Search For Higgs Boson Pair Production in the gamma gamma b bbar Final State using pp Collision Data at sqrt(s)=8 TeV from the ATLAS Detector

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Search For Higgs Boson Pair Production in the gamma

gamma b bbar Final State using pp Collision Data at

sqrt(s)=8 TeV from the ATLAS Detector

G. Aad, S. Albrand, J. Brown, J. Collot, S. Crépé-Renaudin, B. Dechenaux,

P.A. Delsart, C. Gabaldon, M.H. Genest, J.Y. Hostachy, et al.

To cite this version:

EUROPEAN ORGANISATION FOR NUCLEAR RESEARCH (CERN)

CERN-PH-EP-2014-113

Submitted to: PRL

Search for Higgs Boson Pair Production in the

γγb¯

b

Final State

using

pp

Collision Data at

√

s = 8 TeV

from the ATLAS

Detector

The ATLAS Collaboration

Abstract

Searches are performed for resonant and non-resonant Higgs boson pair production in the γγbb

final state using 20 fb

_{of proton–proton collisions at a center-of-mass energy of 8 TeV recorded with}

the ATLAS detector at the CERN Large Hadron Collider. A 95% confidence level upper limit on the

cross section times branching ratio of non-resonant production is set at 2.2 pb, while the expected

limit is 1.0 pb. The difference derives from a modest excess of events, corresponding to 2.4 standard

deviations from the background-only hypothesis. The limit observed in the search for a narrow X → hh

resonance ranges between 0.7 and 3.5 pb as a function of the resonance mass.

c

2015 CERN for the benefit of the ATLAS Collaboration.

Reproduction of this article or parts of it is allowed as specified in the CC-BY-3.0 license.

Search for Higgs Boson Pair Production in the γγb¯

b Final State

using pp Collision Data at

√

s = 8 TeV from the ATLAS Detector

Searches are performed for resonant and non-resonant Higgs boson pair production in the γγbb final state using 20 fb-1 _{of proton–proton collisions at a center-of-mass energy of 8 TeV recorded} with the ATLAS detector at the CERN Large Hadron Collider. A 95% confidence level upper limit on the cross section times branching ratio of non-resonant production is set at 2.2 pb, while the expected limit is 1.0 pb. The difference derives from a modest excess of events, corresponding to 2.4 standard deviations from the background-only hypothesis. The limit observed in the search for a narrow X → hh resonance ranges between 0.7 and 3.5 pb as a function of the resonance mass. PACS numbers: 12.60.Fr,14.80.Da,14.80.Ec

Within two years of discovering a new boson with a mass near 125 GeV [1, 2], the ATLAS and CMS collabo-rations have completed a slate of measurements demon-strating that its spin and couplings conform to the pre-dictions of the Standard Model (SM) Higgs boson within current experimental and theoretical uncertainties [3, 4]. Despite the lack of deviations from SM predictions, the Higgs boson, h, offers a rich potential for new physics searches. This Letter reports on searches for non-SM physics with events consistent with either resonant (X → hh) or non-resonant pair production of Higgs bosons in the hh → γγbb channel.

The predicted rate for Higgs boson pair production in the SM is several orders of magnitude smaller than the rate for the single h process [5–8]; hh production is thus not expected to be observable with current LHC data sets. However, a variety of extensions to the SM predict an enhancement of Higgs boson pair production. In two Higgs doublet models (2HDMs) [9–11] the heavier of the neutral scalar Higgs bosons, H, may decay to a pair of its lighter scalar partners, h. Depending on the parameters of the 2HDM, the H → hh production cross section may exceed a picobarn [11]. A deviation of the Higgs boson self-coupling, λhhh, from the SM predicted value could

also increase the non-resonant production rate. Such deviations could be observed with future data sets [8]. Larger enhancements in the pp → hh rate could arise from the top-Higgs quartic t¯thh coupling predicted in composite models [12, 13], or from the addition of light colored scalars to the SM [14]. Resonant production of two Higgs bosons could appear from the production and decay of gravitons, radions or stoponium [15–17], as well as from a hidden sector mixing with the observed Higgs boson [18].

The γγbb channel is an excellent final state for a search for Higgs boson pair production [19] thanks to the large h → bb branching ratio, clean diphoton trig-ger, excellent diphoton invariant mass resolution, and low backgrounds. This channel is particularly impor-tant in the search for resonances with mass, mX, in the

range 260 < mX < 500 GeV considered in this Letter,

where backgrounds and combinatorics make other chan-nels such as bbbb or b¯bτ+_τ− _challenging.

Processes that do not contain Higgs bosons are esti-mated from data; all other processes are simulated using

Monte Carlo techniques. The standard ATLAS detector simulation [20] based on Geant4 [21] is used. The simula-tion parameters are tuned to describe soft components of hadronic final states [22, 23]. Simulated minimum bias collisions are overlaid on the hard scatter process, and events are reweighted so that the average number of inter-actions per bunch crossing (∼20) matches the observed distribution.

Background events with a single Higgs boson produced in association with a W or Z boson or t¯t (W h, Zh, t¯_{th) are simulated with Pythia8 [24] using CTEQ6L1} parton distribution functions of the proton (PDFs) [25]. Higgs boson production via gluon or vector-boson fu-sion (ggF, VBF) is simulated using CT10 PDFs [26] with Powheg-Box [27, 28] interfaced to Pythia8 for showering and hadronization. Cross sections and associated uncer-tainties are taken from Ref. [29].

Two benchmark signal models are defined: SM Higgs boson pair production for the non-resonance search, and a gluon-initiated, spin-0 resonant state in the narrow-width approximation for the resonance search. The SM hh process is too small to observe with current data sets, but the SM kinematics are used to model generic non-resonant beyond-SM physics. Both models are gener-ated using MadGraph5 [30, 31] and CTEQ6L1 PDFs. A generator filter requires a pair of b-quarks and a pair of photons in each event. Pythia8 is used to decay the two Higgs bosons, and to shower and hadronize the events. The implementation of SM Higgs boson pair pro-duction includes the interference between diagrams with trilinear Higgs boson couplings and box diagrams. For the SM hh process, which is a background to the reso-nance search, the next-to-leading-order inclusive produc-tion cross secproduc-tion of 9.2 fb is taken from Ref. [8]. Reso-nant samples are generated with a width of 10 MeV (cor-responding to a narrow width approximation) at masses mX= 260, 300, 350, and 500 GeV. Production cross

sec-tions for benchmark 2HDM models are calculated with SusHi [32], and branching ratios with 2HDMC [33].

The analysis described in this Letter uses the full √

detector can be found elsewhere [37].

The photon and event selection for the present search largely follow those of published ATLAS h → γγ anal-yses [3, 38]. Events are selected using a loose diphoton trigger that is nearly 100% efficient for events passing the offline photon selection. Photons are reconstructed starting from clusters of energy deposited in the elec-tromagnetic calorimeter. Events are required to contain two photon candidates whose calorimeter energy clusters match the expectations for photon-induced electromag-netic showers [39, 40]. The pseudorapidity [41], η, of the two photons must fall within the geometric acceptance of the detector for photons, |η| < 2.37, excluding the region between the barrel and endcap calorimeters (1.37 < |η| < 1.56). The ratio of the transverse momentum of the lead-ing (subleadlead-ing) photon to the invariant mass of the pair, pT/mγγ, must exceed 0.35 (0.25). The invariant mass of

the pair is calculated as in Ref. [3]. Photons are required to be isolated: the energy in the calorimeter [3, 42] within a cone of size ∆R ≡p∆η2_{+ ∆φ}2_{= 0.4 around the}

pho-ton direction must be less than 6 GeV, and the scalar sum of the pTof the tracks in a cone of ∆R = 0.2 must be less

than 2.6 GeV. In addition, the photon pair must satisfy a broad requirement 105 < mγγ < 160 GeV for an event

to be considered [3, 38].

Jets are reconstructed from clusters of energy in the electromagnetic and hadronic calorimeters using the anti-kt algorithm [43] with a radius parameter of 0.4,

start-ing from energy deposits grouped into topological clus-ters [44]. Simulation is used to correct jets for instru-mental effects [45] and to account for the average energy in the detector in the event due to additional pp inter-actions and the underlying event [46]. The calibration is refined using in situ measurements. Jets are required to fall within the tracker acceptance of |η| < 2.5 and satisfy pT> 35 GeV, with the leading jet in the event required

to have pT> 55 GeV. Events with jets arising from noisy

regions in the calorimeters, beam backgrounds, or cos-mic rays are rejected [45]. Low-pT jets from additional

proton–proton interactions in the same bunch crossing are rejected with a requirement on the scalar sum of the pTof tracks associated with the jet: for jets with |η| < 2.4

and pT< 50 GeV, tracks associated with the hard scatter

vertex must contribute over 50% of the sum.

