. The statistical uncertainty assigned to each pTbin takes into account the number of independent events that contribute at least one jet in the bin. The largest fraction (more than 90%) of the observed jets in each pT bin originates from different events; however, a small fraction of events contributes more than one jet. Such events are
T E Σ / miss T E 0 0.2 0.4 0.6 0.8 1 Events 1 10 2 10 3 10 4 10 5 10 6 10 > 510 GeV T Leading jet p ) -1 Data ( 5.0 fb QCD Simulation < 0.3 T E Σ / miss T E = 7 TeV s CMS T E Σ / miss T E 0 0.2 0.4 0.6 0.8 1 Events 1 10 2 10 3 10 4 10 > 910 GeV jj < 0.5, M max |y| ) -1 Data ( 5.0 fb QCD Simulation = 7 TeV s CMS
FIG. 2 (color online). Distribution of FTmiss=ET for data events (black points) and simulated QCD events (continuous line) with at least one jet with pT> 510 GeV (top) and for dijet events withjyjmax < 2:5 and Mjj> 910 GeV (bottom), collected with the 370 GeV single-jet trigger. The distribution from the inclusive jet selection is shown before the offline selection Emiss
T =ET< 0:3. The larger tail in the data is caused by other processes with true Emiss
T [such as Z þ jetðsÞ, where the Z boson decays to neutrinos, and W þ jetðsÞ, where the W boson decays to leptons].
typically back-to-back dijet events, so closely balanced in pTthat both jets end up in the samejyj and pTbin.
The statistical uncertainty in the number of jets in a bin is estat ¼pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffið4 3fÞ=ð2 fÞpffiffiffiffiffiffiffiffiffiNjets, where f ¼ N1=Nev is the fraction of events that contribute one jet in the given bin. The formula is valid under the assumption that the number of events that contribute more than two jets in each bin is negligible, which has been verified for the current measurement.
The observed dijet yields are transformed into double-differential cross sections as follows:
d2 dMjjdymax ¼ 1 Leff N Mjjð2 jyjmaxÞ; (2) where Mjj and jyjmax are the mass and rapidity bin widths, respectively. The size of the dijet mass bins is approximately equal to or larger than the mass resolution at the bin center, while the bins at the edge of the spectrum have been merged to assure a minimal number of events in each bin.
B. Unfolding
Because of the detector resolution and the steeply falling spectra, the measured differential cross sections are
smeared with respect to the particle-level cross sections. Each pTand mass bin contains events that have migrated in from neighboring bins and is missing events that have migrated out. For a steeply falling spectrum more events migrate into a bin than out. In order to allow for a direct comparison of experimental measurements with corre-sponding results from other experiments and with QCD predictions, the spectra are unfolded in order to correct for detector effects. The response matrix is obtained from the detector simulation and corrected for the measured differ-ences in the resolution between data and simulation [10]. Figure 4shows the response matrices for the jet pT (top) and the dijet mass (bottom) in the central rapidity bins. The unfolding is done with the RooUnfold package [14] using the D’Agostini method [15].
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 (GeV) T Measured Jet p 200 300 1000 2000 (GeV) T T rue Jet p 200 1000 2000 |y| < 0.5 = 7 TeV s R = 0.7 T anti-k CMS Simulation 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 (GeV) jj Measured M 200 300 1000 2000 (GeV)jj Tr u e M 200 1000 2000 3000 4000 < 0.5 max |y| = 7 TeV s R = 0.7 T anti-k CMS Simulation
FIG. 4 (color online). Response matrices for the inclusive jet pT spectrum (top) and the dijet mass spectrum (bottom) in the central rapidity bins.
(GeV) T Jet p 200 300 400 1000 2000 Prescale / GeV× Jets -3 10 -1 10 10 3 10 5 10 7 10 8 10 |y| < 0.5 Jet60 Jet110 Jet190 Jet240 Jet370 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) jj M 200 300 400 1000 2000 3000 Prescale / GeV× Events -3 10 -1 10 10 3 10 5 10 6 10 < 0.5 max |y| Jet60 Jet110 Jet190 Jet240 Jet370 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k
FIG. 3 (color online). Spectrum construction from individual trigger paths. Top: inclusive jet pT spectrum for jyj < 0:5. Bottom: dijet mass spectrum for jyjmax < 0:5. The different markers indicate different trigger paths.
(GeV)
jj
M
200 300 400 1000 2000 3000
Cross section uncertainty
-0.2 -0.1 0 0.1 0.2 0.3 < 0.5 max |y| Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) jj M 300 400 500 1000 2000 3000
Cross section uncertainty
-0.2 -0.1 0 0.1 0.2 0.3 < 1.0 max 0.5 < |y| Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) jj M 500 1000 2000 3000 4000
Cross section uncertainty
-0.2 -0.1 0 0.1 0.2 0.3 < 1.5 max 1.0 < |y| Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) jj M 600 1000 2000 3000 4000
Cross section uncertainty
-0.4 -0.2 0 0.2 0.4 0.6 < 2.0 max 1.5 < |y| Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) jj M 2000 3000 4000 5000
Cross section uncertainty
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 < 2.5 max 2.0 < |y| Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) T Jet p 200 300 400 1000 2000
Cross section uncertainty
|y| < 0.5 Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k -0.3 -0.2 -0.1 0 0.1 0.2 0.3 (GeV) T Jet p 200 300 400 1000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 < |y| < 1.0 Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) T Jet p 200 300 400 500 1000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 1.0 < |y| < 1.5 Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) T Jet p 200 300 400 500 1000
Cross section uncertainty
-0.4 -0.2 0 0.2 0.4 0.6 1.5 < |y| < 2.0 Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k (GeV) T Jet p 200 300 400 500 600
Cross section uncertainty
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 2.0 < |y| < 2.5 Total JES Unfolding Luminosity CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k
FIG. 5 (color online). Effect of the relative experimental uncertainties for the inclusive jet (left column) and dijet (right column) cross section measurements, and for all fivejyj and jyjmax bins, respectively. The upward and downward uncertainties are estimated separately.
(GeV)
T
Jet p
200 300 400 1000 2000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 |y| < 0.5 Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) jj M 200 300 400 1000 2000 3000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 < 0.5 max |y| Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) T Jet p 200 300 400 1000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.5 < |y| < 1.0 Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) jj M 300 400 500 1000 2000 3000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 < 1.0 max 0.5 < |y| Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) T Jet p 200 300 400 500 1000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 1.0 < |y| < 1.5 Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) jj M 500 1000 2000 3000 4000
Cross section uncertainty
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 < 1.5 max 1.0 < |y| Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) T Jet p 200 300 400 500 1000
Cross section uncertainty
-0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 1.5 < |y| < 2.0 Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) jj M 600 1000 2000 3000 4000
Cross section uncertainty
-0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 < 2.0 max 1.5 < |y| Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) T Jet p 200 300 400 500 600
Cross section uncertainty
-1 -0.5 0 0.5 1 2.0 < |y| < 2.5 Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k (GeV) jj M 2000 3000 4000 5000
Cross section uncertainty
-0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 < 2.5 max 2.0 < |y| Total PDF Nonpert. Scale NNPDF2.1 = 7 TeV s R = 0.7 T anti-k
FIG. 6 (color online). Effect of the relative theoretical uncertainties for the inclusive jet (left column) and dijet (right column) cross section measurements for all fivejyj and jyjmax bins, respectively. The upward and downward uncertainties are estimated separately.
C. Experimental uncertainties
The dominant experimental uncertainties are related to the jet energy scale (JES), the luminosity, and the jet pT resolution. Other sources of systematic uncertainty, such as the jet angular resolution, are negligible. The agreement of the results for positive and negative rapidities has also been confirmed. Figure5shows the effects of the experimental uncertainties in all rapidity bins for the cross section measurements. For rapidities up to jyj ¼ 1:5 the total uncertainty of both cross sections ranges from 5% at low pTor Mjjto 20% at high pTor Mjj, respectively. For higher rapidities the total uncertainty increases to 10%–30% in both cases, with the exception of the highest dijet mass bin in the outer rapidity region of 2:0 < jyjmax < 2:5, where the uncertainty is substantially larger. A discussion of the individual contributions to the uncertainty follows.
