Constraints on anomalous Higgs boson couplings using production and decay information in the four-lepton final state

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Contents lists available atScienceDirect

Physics

Letters

B

www.elsevier.com/locate/physletb

Constraints

on

anomalous

Higgs

boson

couplings

using

production

and

decay

information

in

the

four-lepton

ﬁnal

state

.

The

CMS

Collaboration

CERN,Switzerland

a

r

t

i

c

l

e

i

n

f

o

a

b

s

t

r

a

c

t

Articlehistory:

Received4July2017

Receivedinrevisedform29September 2017

Accepted10October2017 Availableonline16October2017 Editor:M.Doser

Keywords:

Higgs Exoticspin Anomalouscoupling

AsearchisperformedforanomalousinteractionsoftherecentlydiscoveredHiggsbosonusingmatrix elementtechniqueswiththeinformationfromitsdecaytofourleptonsandfromassociatedHiggsboson productionwith two quark jetsineither vectorbosonfusion orassociated productionwith avector boson.ThedatawererecordedbytheCMSexperimentattheLHCatacenter-of-massenergyof13TeV andcorrespondtoanintegratedluminosityof38.6fb−1.Theyarecombinedwiththedatacollectedat center-of-mass energiesof7 and 8TeV,corresponding to integratedluminosities of5.1and 19.7fb−1, respectively.AllobservationsareconsistentwiththeexpectationsforthestandardmodelHiggsboson.

1. Introduction

Theobservation ofa boson witha mass ofabout 125GeV by theATLASandCMSCollaborations[1–3]isconsistentwiththe pre-dictionofthestandardmodel(SM)Higgs(H)boson[4–10].Ithas beenestablished thatthe spin-parityquantum numbersofthe H bosonare consistentwith JP C

=

0++ [11–18].However, thedata stillleave room foranomalousinteractions orCP violation inthe interactionsoftheH boson.Thekinematicsofleptons(

=

μ

±and e±) from H

→

ZZ

/

Z

γ

∗

/

γ

∗

γ

∗

→

4

decays (through virtual pho-tonsorZ bosons),ofquark jetsproducedin associationwiththe H bosoninvector boson fusion (VBF),and ofthe decaysof Z or W bosons produced in association with H (VH) allow studies of anomalousinteractionsoftheH boson[19–36].

TheCMSCollaborationanalyzedthedatacollectedattheCERN LHCatcenter-of-massenergiesof7and8TeV (Run 1), correspond-ingtointegratedluminositiesof5

.

1 and19

.

7fb−1,measuringthe spin-parity properties of the H boson and searching for anoma-lous HVV couplings using the H boson’s decay modes to two electroweakgauge bosons[13].Thatstudyfocused ontestingfor thepresenceofanomalouseffects inHZZ,HZ

γ

,H

γ γ

,andHWW interactionsunderspin-zero,-one,and-twohypotheses.The spin-onehypotheseswereexcluded atgreaterthan99.999%conﬁdence level(CL)inthe ZZ andWW modes;theywere alsoexcluded via the Landau–Yang theorem [37,38] by the observation of the

γ γ

_E-mail_address:_{cms-publication-committee-chair@cern.ch.}

decay mode with5

.

7

σ

signiﬁcance. The spin-two boson hypoth-esis withgravity-like minimal couplings was excluded at99.87% CL, andnine other possible hypotheses ofspin-two tensor struc-tureofHVV interactionswereexcludedat99%CLorhigher.Given theexclusionofthespin-oneand-twoscenarios,constraintswere setonthecontributionofelevenanomalouscouplingstotheHZZ, HZ

γ

,H

γ γ

,andHWW interactionsunderthehypothesisofa spin-zerostate.Among others,theseresultsconstraineda CP-violation

parameter fa3, the fractional pseudoscalar cross section in the

H

→

ZZ channel,which will be described in more detail in Sec-tion 2. Thepure pseudoscalarhypothesis was excluded at99.98% CL,andthelimit fa3

<

0

.

43 wassetat95%CL.Similarresults,fora

smallernumberofparametersandfewerexotic-spinmodels,were obtainedbyATLAS[17].

Alltheabovestudiesconsideredthedecayofanon-shellH bo-son to two vector bosons. The accumulated data in Run 1 were not suﬃcient forprecision tests ofanomalous interactions in as-sociated production, in off-shell production, or with fermions. Nonetheless, both CMS [14] and ATLAS [18] performed analyses ofanomalousHVV interactionsinVH andVBFproduction, respec-tively. Finally, the CMS experimentsearched for anomalous HVV interactionsinoff-shellproductionoftheH bosoninpp

→

H

→

ZZ with Run 1 data [15]. Further measurements probing the tensor structure of the HVV and Hff interactions can test CP invariance

and,moregenerally,anysmallanomalouscontributions[39]. InthisLetter,theanalysisapproachfollowsourpreviousRun 1 publication [13], expanded in two important ways. Information from the kinematic correlations of quark jets from VBF and VH

https://doi.org/10.1016/j.physletb.2017.10.021

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productionisused together withH

→

ZZ

/

Z

γ

∗

/

γ

∗

γ

∗

→

4

decay informationfortheﬁrsttime,applyingtherelevanttechniques dis-cussedinRef.[33].Moreover,datasetscorrespondingtointegrated luminosities of 2

.

7 and 35

.

9fb−1 collected at a center-of-mass energyof 13TeV inRun 2of the LHCduring 2015and2016, re-spectively,are combinedwiththeRun 1data,increasing thedata sampleofH

→

4

eventsbyapproximatelyafactoroffour.

