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Rapidity distributions in exclusive Z þ jet and  þ jet events in pp collisions at

p

ffiffiffi

s

¼ 7 TeV

S. Chatrchyan et al.*

(CMS Collaboration)

(Received 11 October 2013; published 23 December 2013)

Rapidity distributions are presented for events containing either aZ boson or a photon with a single jet in proton-proton collisions produced at the CERN LHC. The data, collected with the CMS detector atffiffiffi

s p

¼ 7 TeV, correspond to an integrated luminosity of 5:0 fb1. The individual rapidity distributions of

the boson and the jet are consistent within 5% with expectations from perturbative QCD. However, QCD predictions for the sum and the difference in rapidities of the two final-state objects show discrepancies with CMS data. In particular, next-to-leading-order QCD calculations, and two common Monte Carlo event generators using different methods to match matrix-element partons with parton showers, appear inconsistent with the data as well as with each other.

DOI:10.1103/PhysRevD.88.112009 PACS numbers: 13.87.Ce, 12.38.Bx, 13.85.Qk, 14.70.Hp

From the time of Rutherford’s first scattering experi-ments, measuring angular distributions has provided a tool for understanding the structure and interactions of matter. Measurements of the rapidity distributions inV þ jet events, whereV refers either to a Z boson or a photon, can provide an important check of quantum chromodynam-ics (QCD) and event generators used to simulate elementary processes. ForZ boson decays into eþeorþ, trigger-ing is very efficient and nearly background-free, and from a theoretical point of view, the presence of the electroweak vertex makes the perturbative calculation of dynamical quantities even more robust. Since next-to-leading-order (NLO) perturbative QCD calculations are available for Z bosons produced in association with four or fewer jets [1], as well as for þ jet production [2–4], detailed comparison with data is possible. In addition, a precise understanding of these processes is also required in searches for new physics and in studies of the Higgs boson, for whichZ þ jets events constitute an important background.

The rapidity of a particle is defined asy ¼ ð1=2Þ ln ½ðE þ pzÞ=ðE  pzÞ, where E is the energy and pzis the

momen-tum component along the direction of the counterclockwise circulating proton beam. The invariant rapidity difference can be written in terms of the measured quantitiesyVandyjet as ydif ¼ jyV yjetj=2. The quantity ysum ¼ jyVþ yjetj=2 is the boost from the laboratory frame to the center-of-mass frame of theV and jet. In the laboratory frame, yVandyjet are highly correlated because V þ jet production usually involves a relatively high-momentum valence quark interacting with a low-momentum gluon or antiquark, which results in events where theV and jet are usually on the same end of the detector. The rapiditiesysumandydifare

effectively rotations in phase space of theyVandyjetsystem that yield two approximately uncorrelated quantities. The distribution inysumdepends mainly on the parton distribu-tion funcdistribu-tions (PDF), while the distribudistribu-tion inydif reflects the leading-order (LO) partonic differential cross section. Distributions in theysumandydifquantities were measured previously atpffiffiffis¼ 1:96 TeV by the D0 Collaboration [5]. Related angular quantities in V þ jet events have been measured at the LHC by CMS [6] and ATLAS [7–10]. In this paper, we compare theoretical predictions for normalized distributions in jyVj, jyjetj, ysum, andydif with data collected by the Compact Muon Solenoid (CMS) experiment.

The kinematic properties of Z þ jets events at the Tevatron [5] were found to be well described by the NLO

MCFM program [11,12]. For Z þ jets production at the

LHC, MCFMprovides predictions together with estimates of their uncertainties. For  þ jet events, the program developed by Owens [3] is used for NLO predictions and their uncertainties. This calculation employs fragmentation functions [4] to parametrize small-angle photon emission. Previous studies of the transverse momentum (pT) distri-butions of photons showed agreement between LHC data and a variety of QCD predictions [13–16]. In all MCFM

calculations, both the renormalization (R) and

factoriza-tion (F) scales are set to the invariant mass of the lepton

pair. For NLO prompt photon calculations, the scales are set to thepTof the photon.

Programs that use matrix-element descriptions of jet systems are accurate only when the partons have large transverse momentum or are well separated, while event generators using parton showers perform well in describing soft and small-angle radiation [17]. Hybrid methods are used to combine matrix-element prescriptions and parton showers to optimize performance for all regions of phase space. These programs generally proceed in three stages: (i) calculating the lowest-order ‘‘tree-level’’ contribution, (ii) simulating parton showering and clustering of final-state partons into jets, and (iii) employing one of two

*Full author list given at the end of the article.

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distri-bution of this work must maintain attridistri-bution to the author(s) and the published article’s title, journal citation, and DOI.

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schemes to minimize double counting of matrix-element jets and those produced by parton showering. The MLM [18] procedure rejects events when showering changes the event topology, while the CKKW method [19] uses a weighting scheme based on shower history. A previous comparison of hybrid methods [20] found large differences in distributions of ydif between the MLM and CKKW methods for W þ jet production. Hybrid models have been compared withV þ jet data at the Tevatron [5], where the CKKW method implemented inSHERPAprovided the best overall description of the observed distributions inysum andydif, but with a significantly different cross section. We also compare predictions from the two hybrid event gen-erators with our V þ jet data using MADGRAPH 5.1.1.0

[21], which implements the MLM scheme, and SHERPA 1.3.1[22], which uses the CKKW method. ForMADGRAPH, matching scales are chosen to be 20 GeV forZ bosons and 9–12 GeV for photons. Theffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi R and F scales are set to

m2 Zþ jetsp2T q and ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ðpTÞ2þ jetsp2T q

for Z bosons and photons, respectively, wheremZis the mass of theZ boson andpT is the photon transverse momentum. The PYTHIA

6.4.24 event generator is used for parton showers and ha-dronization [23]. For the SHERPA events, the matching scales are 20 and 10 GeV forZ bosons and photons, re-spectively. TheFandRscales are set tomZandpTforZ bosons and photons, respectively. The parton-shower moduleAPACIC++2.0[24] is used before thePYTHIA hadro-nization procedure. In our comparison, theSHERPA simula-tions use the NLO CTEQ6.6M [25] PDF. The use of different order PDF in hybrid calculations is disputed [26]: both LO and NLO PDF have been used in theory [20] and experiments [5,9]. To investigate this effect, the

MADGRAPH simulation is studied using both the LO and NLO CTEQ6 [27] PDF.

The central feature of the CMS apparatus is a super-conducting solenoid of 6 m internal diameter, providing a magnetic field of 3.8 T. A silicon pixel and strip tracker, a lead tungstate crystal electromagnetic calorimeter, and a brass/scintillator hadron calorimeter reside within the mag-netic field volume. Muons are detected in gas-ionization detectors embedded in the steel of the flux-return yoke of the magnet. In addition to the barrel and endcap detectors, CMS has extensive forward calorimetry. A more detailed description of CMS is given in Ref. [28]. A right-handed coordinate system is defined in CMS, with the origin at the center of the detector, thex axis pointing to the center of the LHC ring, and the y axis perpendicular to the plane of the LHC. The polar angle  is measured from the positivez axis and the azimuthal angle  is measured in thex-y plane in radians. Pseudorapidity, which is given by  ¼  ln ½tan ð=2Þ, is used for specifying acceptance requirements.

The data were collected during 2011 at app center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5:0  0:1 fb1 [29]. Because of limitations

in data handling, the triggers used for photon candidates had to be partially suppressed, and the effective luminosity for prompt photon production was 4:9  0:1 pb1. The multilevel trigger requires two electron or two muon candidates, with respective minimum-pTthresholds of 17 and 8 GeV, or 18 and 8 GeV, for the lepton of highest and next-highest pT. A photon candidate is required to have pT> 30 GeV.

