Observation of an Excited $B_c^\pm$ Meson State with the ATLAS Detector

arXiv:1407.1032v2 [hep-ex] 9 Nov 2015

EUROPEAN ORGANISATION FOR NUCLEAR RESEARCH (CERN)

CERN-PH-EP-2014-137

Submitted to: Physical Review Letters

Observation of an Excited

B

±

c

Meson State with the ATLAS

Detector

The ATLAS Collaboration

Abstract

A search for excited states of the

B

±

c

meson is performed using 4.9 fb

−1

_{of 7 TeV and 19.2 fb}

−1

_of

8 TeV

pp

collision data collected by the ATLAS experiment at the LHC. A new state is observed through

its hadronic transition to the ground state, with the latter detected in the decay

B

±

c

→ J/ψπ

±

. The

state appears in the

m(B

±

c

π

+

π

−

) − m(B

± c

) − 2m(π

±

)

mass difference distribution with a significance

of 5.2 standard deviations. The mass of the observed state is

_{6842 ± 4 ± 5}

MeV, where the first error

is statistical and the second is systematic. The mass and decay of this state are consistent with

expectations for the second

S

-wave state of the

B

±

c

meson,

B

± c

(2S)

.

c

Observation of an Excited B

c

Meson State with the ATLAS Detector

ATLAS Collaboration

A search for excited states of the B±

c meson is performed using 4.9 fb

−1_{of 7 TeV and 19.2 fb}−1

of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic transition to the ground state, with the latter detected in the decay B±

c →

J/ψπ±

. The state appears in the m(B±

cπ + π− ) − m(B± c) − 2m(π ±

) mass difference distribution with a significance of 5.2 standard deviations. The mass of the observed state is 6842 ± 4 ± 5 MeV, where the first error is statistical and the second is systematic. The mass and decay of this state are consistent with expectations for the second S-wave state of the B±

c meson, B ± c(2S).

PACS numbers: 14.40.Nd

The B±

c meson was first observed by the CDF

experi-ment in the semileptonic decay mode [1], and its hadronic decay mode was observed later by both CDF [2] and D0 [3] experiments. The B±

c meson has also been observed

by the LHCb experiment in various decay modes [4]. Ex-cited states of the B±

c meson have not previously been

observed. The spectrum and properties of the B± c family

are predicted by non-relativistic potential models, per-turbative QCD, and lattice calculations [5]. Measuments of the ground and excited states through fully re-constructed channels will provide tests of the predictions of these models and ultimately the opportunity to extract information on the strong interaction potential.

The second S-wave state, B±

c (2S), is predicted to have

a mass in the range 6835–6917 MeV [5]. The next S-wave state, B±

c (3S), is predicted to have a mass above the

threshold for decay into a BD meson pair. Both the 1S and 2S states have pseudoscalar (0−

) and vector (1−

) spin states that are predicted to differ in mass by about 20–50 MeV. Transitions between the spin states occur through soft photon radiation that escapes identification in ATLAS; the spin states cannot be separated by this analysis.

This Letter presents the observation of a new state whose mass is consistent with predictions for the B±

c (2S),

the second S-wave state of the B±

c meson. The B ± c (2S)

state is reconstructed in the decay to the B±

c meson and

two oppositely charged pions, with the B±

c reconstructed

through its decay to J/ψπ±

, J/ψ → µ+_µ−

.

The ATLAS collaboration at the Large Hadron Col-lider (LHC) uses a general-purpose particle detector [6], consisting of several subsystems including the inner de-tector (ID), the electromagnetic and hadronic calorime-ters, and the muon spectrometer (MS). Muon reconstruc-tion at ATLAS makes use of both the ID and the MS.

Muons pass through the calorimeters and reach the MS if their momentum is above approximately 3 GeV. The inner detector features a three-component track-ing system, consisttrack-ing of two silicon-based detectors, the pixel detector and the microstrip semiconductor tracker (SCT), and the transition radiation tracker (TRT). ID tracks are reconstructed if their transverse momentum,

pT [7], is greater than 400 MeV and the magnitude of

their pseudorapidity, |η|, is less than 2.5. Muon candi-dates are formed from a stand-alone MS track that is matched to an ID track [8]. In this analysis the MS is only used to identify muons, while their momentum is measured using the ID information only.

The trigger system [9] comprises three levels: the hardware-based Level-1 trigger and the High-Level Trig-gers (HLT), consisting of the Level-2 trigger and the Event Filter (EF). The Level-1 trigger uses resistive plate chambers (RPC) and thin gap chambers (TGC) to trig-ger muons in the pseudorapidity ranges of |η| < 1.05 and 1.05 < |η| < 2.5, respectively. One or more regions of interest identified by the Level-1 muon trigger seed the HLT muon online reconstruction algorithms, where the responses from both the ID and the MS are combined. For this analysis the HLT selection for the J/ψ requires two muons, respectively µ1and µ2, originating at a

com-mon vertex, with the invariant mass of the muon pair ly-ing between 2.5 GeV and 4.3 GeV. The individual muon pTthresholds are pT(µ1) > 6 GeV and pT(µ2) > 4 GeV.