Inwhat follows,the phenomenology ofanomalousHVV inter-actionsisdiscussedinSection2.TheCMSdetector,reconstruction techniques, and Monte Carlo (MC) simulation are introduced in Section 3. Detailsof the analysisare discussed in Section 4, and resultsarepresentedinSection5.WesummarizeinSection6. 2. Phenomenology of anomalous H boson interactions

WeassumethattheH bosoncouplestotwogaugebosons VV, suchasZZ,Z

γ

,

γ γ

,WW,orgg,whichinturncoupletoquarksor leptons [19–34]. Threegeneral tensorstructuresthat are allowed by Lorentz symmetry are tested. Each term includes a form fac-tor Fi

(

q21

,

q22

)

,whereq1 andq2 arethefour-momenta ofthetwo

difermionstates,suchase+e−and

μ

+

μ

−intheH

→

e+e−

μ

+

μ

−

decay.TheH bosoncouplingtofermionsisassumednottobe me-diatedby a newheavy state V, generating theso-called contact terms[35,36]. We thereforestudythe process H

→

VV

→

4f and the equivalent processes in production, rather than H

→

VV

→

4f or equivalent processes. Nonetheless, those contact terms are equivalent to the anomalous HVV couplings already tested using the f1 and fZγ1 parameters, deﬁned below. It is assumed that

all lepton and quark couplings to vector bosons follow the SM predictions.Relaxing thisrequirementwouldbe equivalent to al-lowingthecontacttermstovarywithﬂavor,whichwouldresultin toomanyunconstrainedparameterstobetestedwiththepresent amountofdata.Onlythe lowestorderoperators, orlowestorder termsinthe

(

q2_j

/

2

)

form-factor expansion,are tested,where

isanenergyscaleofnewphysics.

Anomalousinteractionsofaspin-zeroH bosonwithtwo spin-one gaugebosons VV, suchas ZZ, Z

γ

,

γ γ

, WW,andgg,are pa-rameterizedwithascatteringamplitudethatincludesthreetensor structureswithexpansionofcoeﬃcientsupto

(

q2

_/

2

₎

_:

A

(

HVV

)

∼

aVV₁

+

κ

VV 1 q21

+

κ

2VVq22

VV₁

2

m2_V1

∗_V1

_V2∗

+

aVV₂ fμν∗(1)f∗(2),μν

+

aVV3 f∗( 1) μν

˜

f∗(2),μν

,

(1)

whereqi,

Vi,andmV1 arethe four-momentum,polarization

vec-tor,andpolemassofagaugeboson, f(i)μν

₌

μ

Viqνi

−

Viνq μ i ,

˜

f (i) μν

=

1 2

μνρσ f (i),ρσ _[13,33]_,_and_aVV i and

κ

iVV

/

VV₁

2areparametersto bedeterminedfromdata.

InEq.(1),theonlyleadingtree-levelcontributionsareaZZ₁

=

0 andaWW

1

=

0, andwe assume custodialsymmetry, so that aZZ1

=

aWW

1 .The restofthe couplingsare considered anomalous

contri-butions.TinyanomaloustermsariseintheSMduetoloopeffects, andnew,beyondstandardmodel(BSM)contributionscouldmake themlarger.TheSM valuesofthosecouplingsarenotyet accessi-bleexperimentally.Considerationsofgaugeinvarianceand symme-trybetweentwoidenticalbosonsrequire

κ

ZZ

1

=

κ

ZZ 2

= −

exp

(

i

φ

ZZ 1

)

,

κ

₁γ γ_,₂

=

κ

₁gg_,₂

=

κ

₁Zγ

=

0,and

κ

2Zγ

= −

exp

(

i

φ

Zγ 1

)

, where

φ

VV1 isthe

phaseofthecorrespondingcoupling.TheaZγ₂_,₃ andaγ γ₂_,₃ termswere testedintheRun 1analysis[13],buthavetighterconstraintsfrom on-shellphotonmeasurements inH

→

Z

γ

and

γ γ

.We therefore do not repeat those measurements. The HWW couplings appear inVBFandWH production.We relatethosecouplingstotheHZZ measurementsassumingaWW

i

=

aZZi anddroptheZZ labelsinwhat

follows. Four anomalous couplings are left to be tested: a2, a3,

κ

2

/

21,and

κ

Zγ 2

/

Zγ₁

2

.Thegenericnotationaireferstoallfour

ofthesecouplings,aswellastheSMcouplinga1.

Equation (1) parameterizes both the H

→

VV decay and the productionoftheH bosonviaeitherVBForVH.Allthreeofthese processes,whichareillustratedinFig. 1,areconsidered.Whileq2_i

in the H

→

VV process does not exceed

(

100 GeV

)

2 due to the kinematic bound, inassociated production nosuch bound exists. In thepresentanalysisitis assumedthatthe q2_i rangeisnot re-strictedwithintheallowedphasespace.

The effective fractional cross sections fai and phases

φ

ai are

deﬁnedasfollows:

fai

= |

ai

|

2

σ

i

|

aj

|

2

σ

j

,

and

φ

ai

=

arg

(

ai

/

a1

) .

(2)

This deﬁnition of fai is valid for both the SM coupling a1

and the anomalous couplings, but there is no need for a sepa-rate measurement of fa1 because

fai

=

1. The cross sections

σ

i in Eq. (2) are calculated for each corresponding coupling ai.

They are evaluated for the H

→

ZZ

/

Z

γ

∗

/

γ

∗

γ

∗

→

2e2

μ

process, where ai

=

1 and all other aj

=

0 inEq.(1). Theresulting ratios

are

σ

1

/

σ

3

=

6

.

53,

σ

1

/

σ

2

=

2

.

77,

σ

1

/

σ

1

=

1

.

47

×

104TeV−4,and

σ

1

/

σ

Zγ1

=

5

.

80

×

103TeV−4. Inthe caseofthe HZ

γ

couplingthe

requirement

√

|

q2

i

| ≥

4GeV isintroduced inthe crosssection

cal-culationstoavoidinfrareddivergence.Equation(2)canbeinverted torecoverthecouplingratio,

_aai₁

=

fai fa1

σ

1

σ

i

.

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It is convenient to measure the effective cross-section ratios ( fai) rather than the anomalous couplings themselves (ai). First

of all, most systematic uncertainties cancel in the ratio. More-over, theeffectivefractionsare convenientlyboundedby 0and1 anddonotdependonthenormalizationconventioninthe deﬁni-tionofthecouplings.Untiltheeffectsofinterferencebecome im-portant, the statisticaluncertainties in thesemeasurements scale with the integrated luminosity as 1

/

√

L

, in the same way as cross section measurements. The fai values have a simple

inter-pretation as the fractional size of the BSM contribution for the H

→

ZZ

/

Z

γ

∗

/

γ

∗

γ

∗

→

2e2

μ

decay.Forexample, fai

=

0 indicates

a pure SM Higgs boson, fai

=

1 gives a pure BSM particle, and

fai

=

0

.