1. Jet energy scale uncertainty
The jet energy scale is the dominant source of systematic uncertainty. Because of the steep slope of the pTspectrum, a small uncertainty in the pT scale translates into a large uncertainty in the cross section for a given value of pT. The jet energy scale uncertainty is dependent on pTand and has been estimated to be 2.0%–2.5% [11]. The individual, uncorrelated contributions to the JES uncertainty have been estimated and are discussed below.
The JES uncertainty sources account for the pT and dependence of the JES within the total uncertainty. For the phase space of jets considered here, 16 mutually uncorre-lated sources contribute to the total uncertainty, where each such source represents a signed 1 variation from a given systematic effect for each point in ðpT; Þ. Summing up separately the positive or negative variations of the sources in quadrature will reproduce the total upward and down-ward JES uncertainties at each point. The uncertainties from all 16 independent sources are included in the Supplemental Material [16] and in the HEPDATA record for this paper; the cross section measurements and other details are also tabulated therein.
The uncertainty sources are divided into four broad categories: pileup effects, relative calibration of jet energy scale versus , absolute energy scale including pT depen-dence, and differences in quark- and gluon-initiated jets. The first category, containing pileup effects, has relatively little impact on the analyses presented in this paper.
The second category, containing -dependent effects, parametrizes the possible relative variations in JES, which for the dijet and inclusive jet analyses lead to correlations between rapidity bins. In principle these effects could also have a pTdependence, but systematic studies on data and Monte Carlo (MC) events indicate that the pT and dependence of the uncertainties factorize to a good approximation.
The third category deals with the uncertainty in the absolute energy scale and its pT dependence and is the
most relevant one for these analyses. The photonþ jet and Z þ jet events only constrain the JES directly in a limited jet pT range of about 30–600 GeV, and the response at higher (and lower) pTis estimated by MC simulation. The pT-dependent uncertainty arising from modeling of the underlying event and jet fragmentation is obtained by comparing predictions from PYTHIA6 and HERWIG++. Most studies show that both generators agree with the data with differences comparable to those seen between data and MC. The uncertainty arising from the calorimeter response to single hadrons is estimated by varying the response parametrization by 3% around the central value. The final uncertainty arises from differences in the JES for quark- and gluon-initiated jets and is determined from MC studies. (GeV) T Jet p 200 300 1000 2000 dy (pb/GeV) T /dp σ 2 d -5 10 -1 10 3 10 7 10 11 10 13 10 ) 4 10 × |y| < 0.5 ( ) 3 10 × 0.5 < |y| < 1.0 ( ) 2 10 × 1.0 < |y| < 1.5 ( ) 1 10 × 1.5 < |y| < 2.0 ( ) 0 10 × 2.0 < |y| < 2.5 ( CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k T = p F µ = R µ NP Corr. ⊗ NNPDF2.1 (GeV) jj M 200 1000 2000 (pb/GeV) max dyjj /dM σ 2 d -6 10 -3 10 1 3 10 6 10 9 10 10 10 0 ) 10 × < 0.5 ( max |y| ) 1 10 × < 1.0 ( max 0.5 < |y| ) 2 10 × < 1.5 ( max 1.0 < |y| ) 3 10 × < 2.0 ( max 1.5 < |y| ) 4 10 × < 2.5 ( max 2.0 < |y| CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k ave T = p F µ = R µ NP Corr. ⊗ NNPDF2.1
FIG. 7 (color online). Inclusive jet (top) and dijet (bottom) cross sections for the five different rapidity bins, for data (markers) and theory (thick lines) using the NNPDF2.1 PDF set.
2. Luminosity uncertainty
The luminosity uncertainty is estimated to be 2.2% [17], which can be directly translated into a 2.2% uncertainty on the cross section normalization. It is fully correlated across all pTand mass bins.
3. Unfolding uncertainty
The unfolding correction is closely related to the depen-dence on the pTand Mjjresolution and the spectrum slope. For the inclusive jet pTspectrum it varies between 5% and 10%, while for the dijet mass spectrum it ranges between 2% and 5%. The shape of the unfolding correction and
uncertainty as displayed in Fig.5is understood as follows: the resolution in the observable, pTor Mjj, improves when going from low to high values. As a consequence the effect of smearing is more pronounced in the lower pT or Mjj region. On the other hand the pTand Mjj spectra become steeper when approaching the kinematic limit at high pTor Mjj, leading again to a larger smearing effect than observed at medium values.
The uncertainty introduced by the unfolding is caused by the modeling of the jet pT(dijet mass) resolution and the jet pT (dijet mass) spectrum in the simulation. In order to estimate the sensitivity of the correction to these inputs, the
(GeV) T Jet p 200 300 400 Ratio to NNPDF2.1 0.6 1 1.2 1.4 1.6 |y| < 0.5Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty jj Ratio to NNPDF2.1 1.5 < 0.5 max |y| Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty (GeV) T Jet p Ratio to NNPDF2.1 1.4 1.6 0.5 < |y| < 1.0Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty jj 1.5 < 1.0 max 0.5 < |y| Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty 1.4 1.6 1.0 < |y| < 1.5Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty 1.5 < 1.5 max 1.0 < |y| Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty (GeV) M 200 300 400 1000 2000 3000 1000 2000 0.8 T Ratio to NNPDF2.1 (GeV) jj M Ratio to NNPDF2.1 Ratio to NNPDF2.1 500 1000 2000 3000 4000 0.5 1 1 1.2 (GeV) Jet p 200 300 400 500 1000 0.6 0.8 1 1.2 200 300 400 1000 0.6 0.8 0.5 1 (GeV) M 300 400 500 1000 2000 3000 0.5 1
FIG. 8 (color online). Ratio of inclusive jet (left) and dijet (right) cross sections to the theoretical prediction using the central value of the NNPDF2.1 PDF set for the first threejyj and jyjmax bins, respectively. The solid histograms show the ratio of the cross sections calculated with the other PDF sets to that calculated with NNPDF2.1. The experimental and theoretical systematic uncertainties are represented by the continuous and hatched bands, respectively.
jet pTresolution is varied by10% and the jet (dijet mass) spectrum slope by 5%. The former is motivated by the observed difference between data and simulation in the jet energy resolution [10], and the latter is a conservative esti-mate based on comparisons of the theoretical and measured spectrum shapes. An additional constant 2% uncertainty is assigned to the dependence on the unfolding method. Overall, the unfolding uncertainty is of the order of 3%–4%, and is fully correlated across the pTand mass bins.
4. Other uncertainty sources
The contributions from small trigger and jet identification inefficiencies, time dependence of the jet pTresolution, and uncertainty on the trigger prescale factor have been shown to be much smaller than 1%. To account for these residual effects a conservative uncertainty of 1% is assigned to each jet pTand dijet mass bin, uncorrelated across the bins.
VI. THEORETICAL PREDICTIONS
The theoretical predictions for the jet cross sections consist of a next-to-leading-order (NLO) QCD calculation and a nonperturbative correction to account for the multi-parton interactions (MPI) and hadronization effects.
A. NLO calculations
The NLO calculations are performed using the NLO-Jetþ þ program (v2.0.1) [18] within the framework of the fastNLO package (v1.4) [19]. The renormalization and factorization scales (Rand F) for the inclusive and dijet measurements are identified with the jet pT and the average transverse momentum pave
T of the two jets, respec-tively. The NLO calculation is performed using five differ-ent PDF sets: CT10 [20], MSTW2008NLO [21], NNPDF2.1 [22], HERAPDF1.5 [23], and ABKM09 [24] at the corresponding default values of the strong coupling constant sðMZÞ ¼ 0:1180, 0.120, 0.119, 0.1176, and 0.1179, respectively.
