Observation of spin correlation in $t \bar{t}$ events from pp collisions at sqrt(s) = 7 TeV using the ATLAS detector

arXiv:1203.4081v3 [hep-ex] 24 Jan 2013

CERN-PH-EP-2012-074

Submitted to: Physical Review Letters

Observation of spin correlation in

t¯

t

events from

pp

collisions

at

√s = 7 TeV

using the ATLAS detector

The ATLAS Collaboration

Abstract

A measurement of spin correlation in

t¯

t

production is reported using data collected with the ATLAS

detector at the LHC, corresponding to an integrated luminosity of

2.1

fb

. Candidate events are

se-lected in the dilepton topology with large missing transverse energy and at least two jets. The

differ-ence in azimuthal angle between the two charged leptons in the laboratory frame is used to extract

the correlation between the top and antitop quark spins. In the helicity basis the measured degree of

correlation corresponds to

A

= 0.40

−0.08

, in agreement with the next-to-leading-order Standard

at

√s = 7 TeV using the ATLAS detector

(Dated: January 25, 2013)

A measurement of spin correlation in t¯t production is reported using data collected with the

ATLAS detector at the LHC, corresponding to an integrated luminosity of 2.1 fb−1_{. Candidate}

events are selected in the dilepton topology with large missing transverse energy and at least two jets. The difference in azimuthal angle between the two charged leptons in the laboratory frame is used to extract the correlation between the top and antitop quark spins. In the helicity basis the

measured degree of correlation corresponds to Ahelicity= 0.40+0.09_−0.08, in agreement with the

next-to-leading-order Standard Model prediction. The hypothesis of zero spin correlation is excluded at 5.1 standard deviations.

PACS numbers: 14.65.Ha, 12.38.Qk, 13.85.Qk

The top quark was discovered in 1995 [1, 2] at the Tevatron proton-antiproton collider. The lifetime of the top quark is at least an order of magnitude shorter than the timescale for strong interactions, implying that the top quark decays before hadronization [3–7]. Therefore the spin of the top quark at production is transferred to its decay products and can be measured directly via their angular distributions [4]. While the polarization of t and ¯t quarks in a hadronically produced t¯t sample is predicted to be very small, their spins are predicted to be correlated [8–10]. In this Letter the hypothesis that the correlation of the spin of top and antitop quarks in t¯t events is as expected in the Standard Model (SM), as opposed to the hypothesis that they are uncorrelated, is tested. This tests the precise predictions of t¯t pair production and of top quark decay, which is expected to occur before its spin is flipped by the strong interac-tion [9–13]. Many scenarios of new physics beyond the SM predict different spin correlations whilst keeping the t¯t production cross section within experimental and theo-retical bounds [14–18]. For example, the spin correlation measured in this Letter may differ from the SM if the t¯t pairs were produced via the exchange of a virtual heavy scalar Higgs boson [19] or if the top quark decayed into a scalar charged Higgs boson and a b-quark (t → H+_{b) [20].} At the LHC t¯t production occurs mostly through the gg → t¯tchannel. At low t¯tinvariant mass it is dominated by the fusion of like-helicity gluon pairs which produce top quarks in the left-left or right-right helicity configu-rations [13]. When these decay via t¯t → W+_W−_{b¯b →} l+_νl−_{νb¯b they produce charged leptons which possess¯} correlations in azimuthal angle, ∆φ [21], in the labora-tory frame [13]. In contrast, at the Tevatron production via q ¯q annihilation dominates. The different production mechanisms and center-of-mass energies make a measure-ment of the spin correlation at both colliders complemen-tary [22]. Both the CDF and DØ Collaborations have performed measurements of the spin correlation [23–25], with a recent analysis by the DØ Collaboration reporting evidence for the presence of spin correlation in t¯t events with a significance of 3.1 standard deviations [26].

The azimuthal angle between charged leptons is well

measured by the ATLAS detector and does not require reconstruction of the top quarks. Figure 1 shows the dis-tribution of charged lepton ∆φ for generated events at parton level for√s = 7 TeV, using MC@NLO [27–29] with the CTEQ6.6 parton distribution function (PDF) [30] and a top quark mass of 172.5 GeV. It compares the SM prediction (solid line) to a scenario with no spin correla-tion between top and antitop quarks (dashed line).

φ ∆ 0 0.5 1 1.5 2 2.5 3 ) φ∆ /d( σ ) d σ (1/ 0 0.1 0.2 0.3 0.4 0.5 0.6 (SM) t t (uncorrelated) t t ATLAS Simulation

FIG. 1. Normalized reconstructed charged lepton ∆φ

distri-bution for generated events at parton level for√s = 7 TeV

using MC@NLO. The two histograms show the SM and uncor-related spin scenarios.

The degree of correlation, A, is defined as the fractional difference between the number of events where the top and antitop quark spin orientations are aligned and those where the top quark spins have opposite alignment,

A = N (↑↑) + N(↓↓) − N(↑↓) − N(↓↑)

N (↑↑) + N(↓↓) + N(↑↓) + N(↓↑). (1) The arrows denote the spins of the top and antitop quarks with respect to a chosen quantization axis. This analysis uses a fit to templates constructed from simulated event samples to determine the amount of spin correlation from

the ∆φ distribution. The fit result is converted into a value of A in two bases: the helicity basis, using the di-rection of flight of the top quark in the center-of-mass frame of the t¯t system [31, 32], and the maximal basis which is optimized for t¯t production from gg fusion, as described in Ref. [12]. In the helicity basis the SM cor-relation coefficient is calculated to be ASM

helicity= 0.31 [8], and in the maximal basis ASM

maximal= 0.44, evaluated at matrix-element level using MC@NLO. Theoretical uncer-tainties due to the variation of factorization and renor-malization scales and due to PDFs are of the order of 1% including next-to-leading-order (NLO) QCD corrections in t¯t production and top quark decay [22].

The ATLAS detector [33] at the LHC covers nearly the entire solid angle around the collision point. It consists of an inner tracking detector (ID) covering |η| < 2.5 and comprising a silicon pixel detector, a silicon microstrip detector and a transition radiation tracker. The ID is surrounded by a thin superconducting solenoid provid-ing a 2 T magnetic field, followed by a liquid argon electromagnetic sampling calorimeter (LAr) with high granularity. An iron-scintillator tile calorimeter provides hadronic energy measurements in the central rapidity region (|η| < 1.7). The end-cap and forward regions are instrumented with LAr calorimeters for both electro-magnetic (EM) and hadronic energy measurements up to |η| < 4.9. The calorimeter system is surrounded by a muon spectrometer (MS) with high-precision tracking chambers covering |η| < 2.7 and separate trigger cham-bers. The magnetic field is provided by a barrel and two end-cap superconducting toroid magnets. A three-level trigger system is used to select events with high-pT leptons for this analysis. The first-level trigger is imple-mented in hardware and uses a subset of the detector information to reduce the trigger rate to 75 kHz. This is followed by two software-based trigger levels that to-gether reduce the event rate to 200 − 400 Hz.

This analysis uses collision data with a center-of-mass energy of√s = 7 TeV recorded between March 22 and August 22, 2011, corresponding to an integrated lumi-nosity of 2.1 fb−1_{. The luminosity is given with an} un-certainty of 3.7% [34, 35].

Monte Carlo (MC) simulation samples are used to eval-uate the contributions, and shapes of distributions of kinematic variables, for signal t¯t events and background processes not evaluated from complementary data sam-ples. All MC samples are processed with the GEANT4 [36] simulation of the ATLAS detector [37] and are passed through the same analysis chain as data. The simula-tion includes multiple pp interacsimula-tions per bunch crossing (pile-up). Events are weighted such that the distribution of the average number of interactions per bunch cross-ing matches that observed in data. The mean number of pile-up interactions varies between 5.7 and 7.1 for the different data-taking periods.

Samples with SM spin correlation and without

spin correlation are generated using MC@NLO with the CTEQ6.6 PDF set and a top quark mass of 172.5 GeV. In both cases the events are hadronized using the HERWIG shower model [38, 39]. Within the statistical uncertainty of the MC generation the yields of the SM t¯t and uncor-related t¯t samples are the same. The background MC samples are described in Ref. [40].

Candidate events are selected in the dilepton topol-ogy. Channels with τ leptons are not explicitly consid-ered, but reconstructed leptons can arise from leptonic τ decays and are included in the signal MC samples. The full object and event selection is discussed in Ref. [40]; therefore only a brief overview is given here. The analy-sis requires events selected online by an inclusive single-lepton trigger (e or µ). The detailed trigger requirements vary throughout data-taking, but the pT threshold en-sures that the triggered lepton candidate is in the ef-ficiency plateau. Electron candidates are reconstructed using energy deposits in the EM calorimeter associated to reconstructed tracks of charged particles in the ID. Muon candidate reconstruction makes use of tracking in the MS and ID. Jets are reconstructed with the anti-kt algorithm [41] with a radius parameter R = 0.4, starting from energy clusters of adjacent calorimeter cells. The symbol Emiss

T is used to denote the magnitude of the miss-ing transverse momentum [42]. The followmiss-ing kinematic requirements are made:

• Electron candidates are required to have pT > 25 GeV and |η| < 2.47, excluding electrons from the transition region between the barrel and end-cap calorimeters defined by 1.37 < |η| < 1.52. Muon candidates are required to have pT> 20 GeV and |η| < 2.5. Events must have exactly two oppositely-charged lepton candidates (e+_e−_{, µ}+_µ−_{, e}±_µ∓_). • Events must have at least two jets with pT >

25 GeV and |η| < 2.5.

• Events in the e+_e−_{and µ}+_µ−_{channels are required} to have mℓℓ> 15 GeV to ensure compatibility with the MC samples and remove contributions from Υ and J/ψ production.