5 meansthat the two couplingscontribute equallyto the

H

→

ZZ

/

Z

γ

∗

/

γ

∗

γ

∗

→

2e2

μ

process. Inparticular, fa3 isthe

frac-tionalpseudoscalarcrosssection intheH

→

ZZ

→

2e2

μ

channel. A value 0

<

fa3

<

1 would indicate CP violation, witha possible

mixtureofscalarandpseudoscalarstates,while fa3

=

1 would

in-dicate that the H bosonis apure pseudoscalar resonance,which hasbeenexcludedat99.98%CL[13].

The above approach allows a general test of the kinematic distributions associated with the couplings of H to 4 fermions, whether in the decay or in the associated production channels, as shown in Fig. 1. If deviations from the SM are detected, a moredetailedstudyofthe

(

q2_j

/

2

)

form-factor expansioncan be performed, eventually providing a measurement of the double-differentialcrosssectionforeachtestedtensorstructure.Underthe assumption that thecouplings are constant andreal(i.e.,

φ

ai

=

0

or

π

), the above formulation is equivalent to an effective La-grangian [13]. It is also equivalent to the formulation involving contactterms [35,36]ifthe contacttermsare assumedtosatisfy leptonuniversality.

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Fig. 1. IllustrationofH boson productionanddecayinthreetopologies:gluonfusiongg→H→VV→4(left);vectorbosonfusion qq→VV(qq)→H(qq)→VV(qq) (middle);andassociated production qq→V→VH→ (ff)H→ (ff)VV (right). Inthelattertwocases, althoughthefullH decaychainisnotshowninthefigure,the productionanddecayH→VV maybefollowedbythesamefour-leptondecayshowninthefirstcase.Thefiveanglesshowninblueandtheinvariantmassesofthe twovectorbosonsshowningreenfullycharacterizeeithertheproductionorthedecaychain.TheanglesaredefinedineithertheH orV bosonrestframes[26,33].(For interpretationofthereferencestocolorinthisfigurelegend,thereaderisreferredtothewebversionofthisarticle.)

3. The CMS detector, simulation, and reconstruction

The H

→

4

decays are reconstructed in the CMS detector, which is composed of a silicon pixel and strip tracker, a lead tungstatecrystal electromagneticcalorimeter (ECAL), and a brass andscintillatorhadroncalorimeter,eachcomposedofabarreland twoendcapsections,allwithinasuperconductingsolenoidof6 m internaldiameter,providingamagnetic ﬁeldof3

.

8 T.Outsidethe solenoidarethegas-ionizationdetectorsformuonmeasurements, whichare embedded in thesteelﬂux-return yoke.Extensive for-wardcalorimetrycomplementsthecoverageprovidedby the bar-reland endcap detectors.Events ofinterest are selected using a two-tieredtrigger system. Adetailed description ofthe CMS de-tector, together with a deﬁnition of the coordinate system used andtherelevantkinematicvariables,canbefoundinRef.[40].

AdedicatedMCprogram, JHUGen 7.0.2[26,29,33,41],isusedto simulatetheeffectofanomalouscouplingsinthe productionand decayH

→

ZZ /Z

γ

∗ /

γ

∗

γ

∗

→

4

.Thegluonfusionproductionof anH bosonissimulatedwiththe powheg 2.0[42–44]event gen-eratoratnext-to-leadingorder(NLO)inquantumchromodynamics (QCD).TheassociatedgluonfusionproductionofanH bosonwith two jetsisaffected by anomalous Hgg interactions. Theseeffects aremodeled with JHUGen. Itisalso foundthat theNLO QCD ef-fectsthatarerelevantfortheanalysisofaspin-zerostatearewell describedbyacombinationofleading-order(LO)matrixelements andpartonshowering[33]. FortheSM case, JHUGen simulations atLOinQCDand powheg simulationsatNLOinQCD,withparton showeringappliedin bothcases, areexplicitly compared,andno signiﬁcantdifferencesarefound.Therefore, JHUGen at LOinQCD isadoptedforthesimulationofVBF,VH,andttH productionwith anomalous couplings. The MELA package [2,26,29,33,41] contains alibraryofmatrixelementsfrom JHUGen for theH boson signal and mcfm 7.0[45–47]forthe SMbackground andisusedto ap-plyweightstoeventsinanyMCsampletomodelanyothersetof couplings.

The main background in thisanalysis, qq

→

ZZ

/

Z

γ

∗

→

4

, is estimated from simulation with powheg, with the next-to-NLO (NNLO)K-factor,whichisapproximately1.1atm4

=

125GeV[48],

applied to the NLO cross section. The gg

→

ZZ

/

Z

γ

∗

→

4

back-groundprocessissimulatedwith mcfm 7.0,wheretheHiggsboson productionK-factoratNNLOinQCD,whichisapproximately2.3at

m4

=

125GeV, is applied to the LO cross section [49]. The VBF

and triple-gauge-boson (VVV) backgrounds are estimated at LO with phantom 1.2.8[50].Thepartondistributionfunctions(PDFs) used for all of these samples are NNPDF3.0 [51]. All MC sam-ples are interfaced with pythia 8.212 [52] tune CUETP8M1 [53]

for partonshowering andfurther processed through a dedicated simulationoftheCMSdetectorbasedon Geant4[54].

The selection of the H

→

4

events and associated particles closelyfollowsthemethodsusedintheanalyses ofRun 1[12,13]

and Run 2[48] data. The main triggers for this analysisselect a pair ofleptons passing loose identiﬁcationand isolation require-ments, withpT oftheleading andsubleadingelectron(muon) at least23(17)and12(8) GeV, respectively.Tomaximizethesignal acceptance,triggersrequiringthreeleptons withlower pT thresh-olds and no isolation requirement are also used, as are isolated single-electron and single-muon triggers with higher pT

thresh-olds.Electrons (muons) are reconstructed within thegeometrical acceptance deﬁned by

|

η

|

<

2

.