Jets from the decay of long-lived heavy-flavor hadrons are selected using a multivariate tagging algorithm (tagging) [47] with an efficiency of 70% for jets from b-quark fragmentation in t¯t simulation. The four-momenta of muons [48] closer than ∆R = 0.4 to a b-tagged jet and with pT> 4 GeV are included in the jet four-momentum.

Events with at least two photons and two or more jets are selected for further analysis if the invariant mass of the two leading jets is consistent with the decay of a Higgs boson. While the invariant mass resolution for the pairs of b-tagged jets is approximately 13 GeV, the mass window is chosen as 95 < mjj < 135 GeV to account

for the downward shift of the mean from the true value due to effects such as unmeasured neutrinos from

semi-leptonic b-decays.

In the non-resonance search, the background and po-tential signal are fit to the unbinned mγγ distribution

of all events passing the dijet and diphoton selections described above. This fit has three components: the sig-nal with a pair of Higgs bosons, the background pro-cesses with a single Higgs boson resonant at mγγ = mh,

and the continuum background. The single Higgs boson backgrounds are dominated by the processes with pairs of b-quarks, namely t¯th and (Z → b¯b)h, with smaller con-tributions from ggF, VBF, and W h. The combined ac-ceptance and selection efficiency for the SM Higgs boson pair production signal is 7.4%. Simulation studies show that the continuum contribution in the signal region is split between events with two photons and events with a single photon in association with a jet faking the second photon. The b-tagged jets include real heavy-flavor jets and mis-tagged light-flavor jets. The contribution from dileptonic decays of t¯t events where two electrons fake the two photons is roughly 10% of the total background. The contribution from other processes is negligible.

The fit is performed simultaneously in two categories. The first category is the signal region, in which at least two jets are b-tagged. The second is a control region, containing events with fewer than two b-tags. The two classes of events are kinematically identical: in the signal region, the mass and pTrequirements defined above must

be satisfied by the two leading tagged jets, whereas in the control region, they are met by the two leading jets.

Following earlier ATLAS analyses, the shape of the mγγ resonance is described by the sum of a Crystal Ball

function and a wide Gaussian component that models the tails of the distribution [3]. An exponential func-tion describes the continuum backgrounds that fall with mγγ. The slope of the exponential is shared in the fit

be-tween the two categories so that the control region con-strains the background shape in the signal region. Fig-ure 1 shows the separate diphoton mass distributions for events with ≥ 2 b-tags and events with ≤ 1 b-tag.

The search for resonant production of pairs of Higgs bosons starts with the same signal selection as above but imposes an additional requirement on m_γγbb. Due to the small number of expected events after this addi-tional requirement, the resonance analysis uses a count-ing experiment with cuts on mγγand mγγbb, in place of

the unbinned fit in mγγ. The cut on the diphoton mass

is set as a window of twice the mass resolution, ±2σmγγ,

around the Higgs boson mass, mh = 125.5 GeV [3]. For

this cut, the mγγ resolution is set to the expected value

of 1.6 GeV. The acceptance of this requirement on back-ground events without Higgs bosons, mγγ, is measured

by fitting an exponential function to the mγγ sidebands

for events with fewer than two b-tagged jets. For this fit, the mγγ region of mh± 5 GeV is excluded to

elim-inate any potential contamination from resonant Higgs boson production. For N observed events with two b-tags in the sideband (|mγγ− mh| > 2σmγγ), the number

[GeV] γ γ m 110 120 130 140 150 160 Events / 2.5 GeV ₀ 20 40 60 80 100

< 2 b-Tag Control Region

[GeV] γ γ m Events / 2.5 GeV 0 2 4 6 8 10 Signal Region Data Fitted Signal + Bkds Single Higgs Boson + Bkd Continuum Background

ATLAS

∫

FIG. 1. (Upper plot) Diphoton invariant mass spectrum for data and the corresponding fitted signal and background in the signal region for the non-resonance search. (Lower plot) The diphoton invariant mass spectrum in the continuum background from events with fewer than two b-tags and the corresponding fitted curve, the shape of which is also used in the upper plot.

within 2σmγγ around mhis given by:

Nmγγ= N

mγγ

1 − mγγ

, (1)

where the denominator compensates for the fact that mγγ = 0.13 is derived relative to the full mγγ spectrum

while N contains only those events in the sidebands. Before reconstructing the four-object mass, m_γγbb, a scaling factor of mh/mbb is applied to the

four-momentum of the b¯b system, where mhis set to the value

of 125 GeV used in simulation. This improves the m_γγbb resolution by 30–60% depending on the mass hypothe-sis, without biasing or significantly altering the shape of the background. Requirements are then made on m_γγbb to select the smallest window containing 95% of the previously-selected events, simulated for the narrow resonant signal hypotheses. These requirements vary lin-early with the mass, mX, of the resonance considered.

The width of the signal window varies from 17 GeV at mX = 260 GeV to 60 GeV at mX = 500 GeV. The

ac-ceptance for the continuum background to pass this re-quirement, m_γγbb, also varies with mX. It is measured

using events in data with |mγγ− mh| < 2σmγγ and fewer

than two b-tags. Studies in both data sidebands and simulation show that the shapes of m_γγbb and mγγjj

agree within statistical uncertainties. The distribution of mγγjj in data is fitted with a Landau function, which

is integrated in the signal window to obtain m_γγbb for

each mass hypothesis. The bottom panel of Fig. 2 shows this fit. The value of m_γγbb is small (< 8%) at low and

high mX, and peaks at 18% for mX = 300 GeV. The

[GeV] bb γ γ Constrained m Events / 5 GeV -2 10 -1 10 1 10 Signal Region Data

Control Region Fit Single Higgs Boson

=1 pb hh BR × X σ =300 GeV, X m ATLAS

∫

< 2 b-Tag Control Region Data Landau Fit

FIG. 2. (Upper plot) The constrained four-object invari-ant mass, mγγjj, for data events in the resonance signal re-gion. The expected backgrounds are also shown. A narrow width resonance at 300 GeV is displayed for comparison only. (Lower plot) The diphoton invariant mass spectrum in the continuum background from events with fewer than two b-tags and the corresponding fitted curve, the shape of which is also used in the upper plot.

combined acceptance and selection efficiency for a reso-nance signal to pass all requirements varies from 3.8% at mX= 260 GeV to 8.2% at mX= 500 GeV.

The total background from sources without Higgs bo-son decays in the rebo-sonance analysis NB is given by:

NB= N

mγγ

1 − mγγ

m_γγbb, (2)

where N is the number of events in the mγγ sidebands,

and NB and m_γγbb are functions of mX. Uncertainties

on this extrapolation are described below.

Because they are not accounted for by the above mγγsideband techniques, contributions from single Higgs

bosons produced in association with jets (particularly with c¯c or b¯b pairs) are estimated using simulation. In the resonance analysis, the yield from the non-resonant SM hh processes is similarly included. SM cross sections and branching fractions are assumed in all cases [29].

Most systematic uncertainties are small when com-pared to statistical uncertainties, in particular for the resonance search.

sim-ulated predictions to data for similar initial states: gluon-initiated production of t¯t with heavy flavor [49] for ggF, and quark-initiated W boson production with heavy fla-vor [50] for VBF. Since the ggF and VBF contributions are less than 15% of the expected single Higgs boson yield in the signal region, the net impact of these uncertainties remains small. PDF and scale uncertainties on SM hh production are taken from Ref. [8].

Because of the cuts on the ratio pT/mγγ, photon

en-ergy scale uncertainties are negligible. The uncertainty of 13% on the diphoton mass resolution σmγγ is

propa-gated into the resonance search as a 1.6% uncertainty on the number of events migrating into and out of the sig-nal region. This represents the fraction of events where an upward variation of the photon resolution causes the diphoton mass to leave the mh± 2σmγγ window required

for the signal region. The uncertainty on mhimpacts the

peak position in mγγ in the signal plus background fit of

the non-resonance analysis, and in the resonance search it is transformed into a 1.7% uncertainty on the number of signal events in the mass window. The uncertainty for the acceptance of the mγγ cuts on non-Higgs boson

backgrounds is estimated by comparing fits of mγγ to

data in control regions with reversed photon identifica-tion or b-tagging requirements, and using different func-tional forms. The largest deviation observed from these fits (11%) is used for all searches.