• Events in the e+_e−_{and µ}+_µ−_{channels must satisfy} Emiss

T > 60 GeV to suppress backgrounds from Z/γ∗_{+jets and W +jets events. In addition, m}

ℓℓ must differ by at least 10 GeV from the Z-boson mass (mZ = 91 GeV) to further suppress the Z/γ∗_{+jets background.}

• For the e±_µ∓_{channel, no E}miss

T or mℓℓcuts are ap-plied. In this case, the remaining background from Z/γ∗_{(→ ττ)+jets production is further suppressed} by requiring that the scalar sum of the pT of all selected jets and leptons is greater than 130 GeV.

The event selection rejects Z/γ∗_{+jets events with low} invariant mass and those with invariant mass near the Z-boson mass. However Z/γ∗_{+jets events with an e}+_e− or µ+_µ− _{invariant mass outside of these regions can} en-ter the signal sample when there is large Emiss

T , typi-cally from mismeasurement. These events are difficult to properly model in simulations due to uncertainties on the non-Gaussian tails of the Emiss

T distribution, on the cross section for Z-boson production with multiple jets, and on the lepton energy resolution. The Z/γ∗_{+jets background} in dielectron and dimuon events is evaluated using a data-driven (DD) technique in which the MC simulation yield of Z/γ∗_{+jets events is normalized to the data using a} control region defined by a dilepton invariant mass within 10 GeV of the Z-boson mass [40].

The backgrounds from events with misidentified (fake) leptons, primarily from W +jets events, are evaluated from data using a matrix method [43]. The matrix method makes use of the efficiency of real lepton identi-fication and rate of lepton misidentiidenti-fication measured in several control regions, which are chosen to be enhanced in different sources of fake leptons [40]. Contributions from real leptons due to W +jets events in the fake lep-ton control region are subtracted using MC simulation. Comparisons of data and MC simulation in control re-gions are used to tune the rates to the expected signal region composition. The fake lepton yield is then esti-mated by weighting each event in a sample containing one or two loosely-identified leptons.

The contributions from other electroweak background processes with two real leptons, such as single top, Z → τ τ , W W , ZZ and W Z production are determined from MC simulations normalized to the theoretical predic-tions. The expected numbers of signal and background events are compared to data in Table I. The number of observed events in each channel is: 477 for the e+_e− channel, 906 for the µ+_µ−_{channel and 2930 for the e}±_µ∓ channel, which dominates the total yield due to the looser selection criteria.

TABLE I. Observed dilepton yield in data and the expected signal and background composition from MC and DD sam-ples. Systematic uncertainties are included.

Z/γ∗_{(→ e}+_e−_/µ+_µ−_{)+jets (MC+DD) 64}+11 −16 Z/γ∗_{(→ τ τ )+jets (MC) 175 ± 29} Fake leptons (DD) 160+140 −70 Single top (MC) 197 ± 21 Diboson (MC) 148 ± 20 Total (non-t¯t) 740+150 −80 t¯t (MC) 3530+280 −340 Total expected 4270+320 −350 Observed 4313

A binned log-likelihood fit is used to extract the spin correlation from the ∆φ distribution in data. The fit in-cludes a linear superposition of the distribution from SM t¯t MC simulation with coefficient fSM_{, and from the} un-correlated t¯t MC simulation with coefficient (1 − fSM_). The e+_e−_{, µ}+_µ− _{and e}±_µ∓ _{channels are fitted} simulta-neously with a common value of fSM_{, a t¯t normalization} that is allowed to vary (per channel) and a fixed back-ground normalization. The fitted t¯t normalizations are in agreement with the theoretical prediction of the produc-tion cross secproduc-tion [44]. Negative values of fSM_correspond to an anti-correlation of the top and antitop quark spins. A value of fSM _{= 0 implies that the spins are} uncorre-lated and values of fSM _{> 1 indicate a larger strength of} the t¯t spin correlation than predicted by the SM. The ex-traction of fSM _{using the fitting procedure has been} ver-ified over a wide range of possible values, −1 ≤ fSM_{≤ 2,} using MC simulation pseudo-experiments with full detec-tor simulation.

Figure 2 shows the reconstructed ∆φ distribution for the sum of the three dilepton channels in data. SM and uncorrelated t¯t MC samples are overlaid along with the expected backgrounds. φ ∆ 0 0.5 1 1.5 2 2.5 3 Events 0 100 200 300 400 500 600 700 800 900 _data (SM) t t (uncorrelated) t t single top *+jets γ Z/ diboson fake leptons ATLAS -1 Ldt = 2.1 fb

∫

FIG. 2. Reconstructed charged lepton ∆φ distribution for

the sum of the three dilepton channels. The integrated

num-ber of events for both the SM and the uncorrelated t¯t samples

is fixed to the value from the fit. MC background samples are normalized using their predicted cross sections and the DD

method in the case of Z/γ∗_{+jets. The fake lepton background}

is evaluated from data.

Systematic uncertainties are evaluated by applying the fit procedure to pseudo-experiments created from MC samples modified to reflect the systematic variations. The fit of fSM_{is repeated to determine the effect of each} systematic uncertainty using the nominal templates. The difference between the means of Gaussian fits to the re-sults from many pseudo-experiments using nominal and modified pseudo-data is taken as the systematic

uncer-tainty on fSM_.

The effect of the luminosity uncertainty is evaluated by scaling the number of signal and background events by the luminosity uncertainty, for backgrounds evaluated from MC simulation. Due to the finite size of the MC samples, the signal and background templates have sta-tistical uncertainties. Each template bin is varied within its uncertainty, then fSM _{is re-evaluated. The resulting} distribution for fSM_{is fitted with a Gaussian. The width} is taken as the MC simulation statistical uncertainty.

The mis-modeling of the muon (electron) trigger, re-construction and selection efficiencies in the simulation is corrected using scale factors derived from measurements of the efficiency in data. Z → µ+_µ−_{(Z → e}+_e−_{) decays} are used to obtain scale factors as a function of the kine-matic variables of the leptons. Systekine-matic uncertainties on these scale factors are evaluated by varying the selec-tion of events used in the efficiency measurements and by checking the stability of the measurements over the course of the data-taking period. The modeling of the lepton momentum scale and resolution is studied using the reconstructed dilepton invariant mass distributions of Z/γ∗ _{candidate events and the simulation is adjusted} accordingly.

The jet energy scale, jet energy resolution and recon-struction efficiency affect the acceptance. The jet energy scale and its uncertainty are derived by combining in-formation from test-beam data, LHC collision data and simulation [45]. For jets within the acceptance, the jet energy scale varies in the range 4 − 10% as a function of jet pTand η, including an additional uncertainty due to multiple pp interactions. The energy resolution for jets is measured in dijet events and agrees with predictions from simulation within 10% for jets with pT > 30 GeV. The jet reconstruction efficiency is evaluated using minimum bias and dijet events and depends on the pT of the jet. Its systematic uncertainty is in the range 1−3% based on the comparison of data and MC simulation. The uncer-tainties from the energy scale and resolution corrections for leptons and jets are propagated into the calculation of Emiss

T .

The uncertainty on the kinematic properties of the t¯t signal events gives rise to systematic uncertainties on the shape of the ∆φ distribution and signal acceptance. This is evaluated by considering the choice of generator, the parton shower and fragmentation model, the mod-eling of initial and final state radiation (ISR/FSR), the PDF and top quark mass. The generator uncertainty is evaluated by comparing the MC@NLO predictions with those of POWHEG [46–48] interfaced to HERWIG. To esti-mate the uncertainty due to the parton shower modeling and fragmentation, the difference between POWHEG inter-faced to HERWIG (cluster fragmentation) and PYTHIA [49] (string fragmentation) is taken. The uncertainty due to ISR/FSR is evaluated using the ACERMC generator [50] interfaced to the PYTHIA shower model, by varying the

parameters controlling ISR and FSR in a range consis-tent with those used in the Perugia Hard/Soft tune vari-ations [51]. The average of the absolute values of the upward and downward variations is taken as the system-atic uncertainty. The impact of the choice of PDF in simulation was studied by reweighting the MC samples to three PDF sets (CTEQ6.6, MSTW2008NLO [52] and NNPDF20 [53]) and taking the largest of either the vari-ation interval (from the error sets) or difference between the central values of any two PDF sets [32]. The system-atic uncertainty associated with the top quark mass is assessed using MC@NLO samples generated assuming dif-ferent top quark masses in the range 167.5 to 177.5 GeV in increments of 2.5 GeV. The values of fSM _{are fitted} as a linear function of the top quark mass and a conser-vative systematic uncertainty is obtained by evaluating this function at 172.5 ± 2.5 GeV.