This study uses pp collision data collected in the years 2011 (√s = 7 TeV) and 2012 (√s = 8 TeV) by the AT-LAS experiment. The datasets used correspond to an integrated luminosity of 4.9 fb−1 _{and 19.2 fb}−1_,

respec-tively. The luminosity estimate has an uncertainty of 1.8% in 2011 [11] and 2.8% in 2012.

To improve the resolution, peaks are sought in the distribution of the variable Q = m(B±

c ππ) − m(B ± c ) −

2m(π±

), where m(B±

c ) is the offline reconstructed

invari-ant mass of the B±

c candidate, m(B ±

c ππ) is the invariant

mass of the B±

c candidate combined with two charged

pion candidates, and m(π±

) is the charged pion mass [10]. The B±

c candidates are reconstructed through the

decay B±

c → J/ψ(µ+µ

−_)π±_{. Since hadronic decays of}

excited B meson states have no observable displacement from the pp interaction point, these candidates are then combined with two charged pion candidates both orig-inating at the corresponding pp interaction point. The mass difference (Q) distribution is formed and analyzed in the range 0 − 700 MeV.

The B±

separately for 7 TeV and 8 TeV data using the corre-sponding Monte Carlo (MC) samples, produced in the ATLAS simulation framework [12, 13]. Differences be-tween the 7 TeV and 8 TeV selection criteria are due to the higher√s and the number of simultaneous pp inter-actions per bunch crossing hereafter called pile-up. The increase in the B±

c production cross section between the

7 TeV and 8 TeV MC samples is approximately 3%. The PYTHIA 6 and 8 MC generators [14, 15], tuned for the LHC conditions [16], are used along with a dedicated PYTHIA extension for B±

c meson production, based on

calculations from Ref. [17]. The following MC samples are used to optimize the event selection criteria (charge conjugates implied): B+

c decay modes J/ψπ+, J/ψK+,

J/ψρ+ _(ρ+_{→ π}0_π+_{), J/ψµ}+_{ν, J/ψπ}0_π+_{, J/ψπ}+_π−

π+_,

as well as J/ψX produced inclusively or from b¯b. The MC simulated events are treated in exactly the same way as the collision data, and the same analysis selections are always applied. The exclusive (B+

c ) channels are

gener-ated with PYTHIA 6, and inclusive (J/ψX) channels are generated with PYTHIA 8.

This analysis involves several steps. First the J/ψ can-didates are formed as described below. Then a pion track candidate from the same vertex is added to form a B± c

meson candidate. Finally, the B±

c (2S) candidates are

formed by adding two pion candidates originating at the primary vertex (PV; the selection of the primary vertex is defined below).

The J/ψ candidates are reconstructed from pairs of oppositely charged muons. These pairs are fitted to a common vertex with the procedure described in Ref. [18]. The following requirements are applied to each J/ψ can-didate:

• The pT of the higher-pT muon candidate to be

above 6 GeV, and the pT of the lower-pT muon

candidate to be above 4 GeV; these are approxi-mately the pT values for which the trigger is fully

efficient.

• The J/ψ vertex fit chi-square per degree of freedom χ2_{/N DOF < 15 (this selection keeps more than}

99.9% of the candidates, and is included only to remove spurious dimuon combinations).

• The invariant mass resolution of the J/ψ depends on the direction of the muons, with more forward candidates showing poorer resolutions. The sample is split into three categories and selection require-ments are optimized for each of them: (1) both muons have |η| < 1.05, (2) one muon has |η| < 1.05 and the other one has 1.05 < |η| < 2.5, (3) both muons have 1.05 < |η| < 2.5. The invariant mass m(µ+_µ−_{) is calculated from the track parameters}

adjusted by the common-vertex fit to be in a three standard deviation ±3σ mass window around the world average mass m(J/ψ) [10], where the J/ψ

re-constructed width σ varies in the range 40–90 MeV depending on muon reconstruction precision in dif-ferent regions of pseudorapidity and on the data-taking period.

Selection requirements for the B±

c were chosen by

max-imizing S/√S + B, using MC events. Here S is the num-ber of signal events and B refers to the numnum-ber of back-ground MC events scaled according to the production cross section. The production cross sections are taken from the MC generators’ predictions. The optimiza-tion has been carried out separately for the two different datasets.