Event reconstruction requires at least one vertex with jzj < 15 cm located within the beam pipe (radius <2 cm). Jets and leptons are reconstructed using the particle flow algorithm [30], which classifies all stable particles in an event using the full ensemble and redundancy of the CMS detector. Jets are clustered using the anti-kTalgorithm [31], with a distance parameter of 0.5, and are required to have jj < 2:4 to assure good tracker coverage. Jets, which have typical energy-scale uncertainties of <3% and resolution better than 10% [32], are required to havepT> 30 GeV. The difference between actual and simulated resolution is <1%, and simulations showed the difference has a negli-gible effect on the rapidity distributions. The energy of particles arising from additional overlapping pp interac-tions in the same bunch crossing, but not associated with the hard scattering, is referred to as ‘‘pileup.’’ Pileup from charged particles is subtracted based on tracking informa-tion from the other reconstructed vertices. Neutral particle pileup contributes 0:5 GeV to any jet for each additional pp interaction, and is subtracted from the jet energy. The probabilities of observing pileup from additional hard in-teractions or from double parton scattering are both<1% forV þ jet events [33,34]. Jets below threshold are ignored, and if any other jet exceeds threshold, the event is rejected. Reconstructed Z boson events are required to have at least two oppositely charged leptons of the same flavor (electrons or muons), each with pT> 20 GeV and jj < 2:1. The pair is required to have an invariant mass in the range of 76–106 GeV (close tomZ), andpT> 40 GeV. To include final-state radiation, the lepton energy is corrected by adding all photon energy deposited within an ð; Þ cone of R ¼pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiðÞ2þ ðÞ2¼ 0:1, centered on the

track direction. The relative isolation of a lepton is defined by the sum of the scalarpT of all reconstructed particles (excluding the lepton) within að; Þ cone of R ¼ 0:4 of the lepton direction, divided by the leptonpT. Electron and muon candidates are required to have an isolation of less than 20% and 15%, respectively. Leptons and jets are required to be separated by R > 0:5. Detailed discussions of electron and muon reconstruction at CMS can be found in Refs. [35–37]. Following these selections, theZ þ jet sample is 99% pure. The remaining contributions from tt pairs, diboson (ZZ, WW, or WZ), and multijet processes are negligible [38].

Reconstructed photon candidates are required to have pT> 40 GeV to assure a fully efficient trigger, and jj < 1:44 to avoid systematic effects associated with crossing

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calorimeter boundaries. Photons are reconstructed and se-lected as described in Ref. [13], using an isolation cone of R ¼ 0:4 in ð; Þ space. The isolation variables for photons are defined with the sum of the charged-particle scalarpTrequired to be less than 2 GeV, and the sums of the electromagnetic and hadron calorimeter contributions to be less than 4.2 and 2.2 GeV, respectively. The back-ground resulting from fragmentation of jets into collimated neutral mesons that mimic a photon is estimated using the ‘‘matrix’’ method of Ref. [38]. The transverse spatial dis-tribution of the energy in a cluster is used as a discriminant. Templates for the spatial transverse distributions of photon showers are taken fromPYTHIAevents, and reconstructed through the full CMS detector simulation viaGEANT4[39]. The templates for background are obtained from data using events passing all selection requirements, but with less stringent charged-particle isolation criteria (set between 2 and 5 GeV). Following the selection requirements, the fraction of photons in the sample is determined individually for each bin in ydif. The photon fraction decreases from ð61  2Þ% at ydif ¼ 0 to ð36  5Þ% at ydif ¼ 1:4, where the

uncertainties are statistical. To correct for background in theysum,jyjetj, and jyj distributions, events are weighted by the photon fractions as a function of ydif, while using the independence onysumto reduce point-to-point fluctua-tions. The resulting effective fractions (photon purities) change by less than 12% within the examined ranges of ysum,jyjetj, and jyj.

The reconstructed distributions are corrected for effi-ciency and resolution before determining the differential distributions in rapidity. ForZ þ jet events, efficiencies are evaluated from data and simulation using a ‘‘tag-and-probe’’ procedure introduced in Ref. [38]. The simulated spectra are scaled to match collision data as a function of the lepton pT and , and are then used to compute the efficiency as a function of the rapidity variables. Photon efficiencies are obtained from simulation, and rescaled using the measured electron efficiency, which is assumed to have the same  dependence as photons. All rapidity distributions are corrected for the effects of detector reso-lution using simulated events in an iterative unfolding method [40], as implemented in theROOUNFOLDpackage [41]. For all rapidity variables, the size of the correction is smaller than 1%. Only the distribution ofjyjetj has signifi-cant bin migration due to effects of resolution. The other variables have a correction factor consistent with unity.

The sources and relative experimental uncertainties in the rapidity distributions for the largesty values of binned rapidity for the three analyses are shown in TableI. The contributions include the uncertainty in jet energy scale, unfolding of rapidity distributions, and the scaling of si-mulated pileup interactions (corresponding to a 5% uncer-tainty in the total inelastic cross section). For Z þ jet production, the contributions to the relative experimental uncertainties also include the uncertainty in lepton

identification efficiency, dominated by the limited statisti-cal precision of simulated event samples, and the uncer-tainty in the background subtraction.

For photon production, bounds on the systematic uncer-tainty in the modeling of background are determined from the difference between data and the PYTHIAsimulation in two-jet events. The maximum extent of the ydif measure-ment for photon production is limited by the number of simulated events used to estimate the uncertainty from background. The systematic uncertainty in the photon background as a function of ydif varies between 2% and 11%, and is highly correlated across the range of ydif. There is also an uncorrelated uncertainty from the statisti-cal precision in the estimated background that is included in the ‘‘Statistical’’ row of TableI.

The best linear unbiased estimator (BLUE) [42,43] method is used to combine the corrected distributions for the electron and muon decay channels. A covariance matrix of 2N  2N dimensions, where 2 refers to the measure-ments for the electron and the muon channels andN is the number of bins, is ascribed to each distribution. The diago-nal variances represent the quadratic sum of both correlated and uncorrelated uncertainties. The off-diagonal elements are defined by 100% correlated uncertainties associated with the jet energy scale in the electron and muon channels. The size of the uncorrelated uncertainty in each bin is a factor of 3–5 times greater than the size of the correlated uncertainty.

The sources of theoretical uncertainty in all three analy-ses include the choice of PDF, the value of the strong coupling (s), and R and F. These are studied using

the MCFMand Owens calculations. The uncertainty in the PDF is obtained using the PDF4LHC [44] prescription.

TABLE I. Summary of the relative experimental uncertainties in the yields for the bins of largest jyj. At smaller jyj values, these uncertainties are in general smaller. The first three rows reflect uncertainties common to all three analyses. The following nine rows quantify the uncertainties by particle type according to (i) uncorrelated statistical uncertainty, (ii) trigger and selection efficiency, and (iii) correlated estimation of the background, separately foreþe,þ, and events.

Source jyVj (%) jyjetj (%) ysum(%) ydif (%)

Jet energy 0.4 0.6 0.3 0.4 Pileup reweight 0.5 0.1 0.3 0.1 Unfolding    5.0       e statistical 7.1 2.2 8.0 5.7 e efficiency 3.1 0.9 3.2 2.8 e background 0.2 0.2 0.2 0.2  statistical 6.3 1.9 6.1 4.6  efficiency 1.5 0.4 1.2 1.2  background 0.2 0.2 0.2 0.2  statistical 6.6 19 8.6 15  efficiency 0.4 0.6 0.4 1.0  background 7.0 2.0 1.0 11

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The baseline set of PDF is CTEQ6.6M, while the CT10 [45], MSTW2008 [46], and NNPDF21 [47] PDF are used as alternatives. For bothZ þ jet and  þ jet events, these alternatives correspond to<2% shift in all y distributions; however, using the LO rather than NLO parametrizations of PDF produces 10% difference in the ysum and jyVj distributions, whereas the ydif and jyjetj distributions are affected only slightly. Changes of s within the CT10

bounds cause<1% change in all variables. The theoretical uncertainty from the choice ofFandR is estimated by changing these scales up and down by a factor of 2. For Z þ jet and  þ jet events, the differences in the normal-ized distributions as a function ofysum,jyjetj, and jyVj are <2%, while the change in ydif is  8%. Moreover, the

changes are similar for both LO and NLO calculations, although the normalization factor can be quite different.