Three components contribute to the uncertainty on m_γγbb, and are combined in quadrature. (1) The

lim-ited number of events in the control region with fewer than two b-tags used for the Landau fit lead to a relative statistical uncertainty of 3–18% that varies as a function of mX. (2) The mγγjj shape for untagged jets might not

exactly mirror the one for tagged jets. The tagged and untagged samples are compared in simulation and the rel-ative difference in m_γγbbis taken as the uncertainty. This

value varies with mX and is always less than 30%. (3)

Finally, an uncertainty of 16–30%, depending on mX, is

included to cover the choice of the analytic function. This was evaluated via comparisons of Landau shapes to al-ternate functions in simulation, including Landau shapes where the width varies with m_γγbb, as well as Crystal Ball functions. Potential contamination from SM single Higgs boson processes in the control region is estimated to be less than 4% and is subtracted with negligible impact on the shape.

Uncertainties due to the b-tagging calibration are typ-ically 2–4% for both the single Higgs boson and signal processes. Uncertainties due to the jet energy scale are 7% (22%) for single Higgs boson backgrounds in the non-resonance (resonant) analysis, and 1.4% (4.4%) for signal processes. Uncertainties due to the jet energy resolution are 4.8% (21%) for single Higgs boson backgrounds, and 6.3% (9.3%) for signal processes. The uncertainty on the integrated luminosity is 2.8%. It is derived, follow-ing the same methodology as that detailed in Ref. [34], from a preliminary calibration of the luminosity scale de-rived from beam-separation scans performed in

Novem-ber 2012.

The combined, unbinned signal plus background fit for the non-resonance analysis is shown in Fig. 1. Within a ±2σmγγ window around the Higgs boson mass, 1.5

events are expected, with 1.3 ± 0.5 from the contin-uum background and 0.17 ± 0.04 from single Higgs boson production, which is dominated by t¯th events. About 0.04 events are expected from SM Higgs boson pair pro-duction. Five events are observed, corresponding to 2.4σ from the background-only hypothesis, using the test statistic based on the profile likelihood ratio [51] with the hypothesized signal rate set to zero. The 95% confidence level (CL) upper limit on the Higgs boson pair produc-tion cross secproduc-tion is calculated using the frequentist CLS

method [52]. Exclusions and significances are evaluated using pseudo-experiments. Assuming SM branching ra-tios for the light Higgs boson decays, the expected upper limit is 1.0+0.5_−0.2 pb; the observed limit is 2.2 pb.

For the resonance analysis, as before, SM branching fractions for the light Higgs boson are assumed. The ex-pected exclusion improves from 1.7 to 0.7 pb as a func-tion of mXfrom 260 to 500 GeV, as shown in Fig. 3. This

behavior derives from increased event-level acceptance at larger masses. The observed exclusion ranges from 3.5 to 0.7 pb. The five events selected in the mγγ signal

re-gion are shown in m_γγbb, in Fig. 2. The local probability of compatibility to the background-only hypothesis, p0,

reaches a minimum of 0.002 at mX = 300 GeV,

corre-sponding to 3.0σ. The number of events lying within the m_γγbb window of each mass hypothesis is readily ap-parent in ‘steps’ in the exclusion plot. The step size used for the limit is reduced in the range near the ob-served events, to show this structure. A look-elsewhere effect [53, 54] is evaluated by generating pseudo-datasets of the background-only hypothesis, and identifying the mass hypothesis with the lowest p-value in each. The global probability of an exccess as significant as the ob-servation to occur at any mass in the range studied is found to be 0.019, corresponding to 2.1σ.

The limits derived are juxtaposed in Fig. 3 with the prediction for an illustrative type I 2HDM [32, 33, 55] not excluded by current data with cos(β − α) = −0.05 and tan(β) = 1. The heavy Higgs bosons are taken to be degenerate in mass, and the mass of the lightest CP-even Higgs boson is set to 125 GeV. All major produc-tion mechanisms of H → hh are considered. Cross sec-tions and branching ratios were calculated as described in Ref. [56].

In conclusion, this Letter presents searches for reso-nant and non-resoreso-nant Higgs boson pair production using 20.3 fb-1 of proton–proton collision data at √s = 8 TeV generated by the Large Hadron Collider and recorded by the ATLAS detector in 2012. A 95% confidence level up-per limit is placed on the non-resonant production cross section at 2.2 pb, while the expected limit is 1.0+0.5_−0.2pb. The difference derives from a small excess of events, cor-responding to 2.4σ.

[GeV] X m 300 350 400 450 500 hh) [pb] → BR(X × X σ 0.5 1 1.5 2 2.5 3 3.5 4 4.5 ATLAS ∫Ldt = 20 fb-1 at s = 8 TeV Observed 95% CL Limit σ 1 ± Expected Limit σ 2 ± Expected Limit Type I 2HDM: )=-0.05 α -β =1, cos( β tan

FIG. 3. A 95% CL upper limit on the cross section times branching ratio of a narrow resonance decaying to pairs of Higgs bosons as a function of mX (see text for more details).

of Higgs bosons, the expected exclusion on the produc-tion cross secproduc-tion falls from 1.7 pb for a resonance at 260 GeV to 0.7 pb at 500 GeV. The observed exclusion ranges from 0.7–3.5 pb. It is weaker than expected for resonances below 350 GeV.

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; BMWFW and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq

and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT and NSRF, Greece; ISF, MINERVA, GIF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT, Portugal; MNE/IFA, Romania; MES of Russia and ROSATOM, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MIZˇS, Slove-nia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Tai-wan; TAEK, Turkey; STFC, the Royal Society and Lev-erhulme 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.

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The ATLAS Collaboration

G. Aad84, B. Abbott112, J. Abdallah152, S. Abdel Khalek116, O. Abdinov11, R. Aben106, B. Abi113, M. Abolins89, O.S. AbouZeid159_{, H. Abramowicz}154_{, H. Abreu}153_{, R. Abreu}30_{, Y. Abulaiti}147a,147b_{, B.S. Acharya}165a,165b,a_,

L. Adamczyk38a_{, D.L. Adams}25_{, J. Adelman}177_{, S. Adomeit}99_{, T. Adye}130_{, T. Agatonovic-Jovin}13a_,

J.A. Aguilar-Saavedra125a,125f_{, M. Agustoni}17_{, S.P. Ahlen}22_{, F. Ahmadov}64,b_{, G. Aielli}134a,134b_,

H. Akerstedt147a,147b_{, T.P.A. ˚Akesson}80_{, G. Akimoto}156_{, A.V. Akimov}95_{, G.L. Alberghi}20a,20b_{, J. Albert}170_,

S. Albrand55, M.J. Alconada Verzini70, M. Aleksa30, I.N. Aleksandrov64, C. Alexa26a, G. Alexander154,

G. Alexandre49, T. Alexopoulos10, M. Alhroob165a,165c, G. Alimonti90a, L. Alio84, J. Alison31, B.M.M. Allbrooke18, L.J. Allison71_{, P.P. Allport}73_{, J. Almond}83_{, A. Aloisio}103a,103b_{, A. Alonso}36_{, F. Alonso}70_{, C. Alpigiani}75_,

A. Altheimer35_{, B. Alvarez Gonzalez}89_{, M.G. Alviggi}103a,103b_{, K. Amako}65_{, Y. Amaral Coutinho}24a_{, C. Amelung}23_,

D. Amidei88_{, S.P. Amor Dos Santos}125a,125c_{, A. Amorim}125a,125b_{, S. Amoroso}48_{, N. Amram}154_{, G. Amundsen}23_,

C. Anastopoulos140, L.S. Ancu49, N. Andari30, T. Andeen35, C.F. Anders58b, G. Anders30, K.J. Anderson31, A. Andreazza90a,90b, V. Andrei58a, X.S. Anduaga70, S. Angelidakis9, I. Angelozzi106, P. Anger44, A. Angerami35, F. Anghinolfi30_{, A.V. Anisenkov}108_{, N. Anjos}125a_{, A. Annovi}47_{, A. Antonaki}9_{, M. Antonelli}47_{, A. Antonov}97_,