B. Systematic uncertainties
The PDF variation introduces uncertainties in the theo-retical prediction of up to 30%, while the variation of sðMZÞ by 0:001 introduces an additional 1%–2% uncer-tainty. The uncertainty due to the choice of factorization and renormalization scales is estimated as the maximum devia-tion at the six points (F=; R=Þ ¼ ð0:5; 0:5Þ, (2, 2), (1, 0.5), (1, 2), (0.5, 1), (2, 1), where ¼ pT(inclusive) or ¼ paveT (dijet). An additional uncertainty of at most 10% is caused by the nonperturbative correction. The scale
(GeV) T Jet p 2.5 3 1.5 < |y| < 2.0 Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty (GeV) jj M 1.5 < 2.0 max 1.5 < |y| Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty 1.5 2 2.5 3 2.0 < |y| < 2.5 Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty 2 3 2.0 < |y|max < 2.5 Data CT10 HERA1.5 MSTW2008 ABKM09 CMS = 7 TeV s -1 L = 5.0 fb R = 0.7 T anti-k Exp. Uncertainty Theo. Uncertainty Ratio to NNPDF2.1 Ratio to NNPDF2.1 (GeV) jj M 1000 2000 3000 4000 5000 Ratio to NNPDF2.1 (GeV) T Jet p 200 300 400 500 600 Ratio to NNPDF2.1 200 300 400 500 1000 1 600 1000 2000 3000 4000 0.5 0 1 0.5 1 2 1.5 1
FIG. 9 (color online). Ratio of inclusive jet (left) and dijet (right) cross sections to the theoretical prediction using the central value of the NNPDF2.1 PDF set for the last twojyj and jyjmax bins, respectively. The solid histograms show the ratio of the cross sections calculated with the other PDF sets to that calculated with NNPDF2.1. The experimental and theoretical systematic uncertainties are represented by the continuous and hatched bands, respectively.
uncertainty ranges from 5% to 10% for jyj < 1:5 but in-creases to 40% for the outer jyj bins and for high dijet masses and jet pT. Overall, the PDF uncertainty is dominant for the high pTand high dijet mass regions. Figure6shows the effect of the systematic uncertainties for the two observ-ables in all rapidity bins and for the NNPDF2.1 PDF set.
C. Nonperturbative corrections
The nonperturbative effects are estimated from the simulation, using the event generators PYTHIA6(tune Z2) andHERWIG++2.4.2 [25]. (ThePYTHIA6Z2 tune is identical to the Z1 tune described in [26] except that Z2 uses the CTEQ6L PDF while Z1 uses CTEQ5L.) These models are representative of the possible values of the nonperturbative corrections, due to their different physics descriptions. The nonperturbative correction is defined as the ratio of the cross section predicted with the nominal generator settings divided by the cross section predicted with the MPI and hadronization switched off. The central value of the non-perturbative correction is calculated from the average of the two models considered, and ranges from 1% to 20%, being larger in the dijet spectrum because of the involve-ment of lower pTjets.
VII. RESULTS
The unfolded inclusive jet and dijet spectra are shown in Fig.7, compared to the theoretical predictions.
To compare the CMS data and the theoretical prediction, the ratio of the two is taken. Figures8and9show this ratio using the central value of the NNPDF2.1 PDF set, accom-panied by the total experimental and theoretical uncertain-ties. The theoretical uncertainties vary considerably among the different PDF sets, and, in particular, in the high-pTand high-Mjj region. The experimental uncertainty is compa-rable to the theoretical uncertainty. The additional curves represent the ratio of the central values of the other PDF sets to NNPDF2.1. Agreement is observed between data and theory in all rapidity bins, given the statistical and systematic uncertainties, with the various theoretical pre-dictions showing differences of the order of 10%.
VIII. SUMMARY
Measurements of the double-differential inclusive jet and dijet cross sections are presented using 5:0 fb1 of data collected with the CMS detector in proton-proton collisions at pffiffiffis¼ 7 TeV. The measurements cover the jet pT range from 0.1 to 2 TeV, and the dijet mass range from 0.3 to 5 TeV in five rapidity bins up tojyj ¼ 2:5. The measured cross sections agree with the predictions of perturbative QCD at next-to-leading order obtained with five different PDF sets. Theoretical and experimental un-certainties are comparable, even at the limits of the experi-mental phase space, so these results may be used to constrain global PDF fits.
ACKNOWLEDGMENTS
We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid for delivering so effec-tively the computing infrastructure essential to our analy-ses. 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 and Research; the Belgian Fonds de la Recherche Scientifique, and Fonds voor Wetenschappelijk Onderzoek; the Brazilian Funding Agencies (CNPq, CAPES, FAPERJ, and FAPESP); the Bulgarian Ministry of Education, Youth 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; the Research Promotion Foundation, Cyprus; the Ministry of Education and Research, Recurrent financing contract SF0690030s09 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 Nucle´aire et de Physique des Particules/CNRS, and Commissariat a` l’E´ nergie Atomique et aux E´ nergies Alternatives/CEA, France; the Bundesministerium fu¨r Bildung und Forschung, Deutsche Forschungsgemeinschaft, and Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany; the General Secretariat for Research and Technology, Greece; the National Scientific Research Foundation, and National Office for Research and Technology, 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 Korean Ministry of Education, Science and Technology and the World Class University program of NRF, Republic of Korea; the Lithuanian Academy of Sciences; the Mexican Funding Agencies (CINVESTAV, CONACYT, SEP, and UASLP-FAI); the Ministry of Science and Innovation, New Zealand; the Pakistan Atomic Energy Commission; the Ministry of Science and Higher Education and the National Science Centre, Poland; the Fundac¸a˜o para a Cieˆncia e a Tecnologia, Portugal; JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); 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 Science and
Technological Development of Serbia; the Secretarı´a de Estado de Investigacio´n, Desarrollo e Innovacio´n and Programa Consolider-Ingenio 2010, Spain; the Swiss Funding Agencies (ETH Board, ETH Zurich, PSI, SNF, UniZH, Canton Zurich, and SER); the National Science Council, Taipei; the Thailand Center of Excellence in Physics, the Institute for the Promotion of Teaching Science and Technology of Thailand and the National Science and Technology Development Agency of Thailand; the Scientific and Technical Research Council of Turkey, and Turkish Atomic Energy Authority; the Science and Technology Facilities Council, U.K.; the U.S. Department of Energy, and the U.S. National Science Foundation. Individuals have received support
from the Marie-Curie program and the European Research Council (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; 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 Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo (Torino); and the HOMING PLUS program of Foundation for Polish Science, cofi-nanced from European Union, Regional Development Fund.