The pion candidate from the B±

c is required to have

pT> 4 GeV. Hit requirements in the pixel detector and

SCT are imposed on all tracks to ensure a reliable impact parameter reconstruction.

B±

c candidates are reconstructed by fitting two muon

tracks from the J/ψ candidate together with a pion can-didate track to a common vertex. The invariant mass of the two muons is constrained to the world average of m(J/ψ). The yields per unit of integrated luminos-ity, and the central values of the dimuon invariant mass distributions are verified to be consistent within each dataset.

A significant part of the combinatorial background consists of real J/ψ candidates combined with candidate pions that are not associated with a B±

c → J/ψπ

±_decay.

This background is reduced by imposing a lower cut on d0/σ(d0); d0 here represents the projection of the pion

track impact parameter relative to the primary vertex onto the transverse plane, and σ(d0) is the track-by-track

uncertainty on d0. Pion candidates are required to have

d0/σ(d0) > 5 for 7 TeV data and > 4.5 for 8 TeV data. In

7 TeV data the PV is defined as the collision vertex with the highest summed scalar p2

T of its constituent tracks.

In 8 TeV data – the data collected with higher pile-up – the PV is identified as the vertex closest in three di-mensions to the reconstructed decay vertex of the B± c

candidate. All reconstructed B±

c candidates are also

re-quired to satisfy the following selection criteria:

• the J/ψπ vertex fit χ2_{/N DOF < 2 for 7 TeV and}

< 1.5 for 8 TeV data;

• the pTof the Bc±candidate to be above 15 GeV for

7 TeV and above 18 GeV for 8 TeV data.

Figure 1 shows the invariant mass distributions for the B±

c candidates for 7 TeV data and 8 TeV data in the

mass range 5620–6820 MeV. Both distributions are fitted separately using an extended unbinned maximum likeli-hood fit, with a Gaussian function modeling the signal and an exponential modeling the background shape. The various exclusive B±

c decay modes mentioned above are

shown to have negligible contribution to the background shape. The results of the fits are summarized in Table

I. The fitted mass values are consistent with the world average for the B±

c mass [10]. The signal yield per fb −1

of the B±

c is lower in 8 TeV data due to the harder pT

requirements. The stability of the B±

c yield was checked

through its normalization to B±

→ J/ψK±

decays that were reconstructed with similar requirements.

[MeV] π ψ J/ m 5800 6000 6200 6400 6600 6800 Events / 40 MeV 0 10 20 30 40 50 60 70 _ATLAS -1 Ldt = 4.9 fb

∫

= 7 TeV s 8 MeV ± = 6282 c B m 23 ± = 100 c B N 12 MeV ± = 49 σ [MeV] π ψ J/ m 5800 6000 6200 6400 6600 6800 Events / 40 MeV 0 20 40 60 80 100 120 140 160 _ATLAS -1 Ldt = 19.2 fb

∫

= 8 TeV s 6 MeV ± = 6277 c B m 25 ± = 227 c B N 8 MeV ± = 50 σ

FIG. 1: Invariant mass distributions of the reconstructed B±

c →J/ψπ

±

candidates in 7 TeV data (top) and in 8 TeV data (bottom). The data are represented by the points with error bars (statistical only). The solid line is the projection of the results of the unbinned maximum likelihood fit to all candidates in the mass range 5620–6820 MeV. The dashed line is the projection of the background component of the same fit.

Data Signal events Peak mean [MeV] Peak width [MeV] 7 TeV 100±23 6282±8 49±12 8 TeV 227±25 6277±6 50±8 TABLE I: The results of the unbinned maximum likelihood fits of the invariant mass distribution of the B±

c candidates.

Systematic uncertainties are not included.

The reconstruction of the excited state candidates uses the B±

c ground state candidates within ±3σ of the fitted

mass value of the corresponding dataset. These candi-dates are combined as described below with two pion candidate tracks associated with the corresponding pri-mary vertex. The pTthreshold of the pion candidates is

400 MeV. No additional selection requirement is applied to the B±

c (2S) pion candidates. The three tracks from

the secondary vertex and the two tracks from the pri-mary vertex are refitted simultaneously with the follow-ing constraints given by the decay topology: the refitted triplet of the B±

c tracks and the pair of PV pion tracks

must intersect in two separate B± c and B

±

c (2S) vertices.

The invariant mass of the refitted muon tracks is con-strained to the J/ψ world average mass, and the com-bined momentum of the refitted B±

c tracks must point to

the B±

c(2S) vertex. When multiple B ±

c (2S) candidates

are found in the same event, the one with the best χ2

value returned by the fitter is kept as an excited state candidate. Wrong-charge combinations (B±

c π+π+ and

B± c π

−_π−_{) are kept separately for comparison with the}

combinatorial background shape in the right-charge com-binations (oppositely charged pion pairs).