Overall normalization uncertainties on the back-grounds from single top quark and diboson production are taken to be 10% [54, 55] and 5% [56] respectively. The resulting uncertainty on fSM _{is found to be} negligi-ble. The systematic uncertainties from the background evaluations derived from the data include the statistical uncertainties in these methods as well as the systematic uncertainties arising from lepton and jet identification and reconstruction, and the MC simulation estimates used. An uncertainty on the DD Z/γ∗_{+jets estimation is} evaluated by varying the Emiss

T cut in the control region by ±5 GeV and is found to be negligible. A mis-modeling of the Z-boson pTis observed in the Z-boson dominated control region. The Z-boson pTdistribution is weighted to achieve agreement with data and the difference be-tween the unweighted and weighted MC simulation is taken as an additional, but negligible, modeling uncer-tainty on fSM_{. For the DD fake lepton background the} systematic uncertainty affects the shape of the ∆φ distri-bution. Systematic uncertainties are derived by adjust-ing the signal region composition based on uncertainties estimated from MC simulation, and by comparing data and MC samples. The different sources of fake leptons have different shapes and the change in relative flavor composition of the sample gives an estimate of the shape uncertainty.

Due to a hardware failure a small rectangular region of the LAr calorimeter could not be read out in a sub-set of the data (0.87 fb−1_{). This affects the electron, jet} and Emiss

T reconstruction. Electrons within the affected region are rejected, as are events in which a jet with pT > 20 GeV is in the affected region. The MC simu-lation is divided into subsamples based on the fraction of the total luminosity affected and treated in the same way as data. A systematic uncertainty is evaluated by comparing MC simulation with and without the jet and electron rejection.

The effect of the systematic uncertainties in terms of ∆fSM _{are listed in Table II. The total systematic}

tainty is calculated by combining all systematic uncer-tainties in quadrature.

TABLE II. Summary of the effect of statistical and systematic

uncertainties on the measured value of fSM_{for the combined}

fit.

Uncertainty source ∆fSM

Data statistics _±0.14

MC simulation template statistics _±0.09

Luminosity _±0.01

Lepton _±0.01

Jet energy scale, resolution and efficiency _±0.12

NLO generator _±0.08

Parton shower and fragmentation _±0.08

ISR/FSR _±0.07

PDF uncertainty _±0.07

Top quark mass _±0.01

Fake leptons +0.16/−0.07

Calorimeter readout _±0.01

All systematics +0.27/−0.22

Statistical + Systematic +0.30/−0.26

The measured value of fSM _{for the combined fit is} found to be 1.30 ± 0.14 (stat) +0.27−0.22 (syst). This can be used to obtain a value for Ameasured

basis by applying it as a multiplicative factor to the NLO QCD prediction of Abasis using Ameasuredbasis = ASMbasis·fSM, where the subscript ‘basis’ indicates a chosen spin basis [11]. For the helicity basis this results in Ahelicity = 0.40 ± 0.04 (stat) +0.08−0.07 (syst), and for the maximal basis Amaximal= 0.57 ± 0.06 (stat)+0.12_−0.10(syst), where the SM predictions are 0.31 and 0.44 respectively. MC simulation pseudo-experiments in-cluding systematic uncertainties are used to calculate the probability that a value of fSM_{or larger is measured} us-ing the assumption of fSM _{= 0. For the observed limit} the value of fSM_{measured in data is used and for the} ex-pected limit a value of fSM _{= 1 is used. The hypothesis} of zero t¯t spin correlation is excluded with a significance of 5.1 standard deviations. The expected significance is 4.2 standard deviations.

In conclusion, the first measurement of t¯t spin corre-lation at the LHC has been presented using 2.1 fb−1 _of ATLAS data in the dilepton decay topology. A template fit is performed to the ∆φ distribution and the measured value of fSM_{= 1.30 ± 0.14 (stat)}+0.27

−0.22(syst) is consistent with the SM prediction. The data are inconsistent with the hypothesis of zero spin correlation with a significance of 5.1 standard deviations.

ACKNOWLEDGEMENTS

We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina;

YerPhI, Armenia; ARC, Australia; BMWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONI-CYT, Chile; CAS, MOST and NSFC, China; COLCIEN-CIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Founda-tion, Denmark; EPLANET and ERC, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNAS, Geor-gia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT, Greece; ISF, MINERVA, GIF, DIP and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; RCN, Norway; MNiSW, Poland; GRICES and FCT, Portugal; MERYS (MECTS), Romania; MES of Rus-sia and ROSATOM, RusRus-sian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MVZT, Slovenia; DST/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Can-tons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Lever-hulme Trust, United Kingdom; DOE and NSF, United States of America.

The crucial computing support from all WLCG part-ners is acknowledged gratefully, in particular from CERN and the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Tai-wan), RAL (UK) and BNL (USA) and in the Tier-2 fa-cilities worldwide.

[1] D0 Collaboration, S. Abachi, et al., Phys. Rev. Lett. 74, 2422 (1995).

[2] CDF Collaboration, F. Abe, et al., Phys. Rev. Lett. 74, 2626 (1995).

[3] I. I. Y. Bigi, Y. L. Dokshitzer, V. A. Khoze, J. H. Kuhn, and P. M. Zerwas, Phys. Lett. B 181, 157 (1986). [4] M. Beneke et al., arXiv:hep-ph/0003033.

[5] W. Bernreuther, J. Phys. G 35, 083001 (2008).

[6] CDF Collaboration, T. Aaltonen, et al., Phys. Rev. Lett.

105_{, 232003 (2010).}

[7] D0 Collaboration, V. M. Abazov, et al., Phys. Rev. Lett.

106, 022001 (2011).

[8] W. Bernreuther and Z. G. Si, Nucl. Phys. B 837, 90 (2010), and private communication.

[9] G. Mahlon and S. Parke, Phys. Rev. D 53, 4886 (1996). [10] T. Stelzer and S. Willenbrock, Phys. Lett. B 374, 169

(1996).

[11] W. Bernreuther, A. Brandenburg, Z. G. Si, and P. Uwer, Phys. Rev. Lett. 87, 242002 (2001).

[12] P. Uwer, Phys. Lett. B 609, 271 (2005).

[13] G. Mahlon and S. Parke, Phys. Rev. D 81, 074024 (2010). [14] R. Frederix and F. Maltoni, JHEP 01, 047 (2009). [15] M. Arai, N. Okada, and K. Smolek, Phys. Rev. D 79,

074019 (2009).

D 45, 124 (1992).

[17] K. Cheung, Phys. Rev. D 55, 4430 (1997).

[18] J.-Y. Liu, Z.-G. Si, and C.-X. Yue, Phys. Rev. D 81, 015011 (2010).

[19] W. Bernreuther, M. Flesch, and P. Haberl, Phys. Rev. D 58, 114031 (1998).

[20] D0 Collaboration, V. M. Abazov, et al., Phys. Rev. D

80_{, 071102 (2009).}

[21] The ATLAS coordinate system is right-handed with the pseudorapidity, η, defined as η = − ln[tan(θ/2)], where the polar angle θ is measured with respect to the LHC beamline. The azimuthal angle, φ, is measured with re-spect to the x-axis, which points towards the center of the LHC ring. The z-axis is parallel to the anti-clockwise beam viewed from above. Transverse momentum and

en-ergy are defined as pT= p sin θ and ET= E sin θ,

respec-tively.

[22] W. Bernreuther, A. Brandenburg, Z. G. Si, and P. Uwer, Nucl. Phys. B 690, 81 (2004).

[23] CDF Collaboration, T. Aaltonen, et al., Phys. Rev. D

83_{, 031104 (2011).}

[24] D0 Collaboration, V. M. Abazov, et al., Phys. Rev. Lett.

107, 032001 (2011).

[25] D0 Collaboration, V. M. Abazov, et al., Phys. Lett. B

702_{, 16 (2011).}

[26] D0 Collaboration, V. M. Abazov, et al., Phys. Rev. Lett.

108, 032004 (2012).

[27] S. Frixione and B. R. Webber, JHEP 06, 029 (2002). [28] S. Frixione, P. Nason, and B. Webber, JHEP 08, 007

(2003).

[29] S. Frixione, E. Laenen, P. Motylinski, and B. Webber, JHEP 03, 092 (2006).

[30] P. Nadolsky et al., Phys. Rev. D 78, 013004 (2008). [31] F. Hubaut et al., Eur. Phys. J. C 44S2, 13 (2005). [32] ATLAS Collaboration, arXiv:0901.0512 [hep-ex]. [33] ATLAS Collaboration, JINST 3, S08003 (2008).

[34] ATLAS Collaboration, Eur. Phys. J. C 71, 1630 (2011).

[35] ATLAS Collaboration, ATLAS-CONF-2011-116

https://cdsweb.cern.ch/record/1376384.

[36] GEANT4 Collaboration, Nucl. Instrum. Meth. A 506, 250 (2003).

[37] ATLAS Collaboration, Eur. Phys. J. C 70, 823 (2010). [38] G. Corcella et al., JHEP 01, 010 (2001).

[39] G. Corcella et al., arXiv:hep-ph/0210213.

[40] ATLAS Collaboration, Submitted to JHEP,

arXiv:1202.4892 [hep-ex].

[41] M. Cacciari, G. Salam, and G. Soyez, JHEP 04, 063 (2008).

[42] ATLAS Collaboration, Eur. Phys. J. C 72, 1844 (2012). [43] ATLAS Collaboration, Eur. Phys. J. C 71, 1577 (2011). [44] M. Aliev et al., Comput. Phys. Commun. 182, 1034

(2011).

[45] ATLAS Collaboration, Submitted to Eur. Phys. J. C, arXiv:1112.6426 [hep-ex].

[46] P. Nason, JHEP 11, 040 (2004).

[47] S. Frixione, P. Nason, and C. Oleari, JHEP 11, 070

(2007).