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T. Schum,38M. Seidel,38J. Sibille,38,rV. Sola,38H. Stadie,38G. Steinbru¨ck,38J. Thomsen,38L. Vanelderen,38 C. Barth,39J. Berger,39C. Bo¨ser,39T. Chwalek,39W. De Boer,39A. Descroix,39A. Dierlamm,39M. Feindt,39 M. Guthoff,39,eC. Hackstein,39F. Hartmann,39,eT. Hauth,39,eM. Heinrich,39H. Held,39K. H. Hoffmann,39 U. Husemann,39I. Katkov,39,pJ. R. Komaragiri,39P. Lobelle Pardo,39D. Martschei,39S. Mueller,39Th. Mu¨ller,39
M. Niegel,39A. Nu¨rnberg,39O. Oberst,39A. Oehler,39J. Ott,39G. Quast,39K. Rabbertz,39F. Ratnikov,39 N. Ratnikova,39S. Ro¨cker,39F.-P. Schilling,39G. Schott,39H. J. Simonis,39F. M. Stober,39D. Troendle,39R. Ulrich,39
J. Wagner-Kuhr,39S. Wayand,39T. Weiler,39M. Zeise,39G. Anagnostou,40G. Daskalakis,40T. Geralis,40 S. Kesisoglou,40A. Kyriakis,40D. Loukas,40I. Manolakos,40A. Markou,40C. Markou,40C. Mavrommatis,40 E. Ntomari,40L. Gouskos,41T. J. Mertzimekis,41A. Panagiotou,41N. Saoulidou,41I. Evangelou,42C. Foudas,42 P. Kokkas,42N. Manthos,42I. Papadopoulos,42V. Patras,42G. Bencze,43C. Hajdu,43P. Hidas,43D. Horvath,43,s F. Sikler,43V. Veszpremi,43G. Vesztergombi,43,tN. Beni,44S. Czellar,44J. Molnar,44J. Palinkas,44Z. Szillasi,44
J. Karancsi,45P. Raics,45Z. L. Trocsanyi,45B. Ujvari,45S. B. Beri,46V. Bhatnagar,46N. Dhingra,46R. Gupta,46 M. Kaur,46M. Z. Mehta,46N. Nishu,46L. K. Saini,46A. Sharma,46J. B. Singh,46Ashok Kumar,47Arun Kumar,47
S. Ahuja,47A. Bhardwaj,47B. C. Choudhary,47S. Malhotra,47M. Naimuddin,47K. Ranjan,47V. Sharma,47 R. K. Shivpuri,47S. Banerjee,48S. Bhattacharya,48S. Dutta,48B. Gomber,48Sa. Jain,48Sh. Jain,48R. Khurana,48 S. Sarkar,48M. Sharan,48A. Abdulsalam,49D. Dutta,49S. Kailas,49V. Kumar,49A. K. Mohanty,49,eL. M. Pant,49 P. Shukla,49T. Aziz,50S. Ganguly,50M. Guchait,50,uA. Gurtu,50,vM. Maity,50,wG. Majumder,50K. Mazumdar,50
G. B. Mohanty,50B. Parida,50K. Sudhakar,50N. Wickramage,50S. Banerjee,51S. Dugad,51H. Arfaei,52,x H. Bakhshiansohi,52S. M. Etesami,52,yA. Fahim,52,xM. Hashemi,52,zH. Hesari,52A. Jafari,52M. Khakzad,52 M. Mohammadi Najafabadi,52S. Paktinat Mehdiabadi,52B. Safarzadeh,52,aaM. Zeinali,52M. Abbrescia,53a,53b L. Barbone,53a,53bC. Calabria,53a,53b,eS. S. Chhibra,53a,53bA. Colaleo,53aD. Creanza,53a,53cN. De Filippis,53a,53c,e
M. De Palma,53a,53bL. Fiore,53aG. Iaselli,53a,53cG. Maggi,53a,53cM. Maggi,53aB. Marangelli,53a,53bS. My,53a,53c S. Nuzzo,53a,53bN. Pacifico,53aA. Pompili,53a,53bG. Pugliese,53a,53cG. Selvaggi,53a,53bL. Silvestris,53a
G. Singh,53a,53bR. Venditti,53a,53bP. Verwilligen,53aG. Zito,53aG. Abbiendi,54aA. C. Benvenuti,54a D. Bonacorsi,54a,54bS. Braibant-Giacomelli,54a,54bL. Brigliadori,54a,54bP. Capiluppi,54a,54bA. Castro,54a,54b
F. R. Cavallo,54aM. Cuffiani,54a,54bG. M. Dallavalle,54aF. Fabbri,54aA. Fanfani,54a,54bD. Fasanella,54a,54b P. Giacomelli,54aC. Grandi,54aL. Guiducci,54a,54bS. Marcellini,54aG. Masetti,54aM. Meneghelli,54a,54b,e A. Montanari,54aF. L. Navarria,54a,54bF. Odorici,54aA. Perrotta,54aF. Primavera,54a,54bA. M. Rossi,54a,54b
T. Rovelli,54a,54bG. P. Siroli,54a,54bN. Tosi,54aR. Travaglini,54a,54bS. Albergo,55a,55bG. Cappello,55a,55b M. Chiorboli,55a,55bS. Costa,55a,55bR. Potenza,55a,55bA. Tricomi,55a,55bC. Tuve,55a,55bG. Barbagli,56a V. Ciulli,56a,56bC. Civinini,56aR. D’Alessandro,56a,56bE. Focardi,56a,56bS. Frosali,56a,56bE. Gallo,56aS. Gonzi,56a,56b M. Meschini,56aS. Paoletti,56aG. Sguazzoni,56aA. Tropiano,56a,56bL. Benussi,57S. Bianco,57S. Colafranceschi,57,bb
F. Fabbri,57D. Piccolo,57P. Fabbricatore,58aR. Musenich,58aS. Tosi,58a,58bA. Benaglia,59aF. De Guio,59a,59b L. Di Matteo,59a,59b,eS. Fiorendi,59a,59bS. Gennai,59a,eA. Ghezzi,59a,59bS. Malvezzi,59aR. A. Manzoni,59a,59b
A. Martelli,59a,59bA. Massironi,59a,59bD. Menasce,59aL. Moroni,59aM. Paganoni,59a,59bD. Pedrini,59a S. Ragazzi,59a,59bN. Redaelli,59aS. Sala,59aT. Tabarelli de Fatis,59a,59bS. Buontempo,60aC. A. Carrillo Montoya,60a
N. Cavallo,60a,60cA. De Cosa,60a,60b,eO. Dogangun,60a,60bF. Fabozzi,60a,60cA. O. M. Iorio,60a,60bL. Lista,60a S. Meola,60a,60d,ccM. Merola,60aP. Paolucci,60a,eP. Azzi,61aN. Bacchetta,61a,eD. Bisello,61a,61bA. Branca,61a,61b,e
R. Carlin,61a,61bP. Checchia,61aT. Dorigo,61aF. Gasparini,61a,61bU. Gasparini,61a,61bA. Gozzelino,61a K. Kanishchev,61a,61cS. Lacaprara,61aI. Lazzizzera,61a,61cM. Margoni,61a,61bA. T. Meneguzzo,61a,61b J. Pazzini,61a,61bN. Pozzobon,61a,61bP. Ronchese,61a,61bM. Sgaravatto,61aF. Simonetto,61a,61bE. Torassa,61a
M. Tosi,61a,61bS. Vanini,61a,61bP. Zotto,61a,61bG. Zumerle,61a,61bM. Gabusi,62a,62bS. P. Ratti,62a,62b C. Riccardi,62a,62bP. Torre,62a,62bP. Vitulo,62a,62bM. Biasini,63a,63bG. M. Bilei,63aL. Fano`,63a,63bP. Lariccia,63a,63b
G. Mantovani,63a,63bM. Menichelli,63aA. Nappi,63a,63b,aF. Romeo,63a,63bA. Saha,63aA. Santocchia,63a,63b A. Spiezia,63a,63bS. Taroni,63a,63bP. Azzurri,64a,64cG. Bagliesi,64aJ. Bernardini,64aT. Boccali,64aG. Broccolo,64a,64c
R. Castaldi,64aR. T. D’Agnolo,64a,64c,eR. Dell’Orso,64aF. Fiori,64a,64b,eL. Foa`,64a,64cA. Giassi,64aA. Kraan,64a F. Ligabue,64a,64cT. Lomtadze,64aL. Martini,64a,ddA. Messineo,64a,64bF. Palla,64aA. Rizzi,64a,64bA. T. Serban,64a,ee P. Spagnolo,64aP. Squillacioti,64a,eR. Tenchini,64aG. Tonelli,64a,64bA. Venturi,64aP. G. Verdini,64aL. Barone,65a,65b