/d y σ dσ 1/ 0.00 0.05 0.10 0.15 Z + 1 jet CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) MCFM (NLO) -1 = 7 TeV, L = 5 fb s CMS, (a) | Z |y 0.0 0.5 1.0 1.5 2.0 Ratio to MCFM 0.8 0.9 1.0 1.1 1.2

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF) uncert. F µ and R µ MCFM MCFM PDF uncert. /d y σ dσ 1 / 0.00 0.05 0.10 Z + 1 jet CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) MCFM (NLO) -1 = 7 TeV, L = 5 fb s CMS, (b) | jet |y 0.0 0.5 1.0 1.5 2.0 Ratio to MCFM 0.8 0.9 1.0 1.1 1.2

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF) uncert. F µ and R µ MCFM MCFM PDF uncert. /d y σ dσ 1 / 0.00 0.05 0.10 0.15 Z + 1 jet CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) MCFM (NLO) -1 = 7 TeV, L = 5 fb s CMS, (c) sum y 0.0 0.5 1.0 1.5 2.0 Ratio to MCFM 0.6 0.8 1.0 1.2 1.4

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF) uncert. F µ and R µ MCFM MCFM PDF uncert. /dyσ dσ 1/ 0.0 0.1 0.2 0.3 Z + 1 jet CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) MCFM (NLO) -1 = 7 TeV, L = 5 fb s CMS, (d) dif y 0.0 0.5 1.0 1.5 Ratio to MCFM 0.5 1.0 1.5

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF) uncert. F µ and R µ MCFM MCFM PDF uncert.

FIG. 1 (color online). Distributions in absolute values of rapidities for (a) theZ boson, (b) the jet, (c) their sums, and (d) their differences, normalized to unity. The data are shown after correcting for efficiency and resolution, and displayed with statistical and systematic uncertainties combined in quadrature. The lower panel of each figure gives ratios of the data and simulations to the NLO calculation of MCFM. The ratio error bars include MCFM statistical uncertainties folded with data statistical and systematic uncertainties. Theoretical uncertainties in the MCFM calculations are shown as shaded areas representing variations ofR,F, and PDF. Statistical uncertainties for theMADGRAPHandSHERPApredictions are displayed as bands around the central values. The central value forMADGRAPHsimulations using LO PDF is depicted by a line. All other calculations use NLO versions of PDF.

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The NLO calculations do not include effects from final-state photon radiation, parton showering, and hadro-nization, since these are estimated as negligible using the

PYTHIAprogram.

The normalized rapidity distributions forjyZj, jyjetj, ydif, andysum, along with predictions from theory, are shown in Fig. 1for Z þ jet events. The data for the jyZj and jyjetj distributions agree to better than 5% accuracy with

SHERPA,MADGRAPH, andMCFMover the full range of the measurement. The SHERPAsimulation reproduces the fea-tures of theysumdistribution better than theMADGRAPHor MCFM programs. As shown in Fig. 1, when MADGRAPH

events are simulated using the LO PDF, the distributions ofysum andjyZj are less consistent with the data. The ydif distribution is consistent with MCFM for ydif< 1:0. As

was noted in Ref. [20], the two hybrid programs differ

/dyσ dσ 1/ 0.00 0.05 0.10 0.15 + 1 jet γ CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) Owens (NLO) (a) -1 = 7 TeV, L = 4.9 pb s CMS, | γ |y 0.0 0.5 1.0 Ratio to Owens 0.6 0.8 1.0 1.2 1.4 uncert. F µ and R µ Owens Owens PDF uncert.

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF) /dyσ dσ 1/ 0.00 0.05 0.10 0.15 + 1 jet γ CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) Owens (NLO) (b) -1 = 7 TeV, L = 4.9 pb s CMS, | jet |y 0.0 0.5 1.0 1.5 2.0 Ratio to Owens 0.6 0.8 1.0 1.2 1.4 uncert. F µ and R µ Owens Owens PDF uncert.

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF) /dyσ dσ 1/ 0.0 0.1 0.2 + 1 jet γ CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) Owens (NLO) (c) -1 = 7 TeV, L = 4.9 pb s CMS, sum y 0.0 0.5 1.0 Ratio to Owens 0.6 0.8 1.0 1.2 1.4 uncert. F µ and R µ Owens Owens PDF uncert.

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF) /dyσ dσ 1/ 0.0 0.1 0.2 0.3 + 1 jet γ CMS Data SHERPA (NLO PDF) MADGRAPH (NLO PDF) Owens (NLO) (d) -1 = 7 TeV, L = 4.9 pb s CMS, dif y 0.0 0.5 1.0 Ratio to Owens 0.6 0.8 1.0 1.2 1.4 uncert. F µ and R µ Owens Owens PDF uncert.

SHERPA with stat. uncert. MADGRAPH with stat. uncert. MADGRAPH (LO PDF)

-0.1

FIG. 2 (color online). Distributions in absolute values of rapidities for (a) the photon, (b) the jet, (c) their sums, and (d) their differences, normalized to unity. The data are shown after correcting for efficiency and resolution, and displayed with statistical and systematic uncertainties combined in quadrature. The lower panel of each figure gives ratios of the data and simulations to the NLO calculation of Owens. The ratio error bars include Owens statistical uncertainties folded with data statistical and systematic uncertainties. Theoretical uncertainties in the Owens calculations are shown as shaded areas representing variations ofR,F,

and PDF. Statistical uncertainties for theMADGRAPHandSHERPApredictions are displayed as bands around the central values. The central value forMADGRAPHsimulations using LO PDF is depicted by a line. All other calculations use NLO versions of PDF.

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considerably in the prediction for ydif. Since both

MADGRAPHandSHERPAuse the same LO matrix elements and approaches to parton showering, the difference in the distribution ofydif can be attributed to the matching algo-rithm, with the SHERPA CKKW scheme appearing more consistent with the data. Indeed, theMADGRAPHdistribution ofydifresembles the LO distribution. The difference inydif between the LO and NLO calculations is due to the con-tribution from NLO diagrams with a gluon propagator that yield more forward rapidities. The rapidity distributions for  þ jet events shown in Fig.2are consistent with perturba-tive QCD. The qualitaperturba-tive difference inydif for the hybrid generators MADGRAPH andSHERPA is comparable to that observed inZ þ jet events, although the statistical precision of the þ jet measurement is insufficient to discriminate between the theoretical alternatives.

In summary, the CMS detector was used to measure the rapidities of particles in events containing a vector (V) boson (either aZ boson or photon) in association with a single jet inpp collisions atpffiffiffis¼ 7 TeV for an integrated luminosity of 5:0 fb1. The rapidity distributions ofjyVj and jyjetj are found to agree with predictions from the

SHERPA,MADGRAPH, and MCFMQCD models. The distri-bution for the sum of theV and jet rapidities is described by all predictions to better than 5% precision forysum< 1:0, and is best described by hybrid calculations that employ NLO PDF. The distribution in the difference in rapidities (ydif) is described to better than 10% by theMCFM predic-tion. The two hybrid event generators differ by as much as  50% in their predictions for distributions in ydif, but SHERPA is significantly closer to data than MADGRAPH. Nevertheless, SHERPA overestimates the cross section at

higherydif. We attribute the difference between the hybrid event generator distributions to the respective methods by

which partons from matrix elements are matched to parton showers.

The authors thank J. Campbell, R. Frederix, and J. Owens for their substantial contributions to this work. 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 grate-fully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid for delivering so effectively 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 agen-cies: BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Republic of Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEPCenter, IPST and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA).