Figure 2 shows the mass difference distribution m(B±

c ππ) − m(B ±

c ) − 2m(π) for the right-charge

com-binations B± c π+π

−

as well as the wrong-charge combi-nations.

A structure is observed in the mass difference distri-bution. In order to characterize it, an unbinned max-imum likelihood fit to the right-charge combinations is performed. The fit includes a third-order polynomial to model the background and a Gaussian function for the structure. The background shape resulting from the fit is verified to be consistent with the wrong-charge combina-tions (which are not used to constrain the model in the right-charge fit) by fitting the same shape to them, with the normalization as the only free parameter. Alternative models for the signal and the background parameteriza-tions are studied as sources of systematic uncertainty. A Breit–Wigner contribution was tested in convolution with the Gaussian function and was found to be negli-gible, implying that the natural width of the structure is small relative to the detector resolution. The result-ing fit parameters (with statistical uncertainties only), as well as the distributions of the wrong-charge (B±

c π+π+,

B± c π

−_π−_{) combinations are shown in figure 2. The}

wrong-charge combinations are normalized to the same yield as the right-charge background.

The relative B± c (2S)/B

±

c yield ratio is verified to be

statistically consistent between the 7 TeV and 8 TeV data.

The fit finds the peak at a mass difference (Q) value of 288.2 ± 5.1 MeV in the 7 TeV data and 288.4 ± 4.8 MeV in the 8 TeV data. The fit yields 22 ± 6 signal events in the 7 TeV data and 35 ± 13 events in the 8 TeV data. The Gaussian width of the structure is found to be 18.2 ± 3.8 MeV in the 7 TeV data and 17.6 ± 4.0 MeV in the 8 TeV data. All uncertainties mentioned in this

) [MeV] π )-2m( c )-m(B π π c m(B 0 100 200 300 400 500 600 700 Events / 20 MeV 0 2 4 6 8 10 12 14 16 18 20 -1 Ldt = 4.9 fb

∫

_{s = 7 TeV} Data Wrong-charge combinations ATLAS ATLAS _ππ = 288 ± 5 MeV c B Q 4 MeV ± = 18 π π c B σ 6 ± = 22 π π c B N ) [MeV] π )-2m( c )-m(B π π c m(B 0 100 200 300 400 500 600 700 Events / 20 MeV 0 5 10 15 20 25 30 35 40 -1 Ldt = 19.2 fb

∫

_{s = 8 TeV} ATLAS ATLAS Data Wrong-charge combinations 5 MeV ± = 288 π π c B Q 4 MeV ± = 18 π π c B σ 13 ± = 35 π π c B N FIG. 2: The Q = m(B± cππ) − m(B ± c) − 2m(π ± ) distribution for the right-charge combinations (points with error bars) and for the same (wrong) pion charge combinations (shaded his-togram) in 7 TeV data (top) and in 8 TeV data (bottom). The wrong-charge combinations are normalized to the same yield as the right-charge background. The solid line is the projection of the results of the unbinned maximum likelihood fit to all candidates in the range 0–700 MeV. The dashed line is the projection of the background component of the same fit.

paragraph do not include systematic uncertainties. There are two dominant sources of systematic uncer-tainty on the position of the peak. One comes from the uncertainty on the mass of the B±

c ground state

candidate and is largely canceled in the mass differ-ence distribution. The other involves systematic uncer-tainties in the fit of the mass difference distribution it-self. The uncertainty on the mass of the B±

c (2S)

can-didate is dominated by the fitting procedure and esti-mated below to be about 3.6 MeV. The contribution from the uncertainty on the pion momentum scale to the B±

c mass is 1.2 MeV. The residual uncertainty from

the B±

c candidate mass in the mass difference

distribu-tion, δm_B± c(2S) = δmB ± c × (mB ± c)/mB ± c(2S), where the δm_B±

c is the world average uncertainty on the B

± c mass

[10], is about 1.7 MeV. The systematic uncertainty on

the mass difference introduced by the fitting procedure is estimated by:

• varying the background model. An exponential threshold function (f (Q) ∽ Qa_e−bQ_{, where a and b}

are free parameters) and second- and fourth-order polynomials were considered as alternatives, result-ing in a 3.4 MeV systematic uncertainty;

• varying the fit mass range from 0–700 MeV to 0– 1500 MeV, results in a 1.2 MeV contribution to the systematic uncertainty;

• using different models for the signal. A single Breit–Wigner function, a Breit–Wigner function convolved with a Gaussian function, and a double Gaussian function were considered. This results in a negligible systematic uncertainty, compared to the above two;

In each case the largest difference between any of the variations mentioned and the default fit model is used as the systematic uncertainty. The values are calculated as the weighted mean of the 7 and 8 TeV mass values.