[48] S. Alioli, P. Nason, C. Oleari, and E. Re, JHEP 06, 043 (2010).

[49] T. Sjostrand, S. Mrenna, and P. Skands, JHEP 05, 026 (2006).

[50] B. Kersevan and E. Richter-Was, arXiv:hep-ph/0405247. [51] P. Z. Skands, Phys. Rev. D 82, 074018 (2010).

[52] A. D. Martin, W. J. Stirling, R. S. Thorne, and G. Watt, Eur. Phys. J. C 63, 189 (2009).

[53] R. D. Ball, L. Del Debbio, S. Forte, A. Guffanti, J. I. Latorre, et al., Nucl. Phys. B 838, 136 (2010).

[54] R. Campbell, J. Ellis and F. Tramontano, Phys. Rev. D

70, 094012 (2004).

[55] N. Kidonakis, arXiv:1005.3330 [hep-ph].

[56] J. Campbell and R. Ellis, Nucl. Phys. Proc. Suppl.

The ATLAS Collaboration

G. Aad48_{, B. Abbott}110_{, J. Abdallah}11_{, S. Abdel Khalek}114_{, A.A. Abdelalim}49_{, A. Abdesselam}117_{, O. Abdinov}10_, B. Abi111_{, M. Abolins}87_{, O.S. AbouZeid}157_{, H. Abramowicz}152_{, H. Abreu}114_{, E. Acerbi}88a,88b_{, B.S. Acharya}163a,163b_, L. Adamczyk37_{, D.L. Adams}24_{, T.N. Addy}56_{, J. Adelman}174_{, M. Aderholz}98_{, S. Adomeit}97_{, P. Adragna}74_,

T. Adye128_{, S. Aefsky}22_{, J.A. Aguilar-Saavedra}123b,a_{, M. Aharrouche}80_{, S.P. Ahlen}21_{, F. Ahles}48_{, A. Ahmad}147_, M. Ahsan40_{, G. Aielli}132a,132b_{, T. Akdogan}18a_{, T.P.A. ˚Akesson}78_{, G. Akimoto}154_{, A.V. Akimov}93_{, A. Akiyama}66_, M.S. Alam1_{, M.A. Alam}75_{, J. Albert}168_{, S. Albrand}55_{, M. Aleksa}29_{, I.N. Aleksandrov}64_{, F. Alessandria}88a_, C. Alexa25a_{, G. Alexander}152_{, G. Alexandre}49_{, T. Alexopoulos}9_{, M. Alhroob}20_{, M. Aliev}15_{, G. Alimonti}88a_, J. Alison119_{, M. Aliyev}10_{, B.M.M. Allbrooke}17_{, P.P. Allport}72_{, S.E. Allwood-Spiers}53_{, J. Almond}81_,

A. Aloisio101a,101b_{, R. Alon}170_{, A. Alonso}78_{, B. Alvarez Gonzalez}87_{, M.G. Alviggi}101a,101b_{, K. Amako}65_,

P. Amaral29_{, C. Amelung}22_{, V.V. Ammosov}127_{, A. Amorim}123a,b_{, G. Amor´os}166_{, N. Amram}152_{, C. Anastopoulos}29_, L.S. Ancu16_{, N. Andari}114_{, T. Andeen}34_{, C.F. Anders}20_{, G. Anders}58a_{, K.J. Anderson}30_{, A. Andreazza}88a,88b_, V. Andrei58a_{, M-L. Andrieux}55_{, X.S. Anduaga}69_{, A. Angerami}34_{, F. Anghinolfi}29_{, A. Anisenkov}106_{, N. Anjos}123a_, A. Annovi47_{, A. Antonaki}8_{, M. Antonelli}47_{, A. Antonov}95_{, J. Antos}143b_{, F. Anulli}131a_{, S. Aoun}82_{, L. Aperio Bella}4_, R. Apolle117,c_{, G. Arabidze}87_{, I. Aracena}142_{, Y. Arai}65_{, A.T.H. Arce}44_{, S. Arfaoui}147_{, J-F. Arguin}14_{, E. Arik}18a,∗_, M. Arik18a_{, A.J. Armbruster}86_{, O. Arnaez}80_{, V. Arnal}79_{, C. Arnault}114_{, A. Artamonov}94_{, G. Artoni}131a,131b_, D. Arutinov20_{, S. Asai}154_{, R. Asfandiyarov}171_{, S. Ask}27_{, B. ˚Asman}145a,145b_{, L. Asquith}5_{, K. Assamagan}24_, A. Astbury168_{, A. Astvatsatourov}52_{, B. Aubert}4_{, E. Auge}114_{, K. Augsten}126_{, M. Aurousseau}144a_{, G. Avolio}162_, R. Avramidou9_{, D. Axen}167_{, C. Ay}54_{, G. Azuelos}92,d_{, Y. Azuma}154_{, M.A. Baak}29_{, G. Baccaglioni}88a_,

C. Bacci133a,133b_{, A.M. Bach}14_{, H. Bachacou}135_{, K. Bachas}29_{, M. Backes}49_{, M. Backhaus}20_{, E. Badescu}25a_, P. Bagnaia131a,131b_{, S. Bahinipati}2_{, Y. Bai}32a_{, D.C. Bailey}157_{, T. Bain}157_{, J.T. Baines}128_{, O.K. Baker}174_, M.D. Baker24_{, S. Baker}76_{, E. Banas}38_{, P. Banerjee}92_{, Sw. Banerjee}171_{, D. Banfi}29_{, A. Bangert}149_{, V. Bansal}168_, H.S. Bansil17_{, L. Barak}170_{, S.P. Baranov}93_{, A. Barashkou}64_{, A. Barbaro Galtieri}14_{, T. Barber}48_{, E.L. Barberio}85_, D. Barberis50a,50b_{, M. Barbero}20_{, D.Y. Bardin}64_{, T. Barillari}98_{, M. Barisonzi}173_{, T. Barklow}142_{, N. Barlow}27_, B.M. Barnett128_{, R.M. Barnett}14_{, A. Baroncelli}133a_{, G. Barone}49_{, A.J. Barr}117_{, F. Barreiro}79_{, J. Barreiro Guimar˜aes} da Costa57_{, P. Barrillon}114_{, R. Bartoldus}142_{, A.E. Barton}70_{, V. Bartsch}148_{, R.L. Bates}53_{, L. Batkova}143a_,

J.R. Batley27_{, A. Battaglia}16_{, M. Battistin}29_{, F. Bauer}135_{, H.S. Bawa}142,e_{, S. Beale}97_{, T. Beau}77_,

P.H. Beauchemin160_{, R. Beccherle}50a_{, P. Bechtle}20_{, H.P. Beck}16_{, S. Becker}97_{, M. Beckingham}137_{, K.H. Becks}173_, A.J. Beddall18c_{, A. Beddall}18c_{, S. Bedikian}174_{, V.A. Bednyakov}64_{, C.P. Bee}82_{, M. Begel}24_{, S. Behar Harpaz}151_, P.K. Behera62_{, M. Beimforde}98_{, C. Belanger-Champagne}84_{, P.J. Bell}49_{, W.H. Bell}49_{, G. Bella}152_{, L. Bellagamba}19a_, F. Bellina29_{, M. Bellomo}29_{, A. Belloni}57_{, O. Beloborodova}106,f_{, K. Belotskiy}95_{, O. Beltramello}29_{, O. Benary}152_, D. Benchekroun134a_{, C. Benchouk}82_{, M. Bendel}80_{, N. Benekos}164_{, Y. Benhammou}152_{, E. Benhar Noccioli}49_, J.A. Benitez Garcia158b_{, D.P. Benjamin}44_{, M. Benoit}114_{, J.R. Bensinger}22_{, K. Benslama}129_{, S. Bentvelsen}104_, D. Berge29_{, E. Bergeaas Kuutmann}41_{, N. Berger}4_{, F. Berghaus}168_{, E. Berglund}104_{, J. Beringer}14_{, P. Bernat}76_, R. Bernhard48, C. Bernius24, T. Berry75, C. Bertella82, A. Bertin19a,19b, F. Bertinelli29, F. Bertolucci121a,121b, M.I. Besana88a,88b_{, N. Besson}135_{, S. Bethke}98_{, W. Bhimji}45_{, R.M. Bianchi}29_{, M. Bianco}71a,71b_{, O. Biebel}97_, S.P. Bieniek76_{, K. Bierwagen}54_{, J. Biesiada}14_{, M. Biglietti}133a_{, H. Bilokon}47_{, M. Bindi}19a,19b_{, S. Binet}114_, A. Bingul18c_{, C. Bini}131a,131b_{, C. Biscarat}176_{, U. Bitenc}48_{, K.M. Black}21_{, R.E. Blair}5_{, J.-B. Blanchard}135_, G. Blanchot29_{, T. Blazek}143a_{, C. Blocker}22_{, J. Blocki}38_{, A. Blondel}49_{, W. Blum}80_{, U. Blumenschein}54_,