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S. Lacaprara,63aI. Lazzizzera,63a,63cM. Margoni,63a,63bA. T. Meneguzzo,63a,63bJ. Pazzini,63a,63bM. Pegoraro,63a N. Pozzobon,63a,63bP. Ronchese,63a,63bF. Simonetto,63a,63bE. Torassa,63aM. Tosi,63a,63bA. Triossi,63aS. Ventura,63a

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R. Arcidiacono,68a,68cS. Argiro,68a,68bM. Arneodo,68a,68cR. Bellan,68a,68bC. Biino,68aN. Cartiglia,68a S. Casasso,68a,68bM. Costa,68a,68bA. Degano,68a,68bN. Demaria,68aC. Mariotti,68aS. Maselli,68aE. Migliore,68a,68b

V. Monaco,68a,68bM. Musich,68aM. M. Obertino,68a,68cN. Pastrone,68aM. Pelliccioni,68a,cA. Potenza,68a,68b A. Romero,68a,68bM. Ruspa,68a,68cR. Sacchi,68a,68bA. Solano,68a,68bA. Staiano,68aU. Tamponi,68aS. Belforte,69a

V. Candelise,69a,69bM. Casarsa,69aF. Cossutti,69a,cG. Della Ricca,69a,69bB. Gobbo,69aC. La Licata,69a,69b M. Marone,69a,69bD. Montanino,69a,69bA. Penzo,69aA. Schizzi,69a,69bA. Zanetti,69aS. Chang,70T. Y. Kim,70 S. K. Nam,70D. H. Kim,71G. N. Kim,71J. E. Kim,71D. J. Kong,71Y. D. Oh,71H. Park,71D. C. Son,71J. Y. Kim,72 Zero J. Kim,72S. Song,72S. Choi,73D. Gyun,73B. Hong,73M. Jo,73H. Kim,73T. J. Kim,73K. S. Lee,73S. K. Park,73 Y. Roh,73M. Choi,74J. H. Kim,74C. Park,74I. C. Park,74S. Park,74G. Ryu,74Y. Choi,75Y. K. Choi,75J. Goh,75

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M. S. Kim,75E. Kwon,75B. Lee,75J. Lee,75S. Lee,75H. Seo,75I. Yu,75I. Grigelionis,76A. Juodagalvis,76 H. Castilla-Valdez,77E. De La Cruz-Burelo,77I. Heredia-de La Cruz,77,iiR. Lopez-Fernandez,77 J. Martı´nez-Ortega,77A. Sanchez-Hernandez,77L. M. Villasenor-Cendejas,77S. Carrillo Moreno,78 F. Vazquez Valencia,78H. A. Salazar Ibarguen,79E. Casimiro Linares,80A. Morelos Pineda,80M. A. Reyes-Santos,80

D. Krofcheck,81A. J. Bell,82P. H. Butler,82R. Doesburg,82S. Reucroft,82H. Silverwood,82M. Ahmad,83 M. I. Asghar,83J. Butt,83H. R. Hoorani,83S. Khalid,83W. A. Khan,83T. Khurshid,83S. Qazi,83M. A. Shah,83

M. Shoaib,83H. Bialkowska,84B. Boimska,84T. Frueboes,84M. Go´rski,84M. Kazana,84K. Nawrocki,84 K. Romanowska-Rybinska,84M. Szleper,84G. Wrochna,84P. Zalewski,84G. Brona,85K. Bunkowski,85M. Cwiok,85

W. Dominik,85K. Doroba,85A. Kalinowski,85M. Konecki,85J. Krolikowski,85M. Misiura,85W. Wolszczak,85 N. Almeida,86P. Bargassa,86C. Beira˜o Da Cruz E Silva,86P. Faccioli,86P. G. Ferreira Parracho,86M. Gallinaro,86

F. Nguyen,86J. Rodrigues Antunes,86J. Seixas,86,cJ. Varela,86P. Vischia,86S. Afanasiev,87P. Bunin,87 M. Gavrilenko,87I. Golutvin,87I. Gorbunov,87A. Kamenev,87V. Karjavin,87V. Konoplyanikov,87A. Lanev,87

A. Malakhov,87V. Matveev,87P. Moisenz,87V. Palichik,87V. Perelygin,87S. Shmatov,87N. Skatchkov,87 V. Smirnov,87A. Zarubin,87S. Evstyukhin,88V. Golovtsov,88Y. Ivanov,88V. Kim,88P. Levchenko,88V. Murzin,88 V. Oreshkin,88I. Smirnov,88V. Sulimov,88L. Uvarov,88S. Vavilov,88A. Vorobyev,88An. Vorobyev,88Yu. Andreev,89

A. Dermenev,89S. Gninenko,89N. Golubev,89M. Kirsanov,89N. Krasnikov,89A. Pashenkov,89D. Tlisov,89 A. Toropin,89V. Epshteyn,90M. Erofeeva,90V. Gavrilov,90N. Lychkovskaya,90V. Popov,90G. Safronov,90 S. Semenov,90A. Spiridonov,90V. Stolin,90E. Vlasov,90A. Zhokin,90V. Andreev,91M. Azarkin,91I. Dremin,91

M. Kirakosyan,91A. Leonidov,91G. Mesyats,91S. V. Rusakov,91A. Vinogradov,91A. Belyaev,92E. Boos,92 M. Dubinin,92,hL. Dudko,92A. Ershov,92A. Gribushin,92V. Klyukhin,92O. Kodolova,92I. Lokhtin,92A. Markina,92

S. Obraztsov,92S. Petrushanko,92V. Savrin,92A. Snigirev,92I. Azhgirey,93I. Bayshev,93S. Bitioukov,93 V. Kachanov,93A. Kalinin,93D. Konstantinov,93V. Krychkine,93V. Petrov,93R. Ryutin,93A. Sobol,93 L. Tourtchanovitch,93S. Troshin,93N. Tyurin,93A. Uzunian,93A. Volkov,93P. Adzic,94,jjM. Djordjevic,94 M. Ekmedzic,94D. Krpic,94,jjJ. Milosevic,94M. Aguilar-Benitez,95J. Alcaraz Maestre,95C. Battilana,95E. Calvo,95 M. Cerrada,95M. Chamizo Llatas,95,cN. Colino,95B. De La Cruz,95A. Delgado Peris,95D. Domı´nguez Va´zquez,95

C. Fernandez Bedoya,95J. P. Ferna´ndez Ramos,95A. Ferrando,95J. Flix,95M. C. Fouz,95P. Garcia-Abia,95 O. Gonzalez Lopez,95S. Goy Lopez,95J. M. Hernandez,95M. I. Josa,95G. Merino,95E. Navarro De Martino,95

J. Puerta Pelayo,95A. Quintario Olmeda,95I. Redondo,95L. Romero,95J. Santaolalla,95M. S. Soares,95 C. Willmott,95C. Albajar,96J. F. de Troco´niz,96H. Brun,97J. Cuevas,97J. Fernandez Menendez,97S. Folgueras,97

I. Gonzalez Caballero,97L. Lloret Iglesias,97J. Piedra Gomez,97J. A. Brochero Cifuentes,98I. J. Cabrillo,98 A. Calderon,98S. H. Chuang,98J. Duarte Campderros,98M. Fernandez,98G. Gomez,98J. Gonzalez Sanchez,98

A. Graziano,98C. Jorda,98A. Lopez Virto,98J. Marco,98R. Marco,98C. Martinez Rivero,98F. Matorras,98 F. J. Munoz Sanchez,98T. Rodrigo,98A. Y. Rodrı´guez-Marrero,98A. Ruiz-Jimeno,98L. Scodellaro,98I. Vila,98

R. Vilar Cortabitarte,98D. Abbaneo,99E. Auffray,99G. Auzinger,99M. Bachtis,99P. Baillon,99A. H. Ball,99 D. Barney,99J. Bendavid,99J. F. Benitez,99C. Bernet,99,iG. Bianchi,99P. Bloch,99A. Bocci,99A. Bonato,99 O. Bondu,99C. Botta,99H. Breuker,99T. Camporesi,99G. Cerminara,99T. Christiansen,99J. A. Coarasa Perez,99 S. Colafranceschi,99,kkD. d’Enterria,99A. Dabrowski,99A. David,99A. De Roeck,99S. De Visscher,99S. Di Guida,99