J. Antos145b_{, F. Anulli}133a_{, M. Aoki}65_{, L. Aperio Bella}18_{, R. Apolle}119,c_{, G. Arabidze}89_{, I. Aracena}144_{, Y. Arai}65_,

J.P. Araque125a_{, A.T.H. Arce}45_{, J-F. Arguin}94_{, S. Argyropoulos}42_{, M. Arik}19a_{, A.J. Armbruster}30_{, O. Arnaez}30_,

V. Arnal81_{, H. Arnold}48_{, M. Arratia}28_{, O. Arslan}21_{, A. Artamonov}96_{, G. Artoni}23_{, S. Asai}156_{, N. Asbah}42_,

A. Ashkenazi154, B. ˚Asman147a,147b, L. Asquith6, K. Assamagan25, R. Astalos145a, M. Atkinson166, N.B. Atlay142, B. Auerbach6_{, K. Augsten}127_{, M. Aurousseau}146b_{, G. Avolio}30_{, G. Azuelos}94,d_{, Y. Azuma}156_{, M.A. Baak}30_,

A. Baas58a_{, C. Bacci}135a,135b_{, H. Bachacou}137_{, K. Bachas}155_{, M. Backes}30_{, M. Backhaus}30_{, J. Backus Mayes}144_,

E. Badescu26a_{, P. Bagiacchi}133a,133b_{, P. Bagnaia}133a,133b_{, Y. Bai}33a_{, T. Bain}35_{, J.T. Baines}130_{, O.K. Baker}177_,

P. Balek128_{, F. Balli}137_{, E. Banas}39_{, Sw. Banerjee}174_{, A.A.E. Bannoura}176_{, V. Bansal}170_{, H.S. Bansil}18_{, L. Barak}173_,

S.P. Baranov95, E.L. Barberio87, D. Barberis50a,50b, M. Barbero84, T. Barillari100, M. Barisonzi176, T. Barklow144, N. Barlow28, B.M. Barnett130, R.M. Barnett15, Z. Barnovska5, A. Baroncelli135a, G. Barone49, A.J. Barr119, F. Barreiro81_{, J. Barreiro Guimar˜aes da Costa}57_{, R. Bartoldus}144_{, A.E. Barton}71_{, P. Bartos}145a_{, V. Bartsch}150_,

A. Bassalat116_{, A. Basye}166_{, R.L. Bates}53_{, L. Batkova}145a_{, J.R. Batley}28_{, M. Battaglia}138_{, M. Battistin}30_,

F. Bauer137_{, H.S. Bawa}144,e_{, T. Beau}79_{, P.H. Beauchemin}162_{, R. Beccherle}123a,123b_{, P. Bechtle}21_{, H.P. Beck}17_,

K. Becker176_{, S. Becker}99_{, M. Beckingham}171_{, C. Becot}116_{, A.J. Beddall}19c_{, A. Beddall}19c_{, S. Bedikian}177_,

V.A. Bednyakov64, C.P. Bee149, L.J. Beemster106, T.A. Beermann176, M. Begel25, K. Behr119,

C. Belanger-Champagne86_{, P.J. Bell}49_{, W.H. Bell}49_{, G. Bella}154_{, L. Bellagamba}20a_{, A. Bellerive}29_{, M. Bellomo}85_,

K. Belotskiy97_{, O. Beltramello}30_{, O. Benary}154_{, D. Benchekroun}136a_{, K. Bendtz}147a,147b_{, N. Benekos}166_,

Y. Benhammou154_{, E. Benhar Noccioli}49_{, J.A. Benitez Garcia}160b_{, D.P. Benjamin}45_{, J.R. Bensinger}23_,

K. Benslama131_{, S. Bentvelsen}106_{, D. Berge}106_{, E. Bergeaas Kuutmann}16_{, N. Berger}5_{, F. Berghaus}170_{, J. Beringer}15_,

C. Bernard22, P. Bernat77, C. Bernius78, F.U. Bernlochner170, T. Berry76, P. Berta128, C. Bertella84,

G. Bertoli147a,147b, F. Bertolucci123a,123b, D. Bertsche112, M.I. Besana90a, G.J. Besjes105, O. Bessidskaia147a,147b, M.F. Bessner42_{, N. Besson}137_{, C. Betancourt}48_{, S. Bethke}100_{, W. Bhimji}46_{, R.M. Bianchi}124_{, L. Bianchini}23_,

M. Bianco30_{, O. Biebel}99_{, S.P. Bieniek}77_{, K. Bierwagen}54_{, J. Biesiada}15_{, M. Biglietti}135a_{, J. Bilbao De Mendizabal}49_,

H. Bilokon47_{, M. Bindi}54_{, S. Binet}116_{, A. Bingul}19c_{, C. Bini}133a,133b_{, C.W. Black}151_{, J.E. Black}144_{, K.M. Black}22_,

D. Blackburn139, R.E. Blair6, J.-B. Blanchard137, T. Blazek145a, I. Bloch42, C. Blocker23, W. Blum82,∗,

U. Blumenschein54, G.J. Bobbink106, V.S. Bobrovnikov108, S.S. Bocchetta80, A. Bocci45, C. Bock99, C.R. Boddy119, M. Boehler48_{, T.T. Boek}176_{, J.A. Bogaerts}30_{, A.G. Bogdanchikov}108_{, A. Bogouch}91,∗_{, C. Bohm}147a_{, J. Bohm}126_,

V. Boisvert76_{, T. Bold}38a_{, V. Boldea}26a_{, A.S. Boldyrev}98_{, M. Bomben}79_{, M. Bona}75_{, M. Boonekamp}137_,

A. Borisov129_{, G. Borissov}71_{, M. Borri}83_{, S. Borroni}42_{, J. Bortfeldt}99_{, V. Bortolotto}135a,135b_{, K. Bos}106_,

D. Boscherini20a_{, M. Bosman}12_{, H. Boterenbrood}106_{, J. Boudreau}124_{, J. Bouffard}2_{, E.V. Bouhova-Thacker}71_,

D. Boumediene34, C. Bourdarios116, N. Bousson113, S. Boutouil136d, A. Boveia31, J. Boyd30, I.R. Boyko64, J. Bracinik18_{, A. Brandt}8_{, G. Brandt}15_{, O. Brandt}58a_{, U. Bratzler}157_{, B. Brau}85_{, J.E. Brau}115_{, H.M. Braun}176,∗_,

S.F. Brazzale165a,165c_{, B. Brelier}159_{, K. Brendlinger}121_{, A.J. Brennan}87_{, R. Brenner}167_{, S. Bressler}173_,

K. Bristow146c_{, T.M. Bristow}46_{, D. Britton}53_{, F.M. Brochu}28_{, I. Brock}21_{, R. Brock}89_{, C. Bromberg}89_{, J. Bronner}100_,

G. Brooijmans35_{, T. Brooks}76_{, W.K. Brooks}32b_{, J. Brosamer}15_{, E. Brost}115_{, J. Brown}55_,

P.A. Bruckman de Renstrom39, D. Bruncko145b, R. Bruneliere48, S. Brunet60, A. Bruni20a, G. Bruni20a, M. Bruschi20a, L. Bryngemark80, T. Buanes14, Q. Buat143, F. Bucci49, P. Buchholz142, R.M. Buckingham119, A.G. Buckley53_{, S.I. Buda}26a_{, I.A. Budagov}64_{, F. Buehrer}48_{, L. Bugge}118_{, M.K. Bugge}118_{, O. Bulekov}97_,

A.C. Bundock73_{, H. Burckhart}30_{, S. Burdin}73_{, B. Burghgrave}107_{, S. Burke}130_{, I. Burmeister}43_{, E. Busato}34_,

D. B¨uscher48_{, V. B¨uscher}82_{, P. Bussey}53_{, C.P. Buszello}167_{, B. Butler}57_{, J.M. Butler}22_{, A.I. Butt}3_{, C.M. Buttar}53_,

J.M. Butterworth77_{, P. Butti}106_{, W. Buttinger}28_{, A. Buzatu}53_{, M. Byszewski}10_{, S. Cabrera Urb´an}168_,

R. Caminal Armadans12, S. Campana30, M. Campanelli77, A. Campoverde149, V. Canale103a,103b, A. Canepa160a, M. Cano Bret75, J. Cantero81, R. Cantrill76, T. Cao40, M.D.M. Capeans Garrido30, I. Caprini26a, M. Caprini26a, M. Capua37a,37b_{, R. Caputo}82_{, R. Cardarelli}134a_{, T. Carli}30_{, G. Carlino}103a_{, L. Carminati}90a,90b_{, S. Caron}105_,