G.J. Bobbink104_{, V.B. Bobrovnikov}106_{, S.S. Bocchetta}78_{, A. Bocci}44_{, C.R. Boddy}117_{, M. Boehler}41_{, J. Boek}173_, N. Boelaert35_{, J.A. Bogaerts}29_{, A. Bogdanchikov}106_{, A. Bogouch}89,∗_{, C. Bohm}145a_{, J. Bohm}124_{, V. Boisvert}75_, T. Bold37_{, V. Boldea}25a_{, N.M. Bolnet}135_{, M. Bomben}77_{, M. Bona}74_{, V.G. Bondarenko}95_{, M. Bondioli}162_, M. Boonekamp135_{, C.N. Booth}138_{, S. Bordoni}77_{, C. Borer}16_{, A. Borisov}127_{, G. Borissov}70_{, I. Borjanovic}12a_, M. Borri81_{, S. Borroni}86_{, V. Bortolotto}133a,133b_{, K. Bos}104_{, D. Boscherini}19a_{, M. Bosman}11_{, H. Boterenbrood}104_, D. Botterill128_{, J. Bouchami}92_{, J. Boudreau}122_{, E.V. Bouhova-Thacker}70_{, D. Boumediene}33_{, C. Bourdarios}114_, N. Bousson82_{, A. Boveia}30_{, J. Boyd}29_{, I.R. Boyko}64_{, N.I. Bozhko}127_{, I. Bozovic-Jelisavcic}12b_{, J. Bracinik}17_, A. Braem29_{, P. Branchini}133a_{, G.W. Brandenburg}57_{, A. Brandt}7_{, G. Brandt}117_{, O. Brandt}54_{, U. Bratzler}155_,

B. Brau83_{, J.E. Brau}113_{, H.M. Braun}173_{, B. Brelier}157_{, J. Bremer}29_{, K. Brendlinger}119_{, R. Brenner}165_{, S. Bressler}170_, D. Britton53_{, F.M. Brochu}27_{, I. Brock}20_{, R. Brock}87_{, T.J. Brodbeck}70_{, E. Brodet}152_{, F. Broggi}88a_{, C. Bromberg}87_, J. Bronner98_{, G. Brooijmans}34_{, W.K. Brooks}31b_{, G. Brown}81_{, H. Brown}7_{, P.A. Bruckman de Renstrom}38_,

D. Bruncko143b_{, R. Bruneliere}48_{, S. Brunet}60_{, A. Bruni}19a_{, G. Bruni}19a_{, M. Bruschi}19a_{, T. Buanes}13_{, Q. Buat}55_, F. Bucci49_{, J. Buchanan}117_{, N.J. Buchanan}2_{, P. Buchholz}140_{, R.M. Buckingham}117_{, A.G. Buckley}45_{, S.I. Buda}25a_, I.A. Budagov64_{, B. Budick}107_{, V. B¨uscher}80_{, L. Bugge}116_{, O. Bulekov}95_{, M. Bunse}42_{, T. Buran}116_{, H. Burckhart}29_, S. Burdin72_{, T. Burgess}13_{, S. Burke}128_{, E. Busato}33_{, P. Bussey}53_{, C.P. Buszello}165_{, F. Butin}29_{, B. Butler}142_, J.M. Butler21_{, C.M. Buttar}53_{, J.M. Butterworth}76_{, W. Buttinger}27_{, S. Cabrera Urb´an}166_{, D. Caforio}19a,19b_,

O. Cakir3a_{, P. Calafiura}14_{, G. Calderini}77_{, P. Calfayan}97_{, R. Calkins}105_{, L.P. Caloba}23a_{, R. Caloi}131a,131b_, D. Calvet33_{, S. Calvet}33_{, R. Camacho Toro}33_{, P. Camarri}132a,132b_{, M. Cambiaghi}118a,118b_{, D. Cameron}116_,

L.M. Caminada14_{, S. Campana}29_{, M. Campanelli}76_{, V. Canale}101a,101b_{, F. Canelli}30,g_{, A. Canepa}158a_{, J. Cantero}79_, L. Capasso101a,101b_{, M.D.M. Capeans Garrido}29_{, I. Caprini}25a_{, M. Caprini}25a_{, D. Capriotti}98_{, M. Capua}36a,36b_, R. Caputo80_{, R. Cardarelli}132a_{, T. Carli}29_{, G. Carlino}101a_{, L. Carminati}88a,88b_{, B. Caron}84_{, S. Caron}103_, E. Carquin31b_{, G.D. Carrillo Montoya}171_{, A.A. Carter}74_{, J.R. Carter}27_{, J. Carvalho}123a,h_{, D. Casadei}107_, M.P. Casado11_{, M. Cascella}121a,121b_{, C. Caso}50a,50b,∗_{, A.M. Castaneda Hernandez}171_{, E. Castaneda-Miranda}171_, V. Castillo Gimenez166_{, N.F. Castro}123a_{, G. Cataldi}71a_{, F. Cataneo}29_{, A. Catinaccio}29_{, J.R. Catmore}29_{, A. Cattai}29_, G. Cattani132a,132b_{, S. Caughron}87_{, D. Cauz}163a,163c_{, P. Cavalleri}77_{, D. Cavalli}88a_{, M. Cavalli-Sforza}11_,

V. Cavasinni121a,121b_{, F. Ceradini}133a,133b_{, A.S. Cerqueira}23b_{, A. Cerri}29_{, L. Cerrito}74_{, F. Cerutti}47_{, S.A. Cetin}18b_, F. Cevenini101a,101b_{, A. Chafaq}134a_{, D. Chakraborty}105_{, K. Chan}2_{, B. Chapleau}84_{, J.D. Chapman}27_,

J.W. Chapman86_{, E. Chareyre}77_{, D.G. Charlton}17_{, V. Chavda}81_{, C.A. Chavez Barajas}29_{, S. Cheatham}84_, S. Chekanov5_{, S.V. Chekulaev}158a_{, G.A. Chelkov}64_{, M.A. Chelstowska}103_{, C. Chen}63_{, H. Chen}24_{, S. Chen}32c_, T. Chen32c_{, X. Chen}171_{, S. Cheng}32a_{, A. Cheplakov}64_{, V.F. Chepurnov}64_{, R. Cherkaoui El Moursli}134e_,

V. Chernyatin24_{, E. Cheu}6_{, S.L. Cheung}157_{, L. Chevalier}135_{, G. Chiefari}101a,101b_{, L. Chikovani}51a_{, J.T. Childers}29_, A. Chilingarov70_{, G. Chiodini}71a_{, A.S. Chisholm}17_{, R.T. Chislett}76_{, M.V. Chizhov}64_{, G. Choudalakis}30_,

S. Chouridou136_{, I.A. Christidi}76_{, A. Christov}48_{, D. Chromek-Burckhart}29_{, M.L. Chu}150_{, J. Chudoba}124_, G. Ciapetti131a,131b_{, A.K. Ciftci}3a_{, R. Ciftci}3a_{, D. Cinca}33_{, V. Cindro}73_{, M.D. Ciobotaru}162_{, C. Ciocca}19a_,

A. Ciocio14_{, M. Cirilli}86_{, M. Citterio}88a_{, M. Ciubancan}25a_{, A. Clark}49_{, P.J. Clark}45_{, W. Cleland}122_{, J.C. Clemens}82_, B. Clement55_{, C. Clement}145a,145b_{, R.W. Clifft}128_{, Y. Coadou}82_{, M. Cobal}163a,163c_{, A. Coccaro}171_{, J. Cochran}63_, P. Coe117, J.G. Cogan142, J. Coggeshall164, E. Cogneras176, J. Colas4, A.P. Colijn104, N.J. Collins17,

C. Collins-Tooth53_{, J. Collot}55_{, G. Colon}83_{, P. Conde Mui˜no}123a_{, E. Coniavitis}117_{, M.C. Conidi}11_{, M. Consonni}103_, S.M. Consonni88a,88b_{, V. Consorti}48_{, S. Constantinescu}25a_{, C. Conta}118a,118b_{, G. Conti}57_{, F. Conventi}101a,i_, J. Cook29_{, M. Cooke}14_{, B.D. Cooper}76_{, A.M. Cooper-Sarkar}117_{, K. Copic}14_{, T. Cornelissen}173_{, M. Corradi}19a_, F. Corriveau84,j_{, A. Cortes-Gonzalez}164_{, G. Cortiana}98_{, G. Costa}88a_{, M.J. Costa}166_{, D. Costanzo}138_{, T. Costin}30_, D. Cˆot´e29_{, R. Coura Torres}23a_{, L. Courneyea}168_{, G. Cowan}75_{, C. Cowden}27_{, B.E. Cox}81_{, K. Cranmer}107_,

F. Crescioli121a,121b_{, M. Cristinziani}20_{, G. Crosetti}36a,36b_{, R. Crupi}71a,71b_{, S. Cr´ep´e-Renaudin}55_{, C.-M. Cuciuc}25a_, C. Cuenca Almenar174_{, T. Cuhadar Donszelmann}138_{, M. Curatolo}47_{, C.J. Curtis}17_{, C. Cuthbert}149_{, P. Cwetanski}60_, H. Czirr140_{, P. Czodrowski}43_{, Z. Czyczula}174_{, S. D’Auria}53_{, M. D’Onofrio}72_{, A. D’Orazio}131a,131b_,

P.V.M. Da Silva23a_{, C. Da Via}81_{, W. Dabrowski}37_{, A. Dafinca}117_{, T. Dai}86_{, C. Dallapiccola}83_{, M. Dam}35_, M. Dameri50a,50b_{, D.S. Damiani}136_{, H.O. Danielsson}29_{, D. Dannheim}98_{, V. Dao}49_{, G. Darbo}50a_{, G.L. Darlea}25b_, W. Davey20_{, T. Davidek}125_{, N. Davidson}85_{, R. Davidson}70_{, E. Davies}117,c_{, M. Davies}92_{, A.R. Davison}76_, Y. Davygora58a_{, E. Dawe}141_{, I. Dawson}138_{, J.W. Dawson}5,∗_{, R.K. Daya-Ishmukhametova}22_{, K. De}7_, R. de Asmundis101a_{, S. De Castro}19a,19b_{, P.E. De Castro Faria Salgado}24_{, S. De Cecco}77_{, J. de Graat}97_, N. De Groot103, P. de Jong104, C. De La Taille114, H. De la Torre79, B. De Lotto163a,163c, L. de Mora70,