5

(

2

.

4

)

for transverse momentum

pT

>

7

(

5

)

GeV withan algorithmthatcombinesinformationfrom

theECAL(muonsystem)andthetracker.Itisrequiredthatthe ra-tio of each lepton track’simpact parameterin three dimensions, computedwithrespect to thechosen primary vertexposition, to itsuncertaintybelessthan4.Theprimaryvertexisdefinedasthe vertexwith the highestsumof p2_T of physics objects definedby ajet-findingalgorithm.TodiscriminatepromptleptonsfromZ

/

γ

∗

bosondecaysfromthosearisingfromhadrondecayswithinjets,an isolationrequirementforleptons isimposed.Analgorithmisused to collect the ﬁnal-state radiation (FSR) of leptons. An FSR pho-ton isassociated tothe closestselected leptonin theeventifits angularseparation fromthelepton isbelow therequired thresh-old, asdiscussed in Ref. [48]. Three mutually exclusive channels are considered: H

→

4e, 4

μ

, and2e2

μ

. At leasttwo leptons are requiredtohave pT

>

10GeV,andatleastoneisrequiredtohave

pT

>

20GeV.Allfourpairsofoppositely chargedleptons thatcan bebuiltwiththefourleptons,irrespectiveofﬂavor,arerequiredto satisfym+ −

>

4GeV.TheZ

/

γ

∗candidatesarerequiredtosatisfy

the condition 12GeV

<

m

<

120GeV; the invariant mass of at

leastoneoftheZ

/

γ

∗ candidatesmustbelargerthan40GeV.The four-leptoninvariantmassm4mustbebetween105and140GeV.

Jets are reconstructed using the particle-ﬂow (PF) algorithm

[55], with PF candidates clustered by the anti-kT algorithm [56, 57] with a distance parameter of 0.4, and with the constraint thatthechargedparticlesbe compatiblewiththeprimaryvertex. The jet momentum is determined asthe vectorial sumof all PF candidatemomenta in thejet. Jetsmust satisfy pT

>

30GeV and

|

η

|

<

4

.

7 andbeseparatedfromallselectedleptoncandidatesand any selectedFSR photons by an angular distance

R

(/

γ

,

jet

)

>

0

.

4,wheretheangular distancebetweentwoparticles i and j is

R

(

i

,

j

)

=

√

(

η

i

₋

_η

j

₎

2

_{+ (φ}

i

_{− φ}

j

₎

2_.

(4)

Table 1

Summaryofthethreeproductioncategoriesintheanalysisof2016data.ThediscriminantsDarecalculated fromEqs.(4)and(5),asdiscussedinmoredetailinthetext.Foreachanalysis,theappropriateBSMmodel isconsideredinthedeﬁnitionofthecategories: fa3=1, fa2=1, f1=1,or f

Zγ

1=1.Threeobservables

(abbreviatedasobs.)arelistedforeachanalysisandforeachcategory.Theyaredescribedinmoredetaillater inthetext.

Category VBF-jet VH-jet Untagged

Target qqVV→qqH→ (jj)(4) qq→VH→ (jj)(4) H→4 Selection DVBF 2jetorD VBF,BSM 2jet >0.5 DZH2jetorD ZH,BSM

2jet or not VBF-jet

DWH 2jetorD

WH,BSM

2jet >0.5 not VH-jet

fa3obs. Dbkg,D0VBF−+dec,DVBFCP Dbkg,D0VH−+dec,DCPVH Dbkg,Ddec0−,DdecCP

fa2obs. Dbkg,D0hVBF++dec,DVBFint Dbkg,D0hVH++dec,DintVH Dbkg,Ddec0h+,Dintdec

f1obs. Dbkg,DVBF1+dec,D VBF+dec 0h+ Dbkg,DVH1+dec,D VH+dec 0h+ Dbkg,Ddec1,Ddec0h+ fZγ1obs. Dbkg,D Zγ ,VBF+dec 1 ,D VBF+dec 0h+ Dbkg,D Zγ ,VH+dec 1 ,D VH+dec 0h+ Dbkg,D Zγ ,dec 1 ,D0hdec+ 4. Analysis techniques

Thefullkinematicinformationfromeacheventisextracted us-ingthematrixelementcalculationsinthe mela package.Foreither theH boson decayorassociatedproduction withtwojets, up to sevenkinematicobservables,ﬁveanglesandtwoinvariantmasses, are deﬁned, as shownin Fig. 1 [26,33]. In the 2

→

6 process of associatedH boson productionvia eitherVBF,ZH,orWH and its subsequentdecaytoafour-fermionﬁnalstate, upto13 indepen-dent observables

remain. In the following, we use either the production kinematics, the decay kinematics, or both, as appro-priate. The

pT ofthesystemof theH bosonandtwo jets,which

wouldappearatNLO inQCD,isnotincludedintheinput observ-ables inorder toreduce associated QCD uncertainties. The MELA approach retainsall relevant kinematicinformation ina minimal set ofdiscriminants

D

, computedfrom ratios ofprobabilities

P

. Weusetwotypesofdiscriminants,

D

alt

=

P

sig

P

sig

+

P

alt

(4) and

D

int

=

P

int

P

sig

+

P

alt

,

(5)

where“sig”stands forthe SMsignal;“alt” denotesan alternative hypothesis[29],whichcouldbebackground(“bkg”),analternative H bosonproductionmechanism(“2jet”),oranalternativeH boson couplingmodel(“ai”);and“int”representsthecontributiontothe

probability fromthe interferencebetween“sig”and“alt” [33].By the Neyman–Pearson lemma [58],the

D

alt discriminant contains

all theinformation available fromthe kinematicsto separate the SM signal hypothesis fromthealternative hypothesis.Because all intermediate hypotheses are a linearcombination of the SM hy-pothesis and the alternative hypothesis, the combination of

D

alt

with

D

int also contains all the information available to separate

theinterferencecomponent. Thediscriminantsusedinthis analy-sisaresummarizedinTable 1anddescribedinmoredetailbelow. Theselectedeventsinthe2016datasamplearesplitintothree categories:VBF-jet,VH-jet,anduntagged.TheVBF-jetcategory re-quiresexactlyfourleptonswitheithertwoorthreejetsofwhich atmostone isb quarkﬂavor-tagged, oratleastfourjetsandno b-tagged jets. The VH-jet category requires exactly four leptons

Table 2

ThenumbersofeventsexpectedfortheSM(orfa3=1,inparentheses)fordifferent

signalandbackgroundmodesandthetotalobservednumbersofeventsacrossthe three fa3categoriesin2016and2015data.