F. Cavallari,65aD. Del Re,65a,65bM. Diemoz,65aC. Fanelli,65a,65bM. Grassi,65a,65b,eE. Longo,65a,65bP. Meridiani,65a,e F. Micheli,65a,65bS. Nourbakhsh,65a,65bG. Organtini,65a,65bR. Paramatti,65aS. Rahatlou,65a,65bM. Sigamani,65a
L. Soffi,65a,65bN. Amapane,66a,66bR. Arcidiacono,66a,66cS. Argiro,66a,66bM. Arneodo,66a,66cC. Biino,66a N. Cartiglia,66aS. Casasso,66a,66bM. Costa,66a,66bN. Demaria,66aC. Mariotti,66a,eS. Maselli,66aE. Migliore,66a,66b
V. Monaco,66a,66bM. Musich,66a,eM. M. Obertino,66a,66cN. Pastrone,66aM. Pelliccioni,66aA. Potenza,66a,66b A. Romero,66a,66bM. Ruspa,66a,66cR. Sacchi,66a,66bA. Solano,66a,66bA. Staiano,66aS. Belforte,67a V. Candelise,67a,67bM. Casarsa,67aF. Cossutti,67aG. Della Ricca,67a,67bB. Gobbo,67aM. Marone,67a,67b,e D. Montanino,67a,67b,eA. Penzo,67aA. Schizzi,67a,67bT. Y. Kim,68S. K. Nam,68S. Chang,69D. H. Kim,69 G. N. Kim,69D. J. Kong,69H. Park,69D. C. Son,69T. Son,69J. Y. Kim,70Zero J. Kim,70S. Song,70S. Choi,71
D. Gyun,71B. Hong,71M. Jo,71H. Kim,71T. J. Kim,71K. S. Lee,71D. H. Moon,71S. K. Park,71M. Choi,72 J. H. Kim,72C. Park,72I. C. Park,72S. Park,72G. Ryu,72Y. Choi,73Y. K. Choi,73J. Goh,73M. S. Kim,73E. Kwon,73
B. Lee,73J. Lee,73S. Lee,73H. Seo,73I. Yu,73M. J. Bilinskas,74I. Grigelionis,74M. Janulis,74A. Juodagalvis,74 H. Castilla-Valdez,75E. De La Cruz-Burelo,75I. Heredia-de La Cruz,75R. Lopez-Fernandez,75J. Martı´nez-Ortega,75
A. Sanchez-Hernandez,75L. M. Villasenor-Cendejas,75S. Carrillo Moreno,76F. Vazquez Valencia,76 H. A. Salazar Ibarguen,77E. Casimiro Linares,78A. Morelos Pineda,78M. A. Reyes-Santos,78D. Krofcheck,79 A. J. Bell,80P. H. Butler,80R. Doesburg,80S. Reucroft,80H. Silverwood,80M. Ahmad,81M. I. Asghar,81J. Butt,81 H. R. Hoorani,81S. Khalid,81W. A. Khan,81T. Khurshid,81S. Qazi,81M. A. Shah,81M. Shoaib,81H. Bialkowska,82 B. Boimska,82T. Frueboes,82M. Go´rski,82M. Kazana,82K. Nawrocki,82K. Romanowska-Rybinska,82M. Szleper,82
G. Wrochna,82P. Zalewski,82G. Brona,83K. Bunkowski,83M. Cwiok,83W. Dominik,83K. Doroba,83 A. Kalinowski,83M. Konecki,83J. Krolikowski,83M. Misiura,83N. Almeida,84P. Bargassa,84A. David,84
P. Faccioli,84P. G. Ferreira Parracho,84M. Gallinaro,84J. Seixas,84J. Varela,84P. Vischia,84P. Bunin,85 M. Gavrilenko,85I. Golutvin,85I. Gorbunov,85V. Karjavin,85V. Konoplyanikov,85G. Kozlov,85A. Lanev,85 A. Malakhov,85P. Moisenz,85V. Palichik,85V. Perelygin,85S. Shmatov,85S. Shulha,85V. Smirnov,85A. Volodko,85 A. Zarubin,85S. Evstyukhin,86V. Golovtsov,86Y. Ivanov,86V. Kim,86P. Levchenko,86V. Murzin,86V. Oreshkin,86
I. Smirnov,86V. Sulimov,86L. Uvarov,86S. Vavilov,86A. Vorobyev,86An. Vorobyev,86Yu. Andreev,87 A. Dermenev,87S. Gninenko,87N. Golubev,87M. Kirsanov,87N. Krasnikov,87V. Matveev,87A. Pashenkov,87 D. Tlisov,87A. Toropin,87V. Epshteyn,88M. Erofeeva,88V. Gavrilov,88M. Kossov,88N. Lychkovskaya,88V. Popov,88
G. Safronov,88S. Semenov,88I. Shreyber,88V. Stolin,88E. Vlasov,88A. Zhokin,88A. Belyaev,89E. Boos,89 M. Dubinin,89,dL. Dudko,89A. Ershov,89A. Gribushin,89V. Klyukhin,89O. Kodolova,89I. Lokhtin,89A. Markina,89
S. Obraztsov,89M. Perfilov,89S. Petrushanko,89A. Popov,89L. Sarycheva,89,aV. Savrin,89A. Snigirev,89 V. Andreev,90M. Azarkin,90I. Dremin,90M. Kirakosyan,90A. Leonidov,90G. Mesyats,90S. V. Rusakov,90 A. Vinogradov,90I. Azhgirey,91I. Bayshev,91S. Bitioukov,91V. Grishin,91,eV. Kachanov,91D. Konstantinov,91 V. Krychkine,91V. Petrov,91R. Ryutin,91A. Sobol,91L. Tourtchanovitch,91S. Troshin,91N. Tyurin,91A. Uzunian,91
A. Volkov,91P. Adzic,92,ffM. Djordjevic,92M. Ekmedzic,92D. Krpic,92,ffJ. Milosevic,92M. Aguilar-Benitez,93 J. Alcaraz Maestre,93P. Arce,93C. Battilana,93E. Calvo,93M. Cerrada,93M. Chamizo Llatas,93N. Colino,93 B. De La Cruz,93A. Delgado Peris,93D. Domı´nguez Va´zquez,93C. Fernandez Bedoya,93J. P. Ferna´ndez Ramos,93 A. Ferrando,93J. Flix,93M. C. Fouz,93P. Garcia-Abia,93O. Gonzalez Lopez,93S. Goy Lopez,93J. M. Hernandez,93 M. I. Josa,93G. Merino,93J. Puerta Pelayo,93A. Quintario Olmeda,93I. Redondo,93L. Romero,93J. Santaolalla,93
M. S. Soares,93C. Willmott,93C. Albajar,94G. Codispoti,94J. F. de Troco´niz,94H. Brun,95J. Cuevas,95 J. Fernandez Menendez,95S. Folgueras,95I. Gonzalez Caballero,95L. Lloret Iglesias,95J. Piedra Gomez,95 J. A. Brochero Cifuentes,96I. J. Cabrillo,96A. Calderon,96S. H. Chuang,96J. Duarte Campderros,96M. Felcini,96,gg
M. Fernandez,96G. Gomez,96J. Gonzalez Sanchez,96A. Graziano,96C. Jorda,96A. Lopez Virto,96J. Marco,96 R. Marco,96C. Martinez Rivero,96F. Matorras,96F. J. Munoz Sanchez,96T. Rodrigo,96A. Y. Rodrı´guez-Marrero,96
A. Ruiz-Jimeno,96L. Scodellaro,96I. Vila,96R. Vilar Cortabitarte,96D. Abbaneo,97E. Auffray,97G. Auzinger,97 M. Bachtis,97P. Baillon,97A. H. Ball,97D. Barney,97J. F. Benitez,97C. Bernet,97,fG. Bianchi,97P. Bloch,97
A. Bocci,97A. Bonato,97C. Botta,97H. Breuker,97T. Camporesi,97G. Cerminara,97T. Christiansen,97 J. A. Coarasa Perez,97D. D’Enterria,97A. Dabrowski,97A. De Roeck,97S. Di Guida,97M. Dobson,97 N. Dupont-Sagorin,97A. Elliott-Peisert,97B. Frisch,97W. Funk,97G. Georgiou,97M. Giffels,97D. Gigi,97K. Gill,97