E. Carquin32a_{, G.D. Carrillo-Montoya}146c_{, J.R. Carter}28_{, J. Carvalho}125a,125c_{, D. Casadei}77_{, M.P. Casado}12_,

M. Casolino12_{, E. Castaneda-Miranda}146b_{, A. Castelli}106_{, V. Castillo Gimenez}168_{, N.F. Castro}125a_{, P. Catastini}57_,

A. Catinaccio30, J.R. Catmore118, A. Cattai30, G. Cattani134a,134b, S. Caughron89, V. Cavaliere166, D. Cavalli90a, M. Cavalli-Sforza12, V. Cavasinni123a,123b, F. Ceradini135a,135b, B. Cerio45, K. Cerny128, A.S. Cerqueira24b, A. Cerri150_{, L. Cerrito}75_{, F. Cerutti}15_{, M. Cerv}30_{, A. Cervelli}17_{, S.A. Cetin}19b_{, A. Chafaq}136a_{, D. Chakraborty}107_,

I. Chalupkova128_{, P. Chang}166_{, B. Chapleau}86_{, J.D. Chapman}28_{, D. Charfeddine}116_{, D.G. Charlton}18_{, C.C. Chau}159_,

C.A. Chavez Barajas150_{, S. Cheatham}86_{, A. Chegwidden}89_{, S. Chekanov}6_{, S.V. Chekulaev}160a_{, G.A. Chelkov}64,f_,

M.A. Chelstowska88_{, C. Chen}63_{, H. Chen}25_{, K. Chen}149_{, L. Chen}33d,g_{, S. Chen}33c_{, X. Chen}146c_{, Y. Chen}35_,

H.C. Cheng88, Y. Cheng31, A. Cheplakov64, R. Cherkaoui El Moursli136e, V. Chernyatin25,∗, E. Cheu7, L. Chevalier137, V. Chiarella47, G. Chiefari103a,103b, J.T. Childers6, A. Chilingarov71, G. Chiodini72a, A.S. Chisholm18_{, R.T. Chislett}77_{, A. Chitan}26a_{, M.V. Chizhov}64_{, S. Chouridou}9_{, B.K.B. Chow}99_,

D. Chromek-Burckhart30_{, M.L. Chu}152_{, J. Chudoba}126_{, J.J. Chwastowski}39_{, L. Chytka}114_{, G. Ciapetti}133a,133b_,

A.K. Ciftci4a_{, R. Ciftci}4a_{, D. Cinca}53_{, V. Cindro}74_{, A. Ciocio}15_{, P. Cirkovic}13b_{, Z.H. Citron}173_{, M. Citterio}90a_,

M. Ciubancan26a, A. Clark49, P.J. Clark46, R.N. Clarke15, W. Cleland124, J.C. Clemens84, C. Clement147a,147b, Y. Coadou84, M. Cobal165a,165c, A. Coccaro139, J. Cochran63, L. Coffey23, J.G. Cogan144, J. Coggeshall166, B. Cole35_{, S. Cole}107_{, A.P. Colijn}106_{, J. Collot}55_{, T. Colombo}58c_{, G. Colon}85_{, G. Compostella}100_,

P. Conde Mui˜no125a,125b_{, E. Coniavitis}48_{, M.C. Conidi}12_{, S.H. Connell}146b_{, I.A. Connelly}76_{, S.M. Consonni}90a,90b_,

V. Consorti48_{, S. Constantinescu}26a_{, C. Conta}120a,120b_{, G. Conti}57_{, F. Conventi}103a,h_{, M. Cooke}15_{, B.D. Cooper}77_,

A.M. Cooper-Sarkar119_{, N.J. Cooper-Smith}76_{, K. Copic}15_{, T. Cornelissen}176_{, M. Corradi}20a_{, F. Corriveau}86,i_,

A. Corso-Radu164, A. Cortes-Gonzalez12, G. Cortiana100, G. Costa90a, M.J. Costa168, D. Costanzo140, D. Cˆot´e8, G. Cottin28_{, G. Cowan}76_{, B.E. Cox}83_{, K. Cranmer}109_{, G. Cree}29_{, S. Cr´ep´e-Renaudin}55_{, F. Crescioli}79_,

W.A. Cribbs147a,147b_{, M. Crispin Ortuzar}119_{, M. Cristinziani}21_{, V. Croft}105_{, G. Crosetti}37a,37b_{, C.-M. Cuciuc}26a_,

T. Cuhadar Donszelmann140_{, J. Cummings}177_{, M. Curatolo}47_{, C. Cuthbert}151_{, H. Czirr}142_{, P. Czodrowski}3_,

Z. Czyczula177_{, S. D’Auria}53_{, M. D’Onofrio}73_{, M.J. Da Cunha Sargedas De Sousa}125a,125b_{, C. Da Via}83_,

W. Dabrowski38a, A. Dafinca119, T. Dai88, O. Dale14, F. Dallaire94, C. Dallapiccola85, M. Dam36, A.C. Daniells18, M. Dano Hoffmann137, V. Dao105, G. Darbo50a, S. Darmora8, J.A. Dassoulas42, A. Dattagupta60, W. Davey21, C. David170_{, T. Davidek}128_{, E. Davies}119,c_{, M. Davies}154_{, O. Davignon}79_{, A.R. Davison}77_{, P. Davison}77_,

Y. Davygora58a_{, E. Dawe}143_{, I. Dawson}140_{, R.K. Daya-Ishmukhametova}85_{, K. De}8_{, R. de Asmundis}103a_,

S. De Castro20a,20b_{, S. De Cecco}79_{, N. De Groot}105_{, P. de Jong}106_{, H. De la Torre}81_{, F. De Lorenzi}63_,

L. De Nooij106, D. De Pedis133a, A. De Salvo133a, U. De Sanctis165a,165b, A. De Santo150, J.B. De Vivie De Regie116, W.J. Dearnaley71, R. Debbe25, C. Debenedetti138, B. Dechenaux55, D.V. Dedovich64, I. Deigaard106, J. Del Peso81, T. Del Prete123a,123b_{, F. Deliot}137_{, C.M. Delitzsch}49_{, M. Deliyergiyev}74_{, A. Dell’Acqua}30_{, L. Dell’Asta}22_,

M. Dell’Orso123a,123b_{, M. Della Pietra}103a,h_{, D. della Volpe}49_{, M. Delmastro}5_{, P.A. Delsart}55_{, C. Deluca}106_,

S. Demers177_{, M. Demichev}64_{, A. Demilly}79_{, S.P. Denisov}129_{, D. Derendarz}39_{, J.E. Derkaoui}136d_{, F. Derue}79_,

P. Dervan73_{, K. Desch}21_{, C. Deterre}42_{, P.O. Deviveiros}106_{, A. Dewhurst}130_{, S. Dhaliwal}106_{, A. Di Ciaccio}134a,134b_,

L. Di Ciaccio5, A. Di Domenico133a,133b, C. Di Donato103a,103b, A. Di Girolamo30, B. Di Girolamo30, A. Di Mattia153, B. Di Micco135a,135b, R. Di Nardo47, A. Di Simone48, R. Di Sipio20a,20b, D. Di Valentino29, F.A. Dias46_{, M.A. Diaz}32a_{, E.B. Diehl}88_{, J. Dietrich}42_{, T.A. Dietzsch}58a_{, S. Diglio}84_{, A. Dimitrievska}13a_,

J. Dingfelder21_{, C. Dionisi}133a,133b_{, P. Dita}26a_{, S. Dita}26a_{, F. Dittus}30_{, F. Djama}84_{, T. Djobava}51b_,

M.A.B. do Vale24c_{, A. Do Valle Wemans}125a,125g_{, T.K.O. Doan}5_{, D. Dobos}30_{, C. Doglioni}49_{, T. Doherty}53_,

T. Dohmae156, J. Dolejsi128, Z. Dolezal128, B.A. Dolgoshein97,∗, M. Donadelli24d, S. Donati123a,123b,

P. Dondero120a,120b, J. Donini34, J. Dopke130, A. Doria103a, M.T. Dova70, A.T. Doyle53, M. Dris10, J. Dubbert88, S. Dube15_{, E. Dubreuil}34_{, E. Duchovni}173_{, G. Duckeck}99_{, O.A. Ducu}26a_{, D. Duda}176_{, A. Dudarev}30_{, F. Dudziak}63_,