L. De Nooij104, D. De Pedis131a, A. De Salvo131a, U. De Sanctis163a,163c, A. De Santo148, J.B. De Vivie De Regie114, G. De Zorzi131a,131b, S. Dean76, W.J. Dearnaley70, R. Debbe24, C. Debenedetti45, B. Dechenaux55, D.V. Dedovich64, J. Degenhardt119_{, M. Dehchar}117_{, C. Del Papa}163a,163c_{, J. Del Peso}79_{, T. Del Prete}121a,121b_{, T. Delemontex}55_, M. Deliyergiyev73_{, A. Dell’Acqua}29_{, L. Dell’Asta}21_{, M. Della Pietra}101a,i_{, D. della Volpe}101a,101b_{, M. Delmastro}4_, N. Delruelle29_{, P.A. Delsart}55_{, C. Deluca}147_{, S. Demers}174_{, M. Demichev}64_{, B. Demirkoz}11,k_{, J. Deng}162_,

S.P. Denisov127_{, D. Derendarz}38_{, J.E. Derkaoui}134d_{, F. Derue}77_{, P. Dervan}72_{, K. Desch}20_{, E. Devetak}147_, P.O. Deviveiros104_{, A. Dewhurst}128_{, B. DeWilde}147_{, S. Dhaliwal}157_{, R. Dhullipudi}24 ,l_{, A. Di Ciaccio}132a,132b_, L. Di Ciaccio4_{, A. Di Girolamo}29_{, B. Di Girolamo}29_{, S. Di Luise}133a,133b_{, A. Di Mattia}171_{, B. Di Micco}29_, R. Di Nardo47_{, A. Di Simone}132a,132b_{, R. Di Sipio}19a,19b_{, M.A. Diaz}31a_{, F. Diblen}18c_{, E.B. Diehl}86_{, J. Dietrich}41_, T.A. Dietzsch58a_{, S. Diglio}85_{, K. Dindar Yagci}39_{, J. Dingfelder}20_{, C. Dionisi}131a,131b_{, P. Dita}25a_{, S. Dita}25a_, F. Dittus29_{, F. Djama}82_{, T. Djobava}51b_{, M.A.B. do Vale}23c_{, A. Do Valle Wemans}123a_{, T.K.O. Doan}4_{, M. Dobbs}84_, R. Dobinson29,∗_{, D. Dobos}29_{, E. Dobson}29,m_{, J. Dodd}34_{, C. Doglioni}49_{, T. Doherty}53_{, Y. Doi}65,∗_{, J. Dolejsi}125_, I. Dolenc73_{, Z. Dolezal}125_{, B.A. Dolgoshein}95,∗_{, T. Dohmae}154_{, M. Donadelli}23d_{, M. Donega}119_{, J. Donini}33_, J. Dopke29_{, A. Doria}101a_{, A. Dos Anjos}171_{, M. Dosil}11_{, A. Dotti}121a,121b_{, M.T. Dova}69_{, J.D. Dowell}17_,

A.D. Doxiadis104_{, A.T. Doyle}53_{, Z. Drasal}125_{, J. Drees}173_{, N. Dressnandt}119_{, H. Drevermann}29_{, C. Driouichi}35_, M. Dris9_{, J. Dubbert}98_{, S. Dube}14_{, E. Duchovni}170_{, G. Duckeck}97_{, A. Dudarev}29_{, F. Dudziak}63_{, M. D¨uhrssen}29_, I.P. Duerdoth81_{, L. Duflot}114_{, M-A. Dufour}84_{, M. Dunford}29_{, H. Duran Yildiz}3a_{, R. Duxfield}138_{, M. Dwuznik}37_, F. Dydak29_{, M. D¨uren}52_{, W.L. Ebenstein}44_{, J. Ebke}97_{, S. Eckweiler}80_{, K. Edmonds}80_{, C.A. Edwards}75_, N.C. Edwards53_{, W. Ehrenfeld}41_{, T. Ehrich}98_{, T. Eifert}142_{, G. Eigen}13_{, K. Einsweiler}14_{, E. Eisenhandler}74_, T. Ekelof165_{, M. El Kacimi}134c_{, M. Ellert}165_{, S. Elles}4_{, F. Ellinghaus}80_{, K. Ellis}74_{, N. Ellis}29_{, J. Elmsheuser}97_, M. Elsing29_{, D. Emeliyanov}128_{, R. Engelmann}147_{, A. Engl}97_{, B. Epp}61_{, A. Eppig}86_{, J. Erdmann}54_{, A. Ereditato}16_,

D. Eriksson145a_{, J. Ernst}1_{, M. Ernst}24_{, J. Ernwein}135_{, D. Errede}164_{, S. Errede}164_{, E. Ertel}80_{, M. Escalier}114_, C. Escobar122_{, X. Espinal Curull}11_{, B. Esposito}47_{, F. Etienne}82_{, A.I. Etienvre}135_{, E. Etzion}152_{, D. Evangelakou}54_, H. Evans60_{, L. Fabbri}19a,19b_{, C. Fabre}29_{, R.M. Fakhrutdinov}127_{, S. Falciano}131a_{, Y. Fang}171_{, M. Fanti}88a,88b_, A. Farbin7_{, A. Farilla}133a_{, J. Farley}147_{, T. Farooque}157_{, S. Farrell}162_{, S.M. Farrington}117_{, P. Farthouat}29_, P. Fassnacht29_{, D. Fassouliotis}8_{, B. Fatholahzadeh}157_{, A. Favareto}88a,88b_{, L. Fayard}114_{, S. Fazio}36a,36b_,

R. Febbraro33_{, P. Federic}143a_{, O.L. Fedin}120_{, W. Fedorko}87_{, M. Fehling-Kaschek}48_{, L. Feligioni}82_{, D. Fellmann}5_, C. Feng32d_{, E.J. Feng}30_{, A.B. Fenyuk}127_{, J. Ferencei}143b_{, J. Ferland}92_{, W. Fernando}108_{, S. Ferrag}53_{, J. Ferrando}53_, V. Ferrara41_{, A. Ferrari}165_{, P. Ferrari}104_{, R. Ferrari}118a_{, D.E. Ferreira de Lima}53_{, A. Ferrer}166_{, M.L. Ferrer}47_, D. Ferrere49_{, C. Ferretti}86_{, A. Ferretto Parodi}50a,50b_{, M. Fiascaris}30_{, F. Fiedler}80_{, A. Filipˇciˇc}73_{, A. Filippas}9_, F. Filthaut103_{, M. Fincke-Keeler}168_{, M.C.N. Fiolhais}123a,h_{, L. Fiorini}166_{, A. Firan}39_{, G. Fischer}41_{, P. Fischer}20_, M.J. Fisher108_{, M. Flechl}48_{, I. Fleck}140_{, J. Fleckner}80_{, P. Fleischmann}172_{, S. Fleischmann}173_{, T. Flick}173_, A. Floderus78_{, L.R. Flores Castillo}171_{, M.J. Flowerdew}98_{, M. Fokitis}9_{, T. Fonseca Martin}16_{, D.A. Forbush}137_, A. Formica135_{, A. Forti}81_{, D. Fortin}158a_{, J.M. Foster}81_{, D. Fournier}114_{, A. Foussat}29_{, A.J. Fowler}44_{, K. Fowler}136_, H. Fox70_{, P. Francavilla}11_{, S. Franchino}118a,118b_{, D. Francis}29_{, T. Frank}170_{, M. Franklin}57_{, S. Franz}29_,

M. Fraternali118a,118b_{, S. Fratina}119_{, S.T. French}27_{, F. Friedrich}43_{, R. Froeschl}29_{, D. Froidevaux}29_{, J.A. Frost}27_, C. Fukunaga155_{, E. Fullana Torregrosa}29_{, J. Fuster}166_{, C. Gabaldon}29_{, O. Gabizon}170_{, T. Gadfort}24_{, S. Gadomski}49_, G. Gagliardi50a,50b_{, P. Gagnon}60_{, C. Galea}97_{, E.J. Gallas}117_{, V. Gallo}16_{, B.J. Gallop}128_{, P. Gallus}124_{, K.K. Gan}108_, Y.S. Gao142,e_{, V.A. Gapienko}127_{, A. Gaponenko}14_{, F. Garberson}174_{, M. Garcia-Sciveres}14_{, C. Garc´ıa}166_{, J.E. Garc´ıa} Navarro166_{, R.W. Gardner}30_{, N. Garelli}29_{, H. Garitaonandia}104_{, V. Garonne}29_{, J. Garvey}17_{, C. Gatti}47_,

G. Gaudio118a_{, B. Gaur}140_{, L. Gauthier}135_{, P. Gauzzi}131a,131b_{, I.L. Gavrilenko}93_{, C. Gay}167_{, G. Gaycken}20_,