An additional systematic uncertainty of 2 MeV is ob-tained from the study of the mass bias in the selection of the candidate with the best χ2_{of the vertex fit.}

The various sources of systematic uncertainty are treated as uncorrelated. The total averaged systematic uncertainty propagated to the mass value of the new structure is approximately 4.1 MeV.

The significance of the new structure is evaluated with pseudo-experiments. A large number of background-only mass difference distributions are generated. Parameters of the generation are taken from the fit with their un-certainties to account for systematic effects. The back-ground shape is scaled to the observed number of events. The mean mass value of the signal contribution is left free to vary within the theoretically motivated range (6835–6917 MeV) to evaluate the “look-elsewhere effect” [19]. The significance is calculated as the fraction of the pseudo-experiments in which the difference of the loga-rithms of fit likelihoods ∆lnL with and without signal is larger than in the data. In terms of standard deviations the significance of the observation is 3.7σ in the 7 TeV data and 4.5σ in the 8 TeV data. For the combined 7 TeV and 8 TeV dataset the total significance of the observation is found to be 5.2σ. The local significance of the observation, obtained by fixing the mean value of the signal component, is 5.4σ.

In conclusion, the distribution of the mass difference Q = m(B±

c π+π −

) − m(B±

c ) − 2m(π

±_{) for events with}

the B±

c meson reconstructed in its decay to J/ψπ ± _has

been investigated in pp collisions at the LHC using the ATLAS detector. The analysis is based on an integrated luminosity of 4.9 (19.2) fb−1 _{of pp collisions at a}

at Q = 288.3 ± 3.5 ± 4.1 MeV (calculated as the error weighted mean of the 7 TeV and 8 TeV mass values) corresponding to a mass of 6842 ± 4 ± 5 MeV, where the first error is statistical and the second is systematic. The significance of the observation is 5.2σ with the “look elsewhere effect” taken into account, and the local sig-nificance is 5.4σ. Within the uncertainties, the mass of the resonance corresponding to the observed structure is consistent with the predicted mass of the B±

c(2S) state.

We thank CERN for the very successful operation of the LHC, as well as the support staff from our institu-tions, without whom ATLAS could not be operated effi-ciently.

We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWF 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. Abbott}112_{, J. Abdallah}152_{, S. Abdel Khalek}116_{, O. Abdinov}11_{, R. Aben}106_{, B. Abi}113_{, M. Abolins}89_,

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 Verzini}70_{, M. Aleksa}30_{, I.N. Aleksandrov}64_{, C. Alexa}26a_{, G. Alexander}154_,

G. Alexandre49_{, T. Alexopoulos}10_{, M. Alhroob}165a,165c_{, G. Alimonti}90a_{, L. Alio}84_{, J. Alison}31_{, B.M.M. Allbrooke}18_,

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. Ancu}49_{, N. Andari}30_{, T. Andeen}35_{, C.F. Anders}58b_{, G. Anders}30_{, K.J. Anderson}31_,

A. Andreazza90a,90b_{, V. Andrei}58a_{, X.S. Anduaga}70_{, S. Angelidakis}9_{, I. Angelozzi}106_{, P. Anger}44_{, A. Angerami}35_,

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. Arnold48, M. Arratia28, O. Arslan21, A. Artamonov96, G. Artoni23, S. Asai156, N. Asbah42, A. Ashkenazi154, B. ˚Asman147a,147b, L. Asquith6, K. Assamagan25, R. Astalos145a, M. Atkinson166, N.B. Atlay142, B. Auerbach6, K. Augsten127, M. Aurousseau146b, G. Avolio30, G. Azuelos94,d, Y. Azuma156, M.A. Baak30, 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. Barberio}87_{, D. Barberis}50a,50b_{, M. Barbero}84_{, T. Barillari}100_{, M. Barisonzi}176_{, T. Barklow}144_,

N. Barlow28_{, B.M. Barnett}130_{, R.M. Barnett}15_{, Z. Barnovska}5_{, A. Baroncelli}135a_{, G. Barone}49_{, A.J. Barr}119_,

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. Bee}149_{, L.J. Beemster}106_{, T.A. Beermann}176_{, M. Begel}25_{, K. Behr}119_,

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. Bernat}77_{, C. Bernius}78_{, F.U. Bernlochner}170_{, T. Berry}76_{, P. Berta}128_{, C. Bertella}84_,

G. Bertoli147a,147b_{, F. Bertolucci}123a,123b_{, D. Bertsche}112_{, M.I. Besana}90a_{, G.J. Besjes}105_{, O. Bessidskaia}147a,147b_,