D. Giordano,97M. Girone,97M. Giunta,97F. Glege,97R. Gomez-Reino Garrido,97P. Govoni,97S. Gowdy,97 R. Guida,97S. Gundacker,97M. Hansen,97P. Harris,97C. Hartl,97J. Harvey,97B. Hegner,97A. Hinzmann,97 V. Innocente,97P. Janot,97K. Kaadze,97E. Karavakis,97K. Kousouris,97P. Lecoq,97Y.-J. Lee,97P. Lenzi,97
C. Lourenc¸o,97N. Magini,97T. Ma¨ki,97M. Malberti,97L. Malgeri,97M. Mannelli,97L. Masetti,97F. Meijers,97 S. Mersi,97E. Meschi,97R. Moser,97M. U. Mozer,97M. Mulders,97P. Musella,97E. Nesvold,97T. Orimoto,97 L. Orsini,97E. Palencia Cortezon,97E. Perez,97L. Perrozzi,97A. Petrilli,97A. Pfeiffer,97M. Pierini,97M. Pimia¨,97
D. Piparo,97G. Polese,97L. Quertenmont,97A. Racz,97W. Reece,97J. Rodrigues Antunes,97J. Rojo,97 G. Rolandi,97,hhC. Rovelli,97,iiM. Rovere,97H. Sakulin,97F. Santanastasio,97C. Scha¨fer,97C. Schwick,97 I. Segoni,97S. Sekmen,97A. Sharma,97P. Siegrist,97P. Silva,97M. Simon,97P. Sphicas,97,jjD. Spiga,97A. Tsirou,97
G. I. Veres,97,tJ. R. Vlimant,97H. K. Wo¨hri,97S. D. Worm,97,kkW. D. Zeuner,97W. Bertl,98K. Deiters,98 W. Erdmann,98K. Gabathuler,98R. Horisberger,98Q. Ingram,98H. C. Kaestli,98S. Ko¨nig,98D. Kotlinski,98 U. Langenegger,98F. Meier,98D. Renker,98T. Rohe,98L. Ba¨ni,99P. Bortignon,99M. A. Buchmann,99B. Casal,99
N. Chanon,99A. Deisher,99G. Dissertori,99M. Dittmar,99M. Donega`,99M. Du¨nser,99J. Eugster,99 K. Freudenreich,99C. Grab,99D. Hits,99P. Lecomte,99W. Lustermann,99A. C. Marini,99
P. Martinez Ruiz del Arbol,99N. Mohr,99F. Moortgat,99C. Na¨geli,99,llP. Nef,99F. Nessi-Tedaldi,99F. Pandolfi,99 L. Pape,99F. Pauss,99M. Peruzzi,99F. J. Ronga,99M. Rossini,99L. Sala,99A. K. Sanchez,99A. Starodumov,99,mm B. Stieger,99M. Takahashi,99L. Tauscher,99,aA. Thea,99K. Theofilatos,99D. Treille,99C. Urscheler,99R. Wallny,99
H. A. Weber,99L. Wehrli,99C. Amsler,100,nnV. Chiochia,100S. De Visscher,100C. Favaro,100M. Ivova Rikova,100 B. Kilminster,100B. Millan Mejias,100P. Otiougova,100P. Robmann,100H. Snoek,100S. Tupputi,100M. Verzetti,100
Y. H. Chang,101K. H. Chen,101C. Ferro,101C. M. Kuo,101S. W. Li,101W. Lin,101Y. J. Lu,101A. P. Singh,101 R. Volpe,101S. S. Yu,101P. Bartalini,102P. Chang,102Y. H. Chang,102Y. W. Chang,102Y. Chao,102K. F. Chen,102 C. Dietz,102U. Grundler,102W.-S. Hou,102Y. Hsiung,102K. Y. Kao,102Y. J. Lei,102R.-S. Lu,102D. Majumder,102
E. Petrakou,102X. Shi,102J. G. Shiu,102Y. M. Tzeng,102X. Wan,102M. Wang,102B. Asavapibhop,103 N. Srimanobhas,103A. Adiguzel,104M. N. Bakirci,104,ooS. Cerci,104,ppC. Dozen,104I. Dumanoglu,104E. Eskut,104
S. Girgis,104G. Gokbulut,104E. Gurpinar,104I. Hos,104E. E. Kangal,104T. Karaman,104G. Karapinar,104,qq A. Kayis Topaksu,104G. Onengut,104K. Ozdemir,104S. Ozturk,104,rrA. Polatoz,104K. Sogut,104,ss D. Sunar Cerci,104,ppB. Tali,104,ppH. Topakli,104,ooL. N. Vergili,104M. Vergili,104I. V. Akin,105T. Aliev,105 B. Bilin,105S. Bilmis,105M. Deniz,105H. Gamsizkan,105A. M. Guler,105K. Ocalan,105A. Ozpineci,105M. Serin,105 R. Sever,105U. E. Surat,105M. Yalvac,105E. Yildirim,105M. Zeyrek,105E. Gu¨lmez,106B. Isildak,106,ttM. Kaya,106,uu
O. Kaya,106,uuS. Ozkorucuklu,106,vvN. Sonmez,106,wwK. Cankocak,107L. Levchuk,108J. J. Brooke,109 E. Clement,109D. Cussans,109H. Flacher,109R. Frazier,109J. Goldstein,109M. Grimes,109G. P. Heath,109 H. F. Heath,109L. Kreczko,109S. Metson,109D. M. Newbold,109,kkK. Nirunpong,109A. Poll,109S. Senkin,109
V. J. Smith,109T. Williams,109L. Basso,110,xxK. W. Bell,110A. Belyaev,110,xxC. Brew,110R. M. Brown,110 D. J. A. Cockerill,110J. A. Coughlan,110K. Harder,110S. Harper,110J. Jackson,110B. W. Kennedy,110E. Olaiya,110
D. Petyt,110B. C. Radburn-Smith,110C. H. Shepherd-Themistocleous,110I. R. Tomalin,110W. J. Womersley,110 R. Bainbridge,111G. Ball,111R. Beuselinck,111O. Buchmuller,111D. Colling,111N. Cripps,111M. Cutajar,111
P. Dauncey,111G. Davies,111M. Della Negra,111W. Ferguson,111J. Fulcher,111D. Futyan,111A. Gilbert,111 A. Guneratne Bryer,111G. Hall,111Z. Hatherell,111J. Hays,111G. Iles,111M. Jarvis,111G. Karapostoli,111 L. Lyons,111A.-M. Magnan,111J. Marrouche,111B. Mathias,111R. Nandi,111J. Nash,111A. Nikitenko,111,mm A. Papageorgiou,111J. Pela,111M. Pesaresi,111K. Petridis,111M. Pioppi,111,yyD. M. Raymond,111S. Rogerson,111 A. Rose,111M. J. Ryan,111C. Seez,111P. Sharp,111,aA. Sparrow,111M. Stoye,111A. Tapper,111M. Vazquez Acosta,111
T. Virdee,111S. Wakefield,111N. Wardle,111T. Whyntie,111M. Chadwick,112J. E. Cole,112P. R. Hobson,112 A. Khan,112P. Kyberd,112D. Leggat,112D. Leslie,112W. Martin,112I. D. Reid,112P. Symonds,112L. Teodorescu,112
M. Turner,112K. Hatakeyama,113H. Liu,113T. Scarborough,113O. Charaf,114C. Henderson,114P. Rumerio,114 A. Avetisyan,115T. Bose,115C. Fantasia,115A. Heister,115J. St. John,115P. Lawson,115D. Lazic,115J. Rohlf,115
D. Sperka,115L. Sulak,115J. Alimena,116S. Bhattacharya,116G. Christopher,116D. Cutts,116Z. Demiragli,116 A. Ferapontov,116A. Garabedian,116U. Heintz,116S. Jabeen,116G. Kukartsev,116E. Laird,116G. Landsberg,116 M. Luk,116M. Narain,116D. Nguyen,116M. Segala,116T. Sinthuprasith,116T. Speer,116R. Breedon,117G. Breto,117