VBF-jets VH-jets Untagged 2015 VBF signal 2.4 (1.6) 0.1 (0.1) 2.2 (0.3) 0.4 (0.2) ZH signal 0.1 (0.2) 0.3 (0.5) 0.7 (1.0) 0.1 (0.1) WH signal 0.1 (0.3) 0.3 (1.0) 0.8 (2.2) 0.1 (0.3) gg→H signal 3.2 (3.3) 1.9 (2.0) 49.6 (49.4) 4.6 (4.6) ttH signal 0.1 (0.1) 0.0 (0.0) 0.5 (0.6) 0.1 (0.1) qq→4bkg 0.9 1.1 56.3 5.4 gg→4bkg 0.1 0.1 5.5 0.5 VBF/VVV bkg 0.1 0.0 0.4 0.0 Z+X bkg 3.6 2.0 29.1 1.7 Total expected 10.7 5.8 145.2 12.9 Total observed 11 2 145 11

andtwoormorejets;iftherearefourormorejets,noneofthem shouldbe b tagged.Therequirementsonthenumberofb-tagged jets are applied to reduce cross-feedfrom ttH production. In or-dertoseparatethetargetproductionmodeforeachcategoryfrom gluon fusion production, the requirement

D

2jet

>

0

.

5 is applied

following Eq. (4), where

P

sig corresponds to the signal

probabil-ityforthe VBF(ZH or WH) productionhypothesis intheVBF-jet (VH-jet) category, and

P

alt corresponds to the gluon fusion

pro-ductionoftheH bosoninassociationwithtwojets.Ineachofthe four fai analyses, therequirement

D

2jet

>

0

.

5 istestedwithboth

the fai

=

0 and fai

=

1 signalhypothesesin

P

sig.Thus, this

cate-gorizationdiffersslightlyinthefouranalyses.Thetwohighest pT

jetsareusedinthecalculationofthematrixelements.Allevents not assignedto the VBF-jet or VH-jet categoriesare assigned to the untagged category. The above requirements are summarized in Table 1. Dueto thesmall sizeof the2015data sample, those eventswere not categorizedandwereall treatedasuntagged,as wasdoneintheanalysisof2011and2012data[13].Theexpected andobservednumbersofeventsarelistedinTable 2.

We performan unbinnedextended maximumlikelihoodfit to the eventssplitinto thecategoriesaccordingto thelepton flavor andproductiontopology.Anindependentfitisperformedforeach parameterdefinedinTable 3.Ineachcategoryofevents,three ob-servables

D = {D

bkg

,

D

ai

,

D

int

}

are deﬁnedfollowingEqs.(4)and (5),assummarizedinTable 1.

Theﬁrstobservable,

D

bkg(showninFig. 2(a)),iscommontoall

events andisdesignedto separate the signalfrom thedominant qq

→

4

background,forwhich

P

bkg iscalculated.Thesignaland

(5)

Fig. 2. DistributionsofDbkg(a)foralleventsinRun 2;D0h+ (b),D1 (c),DZγ1 (d),D0−(e),andDCP(h)fortheuntaggedand2015events;D0−intheVBF-jet(f)and VH-jet(g)categories.Thearrowin(a)indicatestherequirementDbkg>0.5,usedtosuppressbackgroundonallotherplots.Pointswitherrorbarsshowdataandhistograms

showexpectationsforbackgroundandsignal,asindicatedinthelegendin(a).ThedashedlinesshowexpectationsforBSMhypotheses,asindicatedintheindividuallegends.

Table 3

Summaryofallowed68% CL(central valueswith uncertainties)and 95% CL(in squarebrackets)intervals onanomalous couplingparametersobtainedfrom the combinedRun 1andRun 2dataanalysis.

Parameter Observed Expected

fa3cos(φa3) 0.00₋+00..2609[−0.38,0.46] 0.000+ 0.010 −0.010[−0.25,0.25] fa2cos(φa2) 0.01₋+00..1202[−0.04,0.43] 0.000+ 0.009 −0.008[−0.06,0.19] f1cos(φ1) 0.02₋+00..0806[−0.49,0.18] 0.000+ 0.003 −0.002[−0.60,0.12] fZγ1cos(φ Zγ 1) 0.26+ 0.30 −0.35[−0.40,0.79] 0.000+ 0.019 −0.022[−0.37,0.71]

backgroundprobabilities includeboth the matrix element proba-bilitybasedonleptonkinematicsandthem4probability

parame-terizationextractedfromsimulationofdetectoreffects.Thesignal

m4parameterizationassumesthatmH

=

125 GeV.

Thesecondobservable,

D

ai,separatestheSMhypothesis fai

=

0

from the alternative hypothesis fai

=

1. It is deﬁned following

Eq.(4),with

P

sig calculated for fai

=

0 and

P

alt forthe

alterna-tive H boson coupling hypothesis with fai

=

1. In the untagged

categorythe probabilitiesare calculated usingonly thedecay in-formation,butintheVBF-jet andVH-jetcategoriesboththe pro-ductionanddecayprobabilitiesareused,withthematrixelements calculatedfor eitherVBF

×

decay or

(

ZH

+

WH

)

×

decay, respec-tively.Thisobservable iscalled

D

0− inthe fa3,

D

0h+ inthe fa2,

D

1 in the f1,and

D

Zγ1 in the f

Zγ

1 analyses [13].Superscripts

areaddedtothediscriminantnametoindicatetheprocessesused tocalculatethematrixelements:eitherdec,VBF

+

dec,orVH

+

dec todenotedecay,VBF

×

decay,or

(

ZH

+

WH

)

×

decay,respectively. Distributionsof

D

0−inthethreecategoriesareshowninFig. 2(e), (f),(g).Fig. 2(b),(c),(d)alsoshowsthedistributionsof

D

0h+,

D

1,

and

D

Zγ₁,respectively,fortheuntaggedevents.