M. 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. Blair}6_{, J.-B. Blanchard}137_{, T. Blazek}145a_{, I. Bloch}42_{, C. Blocker}23_{, W. Blum}82,∗_,

U. Blumenschein54_{, G.J. Bobbink}106_{, V.S. Bobrovnikov}108_{, S.S. Bocchetta}80_{, A. Bocci}45_{, C. Bock}99_{, C.R. Boddy}119_,

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. Bourdarios}116_{, N. Bousson}113_{, S. Boutouil}136d_{, A. Boveia}31_{, J. Boyd}30_{, I.R. Boyko}64_,

J. Bracinik18, A. Brandt8, G. Brandt15, O. Brandt58a, U. Bratzler157, B. Brau85, J.E. Brau115, H.M. Braun176,∗, S.F. Brazzale165a,165c, B. Brelier159, K. Brendlinger121, A.J. Brennan87, R. Brenner167, S. Bressler173,

K. Bristow146c, T.M. Bristow46, D. Britton53, F.M. Brochu28, I. Brock21, R. Brock89, C. Bromberg89, J. Bronner100, G. Brooijmans35_{, T. Brooks}76_{, W.K. Brooks}32b_{, J. Brosamer}15_{, E. Brost}115_{, J. Brown}55_,

P.A. Bruckman de Renstrom39_{, D. Bruncko}145b_{, R. Bruneliere}48_{, S. Brunet}60_{, A. Bruni}20a_{, G. Bruni}20a_,

M. Bruschi20a_{, L. Bryngemark}80_{, T. Buanes}14_{, Q. Buat}143_{, F. Bucci}49_{, P. Buchholz}142_{, R.M. Buckingham}119_,

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_,

D. Caforio20a,20b_{, O. Cakir}4a_{, P. Calafiura}15_{, A. Calandri}137_{, G. Calderini}79_{, P. Calfayan}99_{, R. Calkins}107_,

L.P. Caloba24a_{, D. Calvet}34_{, S. Calvet}34_{, R. Camacho Toro}49_{, S. Camarda}42_{, D. Cameron}118_{, L.M. Caminada}15_,

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. Caputo82, R. Cardarelli134a, T. Carli30, G. Carlino103a, L. Carminati90a,90b, S. Caron105, 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. Catmore}118_{, A. Cattai}30_{, G. Cattani}134a,134b_{, S. Caughron}89_{, V. Cavaliere}166_{, D. Cavalli}90a_,

M. Cavalli-Sforza12_{, V. Cavasinni}123a,123b_{, F. Ceradini}135a,135b_{, B. Cerio}45_{, K. Cerny}128_{, A.S. Cerqueira}24b_,

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. Cheng}31_{, A. Cheplakov}64_{, R. Cherkaoui El Moursli}136e_{, V. Chernyatin}25,∗_{, E. Cheu}7_,

L. Chevalier137_{, V. Chiarella}47_{, G. Chiefari}103a,103b_{, J.T. Childers}6_{, A. Chilingarov}71_{, G. Chiodini}72a_,

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. Clark}49_{, P.J. Clark}46_{, R.N. Clarke}15_{, W. Cleland}124_{, J.C. Clemens}84_{, C. Clement}147a,147b_,

Y. Coadou84_{, M. Cobal}165a,165c_{, A. Coccaro}139_{, J. Cochran}63_{, L. Coffey}23_{, J.G. Cogan}144_{, J. Coggeshall}166_,

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-Gonzalez}12_{, G. Cortiana}100_{, G. Costa}90a_{, M.J. Costa}168_{, D. Costanzo}140_{, D. Cˆot´e}8_,

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. Dafinca}119_{, T. Dai}88_{, O. Dale}14_{, F. Dallaire}94_{, C. Dallapiccola}85_{, M. Dam}36_{, A.C. Daniells}18_,

M. Dano Hoffmann137_{, V. Dao}105_{, G. Darbo}50a_{, S. Darmora}8_{, J.A. Dassoulas}42_{, A. Dattagupta}60_{, W. Davey}21_,

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 Pedis}133a_{, A. De Salvo}133a_{, U. De Sanctis}165a,165b_{, A. De Santo}150_{, J.B. De Vivie De Regie}116_,

W.J. Dearnaley71_{, R. Debbe}25_{, C. Debenedetti}138_{, B. Dechenaux}55_{, D.V. Dedovich}64_{, I. Deigaard}106_{, J. Del Peso}81_,

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 Domenico}133a,133b_{, C. Di Donato}103a,103b_{, A. Di Girolamo}30_{, B. Di Girolamo}30_,

A. Di Mattia153_{, B. Di Micco}135a,135b_{, R. Di Nardo}47_{, A. Di Simone}48_{, R. Di Sipio}20a,20b_{, D. Di Valentino}29_,