M. Calderon De La Barca Sanchez,117S. Chauhan,117M. Chertok,117J. Conway,117R. Conway,117P. T. Cox,117 J. Dolen,117R. Erbacher,117M. Gardner,117R. Houtz,117W. Ko,117A. Kopecky,117R. Lander,117O. Mall,117 T. Miceli,117D. Pellett,117F. Ricci-Tam,117B. Rutherford,117M. Searle,117J. Smith,117M. Squires,117M. Tripathi,117 R. Vasquez Sierra,117R. Yohay,117V. Andreev,118D. Cline,118R. Cousins,118J. Duris,118S. Erhan,118P. Everaerts,118 C. Farrell,118J. Hauser,118M. Ignatenko,118C. Jarvis,118G. Rakness,118P. Schlein,118,aP. Traczyk,118V. Valuev,118 M. Weber,118J. Babb,119R. Clare,119M. E. Dinardo,119J. Ellison,119J. W. Gary,119F. Giordano,119G. Hanson,119
H. Liu,119O. R. Long,119A. Luthra,119H. Nguyen,119S. Paramesvaran,119J. Sturdy,119S. Sumowidagdo,119 R. Wilken,119S. Wimpenny,119W. Andrews,120J. G. Branson,120G. B. Cerati,120S. Cittolin,120D. Evans,120 A. Holzner,120R. Kelley,120M. Lebourgeois,120J. Letts,120I. Macneill,120B. Mangano,120S. Padhi,120C. Palmer,120
G. Petrucciani,120M. Pieri,120M. Sani,120V. Sharma,120S. Simon,120E. Sudano,120M. Tadel,120Y. Tu,120 A. Vartak,120S. Wasserbaech,120,zzF. Wu¨rthwein,120A. Yagil,120J. Yoo,120D. Barge,121R. Bellan,121 C. Campagnari,121M. D’Alfonso,121T. Danielson,121K. Flowers,121P. Geffert,121F. Golf,121J. Incandela,121 C. Justus,121P. Kalavase,121D. Kovalskyi,121V. Krutelyov,121S. Lowette,121R. Magan˜a Villalba,121N. Mccoll,121
V. Pavlunin,121J. Ribnik,121J. Richman,121R. Rossin,121D. Stuart,121W. To,121C. West,121A. Apresyan,122 A. Bornheim,122Y. Chen,122E. Di Marco,122J. Duarte,122M. Gataullin,122Y. Ma,122A. Mott,122H. B. Newman,122
C. Rogan,122M. Spiropulu,122V. Timciuc,122J. Veverka,122R. Wilkinson,122S. Xie,122Y. Yang,122R. Y. Zhu,122 V. Azzolini,123A. Calamba,123R. Carroll,123T. Ferguson,123Y. Iiyama,123D. W. Jang,123Y. F. Liu,123M. Paulini,123
H. Vogel,123I. Vorobiev,123J. P. Cumalat,124B. R. Drell,124W. T. Ford,124A. Gaz,124E. Luiggi Lopez,124 J. G. Smith,124K. Stenson,124K. A. Ulmer,124S. R. Wagner,124J. Alexander,125A. Chatterjee,125N. Eggert,125
L. K. Gibbons,125B. Heltsley,125A. Khukhunaishvili,125B. Kreis,125N. Mirman,125G. Nicolas Kaufman,125 J. R. Patterson,125A. Ryd,125E. Salvati,125W. Sun,125W. D. Teo,125J. Thom,125J. Thompson,125J. Tucker,125 J. Vaughan,125Y. Weng,125L. Winstrom,125P. Wittich,125D. Winn,126S. Abdullin,127M. Albrow,127J. Anderson,127
L. A. T. Bauerdick,127A. Beretvas,127J. Berryhill,127P. C. Bhat,127K. Burkett,127J. N. Butler,127V. Chetluru,127 H. W. K. Cheung,127F. Chlebana,127V. D. Elvira,127I. Fisk,127J. Freeman,127Y. Gao,127D. Green,127O. Gutsche,127
J. Hanlon,127R. M. Harris,127J. Hirschauer,127B. Hooberman,127S. Jindariani,127M. Johnson,127U. Joshi,127 B. Klima,127S. Kunori,127S. Kwan,127C. Leonidopoulos,127,aaaJ. Linacre,127D. Lincoln,127R. Lipton,127 J. Lykken,127K. Maeshima,127J. M. Marraffino,127S. Maruyama,127D. Mason,127P. McBride,127K. Mishra,127 S. Mrenna,127Y. Musienko,127,bbbC. Newman-Holmes,127V. O’Dell,127O. Prokofyev,127E. Sexton-Kennedy,127
S. Sharma,127W. J. Spalding,127L. Spiegel,127L. Taylor,127S. Tkaczyk,127N. V. Tran,127L. Uplegger,127 E. W. Vaandering,127R. Vidal,127J. Whitmore,127W. Wu,127F. Yang,127J. C. Yun,127D. Acosta,128P. Avery,128
D. Bourilkov,128M. Chen,128T. Cheng,128S. Das,128M. De Gruttola,128G. P. Di Giovanni,128D. Dobur,128 A. Drozdetskiy,128R. D. Field,128M. Fisher,128Y. Fu,128I. K. Furic,128J. Gartner,128J. Hugon,128B. Kim,128
J. Konigsberg,128A. Korytov,128A. Kropivnitskaya,128T. Kypreos,128J. F. Low,128K. Matchev,128 P. Milenovic,128,cccG. Mitselmakher,128L. Muniz,128M. Park,128R. Remington,128A. Rinkevicius,128P. Sellers,128 N. Skhirtladze,128M. Snowball,128J. Yelton,128M. Zakaria,128V. Gaultney,129S. Hewamanage,129L. M. Lebolo,129
S. Linn,129P. Markowitz,129G. Martinez,129J. L. Rodriguez,129T. Adams,130A. Askew,130J. Bochenek,130 J. Chen,130B. Diamond,130S. V. Gleyzer,130J. Haas,130S. Hagopian,130V. Hagopian,130M. Jenkins,130 K. F. Johnson,130H. Prosper,130V. Veeraraghavan,130M. Weinberg,130M. M. Baarmand,131B. Dorney,131
M. Hohlmann,131H. Kalakhety,131I. Vodopiyanov,131F. Yumiceva,131M. R. Adams,132I. M. Anghel,132 L. Apanasevich,132Y. Bai,132V. E. Bazterra,132R. R. Betts,132I. Bucinskaite,132J. Callner,132R. Cavanaugh,132 O. Evdokimov,132L. Gauthier,132C. E. Gerber,132D. J. Hofman,132S. Khalatyan,132F. Lacroix,132C. O’Brien,132
C. Silkworth,132D. Strom,132P. Turner,132N. Varelas,132U. Akgun,133E. A. Albayrak,133B. Bilki,133,ddd W. Clarida,133F. Duru,133J.-P. Merlo,133H. Mermerkaya,133,eeeA. Mestvirishvili,133A. Moeller,133J. Nachtman,133
C. R. Newsom,133E. Norbeck,133Y. Onel,133F. Ozok,133,fffS. Sen,133P. Tan,133E. Tiras,133J. Wetzel,133 T. Yetkin,133K. Yi,133B. A. Barnett,134B. Blumenfeld,134S. Bolognesi,134D. Fehling,134G. Giurgiu,134 A. V. Gritsan,134Z. J. Guo,134G. Hu,134P. Maksimovic,134M. Swartz,134A. Whitbeck,134P. Baringer,135A. Bean,135
G. Benelli,135R. P. Kenny III,135M. Murray,135D. Noonan,135S. Sanders,135R. Stringer,135G. Tinti,135 J. S. Wood,135A. F. Barfuss,136T. Bolton,136I. Chakaberia,136A. Ivanov,136S. Khalil,136M. Makouski,136 Y. Maravin,136S. Shrestha,136I. Svintradze,136J. Gronberg,137D. Lange,137F. Rebassoo,137D. Wright,137 A. Baden,138B. Calvert,138S. C. Eno,138J. A. Gomez,138N. J. Hadley,138R. G. Kellogg,138M. Kirn,138
T. Kolberg,138Y. Lu,138M. Marionneau,138A. C. Mignerey,138K. Pedro,138A. Skuja,138J. Temple,138 M. B. Tonjes,138S. C. Tonwar,138A. Apyan,139G. Bauer,139J. Bendavid,139W. Busza,139E. Butz,139I. A. Cali,139