The third observable,

D

int from Eq. (5), separates the

inter-ference ofthe two amplitudescorresponding to theSM coupling andthe alternative H boson coupling model. In the case of the

fa3 analysis, this observable is called

D

CP because if CP is

vio-lateditwouldexhibit a distinctiveforward–backward asymmetry between

D

CP

>

0 and

D

CP

<

0, asillustrated in Fig. 2(h) forthe

untagged category ofevents.In the untagged category, decay in-formation is used in the calculation of

D

int. In the VBF-jet and

VH-jetcategories,productioninformationisused.Asinthecaseof

D

ai, superscriptsindicate whichprocesseswere usedto calculate

thematrixelements.Inthe f1and fZγ1 analyses,theinterference

discriminant doesnot provideadditionalseparation, and

D

0h+ is

usedasthethirdobservable.

Inthelikelihoodﬁt,thesignalprobabilitydensityfunction(pdf) isparameterizedforeachproductionmodeandineachcategoryas

Psig

D

;

fai

, φ

ai

∝

n

ai a1

n

T

n

D

cosn

(φ

ai

) ,

(6)

where

T

n is the three-dimensional template probability obtained

fromMCsimulation,

|

ai

/

a1

|

iscalculatedfrom fai throughEq.(3),

and cos

(φ

ai

)

= ±

1. The sum runs over ﬁve values n

=

0

,

. . . ,

4

in thecase ofVBF and VH,where the HVV coupling appears on boththeproductionanddecaysides,andoverthreecontributions

n

=

0

,

1,and2fortheothersignal modes.Thebackgroundpdf is alsoparameterized withtemplates extractedfromsimulation, ex-ceptforthereduciblebackground,Z

+

X,whichisdominatedbythe Z

+

jets process butalsoincludesthett

+

jets, Z

γ

+

jets,WZ

+

jets, and WW

+

jets processes. The Z

+

X background is estimated us-ing independent control regions indata withloose identiﬁcation requirementsontwoleptons.

The yields of signal events in 2016 data are expressed with two unconstrained parameters

μ

V and

μ

F,which are the ratios

of theobserved yields to theexpectation inthe SM forthe pro-duction mechanisms driven by the HVV couplings (VBF andVH) andfortheother modes(gluonfusion andttH),respectively.The signal yield in 2015 data is expressed with a single parameter

μ

13 TeV, which is a linear combinationof

μ

V and

μ

F. The ﬁt is

alsoperformedsimultaneouslywiththe2011and2012datafrom Ref. [13], where the two signal strength parameters

μ

7 TeV and

μ

8 TeV are alsolinear combinations of

μ

V and

μ

F including the

effectsofthecrosssectionscalingforeachvalueof fai.

Most uncertainties in the signal yields cancel in this analysis because measurements of anomalous couplings are expressed as relative crosssections.Statistical uncertaintiesdominateover any systematicuncertaintiesinthisanalysis.Inthedecay-only observ-ablesthemaineffectscomefromleptonmomentumuncertainties

(6)

Fig. 3. Observed(solid)andexpected(dashed)likelihoodscansof fa3cos(φa3)(a), fa2cos(φa2)(b),f1cos(φ1)(c),and fZγ1cos(φ Zγ

1)(d).ResultsoftheRun 2onlyandthe

combinedRun 1andRun 2analysesareshown.

andarepropagatedinto thetemplateuncertainties asinthe pre-viousanalyses[13],wherethemaineffectisonthem4resolution

affectingthe

D

bkgparameterization.

The primary new feature in this analysis, compared to Run 1[13],is thecategorization based onjets andthe kinematic discriminantsusingjetinformation.Boththeshapesandtheyields arevariedaccordingtouncertaintiesobtainedfromthejetenergy variations.Inaddition,uncertaintiesinrenormalizationand factor-ization scales, PDFs, and the modeling of hadronization and the underlyingeventinMCsimulationarepropagatedtothetemplate andrelativeyield uncertainties.As partofthesestudies, compar-isons were made between QCD production atNLO andLO, with matched pythia hadronizationineach case, forthe VBF, VH,and ttH processes.In all cases, onlysmall differenceswere observed. Theuncertaintiesinthemigrationofsignalandbackgroundevents between categories amount to 3–13% for the signal and 4–25% for the background, depending on the category. Among the sig-nal processes, the largest uncertainties arise fromthe prediction ofthegg

→

H yieldinthe VBF-jetcategory. InttH andgluon fu-sionproduction,anomalous couplings onthe productionside are notgenerallyrelatedtotheHVV anomalous couplingsconsidered here.Thereisanegligibleeffectontheobserveddistributionswith largevariationsinthecouplings.

Backgrounds from the qq

→

4

, gg

→

4

, VBF, and V

+ (

4

)

processes are estimated using MC simulation. Theoretical uncer-tainties in the background estimation include uncertainties from

the renormalizationandfactorizationscales,thePDFs,andthe K-factorsdescribedabove.Anadditional10%uncertaintyisassigned to thegg

→

4

backgroundK-factortocoverpotentialdifferences betweensignalandbackground.

5. Results and discussion

Four fai parameters sensitive to anomalous H boson

interac-tions, as deﬁned in Eqs. (2) and (3), are tested in the observed datausingthepdfinEq.(6).Theresultsofthelikelihoodscansof the fai parameterson13TeV dataonlyandonthefull,combined

datasetfromcollisionsat13,8,and7TeV areshowninFig. 3.The combinedresultsarelistedinTable 3andsupersedeourprevious measurementinRef.[13].

The expected 68% CL constraints improve by nearly an order of magnitude compared to the Run 1 analysis [13], as is evident fromthe narrowminima at fai

=

0 in theexpectationsin Fig. 3.