J-C. Gayde29, E.N. Gazis9, P. Ge32d, C.N.P. Gee128, D.A.A. Geerts104, Ch. Geich-Gimbel20, K. Gellerstedt145a,145b, C. Gemme50a_{, A. Gemmell}53_{, M.H. Genest}55_{, S. Gentile}131a,131b_{, M. George}54_{, S. George}75_{, P. Gerlach}173_,

A. Gershon152_{, C. Geweniger}58a_{, H. Ghazlane}134b_{, N. Ghodbane}33_{, B. Giacobbe}19a_{, S. Giagu}131a,131b_,

V. Giakoumopoulou8_{, V. Giangiobbe}11_{, F. Gianotti}29_{, B. Gibbard}24_{, A. Gibson}157_{, S.M. Gibson}29_{, L.M. Gilbert}117_, V. Gilewsky90_{, D. Gillberg}28_{, A.R. Gillman}128_{, D.M. Gingrich}2,d_{, J. Ginzburg}152_{, N. Giokaris}8_{, M.P. Giordani}163c_, R. Giordano101a,101b_{, F.M. Giorgi}15_{, P. Giovannini}98_{, P.F. Giraud}135_{, D. Giugni}88a_{, M. Giunta}92_{, P. Giusti}19a_, B.K. Gjelsten116_{, L.K. Gladilin}96_{, C. Glasman}79_{, J. Glatzer}48_{, A. Glazov}41_{, K.W. Glitza}173_{, G.L. Glonti}64_, J.R. Goddard74_{, J. Godfrey}141_{, J. Godlewski}29_{, M. Goebel}41_{, T. G¨opfert}43_{, C. Goeringer}80_{, C. G¨ossling}42_, T. G¨ottfert98_{, S. Goldfarb}86_{, T. Golling}174_{, A. Gomes}123a,b_{, L.S. Gomez Fajardo}41_{, R. Gon¸calo}75_,

J. Goncalves Pinto Firmino Da Costa41_{, L. Gonella}20_{, A. Gonidec}29_{, S. Gonzalez}171_{, S. Gonz´alez de la Hoz}166_, G. Gonzalez Parra11_{, M.L. Gonzalez Silva}26_{, S. Gonzalez-Sevilla}49_{, J.J. Goodson}147_{, L. Goossens}29_,

P.A. Gorbounov94_{, H.A. Gordon}24_{, I. Gorelov}102_{, G. Gorfine}173_{, B. Gorini}29_{, E. Gorini}71a,71b_{, A. Goriˇsek}73_, E. Gornicki38_{, S.A. Gorokhov}127_{, V.N. Goryachev}127_{, B. Gosdzik}41_{, M. Gosselink}104_{, M.I. Gostkin}64_, I. Gough Eschrich162_{, M. Gouighri}134a_{, D. Goujdami}134c_{, M.P. Goulette}49_{, A.G. Goussiou}137_{, C. Goy}4_, S. Gozpinar22, I. Grabowska-Bold37, P. Grafstr¨om29, K-J. Grahn41, F. Grancagnolo71a, S. Grancagnolo15, V. Grassi147, V. Gratchev120, N. Grau34, H.M. Gray29, J.A. Gray147, E. Graziani133a, O.G. Grebenyuk120, T. Greenshaw72, Z.D. Greenwood24,l, K. Gregersen35, I.M. Gregor41, P. Grenier142, J. Griffiths137,

N. Grigalashvili64_{, A.A. Grillo}136_{, S. Grinstein}11_{, Y.V. Grishkevich}96_{, J.-F. Grivaz}114_{, M. Groh}98_{, E. Gross}170_, J. Grosse-Knetter54_{, J. Groth-Jensen}170_{, K. Grybel}140_{, V.J. Guarino}5_{, D. Guest}174_{, C. Guicheney}33_,

A. Guida71a,71b_{, S. Guindon}54_{, H. Guler}84,n_{, J. Gunther}124_{, B. Guo}157_{, J. Guo}34_{, A. Gupta}30_{, Y. Gusakov}64_, V.N. Gushchin127_{, P. Gutierrez}110_{, N. Guttman}152_{, O. Gutzwiller}171_{, C. Guyot}135_{, C. Gwenlan}117_{, C.B. Gwilliam}72_, A. Haas142_{, S. Haas}29_{, C. Haber}14_{, H.K. Hadavand}39_{, D.R. Hadley}17_{, P. Haefner}98_{, F. Hahn}29_{, S. Haider}29_,

Z. Hajduk38_{, H. Hakobyan}175_{, D. Hall}117_{, J. Haller}54_{, K. Hamacher}173_{, P. Hamal}112_{, M. Hamer}54_,

A. Hamilton144b,o_{, S. Hamilton}160_{, H. Han}32a_{, L. Han}32b_{, K. Hanagaki}115_{, K. Hanawa}159_{, M. Hance}14_{, C. Handel}80_, P. Hanke58a_{, J.R. Hansen}35_{, J.B. Hansen}35_{, J.D. Hansen}35_{, P.H. Hansen}35_{, P. Hansson}142_{, K. Hara}159_{, G.A. Hare}136_, T. Harenberg173_{, S. Harkusha}89_{, D. Harper}86_{, R.D. Harrington}45_{, O.M. Harris}137_{, K. Harrison}17_{, J. Hartert}48_, F. Hartjes104_{, T. Haruyama}65_{, A. Harvey}56_{, S. Hasegawa}100_{, Y. Hasegawa}139_{, S. Hassani}135_{, M. Hatch}29_{, D. Hauff}98_, S. Haug16_{, M. Hauschild}29_{, R. Hauser}87_{, M. Havranek}20_{, B.M. Hawes}117_{, C.M. Hawkes}17_{, R.J. Hawkings}29_,

A.D. Hawkins78_{, D. Hawkins}162_{, T. Hayakawa}66_{, T. Hayashi}159_{, D. Hayden}75_{, H.S. Hayward}72_{, S.J. Haywood}128_, E. Hazen21_{, M. He}32d_{, S.J. Head}17_{, V. Hedberg}78_{, L. Heelan}7_{, S. Heim}87_{, B. Heinemann}14_{, S. Heisterkamp}35_, L. Helary4_{, C. Heller}97_{, M. Heller}29_{, S. Hellman}145a,145b_{, D. Hellmich}20_{, C. Helsens}11_{, R.C.W. Henderson}70_, M. Henke58a_{, A. Henrichs}54_{, A.M. Henriques Correia}29_{, S. Henrot-Versille}114_{, F. Henry-Couannier}82_{, C. Hensel}54_, T. Henß173_{, C.M. Hernandez}7_{, Y. Hern´andez Jim´enez}166_{, R. Herrberg}15_{, A.D. Hershenhorn}151_{, G. Herten}48_, R. Hertenberger97_{, L. Hervas}29_{, G.G. Hesketh}76_{, N.P. Hessey}104_{, E. Hig´on-Rodriguez}166_{, D. Hill}5,∗_{, J.C. Hill}27_, N. Hill5_{, K.H. Hiller}41_{, S. Hillert}20_{, S.J. Hillier}17_{, I. Hinchliffe}14_{, E. Hines}119_{, M. Hirose}115_{, F. Hirsch}42_,

J. Hoffman39_{, D. Hoffmann}82_{, M. Hohlfeld}80_{, M. Holder}140_{, S.O. Holmgren}145a_{, T. Holy}126_{, J.L. Holzbauer}87_, Y. Homma66_{, T.M. Hong}119_{, L. Hooft van Huysduynen}107_{, T. Horazdovsky}126_{, C. Horn}142_{, S. Horner}48_, J-Y. Hostachy55_{, S. Hou}150_{, M.A. Houlden}72_{, A. Hoummada}134a_{, J. Howarth}81_{, D.F. Howell}117_{, I. Hristova}15_, J. Hrivnac114_{, I. Hruska}124_{, T. Hryn’ova}4_{, P.J. Hsu}80_{, S.-C. Hsu}14_{, G.S. Huang}110_{, Z. Hubacek}126_{, F. Hubaut}82_, F. Huegging20_{, A. Huettmann}41_{, T.B. Huffman}117_{, E.W. Hughes}34_{, G. Hughes}70_{, R.E. Hughes-Jones}81_,

M. Huhtinen29_{, P. Hurst}57_{, M. Hurwitz}14_{, U. Husemann}41_{, N. Huseynov}64,p_{, J. Huston}87_{, J. Huth}57_{, G. Iacobucci}49_, G. Iakovidis9_{, M. Ibbotson}81_{, I. Ibragimov}140_{, R. Ichimiya}66_{, L. Iconomidou-Fayard}114_{, J. Idarraga}114_{, P. Iengo}101a_, O. Igonkina104_{, Y. Ikegami}65_{, M. Ikeno}65_{, Y. Ilchenko}39_{, D. Iliadis}153_{, N. Ilic}157_{, M. Imori}154_{, T. Ince}20_,

J. Inigo-Golfin29_{, P. Ioannou}8_{, M. Iodice}133a_{, V. Ippolito}131a,131b_{, A. Irles Quiles}166_{, C. Isaksson}165_{, A. Ishikawa}66_, M. Ishino67_{, R. Ishmukhametov}39_{, C. Issever}117_{, S. Istin}18a_{, A.V. Ivashin}127_{, W. Iwanski}38_{, H. Iwasaki}65_,