L. Duflot116_{, L. Duguid}76_{, M. D¨uhrssen}30_{, M. Dunford}58a_{, H. Duran Yildiz}4a_{, M. D¨uren}52_{, A. Durglishvili}51b_,

M. Dwuznik38a_{, M. Dyndal}38a_{, J. Ebke}99_{, W. Edson}2_{, N.C. Edwards}46_{, W. Ehrenfeld}21_{, T. Eifert}144_{, G. Eigen}14_,

K. Einsweiler15_{, T. Ekelof}167_{, M. El Kacimi}136c_{, M. Ellert}167_{, S. Elles}5_{, F. Ellinghaus}82_{, N. Ellis}30_{, J. Elmsheuser}99_,

M. Elsing30, D. Emeliyanov130, Y. Enari156, O.C. Endner82, M. Endo117, R. Engelmann149, J. Erdmann177, A. Ereditato17_{, D. Eriksson}147a_{, G. Ernis}176_{, J. Ernst}2_{, M. Ernst}25_{, J. Ernwein}137_{, D. Errede}166_{, S. Errede}166_,

E. Ertel82_{, M. Escalier}116_{, H. Esch}43_{, C. Escobar}124_{, B. Esposito}47_{, A.I. Etienvre}137_{, E. Etzion}154_{, H. Evans}60_,

A. Ezhilov122_{, L. Fabbri}20a,20b_{, G. Facini}31_{, R.M. Fakhrutdinov}129_{, S. Falciano}133a_{, R.J. Falla}77_{, J. Faltova}128_,

Y. Fang33a_{, M. Fanti}90a,90b_{, A. Farbin}8_{, A. Farilla}135a_{, T. Farooque}12_{, S. Farrell}164_{, S.M. Farrington}171_,

P. Farthouat30, F. Fassi168, P. Fassnacht30, D. Fassouliotis9, A. Favareto50a,50b, L. Fayard116, P. Federic145a, O.L. Fedin122,j, W. Fedorko169, M. Fehling-Kaschek48, S. Feigl30, L. Feligioni84, C. Feng33d, E.J. Feng6, H. Feng88, A.B. Fenyuk129_{, S. Fernandez Perez}30_{, S. Ferrag}53_{, J. Ferrando}53_{, A. Ferrari}167_{, P. Ferrari}106_{, R. Ferrari}120a_,

F. Fiedler82, A. Filipˇciˇc74, M. Filipuzzi42, F. Filthaut105, M. Fincke-Keeler170, K.D. Finelli151,

M.C.N. Fiolhais125a,125c, L. Fiorini168, A. Firan40, A. Fischer2, J. Fischer176, W.C. Fisher89, E.A. Fitzgerald23, M. Flechl48_{, I. Fleck}142_{, P. Fleischmann}88_{, S. Fleischmann}176_{, G.T. Fletcher}140_{, G. Fletcher}75_{, T. Flick}176_,

A. Floderus80_{, L.R. Flores Castillo}174,k_{, A.C. Florez Bustos}160b_{, M.J. Flowerdew}100_{, A. Formica}137_{, A. Forti}83_,

D. Fortin160a_{, D. Fournier}116_{, H. Fox}71_{, S. Fracchia}12_{, P. Francavilla}79_{, M. Franchini}20a,20b_{, S. Franchino}30_,

D. Francis30, M. Franklin57, S. Franz61, M. Fraternali120a,120b, S.T. French28, C. Friedrich42, F. Friedrich44, D. Froidevaux30, J.A. Frost28, C. Fukunaga157, E. Fullana Torregrosa82, B.G. Fulsom144, J. Fuster168, C. Gabaldon55_{, O. Gabizon}173_{, A. Gabrielli}20a,20b_{, A. Gabrielli}133a,133b_{, S. Gadatsch}106_{, S. Gadomski}49_,

G. Gagliardi50a,50b_{, P. Gagnon}60_{, C. Galea}105_{, B. Galhardo}125a,125c_{, E.J. Gallas}119_{, V. Gallo}17_{, B.J. Gallop}130_,

P. Gallus127_{, G. Galster}36_{, K.K. Gan}110_{, R.P. Gandrajula}62_{, J. Gao}33b,g_{, Y.S. Gao}144,e_{, F.M. Garay Walls}46_,

F. Garberson177_{, C. Garc´ıa}168_{, J.E. Garc´ıa Navarro}168_{, M. Garcia-Sciveres}15_{, R.W. Gardner}31_{, N. Garelli}144_,

V. Garonne30, C. Gatti47, G. Gaudio120a, B. Gaur142, L. Gauthier94, P. Gauzzi133a,133b, I.L. Gavrilenko95, C. Gay169, G. Gaycken21, E.N. Gazis10, P. Ge33d, Z. Gecse169, C.N.P. Gee130, D.A.A. Geerts106,

Ch. Geich-Gimbel21_{, K. Gellerstedt}147a,147b_{, C. Gemme}50a_{, A. Gemmell}53_{, M.H. Genest}55_{, S. Gentile}133a,133b_,

M. George54_{, S. George}76_{, D. Gerbaudo}164_{, A. Gershon}154_{, H. Ghazlane}136b_{, N. Ghodbane}34_{, B. Giacobbe}20a_,

S. Giagu133a,133b_{, V. Giangiobbe}12_{, P. Giannetti}123a,123b_{, F. Gianotti}30_{, B. Gibbard}25_{, S.M. Gibson}76_,

M. Gilchriese15, T.P.S. Gillam28, D. Gillberg30, G. Gilles34, D.M. Gingrich3,d, N. Giokaris9, M.P. Giordani165a,165c, R. Giordano103a,103b, F.M. Giorgi20a, F.M. Giorgi16, P.F. Giraud137, D. Giugni90a, C. Giuliani48, M. Giulini58b, B.K. Gjelsten118_{, S. Gkaitatzis}155_{, I. Gkialas}155,l_{, L.K. Gladilin}98_{, C. Glasman}81_{, J. Glatzer}30_{, P.C.F. Glaysher}46_,

A. Glazov42_{, G.L. Glonti}64_{, M. Goblirsch-Kolb}100_{, J.R. Goddard}75_{, J. Godfrey}143_{, J. Godlewski}30_{, C. Goeringer}82_,

S. Goldfarb88_{, T. Golling}177_{, D. Golubkov}129_{, A. Gomes}125a,125b,125d_{, L.S. Gomez Fajardo}42_{, R. Gon¸calo}125a_,

J. Goncalves Pinto Firmino Da Costa137_{, L. Gonella}21_{, S. Gonz´alez de la Hoz}168_{, G. Gonzalez Parra}12_,

S. Gonzalez-Sevilla49, L. Goossens30, P.A. Gorbounov96, H.A. Gordon25, I. Gorelov104, B. Gorini30, E. Gorini72a,72b, A. Goriˇsek74_{, E. Gornicki}39_{, A.T. Goshaw}6_{, C. G¨ossling}43_{, M.I. Gostkin}64_{, M. Gouighri}136a_{, D. Goujdami}136c_,

M.P. Goulette49_{, A.G. Goussiou}139_{, C. Goy}5_{, S. Gozpinar}23_{, H.M.X. Grabas}137_{, L. Graber}54_{, I. Grabowska-Bold}38a_,

P. Grafstr¨om20a,20b_{, K-J. Grahn}42_{, J. Gramling}49_{, E. Gramstad}118_{, S. Grancagnolo}16_{, V. Grassi}149_{, V. Gratchev}122_,

H.M. Gray30_{, E. Graziani}135a_{, O.G. Grebenyuk}122_{, Z.D. Greenwood}78,m_{, K. Gregersen}77_{, I.M. Gregor}42_,

P. Grenier144, J. Griffiths8, A.A. Grillo138, K. Grimm71, S. Grinstein12,n, Ph. Gris34, Y.V. Grishkevich98, J.-F. Grivaz116, J.P. Grohs44, A. Grohsjean42, E. Gross173, J. Grosse-Knetter54, G.C. Grossi134a,134b, J. Groth-Jensen173_{, Z.J. Grout}150_{, L. Guan}33b_{, F. Guescini}49_{, D. Guest}177_{, O. Gueta}154_{, C. Guicheney}34_,