This effect comes from utilizing productioninformation, because thecrosssectioninVBFandVH productionincreasesquicklywith

faiduetolargerq2valuescontributinginEq.(1) [33].Thenarrow

minima are shallower than expected, which may be understood by examiningthebestﬁtted

(

μ

V

,

μ

F

)

valuesinthefouranalyses

undertheassumptionthat fai

=

0:

(

0

.

76₋+1₀_..10₇₆

,

1

.

08+₋0₀_..21₂₀

)

at fa3

=

0,

(

0

.

01+₋0₀._.89₀₁

,

1

.

24+₋0₀._.20₁₈

)

at fa2

=

0,

(

0

.

20+₋0₀._.94₂₀

,

1

.

20+₋0₀._.21₂₀

)

at f1

=

0, and

(

0

.

24₋+0₀._.84₂₄

,

1

.

20₋+₀0._.20₁₉

)

at fZγ₁

=

0. The values obtainedfor thedifferentanalysesvaryduetothedifferentcategorizationand

(7)

observables.Theoverallbehaviorwith

μ

V lessthan1isconsistent

withadownwardstatisticalﬂuctuationinthesmallnumberofVBF andVH events,withthetotalobservednumberofuntaggedevents similarto theexpectation. Because fewerVBF andVH events are observedthanexpected,thenarrowminimaof

−

2ln

(

L)

at fai

=

0,

whichcomefromtheproductioninformationintheseevents,are observed to be lesspronounced than expected. The minimum is mostpronouncedinthe fa3 analysisinFig. 3(a)duetothelargest

observed

μ

V value.

The improvement in the 95% CL constraints with respect to Run 1ismostlyduetotheincreaseinthenumberofeventswith H

→

4

decayinformationbyaboutafactoroffour.Anotherfactor offourincreaseinthedatasample sizeisexpectedbytheendof 2018,undersimilarrunningconditions.Atthattime,theinclusion ofproductioninformationisexpectedtoresultinimprovementsto the95%CLconstraintsinlinewiththeimprovementsalreadyseen inthe68%CLconstraints.

Other features in Fig. 3 can be explained by examining the kinematicdistributionsinFig. 2.The

D

₀dec₋ distributioninFig. 2(e) favorsa mixture ofthe fa3

=

0 and fa3

=

1 models, resultingin

thebest ﬁt value of fa3

=

0

.

30

±

0

.

21 in Run 2. The

D

decCP

distri-butioninFig. 2(h)hasasmallforward–backwardasymmetry,with more events at

D

dec_CP

>

0 than

D

dec_CP

<

0, which gives preference tothe fa3cos

(φ

a3

)

= +

0

.

30 valueasopposed to

−

0

.

30. The

nar-rowlocalminimumat fa3

=

0 corresponds tothe distributionof

eventsin the taggedcategories in Fig. 2(f), (g), whichfavors the SMhypothesis. TheRun1result[13] favorstheSM strongly, and thereforecombiningthetwodatasetsresultsinaglobalminimum at fa3

=

0.

Certainvalues ofanomalous couplings, such as fa2cos

(φ

a2

)

∼

−

0

.

5 and f1cos

(φ

1

)

∼ +

0

.

5,lead tostronginterferenceeffects

betweentheSM andanomalous amplitudesinEq.(1).Therefore, kinematic distributions of such models are easily distinguished fromSM distributions,andthey areexcludedathighCL inFig. 3. Such anomalous models are shown inFig. 2(b), (c). The fa3

=

1

and fZγ₁

=

1 models are shown in other cases in Fig. 2, as the mostdistinct from SM, except for (h), where maximal forward– backwardasymmetry in

D

CP isshownfor fa3

=

0

.

5.In allcases,

theobserveddistributionsinFig. 2areconsistentwiththeSM ex-pectations.

6. Summary

We studyanomalous interactions ofthe H boson using novel techniqueswithamatrixelementlikelihoodapproachto simulta-neouslyanalyzetheH

→

4

decayandassociatedproductionwith twoquark jets. Three categoriesofeventsare analyzed,targeting eventsproduced in vector boson fusion, withan associated vec-torboson,andingluonfusion, respectively.The datacollectedat a center-of-massenergy of 13TeV in Run 2 of theLHC are com-binedwiththeRun 1data,collected at7and8TeV.Nodeviations fromthe standardmodelare observedandconstraintsare seton thefouranomalousHVV contributions, includingthe CP-violation

parameter fa3,summarizedinTable 3.

Acknowledgements

We thank Markus Schulze for optimizing the JHUGen Monte Carlosimulationprogramandmatrixelementlibraryforthis anal-ysis. We congratulate ourcolleagues in theCERN accelerator de-partmentsfortheexcellentperformanceoftheLHCandthankthe technicalandadministrativestaffs atCERN andatother CMS in-stitutes for their contributions to the success of the CMS effort. Inaddition,wegratefullyacknowledgethecomputingcentersand personneloftheWorldwideLHCComputingGridfordeliveringso

effectivelythe computinginfrastructureessential to ouranalyses. Finally, we acknowledge the enduring support for the construc-tionandoperation oftheLHC andtheCMSdetectorprovidedby thefollowingfundingagencies:BMWFWandFWF(Austria);FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MOST, and NSFC (China); COLCIEN-CIAS(Colombia);MSESandCSF(Croatia);RPF(Cyprus);SENESCYT (Ecuador); MoER, ERC IUT, and ERDF (Estonia); Academy of Fin-land,MEC,andHIP(Finland);CEAandCNRS/IN2P3(France);BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NIH (Hun-gary);DAEandDST(India);IPM(Iran);SFI(Ireland);INFN(Italy); MSIPandNRF(RepublicofKorea);LAS (Lithuania);MOEandUM (Malaysia); BUAP, CINVESTAV,CONACYT, LNS, SEP, andUASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland);FCT(Portugal);JINR(Dubna);MON, RosAtom,RAS,RFBR andRAEP(Russia);MESTD (Serbia);SEIDI,CPAN, PCTIandFEDER (Spain);SwissFundingAgencies(Switzerland);MST(Taipei); ThEP-Center, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey);NASUandSFFR(Ukraine); STFC(United Kingdom);DOE andNSF(USA).