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. Dolejsi}128_{, Z. Dolezal}128_{, B.A. Dolgoshein}97,∗_{, M. Donadelli}24d_{, S. Donati}123a,123b_,

P. Dondero120a,120b_{, J. Donini}34_{, J. Dopke}130_{, A. Doria}103a_{, M.T. Dova}70_{, A.T. Doyle}53_{, M. Dris}10_{, J. Dubbert}88_,

S. Dube15, E. Dubreuil34, E. Duchovni173, G. Duckeck99, O.A. Ducu26a, D. Duda176, A. Dudarev30, F. Dudziak63, 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. Emeliyanov}130_{, Y. Enari}156_{, O.C. Endner}82_{, M. Endo}117_{, R. Engelmann}149_{, J. Erdmann}177_,

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_,

P. Farthouat30_{, F. Fassi}136e_{, P. Fassnacht}30_{, D. Fassouliotis}9_{, A. Favareto}50a,50b_{, L. Fayard}116_{, P. Federic}145a_,

O.L. Fedin122,j_{, W. Fedorko}169_{, M. Fehling-Kaschek}48_{, S. Feigl}30_{, L. Feligioni}84_{, C. Feng}33d_{, E.J. Feng}6_{, H. Feng}88_,

A.B. Fenyuk129, S. Fernandez Perez30, S. Ferrag53, J. Ferrando53, A. Ferrari167, P. Ferrari106, R. Ferrari120a, D.E. Ferreira de Lima53, A. Ferrer168, D. Ferrere49, C. Ferretti88, A. Ferretto Parodi50a,50b, M. Fiascaris31, F. Fiedler82, A. Filipˇciˇc74, M. Filipuzzi42, F. Filthaut105, M. Fincke-Keeler170, K.D. Finelli151,

M.C.N. Fiolhais125a,125c_{, L. Fiorini}168_{, A. Firan}40_{, A. Fischer}2_{, J. Fischer}176_{, W.C. Fisher}89_{, E.A. Fitzgerald}23_,

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. Franklin}57_{, S. Franz}61_{, M. Fraternali}120a,120b_{, S.T. French}28_{, C. Friedrich}42_{, F. Friedrich}44_,

D. Froidevaux30_{, J.A. Frost}28_{, C. Fukunaga}157_{, E. Fullana Torregrosa}82_{, B.G. Fulsom}144_{, J. Fuster}168_,

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. Gatti}47_{, G. Gaudio}120a_{, B. Gaur}142_{, L. Gauthier}94_{, P. Gauzzi}133a,133b_{, I.L. Gavrilenko}95_,

C. Gay169_{, G. Gaycken}21_{, E.N. Gazis}10_{, P. Ge}33d_{, Z. Gecse}169_{, C.N.P. Gee}130_{, D.A.A. Geerts}106_,

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. Gillam}28_{, D. Gillberg}30_{, G. Gilles}34_{, D.M. Gingrich}3,d_{, N. Giokaris}9_{, M.P. Giordani}165a,165c_,

R. Giordano103a,103b_{, F.M. Giorgi}20a_{, F.M. Giorgi}16_{, P.F. Giraud}137_{, D. Giugni}90a_{, C. Giuliani}48_{, M. Giulini}58b_,

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. Goossens}30_{, P.A. Gorbounov}96_{, H.A. Gordon}25_{, I. Gorelov}104_{, B. Gorini}30_{, E. Gorini}72a,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. Griffiths}8_{, A.A. Grillo}138_{, K. Grimm}71_{, S. Grinstein}12,n_{, Ph. Gris}34_{, Y.V. Grishkevich}98_,

J.-F. Grivaz116_{, J.P. Grohs}44_{, A. Grohsjean}42_{, E. Gross}173_{, J. Grosse-Knetter}54_{, G.C. Grossi}134a,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. Haas}109_{, C. Haber}15_{, H.K. Hadavand}8_{, N. Haddad}136e_{, P. Haefner}21_{, S. Hageb¨ock}21_,

Z. Hajduk39_{, H. Hakobyan}178_{, M. Haleem}42_{, D. Hall}119_{, G. Halladjian}89_{, K. Hamacher}176_{, P. Hamal}114_,

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. Hauser}89_{, M. Havranek}126_{, C.M. Hawkes}18_{, R.J. Hawkings}30_{, A.D. Hawkins}80_{, T. Hayashi}161_,

D. Hayden89_{, C.P. Hays}119_{, H.S. Hayward}73_{, S.J. Haywood}130_{, S.J. Head}18_{, T. Heck}82_{, V. Hedberg}80_{, L. Heelan}8_,

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. Hickling}75_{, E. Hig´on-Rodriguez}168_{, E. Hill}170_{, J.C. Hill}28_{, K.H. Hiller}42_{, S. Hillert}21_,