M. Dobson,99N. Dupont-Sagorin,99A. Elliott-Peisert,99J. Eugster,99W. Funk,99G. Georgiou,99M. Giffels,99 D. Gigi,99K. Gill,99D. Giordano,99M. Girone,99M. Giunta,99F. Glege,99R. Gomez-Reino Garrido,99S. Gowdy,99

R. Guida,99J. Hammer,99M. Hansen,99P. Harris,99C. Hartl,99A. Hinzmann,99V. Innocente,99P. Janot,99 E. Karavakis,99K. Kousouris,99K. Krajczar,99P. Lecoq,99Y.-J. Lee,99C. Lourenc¸o,99N. Magini,99M. Malberti,99

L. Malgeri,99M. Mannelli,99L. Masetti,99F. Meijers,99S. Mersi,99E. Meschi,99R. Moser,99M. Mulders,99 P. Musella,99E. Nesvold,99L. Orsini,99E. Palencia Cortezon,99E. Perez,99L. Perrozzi,99A. Petrilli,99A. Pfeiffer,99

M. Pierini,99M. Pimia¨,99D. Piparo,99M. Plagge,99L. Quertenmont,99A. Racz,99W. Reece,99G. Rolandi,99,ll M. Rovere,99H. Sakulin,99F. Santanastasio,99C. Scha¨fer,99C. Schwick,99I. Segoni,99S. Sekmen,99A. Sharma,99

P. Siegrist,99P. Silva,99M. Simon,99P. Sphicas,99,mmD. Spiga,99M. Stoye,99A. Tsirou,99G. I. Veres,99,v J. R. Vlimant,99H. K. Wo¨hri,99S. D. Worm,99,nnW. D. Zeuner,99W. Bertl,100K. Deiters,100W. Erdmann,100 K. Gabathuler,100R. Horisberger,100Q. Ingram,100H. C. Kaestli,100S. Ko¨nig,100D. Kotlinski,100U. Langenegger,100

D. Renker,100T. Rohe,100F. Bachmair,101L. Ba¨ni,101L. Bianchini,101P. Bortignon,101M. A. Buchmann,101 B. Casal,101N. Chanon,101A. Deisher,101G. Dissertori,101M. Dittmar,101M. Donega`,101M. Du¨nser,101P. Eller,101

K. Freudenreich,101C. Grab,101D. Hits,101P. Lecomte,101W. Lustermann,101B. Mangano,101A. C. Marini,101

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P. Martinez Ruiz del Arbol,101D. Meister,101N. Mohr,101F. Moortgat,101C. Na¨geli,101,ooP. Nef,101 F. Nessi-Tedaldi,101F. Pandolfi,101L. Pape,101F. Pauss,101M. Peruzzi,101F. J. Ronga,101M. Rossini,101L. Sala,101

A. K. Sanchez,101A. Starodumov,101,ppB. Stieger,101M. Takahashi,101L. Tauscher,101,aA. Thea,101 K. Theofilatos,101D. Treille,101C. Urscheler,101R. Wallny,101H. A. Weber,101C. Amsler,102,qqV. Chiochia,102

C. Favaro,102M. Ivova Rikova,102B. Kilminster,102B. Millan Mejias,102P. Otiougova,102P. Robmann,102 H. Snoek,102S. Taroni,102S. Tupputi,102M. Verzetti,102Y. Yang,102M. Cardaci,103Y. H. Chang,103K. H. Chen,103 C. Ferro,103C. M. Kuo,103S. W. Li,103W. Lin,103Y. J. Lu,103R. Volpe,103S. S. Yu,103P. Bartalini,104P. Chang,104 Y. H. Chang,104Y. W. Chang,104Y. Chao,104K. F. Chen,104C. Dietz,104U. Grundler,104W.-S. Hou,104Y. Hsiung,104 K. Y. Kao,104Y. J. Lei,104R.-S. Lu,104D. Majumder,104E. Petrakou,104X. Shi,104J. G. Shiu,104Y. M. Tzeng,104 M. Wang,104B. Asavapibhop,105N. Suwonjandee,105A. Adiguzel,106M. N. Bakirci,106,rrS. Cerci,106,ssC. Dozen,106

I. Dumanoglu,106E. Eskut,106S. Girgis,106G. Gokbulut,106E. Gurpinar,106I. Hos,106E. E. Kangal,106 A. Kayis Topaksu,106G. Onengut,106,ttK. Ozdemir,106S. Ozturk,106,rrA. Polatoz,106K. Sogut,106,uu D. Sunar Cerci,106,ssB. Tali,106,ssH. Topakli,106,rrM. Vergili,106I. V. Akin,107T. Aliev,107B. Bilin,107S. Bilmis,107

M. Deniz,107H. Gamsizkan,107A. M. Guler,107G. Karapinar,107,vvK. Ocalan,107A. Ozpineci,107M. Serin,107 R. Sever,107U. E. Surat,107M. Yalvac,107M. Zeyrek,107E. Gu¨lmez,108B. Isildak,108,wwM. Kaya,108,xxO. Kaya,108,xx

S. Ozkorucuklu,108,yyN. Sonmez,108,zzH. Bahtiyar,109,aaaE. Barlas,109K. Cankocak,109Y. O. Gu¨naydin,109,bbb F. I. Vardarl,109M. Yu¨cel,109L. Levchuk,110P. Sorokin,110J. J. Brooke,111E. Clement,111D. Cussans,111 H. Flacher,111R. Frazier,111J. Goldstein,111M. Grimes,111G. P. Heath,111H. F. Heath,111L. Kreczko,111 S. Metson,111D. M. Newbold,111,nnK. Nirunpong,111A. Poll,111S. Senkin,111V. J. Smith,111T. Williams,111 K. W. Bell,112A. Belyaev,112,cccC. Brew,112R. M. Brown,112D. J. A. Cockerill,112J. A. Coughlan,112K. Harder,112 S. Harper,112E. Olaiya,112D. Petyt,112B. C. Radburn-Smith,112C. H. Shepherd-Themistocleous,112I. R. Tomalin,112 W. J. Womersley,112R. Bainbridge,113O. Buchmuller,113D. Burton,113D. Colling,113N. Cripps,113M. Cutajar,113

P. Dauncey,113G. Davies,113M. Della Negra,113W. Ferguson,113J. Fulcher,113D. Futyan,113A. Gilbert,113 A. Guneratne Bryer,113G. Hall,113Z. Hatherell,113J. Hays,113G. Iles,113M. Jarvis,113G. Karapostoli,113 M. Kenzie,113R. Lane,113R. Lucas,113,nnL. Lyons,113A.-M. Magnan,113J. Marrouche,113B. Mathias,113 R. Nandi,113J. Nash,113A. Nikitenko,113,ppJ. Pela,113M. Pesaresi,113K. Petridis,113M. Pioppi,113,ddd D. M. Raymond,113S. Rogerson,113A. Rose,113C. Seez,113P. Sharp,113,aA. Sparrow,113A. Tapper,113 M. Vazquez Acosta,113T. Virdee,113S. Wakefield,113N. Wardle,113T. Whyntie,113M. Chadwick,114J. E. Cole,114 P. R. Hobson,114A. Khan,114P. Kyberd,114D. Leggat,114D. Leslie,114W. Martin,114I. D. Reid,114P. Symonds,114 L. Teodorescu,114M. Turner,114J. Dittmann,115K. Hatakeyama,115A. Kasmi,115H. Liu,115T. Scarborough,115

O. Charaf,116S. I. Cooper,116C. Henderson,116P. Rumerio,116A. Avetisyan,117T. Bose,117C. Fantasia,117 A. Heister,117P. Lawson,117D. Lazic,117J. Rohlf,117D. Sperka,117J. St. John,117L. Sulak,117J. Alimena,118