E. Guido50a,50b_{, T. Guillemin}116_{, S. Guindon}2_{, U. Gul}53_{, C. Gumpert}44_{, J. Gunther}127_{, J. Guo}35_{, S. Gupta}119_,

P. Gutierrez112_{, N.G. Gutierrez Ortiz}53_{, C. Gutschow}77_{, N. Guttman}154_{, C. Guyot}137_{, C. Gwenlan}119_,

C.B. Gwilliam73, A. Haas109, C. Haber15, H.K. Hadavand8, N. Haddad136e, P. Haefner21, S. Hageb¨ock21, Z. Hajduk39, H. Hakobyan178, M. Haleem42, D. Hall119, G. Halladjian89, K. Hamacher176, P. Hamal114, K. Hamano170_{, M. Hamer}54_{, A. Hamilton}146a_{, S. Hamilton}162_{, P.G. Hamnett}42_{, L. Han}33b_{, K. Hanagaki}117_,

K. Hanawa156_{, M. Hance}15_{, P. Hanke}58a_{, R. Hanna}137_{, J.B. Hansen}36_{, J.D. Hansen}36_{, P.H. Hansen}36_{, K. Hara}161_,

A.S. Hard174_{, T. Harenberg}176_{, F. Hariri}116_{, S. Harkusha}91_{, D. Harper}88_{, R.D. Harrington}46_{, O.M. Harris}139_,

P.F. Harrison171_{, F. Hartjes}106_{, S. Hasegawa}102_{, Y. Hasegawa}141_{, A. Hasib}112_{, S. Hassani}137_{, S. Haug}17_,

M. Hauschild30, R. Hauser89, M. Havranek126, C.M. Hawkes18, R.J. Hawkings30, A.D. Hawkins80, T. Hayashi161, D. Hayden89, C.P. Hays119, H.S. Hayward73, S.J. Haywood130, S.J. Head18, T. Heck82, V. Hedberg80, L. Heelan8, S. Heim121_{, T. Heim}176_{, B. Heinemann}15_{, L. Heinrich}109_{, J. Hejbal}126_{, L. Helary}22_{, C. Heller}99_{, M. Heller}30_,

S. Hellman147a,147b_{, D. Hellmich}21_{, C. Helsens}30_{, J. Henderson}119_{, R.C.W. Henderson}71_{, Y. Heng}174_{, C. Hengler}42_,

A. Henrichs177_{, A.M. Henriques Correia}30_{, S. Henrot-Versille}116_{, C. Hensel}54_{, G.H. Herbert}16_,

Y. Hern´andez Jim´enez168, R. Herrberg-Schubert16, G. Herten48, R. Hertenberger99, L. Hervas30, G.G. Hesketh77, N.P. Hessey106, R. Hickling75, E. Hig´on-Rodriguez168, E. Hill170, J.C. Hill28, K.H. Hiller42, S. Hillert21,

S.J. Hillier18_{, I. Hinchliffe}15_{, E. Hines}121_{, M. Hirose}158_{, D. Hirschbuehl}176_{, J. Hobbs}149_{, N. Hod}106_,

M.C. Hodgkinson140_{, P. Hodgson}140_{, A. Hoecker}30_{, M.R. Hoeferkamp}104_{, J. Hoffman}40_{, D. Hoffmann}84_,

J.I. Hofmann58a_{, M. Hohlfeld}82_{, T.R. Holmes}15_{, T.M. Hong}121_{, L. Hooft van Huysduynen}109_{, J-Y. Hostachy}55_,

S. Hou152_{, A. Hoummada}136a_{, J. Howard}119_{, J. Howarth}42_{, M. Hrabovsky}114_{, I. Hristova}16_{, J. Hrivnac}116_,

T. Hryn’ova5, C. Hsu146c, P.J. Hsu82, S.-C. Hsu139, D. Hu35, X. Hu25, Y. Huang42, Z. Hubacek30, F. Hubaut84, F. Huegging21_{, T.B. Huffman}119_{, E.W. Hughes}35_{, G. Hughes}71_{, M. Huhtinen}30_{, T.A. H¨ulsing}82_{, M. Hurwitz}15_,

N. Huseynov64,b_{, J. Huston}89_{, J. Huth}57_{, G. Iacobucci}49_{, G. Iakovidis}10_{, I. Ibragimov}142_{, L. Iconomidou-Fayard}116_,

E. Ideal177_{, P. Iengo}103a_{, O. Igonkina}106_{, T. Iizawa}172_{, Y. Ikegami}65_{, K. Ikematsu}142_{, M. Ikeno}65_{, Y. Ilchenko}31,o_,

D. Iliadis155_{, N. Ilic}159_{, Y. Inamaru}66_{, T. Ince}100_{, P. Ioannou}9_{, M. Iodice}135a_{, K. Iordanidou}9_{, V. Ippolito}57_,

A. Irles Quiles168, C. Isaksson167, M. Ishino67, M. Ishitsuka158, R. Ishmukhametov110, C. Issever119, S. Istin19a, J.M. Iturbe Ponce83, R. Iuppa134a,134b, J. Ivarsson80, W. Iwanski39, H. Iwasaki65, J.M. Izen41, V. Izzo103a, B. Jackson121_{, M. Jackson}73_{, P. Jackson}1_{, M.R. Jaekel}30_{, V. Jain}2_{, K. Jakobs}48_{, S. Jakobsen}30_{, T. Jakoubek}126_,

N. Javadov64,b, T. Jav˚urek48, L. Jeanty15, J. Jejelava51a,p, G.-Y. Jeng151, D. Jennens87, P. Jenni48,q, J. Jentzsch43, C. Jeske171, S. J´ez´equel5, H. Ji174, W. Ji82, J. Jia149, Y. Jiang33b, M. Jimenez Belenguer42, S. Jin33a, A. Jinaru26a, O. Jinnouchi158_{, M.D. Joergensen}36_{, K.E. Johansson}147a,147b_{, P. Johansson}140_{, K.A. Johns}7_{, K. Jon-And}147a,147b_,

G. Jones171_{, R.W.L. Jones}71_{, T.J. Jones}73_{, J. Jongmanns}58a_{, P.M. Jorge}125a,125b_{, K.D. Joshi}83_{, J. Jovicevic}148_,

X. Ju174_{, C.A. Jung}43_{, R.M. Jungst}30_{, P. Jussel}61_{, A. Juste Rozas}12,n_{, M. Kaci}168_{, A. Kaczmarska}39_{, M. Kado}116_,

H. Kagan110, M. Kagan144, E. Kajomovitz45, C.W. Kalderon119, S. Kama40, A. Kamenshchikov129, N. Kanaya156, M. Kaneda30, S. Kaneti28, V.A. Kantserov97, J. Kanzaki65, B. Kaplan109, A. Kapliy31, D. Kar53, K. Karakostas10, N. Karastathis10_{, M. Karnevskiy}82_{, S.N. Karpov}64_{, Z.M. Karpova}64_{, K. Karthik}109_{, V. Kartvelishvili}71_,

A.N. Karyukhin129_{, L. Kashif}174_{, G. Kasieczka}58b_{, R.D. Kass}110_{, A. Kastanas}14_{, Y. Kataoka}156_{, A. Katre}49_,

J. Katzy42_{, V. Kaushik}7_{, K. Kawagoe}69_{, T. Kawamoto}156_{, G. Kawamura}54_{, S. Kazama}156_{, V.F. Kazanin}108_,

M.Y. Kazarinov64_{, R. Keeler}170_{, R. Kehoe}40_{, M. Keil}54_{, J.S. Keller}42_{, J.J. Kempster}76_{, H. Keoshkerian}5_,

O. Kepka126, B.P. Kerˇsevan74, S. Kersten176, K. Kessoku156, J. Keung159, F. Khalil-zada11, H. Khandanyan147a,147b, A. Khanov113, A. Khodinov97, A. Khomich58a, T.J. Khoo28, G. Khoriauli21, A. Khoroshilov176, V. Khovanskiy96, E. Khramov64_{, J. Khubua}51b_{, H.Y. Kim}8_{, H. Kim}147a,147b_{, S.H. Kim}161_{, N. Kimura}172_{, O. Kind}16_{, B.T. King}73_,

M. King168_{, R.S.B. King}119_{, S.B. King}169_{, J. Kirk}130_{, A.E. Kiryunin}100_{, T. Kishimoto}66_{, D. Kisielewska}38a_,