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. Hsu}146c_{, P.J. Hsu}82_{, S.-C. Hsu}139_{, D. Hu}35_{, X. Hu}25_{, Y. Huang}42_{, Z. Hubacek}30_{, F. Hubaut}84_,

F. Huegging21_{, T.B. Huffman}119_{, E.W. Hughes}35_{, G. Hughes}71_{, M. Huhtinen}30_{, T.A. H¨ulsing}82_{, M. Hurwitz}15_,

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. Jackson73, P. Jackson1, M.R. Jaekel30, V. Jain2, K. Jakobs48, S. Jakobsen30, T. Jakoubek126, J. Jakubek127_{, D.O. Jamin}152_{, D.K. Jana}78_{, E. Jansen}77_{, H. Jansen}30_{, J. Janssen}21_{, M. Janus}171_{, G. Jarlskog}80_,

N. Javadov64,b_{, T. Jav˚urek}48_{, L. Jeanty}15_{, J. Jejelava}51a,p_{, G.-Y. Jeng}151_{, D. Jennens}87_{, P. Jenni}48,q_{, J. Jentzsch}43_,

C. Jeske171_{, S. J´ez´equel}5_{, H. Ji}174_{, W. Ji}82_{, J. Jia}149_{, Y. Jiang}33b_{, M. Jimenez Belenguer}42_{, S. Jin}33a_{, A. Jinaru}26a_,

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. Kagan}144_{, E. Kajomovitz}45_{, C.W. Kalderon}119_{, S. Kama}40_{, A. Kamenshchikov}129_{, N. Kanaya}156_,

M. Kaneda30_{, S. Kaneti}28_{, V.A. Kantserov}97_{, J. Kanzaki}65_{, B. Kaplan}109_{, A. Kapliy}31_{, D. Kar}53_{, K. Karakostas}10_,

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. Kerˇsevan}74_{, S. Kersten}176_{, K. Kessoku}156_{, J. Keung}159_{, F. Khalil-zada}11_{, H. Khandanyan}147a,147b_,

A. Khanov113_{, A. Khodinov}97_{, A. Khomich}58a_{, T.J. Khoo}28_{, G. Khoriauli}21_{, A. Khoroshilov}176_{, V. Khovanskiy}96_,

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. Klimentov}25_{, R. Klingenberg}43_{, J.A. Klinger}83_{, T. Klioutchnikova}30_{, P.F. Klok}105_,

E.-E. Kluge58a_{, P. Kluit}106_{, S. Kluth}100_{, E. Kneringer}61_{, E.B.F.G. Knoops}84_{, A. Knue}53_{, D. Kobayashi}158_,

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. Kordas}155_{, A. Korn}77_{, A.A. Korol}108,t_{, I. Korolkov}12_{, E.V. Korolkova}140_{, V.A. Korotkov}129_,

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. Kroll}121_{, J. Kroseberg}21_{, J. Krstic}13a_{, U. Kruchonak}64_{, H. Kr¨uger}21_{, T. Kruker}17_{, N. Krumnack}63_,

Z.V. Krumshteyn64_{, A. Kruse}174_{, M.C. Kruse}45_{, M. Kruskal}22_{, T. Kubota}87_{, S. Kuday}4a_{, S. Kuehn}48_{, A. Kugel}58c_,

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. Lacuesta}168_{, E. Ladygin}64_{, R. Lafaye}5_{, B. Laforge}79_{, T. Lagouri}177_{, S. Lai}48_{, H. Laier}58a_,

L. Lambourne77_{, S. Lammers}60_{, C.L. Lampen}7_{, W. Lampl}7_{, E. Lan¸con}137_{, U. Landgraf}48_{, M.P.J. Landon}75_,

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. Leight}29_{, A. Leisos}155_{, A.G. Leister}177_{, M.A.L. Leite}24d_{, R. Leitner}128_{, D. Lellouch}173_{, B. Lemmer}54_,

K.J.C. Leney77_{, T. Lenz}106_{, G. Lenzen}176_{, B. Lenzi}30_{, R. Leone}7_{, S. Leone}123a,123b_{, K. Leonhardt}44_,

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. Levinson173, M. Levy18, A. Lewis119, G.H. Lewis109, A.M. Leyko21, M. Leyton41, B. Li33b,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. Liebal}21_{, W. Liebig}14_{, C. Limbach}21_{, A. Limosani}87_{, S.C. Lin}152,w_{, T.H. Lin}82_{, F. Linde}106_,

B.E. Lindquist149_{, J.T. Linnemann}89_{, E. Lipeles}121_{, A. Lipniacka}14_{, M. Lisovyi}42_{, T.M. Liss}166_{, D. Lissauer}25_,

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_,