S. Bhattacharya,118G. Christopher,118D. Cutts,118Z. Demiragli,118A. Ferapontov,118A. Garabedian,118 U. Heintz,118S. Jabeen,118G. Kukartsev,118E. Laird,118G. Landsberg,118M. Luk,118M. Narain,118M. Segala,118 T. Sinthuprasith,118T. Speer,118R. Breedon,119G. Breto,119M. Calderon De La Barca Sanchez,119S. Chauhan,119 M. Chertok,119J. Conway,119R. Conway,119P. T. Cox,119R. Erbacher,119M. Gardner,119R. Houtz,119W. Ko,119 A. Kopecky,119R. Lander,119T. Miceli,119D. Pellett,119F. Ricci-Tam,119B. Rutherford,119M. Searle,119J. Smith,119

M. Squires,119M. Tripathi,119S. Wilbur,119R. Yohay,119V. Andreev,120D. Cline,120R. Cousins,120S. Erhan,120 P. Everaerts,120C. Farrell,120M. Felcini,120J. Hauser,120M. Ignatenko,120C. Jarvis,120G. Rakness,120P. Schlein,120,a

E. Takasugi,120P. Traczyk,120V. Valuev,120M. Weber,120J. Babb,121R. Clare,121J. Ellison,121J. W. Gary,121 G. Hanson,121P. Jandir,121H. Liu,121O. R. Long,121A. Luthra,121H. Nguyen,121S. Paramesvaran,121J. Sturdy,121 S. Sumowidagdo,121R. Wilken,121S. Wimpenny,121W. Andrews,122J. G. Branson,122G. B. Cerati,122S. Cittolin,122 D. Evans,122A. Holzner,122R. Kelley,122M. Lebourgeois,122J. Letts,122I. Macneill,122S. Padhi,122C. Palmer,122

G. Petrucciani,122M. Pieri,122M. Sani,122V. Sharma,122S. Simon,122E. Sudano,122M. Tadel,122Y. Tu,122 A. Vartak,122S. Wasserbaech,122,eeeF. Wu¨rthwein,122A. Yagil,122J. Yoo,122D. Barge,123C. Campagnari,123 M. D’Alfonso,123T. Danielson,123K. Flowers,123P. Geffert,123C. George,123F. Golf,123J. Incandela,123C. Justus,123 P. Kalavase,123D. Kovalskyi,123V. Krutelyov,123S. Lowette,123R. Magan˜a Villalba,123N. Mccoll,123V. Pavlunin,123 J. Ribnik,123J. Richman,123R. Rossin,123D. Stuart,123W. To,123C. West,123A. Apresyan,124A. Bornheim,124

J. Bunn,124Y. Chen,124E. Di Marco,124J. Duarte,124D. Kcira,124Y. Ma,124A. Mott,124H. B. Newman,124 C. Rogan,124M. Spiropulu,124V. Timciuc,124J. Veverka,124R. Wilkinson,124S. Xie,124R. Y. Zhu,124V. Azzolini,125

A. Calamba,125R. Carroll,125T. Ferguson,125Y. Iiyama,125D. W. Jang,125Y. F. Liu,125M. Paulini,125J. Russ,125

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H. Vogel,125I. Vorobiev,125J. P. Cumalat,126B. R. Drell,126W. T. Ford,126A. Gaz,126E. Luiggi Lopez,126 U. Nauenberg,126J. G. Smith,126K. Stenson,126K. A. Ulmer,126S. R. Wagner,126J. Alexander,127A. Chatterjee,127

N. Eggert,127L. K. Gibbons,127W. Hopkins,127A. Khukhunaishvili,127B. Kreis,127N. Mirman,127 G. Nicolas Kaufman,127J. R. Patterson,127A. Ryd,127E. Salvati,127W. Sun,127W. D. Teo,127J. Thom,127 J. Thompson,127J. Tucker,127Y. Weng,127L. Winstrom,127P. Wittich,127D. Winn,128S. Abdullin,129M. Albrow,129 J. Anderson,129G. Apollinari,129L. A. T. Bauerdick,129A. Beretvas,129J. Berryhill,129P. C. Bhat,129K. Burkett,129

J. N. Butler,129V. Chetluru,129H. W. K. Cheung,129F. Chlebana,129S. Cihangir,129V. D. Elvira,129I. Fisk,129 J. Freeman,129Y. Gao,129E. Gottschalk,129L. Gray,129D. Green,129O. Gutsche,129D. Hare,129R. M. Harris,129

J. Hirschauer,129B. Hooberman,129S. Jindariani,129M. Johnson,129U. Joshi,129K. Kaadze,129B. Klima,129 S. Kunori,129S. Kwan,129J. Linacre,129D. Lincoln,129R. Lipton,129J. Lykken,129K. Maeshima,129 J. M. Marraffino,129V. I. Martinez Outschoorn,129S. Maruyama,129D. Mason,129P. McBride,129K. Mishra,129

S. Mrenna,129Y. Musienko,129,fffC. Newman-Holmes,129V. O’Dell,129O. Prokofyev,129N. Ratnikova,129 E. Sexton-Kennedy,129S. Sharma,129W. J. Spalding,129L. Spiegel,129L. Taylor,129S. Tkaczyk,129N. V. Tran,129 L. Uplegger,129E. W. Vaandering,129R. Vidal,129J. Whitmore,129W. Wu,129F. Yang,129J. C. Yun,129D. Acosta,130

P. Avery,130D. Bourilkov,130M. Chen,130T. Cheng,130S. Das,130M. De Gruttola,130G. P. Di Giovanni,130 D. Dobur,130A. Drozdetskiy,130R. D. Field,130M. Fisher,130Y. Fu,130I. K. Furic,130J. Hugon,130B. Kim,130

J. Konigsberg,130A. Korytov,130A. Kropivnitskaya,130T. Kypreos,130J. F. Low,130K. Matchev,130 P. Milenovic,130,gggG. Mitselmakher,130L. Muniz,130R. Remington,130A. Rinkevicius,130N. Skhirtladze,130 M. Snowball,130J. Yelton,130M. Zakaria,130V. Gaultney,131S. Hewamanage,131S. Linn,131P. Markowitz,131 G. Martinez,131J. L. Rodriguez,131T. Adams,132A. Askew,132J. Bochenek,132J. Chen,132B. Diamond,132 S. V. Gleyzer,132J. Haas,132S. Hagopian,132V. Hagopian,132K. F. Johnson,132H. Prosper,132V. Veeraraghavan,132

M. Weinberg,132M. M. Baarmand,133B. Dorney,133M. Hohlmann,133H. Kalakhety,133F. Yumiceva,133 M. R. Adams,134L. Apanasevich,134V. E. Bazterra,134R. R. Betts,134I. Bucinskaite,134J. Callner,134 R. Cavanaugh,134O. Evdokimov,134L. Gauthier,134C. E. Gerber,134D. J. Hofman,134S. Khalatyan,134P. Kurt,134 F. Lacroix,134D. H. Moon,134C. O’Brien,134C. Silkworth,134D. Strom,134P. Turner,134N. Varelas,134U. Akgun,135

E. A. Albayrak,135,aaaB. Bilki,135,hhhW. Clarida,135K. Dilsiz,135F. Duru,135S. Griffiths,135J.-P. Merlo,135 H. Mermerkaya,135,iiiA. Mestvirishvili,135A. Moeller,135J. Nachtman,135C. R. Newsom,135H. Ogul,135Y. Onel,135

F. Ozok,135,aaaS. Sen,135P. Tan,135E. Tiras,135J. Wetzel,135T. Yetkin,135,jjjK. Yi,135B. A. Barnett,136 B. Blumenfeld,136S. Bolognesi,136G. Giurgiu,136A. V. Gritsan,136G. Hu,136P. Maksimovic,136C. Martin,136