J.M. Izen40_{, V. Izzo}101a_{, B. Jackson}119_{, J.N. Jackson}72_{, P. Jackson}142_{, M.R. Jaekel}29_{, V. Jain}60_{, K. Jakobs}48_, S. Jakobsen35_{, J. Jakubek}126_{, D.K. Jana}110_{, E. Jankowski}157_{, E. Jansen}76_{, H. Jansen}29_{, A. Jantsch}98_{, M. Janus}48_, G. Jarlskog78_{, L. Jeanty}57_{, K. Jelen}37_{, I. Jen-La Plante}30_{, P. Jenni}29_{, A. Jeremie}4_{, P. Jeˇz}35_{, S. J´ez´equel}4_,

M.K. Jha19a_{, H. Ji}171_{, W. Ji}80_{, J. Jia}147_{, Y. Jiang}32b_{, M. Jimenez Belenguer}41_{, G. Jin}32b_{, S. Jin}32a_{, O. Jinnouchi}156_, M.D. Joergensen35_{, D. Joffe}39_{, L.G. Johansen}13_{, M. Johansen}145a,145b_{, K.E. Johansson}145a_{, P. Johansson}138_,

S. Johnert41_{, K.A. Johns}6_{, K. Jon-And}145a,145b_{, G. Jones}117_{, R.W.L. Jones}70_{, T.W. Jones}76_{, T.J. Jones}72_, O. Jonsson29_{, C. Joram}29_{, P.M. Jorge}123a_{, J. Joseph}14_{, J. Jovicevic}146_{, T. Jovin}12b_{, X. Ju}171_{, C.A. Jung}42_, R.M. Jungst29_{, V. Juranek}124_{, P. Jussel}61_{, A. Juste Rozas}11_{, V.V. Kabachenko}127_{, S. Kabana}16_{, M. Kaci}166_, A. Kaczmarska38_{, P. Kadlecik}35_{, M. Kado}114_{, H. Kagan}108_{, M. Kagan}57_{, S. Kaiser}98_{, E. Kajomovitz}151_, S. Kalinin173_{, L.V. Kalinovskaya}64_{, S. Kama}39_{, N. Kanaya}154_{, M. Kaneda}29_{, S. Kaneti}27_{, T. Kanno}156_, V.A. Kantserov95, J. Kanzaki65, B. Kaplan174, A. Kapliy30, J. Kaplon29, D. Kar43, M. Karagounis20,

M. Karagoz117_{, M. Karnevskiy}41_{, K. Karr}5_{, V. Kartvelishvili}70_{, A.N. Karyukhin}127_{, L. Kashif}171_{, G. Kasieczka}58b_, R.D. Kass108_{, A. Kastanas}13_{, M. Kataoka}4_{, Y. Kataoka}154_{, E. Katsoufis}9_{, J. Katzy}41_{, V. Kaushik}6_{, K. Kawagoe}66_, T. Kawamoto154_{, G. Kawamura}80_{, M.S. Kayl}104_{, V.A. Kazanin}106_{, M.Y. Kazarinov}64_{, R. Keeler}168_{, R. Kehoe}39_, M. Keil54_{, G.D. Kekelidze}64_{, J.S. Keller}137_{, J. Kennedy}97_{, M. Kenyon}53_{, O. Kepka}124_{, N. Kerschen}29_,

B.P. Kerˇsevan73_{, S. Kersten}173_{, K. Kessoku}154_{, J. Keung}157_{, F. Khalil-zada}10_{, H. Khandanyan}164_{, A. Khanov}111_, D. Kharchenko64_{, A. Khodinov}95_{, A.G. Kholodenko}127_{, A. Khomich}58a_{, T.J. Khoo}27_{, G. Khoriauli}20_,

A. Khoroshilov173_{, N. Khovanskiy}64_{, V. Khovanskiy}94_{, E. Khramov}64_{, J. Khubua}51b_{, H. Kim}145a,145b_{, M.S. Kim}2_, S.H. Kim159_{, N. Kimura}169_{, O. Kind}15_{, B.T. King}72_{, M. King}66_{, R.S.B. King}117_{, J. Kirk}128_{, L.E. Kirsch}22_, A.E. Kiryunin98_{, T. Kishimoto}66_{, D. Kisielewska}37_{, T. Kittelmann}122_{, A.M. Kiver}127_{, E. Kladiva}143b_,

J. Klaiber-Lodewigs42_{, M. Klein}72_{, U. Klein}72_{, K. Kleinknecht}80_{, M. Klemetti}84_{, A. Klier}170_{, P. Klimek}145a,145b_, A. Klimentov24_{, R. Klingenberg}42_{, J.A. Klinger}81_{, E.B. Klinkby}35_{, T. Klioutchnikova}29_{, P.F. Klok}103_{, S. Klous}104_, E.-E. Kluge58a_{, T. Kluge}72_{, P. Kluit}104_{, S. Kluth}98_{, N.S. Knecht}157_{, E. Kneringer}61_{, J. Knobloch}29_,

E.B.F.G. Knoops82_{, A. Knue}54_{, B.R. Ko}44_{, T. Kobayashi}154_{, M. Kobel}43_{, M. Kocian}142_{, P. Kodys}125_{, K. K¨oneke}29_, A.C. K¨onig103, S. Koenig80, L. K¨opke80, F. Koetsveld103, P. Koevesarki20, T. Koffas28, E. Koffeman104,

L.A. Kogan117, F. Kohn54, Z. Kohout126, T. Kohriki65, T. Koi142, T. Kokott20, G.M. Kolachev106, H. Kolanoski15, V. Kolesnikov64, I. Koletsou88a, J. Koll87, M. Kollefrath48, S.D. Kolya81, A.A. Komar93, Y. Komori154, T. Kondo65, T. Kono41,q_{, A.I. Kononov}48_{, R. Konoplich}107,r_{, N. Konstantinidis}76_{, A. Kootz}173_{, S. Koperny}37_{, K. Korcyl}38_, K. Kordas153_{, V. Koreshev}127_{, A. Korn}117_{, A. Korol}106_{, I. Korolkov}11_{, E.V. Korolkova}138_{, V.A. Korotkov}127_, O. Kortner98_{, S. Kortner}98_{, V.V. Kostyukhin}20_{, M.J. Kotam¨aki}29_{, S. Kotov}98_{, V.M. Kotov}64_{, A. Kotwal}44_, C. Kourkoumelis8_{, V. Kouskoura}153_{, A. Koutsman}158a_{, R. Kowalewski}168_{, T.Z. Kowalski}37_{, W. Kozanecki}135_, A.S. Kozhin127_{, V. Kral}126_{, V.A. Kramarenko}96_{, G. Kramberger}73_{, M.W. Krasny}77_{, A. Krasznahorkay}107_,

J. Kraus87_{, J.K. Kraus}20_{, A. Kreisel}152_{, F. Krejci}126_{, J. Kretzschmar}72_{, N. Krieger}54_{, P. Krieger}157_{, K. Kroeninger}54_, H. Kroha98_{, J. Kroll}119_{, J. Kroseberg}20_{, J. Krstic}12a_{, U. Kruchonak}64_{, H. Kr¨uger}20_{, T. Kruker}16_{, N. Krumnack}63_, Z.V. Krumshteyn64_{, A. Kruth}20_{, T. Kubota}85_{, S. Kuday}3a_{, S. Kuehn}48_{, A. Kugel}58c_{, T. Kuhl}41_{, D. Kuhn}61_,

V. Kukhtin64_{, Y. Kulchitsky}89_{, S. Kuleshov}31b_{, C. Kummer}97_{, M. Kuna}77_{, N. Kundu}117_{, J. Kunkle}119_{, A. Kupco}124_, H. Kurashige66_{, M. Kurata}159_{, Y.A. Kurochkin}89_{, V. Kus}124_{, E.S. Kuwertz}146_{, M. Kuze}156_{, J. Kvita}141_{, R. Kwee}15_, A. La Rosa49_{, L. La Rotonda}36a,36b_{, L. Labarga}79_{, J. Labbe}4_{, S. Lablak}134a_{, C. Lacasta}166_{, F. Lacava}131a,131b_, H. Lacker15_{, D. Lacour}77_{, V.R. Lacuesta}166_{, E. Ladygin}64_{, R. Lafaye}4_{, B. Laforge}77_{, T. Lagouri}79_{, S. Lai}48_, E. Laisne55_{, M. Lamanna}29_{, L. Lambourne}76_{, C.L. Lampen}6_{, W. Lampl}6_{, E. Lancon}135_{, U. Landgraf}48_,

M.P.J. Landon74_{, J.L. Lane}81_{, C. Lange}41_{, A.J. Lankford}162_{, F. Lanni}24_{, K. Lantzsch}173_{, S. Laplace}77_{, C. Lapoire}20_, J.F. Laporte135_{, T. Lari}88a_{, A.V. Larionov}127_{, A. Larner}117_{, C. Lasseur}29_{, M. Lassnig}29_{, P. Laurelli}47_,

V. Lavorini36a,36b_{, W. Lavrijsen}14_{, P. Laycock}72_{, A.B. Lazarev}64_{, O. Le Dortz}77_{, E. Le Guirriec}82_{, C. Le Maner}157_, E. Le Menedeu9_{, C. Lebel}92_{, T. LeCompte}5_{, F. Ledroit-Guillon}55_{, H. Lee}104_{, J.S.H. Lee}115_{, S.C. Lee}150_{, L. Lee}174_, M. Lefebvre168_{, M. Legendre}135_{, A. Leger}49_{, B.C. LeGeyt}119_{, F. Legger}97_{, C. Leggett}14_{, M. Lehmacher}20_,