M. Chan,139V. Dutta,139G. Gomez Ceballos,139M. Goncharov,139Y. Kim,139M. Klute,139K. Krajczar,139,ggg A. Levin,139P. D. Luckey,139T. Ma,139S. Nahn,139C. Paus,139D. Ralph,139C. Roland,139G. Roland,139 M. Rudolph,139G. S. F. Stephans,139F. Sto¨ckli,139K. Sumorok,139K. Sung,139D. Velicanu,139E. A. Wenger,139 R. Wolf,139B. Wyslouch,139M. Yang,139Y. Yilmaz,139A. S. Yoon,139M. Zanetti,139V. Zhukova,139S. I. Cooper,140
B. Dahmes,140A. De Benedetti,140G. Franzoni,140A. Gude,140S. C. Kao,140K. Klapoetke,140Y. Kubota,140
J. Mans,140N. Pastika,140R. Rusack,140M. Sasseville,140A. Singovsky,140N. Tambe,140J. Turkewitz,140 L. M. Cremaldi,141R. Kroeger,141L. Perera,141R. Rahmat,141D. A. Sanders,141E. Avdeeva,142K. Bloom,142
S. Bose,142D. R. Claes,142A. Dominguez,142M. Eads,142J. Keller,142I. Kravchenko,142J. Lazo-Flores,142 S. Malik,142G. R. Snow,142A. Godshalk,143I. Iashvili,143S. Jain,143A. Kharchilava,143A. Kumar,143 S. Rappoccio,143G. Alverson,144E. Barberis,144D. Baumgartel,144M. Chasco,144J. Haley,144D. Nash,144 D. Trocino,144D. Wood,144J. Zhang,144A. Anastassov,145K. A. Hahn,145A. Kubik,145L. Lusito,145N. Mucia,145
N. Odell,145R. A. Ofierzynski,145B. Pollack,145A. Pozdnyakov,145M. Schmitt,145S. Stoynev,145M. Velasco,145 S. Won,145L. Antonelli,146D. Berry,146A. Brinkerhoff,146K. M. Chan,146M. Hildreth,146C. Jessop,146 D. J. Karmgard,146J. Kolb,146K. Lannon,146W. Luo,146S. Lynch,146N. Marinelli,146D. M. Morse,146T. Pearson,146 M. Planer,146R. Ruchti,146J. Slaunwhite,146N. Valls,146M. Wayne,146M. Wolf,146B. Bylsma,147L. S. Durkin,147 C. Hill,147R. Hughes,147K. Kotov,147T. Y. Ling,147D. Puigh,147M. Rodenburg,147C. Vuosalo,147G. Williams,147
B. L. Winer,147E. Berry,148P. Elmer,148V. Halyo,148P. Hebda,148J. Hegeman,148A. Hunt,148P. Jindal,148 S. A. Koay,148D. Lopes Pegna,148P. Lujan,148D. Marlow,148T. Medvedeva,148M. Mooney,148J. Olsen,148 P. Piroue´,148X. Quan,148A. Raval,148H. Saka,148D. Stickland,148C. Tully,148J. S. Werner,148A. Zuranski,148 E. Brownson,149A. Lopez,149H. Mendez,149J. E. Ramirez Vargas,149E. Alagoz,150V. E. Barnes,150D. Benedetti,150
G. Bolla,150D. Bortoletto,150M. De Mattia,150A. Everett,150Z. Hu,150M. Jones,150O. Koybasi,150M. Kress,150 A. T. Laasanen,150N. Leonardo,150V. Maroussov,150P. Merkel,150D. H. Miller,150N. Neumeister,150I. Shipsey,150 D. Silvers,150A. Svyatkovskiy,150M. Vidal Marono,150H. D. Yoo,150J. Zablocki,150Y. Zheng,150S. Guragain,151
N. Parashar,151A. Adair,152B. Akgun,152C. Boulahouache,152K. M. Ecklund,152F. J. M. Geurts,152W. Li,152 B. P. Padley,152R. Redjimi,152J. Roberts,152J. Zabel,152B. Betchart,153A. Bodek,153Y. S. Chung,153R. Covarelli,153
P. de Barbaro,153R. Demina,153Y. Eshaq,153T. Ferbel,153A. Garcia-Bellido,153P. Goldenzweig,153J. Han,153 A. Harel,153D. C. Miner,153D. Vishnevskiy,153M. Zielinski,153A. Bhatti,154R. Ciesielski,154L. Demortier,154
K. Goulianos,154G. Lungu,154S. Malik,154C. Mesropian,154S. Arora,155A. Barker,155J. P. Chou,155 C. Contreras-Campana,155E. Contreras-Campana,155D. Duggan,155D. Ferencek,155Y. Gershtein,155R. Gray,155 E. Halkiadakis,155D. Hidas,155A. Lath,155S. Panwalkar,155M. Park,155R. Patel,155V. Rekovic,155J. Robles,155 K. Rose,155S. Salur,155S. Schnetzer,155C. Seitz,155S. Somalwar,155R. Stone,155S. Thomas,155M. Walker,155
G. Cerizza,156M. Hollingsworth,156S. Spanier,156Z. C. Yang,156A. York,156R. Eusebi,157W. Flanagan,157 J. Gilmore,157T. Kamon,157,hhhV. Khotilovich,157R. Montalvo,157I. Osipenkov,157Y. Pakhotin,157A. Perloff,157
J. Roe,157A. Safonov,157T. Sakuma,157S. Sengupta,157I. Suarez,157A. Tatarinov,157D. Toback,157 N. Akchurin,158J. Damgov,158C. Dragoiu,158P. R. Dudero,158C. Jeong,158K. Kovitanggoon,158S. W. Lee,158 T. Libeiro,158Y. Roh,158I. Volobouev,158E. Appelt,159A. G. Delannoy,159C. Florez,159S. Greene,159A. Gurrola,159
W. Johns,159P. Kurt,159C. Maguire,159A. Melo,159M. Sharma,159P. Sheldon,159B. Snook,159S. Tuo,159 J. Velkovska,159M. W. Arenton,160M. Balazs,160S. Boutle,160B. Cox,160B. Francis,160J. Goodell,160R. Hirosky,160
A. Ledovskoy,160C. Lin,160C. Neu,160J. Wood,160S. Gollapinni,161R. Harr,161P. E. Karchin,161 C. Kottachchi Kankanamge Don,161P. Lamichhane,161A. Sakharov,161M. Anderson,162D. A. Belknap,162
L. Borrello,162D. Carlsmith,162M. Cepeda,162S. Dasu,162E. Friis,162L. Gray,162K. S. Grogg,162 M. Grothe,162R. Hall-Wilton,162M. Herndon,162A. Herve´,162P. Klabbers,162J. Klukas,162A. Lanaro,162 C. Lazaridis,162R. Loveless,162A. Mohapatra,162I. Ojalvo,162F. Palmonari,162G. A. Pierro,162I. Ross,162
A. Savin,162W. H. Smith,162and J. Swanson162 (CMS Collaboration)
1Yerevan Physics Institute, Yerevan, Armenia 2Institut fu¨r Hochenergiephysik der OeAW, Wien, Austria 3National Centre for Particle and High Energy Physics, Minsk, Belarus
4Universiteit Antwerpen, Antwerpen, Belgium 5Vrije Universiteit Brussel, Brussel, Belgium 6
Universite´ Libre de Bruxelles, Bruxelles, Belgium 7Ghent University, Ghent, Belgium
8Universite´ Catholique de Louvain, Louvain-la-Neuve, Belgium 9Universite´ de Mons, Mons, Belgium
10Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil 11Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