M. Swartz,136A. Whitbeck,136P. Baringer,137A. Bean,137G. Benelli,137R. P. Kenny III,137M. Murray,137 D. Noonan,137S. Sanders,137R. Stringer,137J. S. Wood,137A. F. Barfuss,138I. Chakaberia,138A. Ivanov,138 S. Khalil,138M. Makouski,138Y. Maravin,138S. Shrestha,138I. Svintradze,138J. Gronberg,139D. Lange,139 F. Rebassoo,139D. Wright,139A. Baden,140B. Calvert,140S. C. Eno,140J. A. Gomez,140N. J. Hadley,140 R. G. Kellogg,140T. Kolberg,140Y. Lu,140M. Marionneau,140A. C. Mignerey,140K. Pedro,140A. Peterman,140 A. Skuja,140J. Temple,140M. B. Tonjes,140S. C. Tonwar,140A. Apyan,141G. Bauer,141W. Busza,141I. A. Cali,141

M. Chan,141L. Di Matteo,141V. Dutta,141G. Gomez Ceballos,141M. Goncharov,141D. Gulhan,141Y. Kim,141 M. Klute,141Y. S. Lai,141A. Levin,141P. D. Luckey,141T. Ma,141S. Nahn,141C. Paus,141D. Ralph,141C. Roland,141

G. Roland,141G. S. F. Stephans,141F. Sto¨ckli,141K. Sumorok,141D. Velicanu,141R. Wolf,141B. Wyslouch,141 M. Yang,141Y. Yilmaz,141A. S. Yoon,141M. Zanetti,141V. Zhukova,141B. Dahmes,142A. De Benedetti,142 G. Franzoni,142A. Gude,142J. Haupt,142S. C. Kao,142K. Klapoetke,142Y. Kubota,142J. Mans,142N. Pastika,142 R. Rusack,142M. Sasseville,142A. Singovsky,142N. Tambe,142J. Turkewitz,142J. G. Acosta,143L. M. Cremaldi,143

R. Kroeger,143S. Oliveros,143L. Perera,143R. Rahmat,143D. A. Sanders,143D. Summers,143E. Avdeeva,144 K. Bloom,144S. Bose,144D. R. Claes,144A. Dominguez,144M. Eads,144R. Gonzalez Suarez,144J. Keller,144 I. Kravchenko,144J. Lazo-Flores,144S. Malik,144F. Meier,144G. R. Snow,144J. Dolen,145A. Godshalk,145 I. Iashvili,145S. Jain,145A. Kharchilava,145A. Kumar,145S. Rappoccio,145Z. Wan,145G. Alverson,146E. Barberis,146 D. Baumgartel,146M. Chasco,146J. Haley,146A. Massironi,146D. Nash,146T. Orimoto,146D. Trocino,146D. Wood,146 J. Zhang,146A. Anastassov,147K. A. Hahn,147A. Kubik,147L. Lusito,147N. Mucia,147N. Odell,147B. Pollack,147

A. Pozdnyakov,147M. Schmitt,147S. Stoynev,147K. Sung,147M. Velasco,147S. Won,147D. Berry,148 A. Brinkerhoff,148K. M. Chan,148M. Hildreth,148C. Jessop,148D. J. Karmgard,148J. Kolb,148K. Lannon,148 W. Luo,148S. Lynch,148N. Marinelli,148D. M. Morse,148T. Pearson,148M. Planer,148R. Ruchti,148J. Slaunwhite,148

N. Valls,148M. Wayne,148M. Wolf,148L. Antonelli,149B. Bylsma,149L. S. Durkin,149C. Hill,149R. Hughes,149

(13)

K. Kotov,149T. Y. Ling,149D. Puigh,149M. Rodenburg,149G. Smith,149C. Vuosalo,149B. L. Winer,149H. Wolfe,149 E. Berry,150P. Elmer,150V. Halyo,150P. Hebda,150J. Hegeman,150A. Hunt,150P. Jindal,150S. A. Koay,150P. Lujan,150 D. Marlow,150T. Medvedeva,150M. Mooney,150J. Olsen,150P. Piroue´,150X. Quan,150A. Raval,150H. Saka,150

D. Stickland,150C. Tully,150J. S. Werner,150S. C. Zenz,150A. Zuranski,150E. Brownson,151A. Lopez,151 H. Mendez,151J. E. Ramirez Vargas,151E. Alagoz,152D. Benedetti,152G. Bolla,152D. Bortoletto,152M. De Mattia,152 A. Everett,152Z. Hu,152M. Jones,152K. Jung,152O. Koybasi,152M. Kress,152N. Leonardo,152D. Lopes Pegna,152 V. Maroussov,152P. Merkel,152D. H. Miller,152N. Neumeister,152I. Shipsey,152D. Silvers,152A. Svyatkovskiy,152 M. Vidal Marono,152F. Wang,152W. Xie,152L. Xu,152H. D. Yoo,152J. Zablocki,152Y. Zheng,152S. Guragain,153

N. Parashar,153A. Adair,154B. Akgun,154K. M. Ecklund,154F. J. M. Geurts,154W. Li,154B. P. Padley,154 R. Redjimi,154J. Roberts,154J. Zabel,154B. Betchart,155A. Bodek,155R. Covarelli,155P. de Barbaro,155 R. Demina,155Y. Eshaq,155T. Ferbel,155A. Garcia-Bellido,155P. Goldenzweig,155J. Han,155A. Harel,155 D. C. Miner,155G. Petrillo,155D. Vishnevskiy,155M. Zielinski,155A. Bhatti,156R. Ciesielski,156L. Demortier,156

K. Goulianos,156G. Lungu,156S. Malik,156C. Mesropian,156S. Arora,157A. Barker,157J. P. Chou,157 C. Contreras-Campana,157E. Contreras-Campana,157D. Duggan,157D. Ferencek,157Y. Gershtein,157R. Gray,157 E. Halkiadakis,157D. Hidas,157A. Lath,157S. Panwalkar,157M. Park,157R. Patel,157V. Rekovic,157J. Robles,157 S. Salur,157S. Schnetzer,157C. Seitz,157S. Somalwar,157R. Stone,157S. Thomas,157P. Thomassen,157M. Walker,157

G. Cerizza,158M. Hollingsworth,158K. Rose,158S. Spanier,158Z. C. Yang,158A. York,158O. Bouhali,159,kkk R. Eusebi,159W. Flanagan,159J. Gilmore,159T. Kamon,159,lllV. Khotilovich,159R. Montalvo,159I. Osipenkov,159 Y. Pakhotin,159A. Perloff,159J. Roe,159A. Safonov,159T. Sakuma,159I. Suarez,159A. Tatarinov,159D. Toback,159 N. Akchurin,160C. Cowden,160J. Damgov,160C. Dragoiu,160P. R. Dudero,160C. Jeong,160K. Kovitanggoon,160

S. W. Lee,160T. Libeiro,160I. Volobouev,160E. Appelt,161A. G. Delannoy,161S. Greene,161A. Gurrola,161 W. Johns,161C. Maguire,161Y. Mao,161A. Melo,161M. Sharma,161P. Sheldon,161B. Snook,161S. Tuo,161 J. Velkovska,161M. W. Arenton,162S. Boutle,162B. Cox,162B. Francis,162J. Goodell,162R. Hirosky,162

A. Ledovskoy,162C. Lin,162C. Neu,162J. Wood,162S. Gollapinni,163R. Harr,163P. E. Karchin,163 C. Kottachchi Kankanamge Don,163P. Lamichhane,163A. Sakharov,163D. A. Belknap,164L. Borrello,164 D. Carlsmith,164M. Cepeda,164S. Dasu,164E. Friis,164M. Grothe,164R. Hall-Wilton,164M. Herndon,164A. Herve´,164

P. Klabbers,164J. Klukas,164A. Lanaro,164R. Loveless,164A. Mohapatra,164M. U. Mozer,164I. Ojalvo,164 G. A. Pierro,164G. Polese,164I. Ross,164A. Savin,164W. H. Smith,164and J. Swanson164

(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 6Universite´ 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

12aUniversidade Estadual Paulista, Sa˜o Paulo, Brazil 12b

Universidade Federal do ABC, Sa˜o Paulo, Brazil

13Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria 14University of Sofia, Sofia, Bulgaria

15Institute of High Energy Physics, Beijing, China

16State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China 17Universidad de Los Andes, Bogota, Colombia