F. Kiss48_{, T. Kittelmann}124_{, K. Kiuchi}161_{, E. Kladiva}145b_{, M. Klein}73_{, U. Klein}73_{, K. Kleinknecht}82_,

P. Klimek147a,147b, A. Klimentov25, R. Klingenberg43, J.A. Klinger83, T. Klioutchnikova30, P.F. Klok105, E.-E. Kluge58a, P. Kluit106, S. Kluth100, E. Kneringer61, E.B.F.G. Knoops84, A. Knue53, D. Kobayashi158, T. Kobayashi156_{, M. Kobel}44_{, M. Kocian}144_{, P. Kodys}128_{, P. Koevesarki}21_{, T. Koffas}29_{, E. Koffeman}106_,

L.A. Kogan119_{, S. Kohlmann}176_{, Z. Kohout}127_{, T. Kohriki}65_{, T. Koi}144_{, H. Kolanoski}16_{, I. Koletsou}5_{, J. Koll}89_,

A.A. Komar95,∗_{, Y. Komori}156_{, T. Kondo}65_{, N. Kondrashova}42_{, K. K¨oneke}48_{, A.C. K¨onig}105_{, S. K¨onig}82_,

T. Kono65,r_{, R. Konoplich}109,s_{, N. Konstantinidis}77_{, R. Kopeliansky}153_{, S. Koperny}38a_{, L. K¨opke}82_{, A.K. Kopp}48_,

K. Korcyl39, K. Kordas155, A. Korn77, A.A. Korol108,t, I. Korolkov12, E.V. Korolkova140, V.A. Korotkov129, O. Kortner100_{, S. Kortner}100_{, V.V. Kostyukhin}21_{, V.M. Kotov}64_{, A. Kotwal}45_{, C. Kourkoumelis}9_{, V. Kouskoura}155_,

A. Koutsman160a_{, R. Kowalewski}170_{, T.Z. Kowalski}38a_{, W. Kozanecki}137_{, A.S. Kozhin}129_{, V. Kral}127_,

V.A. Kramarenko98_{, G. Kramberger}74_{, D. Krasnopevtsev}97_{, M.W. Krasny}79_{, A. Krasznahorkay}30_{, J.K. Kraus}21_,

A. Kravchenko25_{, S. Kreiss}109_{, M. Kretz}58c_{, J. Kretzschmar}73_{, K. Kreutzfeldt}52_{, P. Krieger}159_{, K. Kroeninger}54_,

H. Kroha100, J. Kroll121, J. Kroseberg21, J. Krstic13a, U. Kruchonak64, H. Kr¨uger21, T. Kruker17, N. Krumnack63, Z.V. Krumshteyn64, A. Kruse174, M.C. Kruse45, M. Kruskal22, T. Kubota87, S. Kuday4a, S. Kuehn48, A. Kugel58c, A. Kuhl138_{, T. Kuhl}42_{, V. Kukhtin}64_{, Y. Kulchitsky}91_{, S. Kuleshov}32b_{, M. Kuna}133a,133b_{, J. Kunkle}121_,

A. Kupco126_{, H. Kurashige}66_{, Y.A. Kurochkin}91_{, R. Kurumida}66_{, V. Kus}126_{, E.S. Kuwertz}148_{, M. Kuze}158_,

J. Kvita114_{, A. La Rosa}49_{, L. La Rotonda}37a,37b_{, C. Lacasta}168_{, F. Lacava}133a,133b_{, J. Lacey}29_{, H. Lacker}16_,

D. Lacour79, V.R. Lacuesta168, E. Ladygin64, R. Lafaye5, B. Laforge79, T. Lagouri177, S. Lai48, H. Laier58a, L. Lambourne77, S. Lammers60, C.L. Lampen7, W. Lampl7, E. Lan¸con137, U. Landgraf48, M.P.J. Landon75, V.S. Lang58a_{, A.J. Lankford}164_{, F. Lanni}25_{, K. Lantzsch}30_{, S. Laplace}79_{, C. Lapoire}21_{, J.F. Laporte}137_{, T. Lari}90a_,

M. Lassnig30_{, P. Laurelli}47_{, W. Lavrijsen}15_{, A.T. Law}138_{, P. Laycock}73_{, B.T. Le}55_{, O. Le Dortz}79_{, E. Le Guirriec}84_,

E. Le Menedeu12_{, T. LeCompte}6_{, F. Ledroit-Guillon}55_{, C.A. Lee}152_{, H. Lee}106_{, J.S.H. Lee}117_{, S.C. Lee}152_{, L. Lee}177_,

G. Lefebvre79_{, M. Lefebvre}170_{, F. Legger}99_{, C. Leggett}15_{, A. Lehan}73_{, M. Lehmacher}21_{, G. Lehmann Miotto}30_,

X. Lei7, W.A. Leight29, A. Leisos155, A.G. Leister177, M.A.L. Leite24d, R. Leitner128, D. Lellouch173, B. Lemmer54, K.J.C. Leney77, T. Lenz106, G. Lenzen176, B. Lenzi30, R. Leone7, S. Leone123a,123b, K. Leonhardt44,

C. Leonidopoulos46_{, S. Leontsinis}10_{, C. Leroy}94_{, C.G. Lester}28_{, C.M. Lester}121_{, M. Levchenko}122_{, J. Levˆeque}5_,

D. Levin88_{, L.J. Levinson}173_{, M. Levy}18_{, A. Lewis}119_{, G.H. Lewis}109_{, A.M. Leyko}21_{, M. Leyton}41_{, B. Li}33b,u_,

B. Li84_{, H. Li}149_{, H.L. Li}31_{, L. Li}45_{, L. Li}33e_{, S. Li}45_{, Y. Li}33c,v_{, Z. Liang}138_{, H. Liao}34_{, B. Liberti}134a_{, P. Lichard}30_,

K. Lie166, J. Liebal21, W. Liebig14, C. Limbach21, A. Limosani87, S.C. Lin152,w, T.H. Lin82, F. Linde106, B.E. Lindquist149, J.T. Linnemann89, E. Lipeles121, A. Lipniacka14, M. Lisovyi42, T.M. Liss166, D. Lissauer25, A. Lister169_{, A.M. Litke}138_{, B. Liu}152_{, D. Liu}152_{, J.B. Liu}33b_{, K. Liu}33b,x_{, L. Liu}88_{, M. Liu}45_{, M. Liu}33b_{, Y. Liu}33b_,

M. Livan120a,120b_{, S.S.A. Livermore}119_{, A. Lleres}55_{, J. Llorente Merino}81_{, S.L. Lloyd}75_{, F. Lo Sterzo}152_,

E. Lobodzinska42_{, P. Loch}7_{, W.S. Lockman}138_{, T. Loddenkoetter}21_{, F.K. Loebinger}83_{, A.E. Loevschall-Jensen}36_,

A. Loginov177_{, C.W. Loh}169_{, T. Lohse}16_{, K. Lohwasser}42_{, M. Lokajicek}126_{, V.P. Lombardo}5_{, B.A. Long}22_,

J.D. Long88, R.E. Long71, L. Lopes125a, D. Lopez Mateos57, B. Lopez Paredes140, I. Lopez Paz12, J. Lorenz99, N. Lorenzo Martinez60_{, M. Losada}163_{, P. Loscutoff}15_{, X. Lou}41_{, A. Lounis}116_{, J. Love}6_{, P.A. Love}71_{, A.J. Lowe}144,e_,

F. Lu33a_{, H.J. Lubatti}139_{, C. Luci}133a,133b_{, A. Lucotte}55_{, F. Luehring}60_{, W. Lukas}61_{, L. Luminari}133a_,

O. Lundberg147a,147b_{, B. Lund-Jensen}148_{, M. Lungwitz}82_{, D. Lynn}25_{, R. Lysak}126_{, E. Lytken}80_{, H. Ma}25_,

L.L. Ma33d_{, G. Maccarrone}47_{, A. Macchiolo}100_{, J. Machado Miguens}125a,125b_{, D. Macina}30_{, D. Madaffari}84_,

R. Madar48, H.J. Maddocks71, W.F. Mader44, A. Madsen167, M. Maeno8, T. Maeno25, E. Magradze54, K. Mahboubi48, J. Mahlstedt106, S. Mahmoud73, C. Maiani137, C. Maidantchik24a, A.A. Maier100,

A. Maio125a,125b,125d_{, S. Majewski}115_{, Y. Makida}65_{, N. Makovec}116_{, P. Mal}137,y_{, B. Malaescu}79_{, Pa. Malecki}39_,