18Technical University of Split, Split, Croatia 19University of Split, Split, Croatia 20Institute Rudjer Boskovic, Zagreb, Croatia

21

University of Cyprus, Nicosia, Cyprus

22Charles University, Prague, Czech Republic

(14)

23Academy of Scientific Research and Technology of the Arab Republic of Egypt,

Egyptian Network of High Energy Physics, Cairo, Egypt

24National Institute of Chemical Physics and Biophysics, Tallinn, Estonia 25Department of Physics, University of Helsinki, Helsinki, Finland

26Helsinki Institute of Physics, Helsinki, Finland 27Lappeenranta University of Technology, Lappeenranta, Finland

28DSM/IRFU, CEA/Saclay, Gif-sur-Yvette, France

29Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France 30

Institut Pluridisciplinaire Hubert Curien, Universite´ de Strasbourg, Universite´ de Haute Alsace Mulhouse, CNRS/IN2P3, Strasbourg, France

31Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique des Particules, CNRS/IN2P3, Villeurbanne, France 32Universite´ de Lyon, Universite´ Claude Bernard Lyon 1, CNRS-IN2P3, Institut de Physique Nucle´aire de Lyon, Villeurbanne, France

33Institute of High Energy Physics and Informatization, Tbilisi State University, Tbilisi, Georgia 34RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany

35RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany 36RWTH Aachen University, III. Physikalisches Institut B, Aachen, Germany

37Deutsches Elektronen-Synchrotron, Hamburg, Germany 38University of Hamburg, Hamburg, Germany 39Institut fu¨r Experimentelle Kernphysik, Karlsruhe, Germany

40Institute of Nuclear and Particle Physics (INPP), NCSR Demokritos, Aghia Paraskevi, Greece 41University of Athens, Athens, Greece

42University of Ioa´nnina, Ioa´nnina, Greece

43KFKI Research Institute for Particle and Nuclear Physics, Budapest, Hungary 44Institute of Nuclear Research ATOMKI, Debrecen, Hungary

45

University of Debrecen, Debrecen, Hungary

46National Institute of Science Education and Research, Bhubaneswar, India 47Panjab University, Chandigarh, India

48University of Delhi, Delhi, India 49Saha Institute of Nuclear Physics, Kolkata, India

50Bhabha Atomic Research Centre, Mumbai, India 51Tata Institute of Fundamental Research—EHEP, Mumbai, India 52Tata Institute of Fundamental Research—HECR, Mumbai, India 53Institute for Research in Fundamental Sciences (IPM), Tehran, Iran

54University College Dublin, Dublin, Ireland 55aINFN Sezione di Bari, Bari, Italy

55bUniversita` di Bari, Bari, Italy 55cPolitecnico di Bari, Bari, Italy 56aINFN Sezione di Bologna, Bologna, Italy

56bUniversita` di Bologna, Bologna, Italy 57aINFN Sezione di Catania, Catania, Italy

57bUniversita` di Catania, Catania, Italy 58aINFN Sezione di Firenze, Firenze, Italy

58bUniversita` di Firenze, Firenze, Italy

59INFN Laboratori Nazionali di Frascati, Frascati, Italy 60aINFN Sezione di Genova, Genova, Italy

60bUniversita` di Genova, Genova, Italy 61aINFN Sezione di Milano-Bicocca, Milano, Italy

61b

Universita` di Milano-Bicocca, Milano, Italy

62aINFN Sezione di Napoli, Napoli, Italy 62bUniversita` di Napoli ‘Federico II’, Napoli, Italy 62cUniversita` della Basilicata (Potenza), Napoli, Italy

62dUniversita` G. Marconi (Roma), Napoli, Italy 63aINFN Sezione di Padova, Padova, Italy

63bUniversita` di Padova, Padova, Italy 63cUniversita` di Trento (Trento), Padova, Italy

64aINFN Sezione di Pavia, Pavia, Italy 64b

Universita` di Pavia, Pavia, Italy

65aINFN Sezione di Perugia, Perugia, Italy 65bUniversita` di Perugia, Perugia, Italy

66aINFN Sezione di Pisa, Pisa, Italy 66bUniversita` di Pisa, Pisa, Italy

(15)

66cScuola Normale Superiore di Pisa, Pisa, Italy 67aINFN Sezione di Roma, Roma, Italy

67bUniversita` di Roma, Roma, Italy 68aINFN Sezione di Torino, Torino, Italy

68bUniversita` di Torino, Torino, Italy

68cUniversita` del Piemonte Orientale (Novara), Torino, Italy 69aINFN Sezione di Trieste, Trieste, Italy

69bUniversita` di Trieste, Trieste, Italy 70

Kangwon National University, Chunchon, Korea

71Kyungpook National University, Daegu, Korea

72Chonnam National University, Institute for Universe and Elementary Particles, Kwangju, Korea 73Korea University, Seoul, Korea

74University of Seoul, Seoul, Korea 75Sungkyunkwan University, Suwon, Korea

76Vilnius University, Vilnius, Lithuania

77Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico 78Universidad Iberoamericana, Mexico City, Mexico

79Benemerita Universidad Autonoma de Puebla, Puebla, Mexico 80Universidad Auto´noma de San Luis Potosı´, San Luis Potosı´, Mexico

81University of Auckland, Auckland, New Zealand 82University of Canterbury, Christchurch, New Zealand

83National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan 84National Centre for Nuclear Research, Swierk, Poland

85Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland 86

Laborato´rio de Instrumentac¸a˜o e Fı´sica Experimental de Partı´culas, Lisboa, Portugal

87Joint Institute for Nuclear Research, Dubna, Russia

88Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), Russia 89Institute for Nuclear Research, Moscow, Russia

90Institute for Theoretical and Experimental Physics, Moscow, Russia 91P. N. Lebedev Physical Institute, Moscow, Russia

92Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia 93State Research Center of Russian Federation, Institute for High Energy Physics, Protvino, Russia 94University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia

95Centro de Investigaciones Energe´ticas Medioambientales y Tecnolo´gicas (CIEMAT), Madrid, Spain 96Universidad Auto´noma de Madrid, Madrid, Spain

97Universidad de Oviedo, Oviedo, Spain

98Instituto de Fı´sica de Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, Spain 99CERN, European Organization for Nuclear Research, Geneva, Switzerland

100Paul Scherrer Institut, Villigen, Switzerland

101Institute for Particle Physics, ETH Zurich, Zurich, Switzerland 102Universita¨t Zu¨rich, Zurich, Switzerland

103National Central University, Chung-Li, Taiwan 104National Taiwan University (NTU), Taipei, Taiwan

105Chulalongkorn University, Bangkok, Thailand 106Cukurova University, Adana, Turkey

107Middle East Technical University, Physics Department, Ankara, Turkey 108Bogazici University, Istanbul, Turkey

109

Istanbul Technical University, Istanbul, Turkey

110National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, Ukraine 111University of Bristol, Bristol, United Kingdom

112Rutherford Appleton Laboratory, Didcot, United Kingdom 113Imperial College, London, United Kingdom 114Brunel University, Uxbridge, United Kingdom

115Baylor University, Waco, Texas, USA

116The University of Alabama, Tuscaloosa, Alabama, USA 117Boston University, Boston, Massachusetts, USA 118

Brown University, Providence, Rhode Island, USA

119University of California, Davis, Davis, California, USA 120University of California, Los Angeles, Los Angeles, California, USA

121University of California, Riverside, Riverside, California, USA 122University of California, San Diego, La Jolla, California, USA

Figura

TABLE I. Summary of the relative experimental uncertainties in the yields for the bins of largest jyj
FIG. 1 (color online). Distributions in absolute values of rapidities for (a) the Z boson, (b) the jet, (c) their sums, and (d) their differences, normalized to unity
FIG. 2 (color online). Distributions in absolute values of rapidities for (a) the photon, (b) the jet, (c) their sums, and (d) their differences, normalized to unity

Riferimenti

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