Individuals have received support from the Marie-Curie pro-gramandtheEuropeanResearchCouncilandHorizon2020Grant, contract No. 675440 (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foun-dation;the BelgianFederal Science Policy Office; theFonds pour laFormation à laRecherche dans l’Industrieet dansl’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Sci-ence and Industrial Research, India; the HOMING PLUS program of the Foundation for Polish Science, cofinanced from European Union,Regional Development Fund,the MobilityPlusprogram of theMinistryofScienceandHigherEducation,theNationalScience Center (Poland), contracts Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543, 2014/15/B/ST2/03998, and 2015/19/B/ST2/ 02861,Sonata-bis2012/07/E/ST2/01406;theNationalPriorities Re-search Program by Qatar National Research Fund; the Programa Clarín-COFUNDdelPrincipadode Asturias;theThalisandAristeia programscofinancedbyEU-ESFandtheGreekNSRF;the Rachada-pisekSompotFundforPostdoctoralFellowship,Chulalongkorn Uni-versity and the Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); and the Welch Founda-tion,contractC-1845.

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The CMS Collaboration

A.M. Sirunyan,

A. Tumasyan

YerevanPhysicsInstitute,Yerevan,Armenia

W. Adam,

F. Ambrogi,

E. Asilar,

T. Bergauer,

J. Brandstetter,

E. Brondolin,

M. Dragicevic,

J. Erö,

M. Flechl,

M. Friedl,

R. Frühwirth

1

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V.M. Ghete,

J. Grossmann,

J. Hrubec,

M. Jeitler

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A. König,

N. Krammer,

I. Krätschmer,

D. Liko,

T. Madlener,

I. Mikulec,

E. Pree,

D. Rabady,

N. Rad,

H. Rohringer,

J. Schieck

1

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R. Schöfbeck,

M. Spanring,

D. Spitzbart,

W. Waltenberger,

J. Wittmann,

C.-E. Wulz

1

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M. Zarucki

InstitutfürHochenergiephysik,Wien,Austria

V. Chekhovsky,

V. Mossolov,

J. Suarez Gonzalez

InstituteforNuclearProblems,Minsk,Belarus

E.A. De Wolf,

D. Di Croce,

X. Janssen,

J. Lauwers,

H. Van Haevermaet,

P. Van Mechelen,

N. Van Remortel

UniversiteitAntwerpen,Antwerpen,Belgium

S. Abu Zeid,

F. Blekman,

J. D’Hondt,

I. De Bruyn,

J. De Clercq,

K. Deroover,

G. Flouris,

D. Lontkovskyi,

S. Lowette,

S. Moortgat,

L. Moreels,

Q. Python,

K. Skovpen,

S. Tavernier,

W. Van Doninck,

P. Van Mulders,

I. Van Parijs

VrijeUniversiteitBrussel,Brussel,Belgium

H. Brun,

B. Clerbaux,

G. De Lentdecker,

H. Delannoy,

G. Fasanella,

L. Favart,

R. Goldouzian,

A. Grebenyuk,

G. Karapostoli,

T. Lenzi,

J. Luetic,

T. Maerschalk,

A. Marinov,

A. Randle-conde,

C. Vander Velde,

P. Vanlaer,

D. Vannerom,

R. Yonamine,

F. Zenoni,

F. Zhang

2

UniversitéLibredeBruxelles,Bruxelles,Belgium

A. Cimmino,

T. Cornelis,

D. Dobur,

A. Fagot,

M. Gul,

I. Khvastunov,

D. Poyraz,

C. Roskas,

S. Salva,

M. Tytgat,

W. Verbeke,

N. Zaganidis

GhentUniversity,Ghent,Belgium

H. Bakhshiansohi,

O. Bondu,

S. Brochet,

G. Bruno,

C. Caputo,

A. Caudron,

S. De Visscher,

C. Delaere,

M. Delcourt,

B. Francois,

A. Giammanco,

A. Jafari,

M. Komm,

G. Krintiras,

V. Lemaitre,

A. Magitteri,

A. Mertens,

M. Musich,

K. Piotrzkowski,

L. Quertenmont,

M. Vidal Marono,

S. Wertz

UniversitéCatholiquedeLouvain,Louvain-la-Neuve,Belgium

N. Beliy

UniversitédeMons,Mons,Belgium

W.L. Aldá Júnior,

F.L. Alves,

G.A. Alves,

L. Brito,

M. Correa Martins Junior,

C. Hensel,

A. Moraes,

M.E. Pol,

P. Rebello Teles

CentroBrasileirodePesquisasFisicas,RiodeJaneiro,Brazil

E. Belchior Batista Das Chagas,

W. Carvalho,

J. Chinellato

3

,

A. Custódio,

E.M. Da Costa,

G.G. Da Silveira

4

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(10)

C. Mora Herrera,

L. Mundim,

H. Nogima,

A. Santoro,

A. Sznajder,

E.J. Tonelli Manganote

3

,

F. Torres Da Silva De Araujo,

A. Vilela Pereira

UniversidadedoEstadodoRiodeJaneiro,RiodeJaneiro,Brazil

S. Ahuja

a

,

C.A. Bernardes

a

,

T.R. Fernandez Perez Tomei

a

,

E.M. Gregores

b

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P.G. Mercadante

b

,

S.F. Novaes

a

,

Sandra S. Padula

a

,

D. Romero Abad

b

,

J.C. Ruiz Vargas

a

a_Universidade_Estadual_Paulista,_São_Paulo,_Brazil b_Universidade_Federal_do_ABC,_São_Paulo,_Brazil

A. Aleksandrov,

R. Hadjiiska,

P. Iaydjiev,

M. Misheva,

M. Rodozov,

M. Shopova,

S. Stoykova,

G. Sultanov

InstituteforNuclearResearchandNuclearEnergyofBulgariaAcademyofSciences,Bulgaria

A. Dimitrov,

I. Glushkov,

L. Litov,

B. Pavlov,

P. Petkov

UniversityofSoﬁa,Soﬁa,Bulgaria

W. Fang

5

,

X. Gao

5

BeihangUniversity,Beijing,China

M. Ahmad,

J.G. Bian,

G.M. Chen,

H.S. Chen,

M. Chen,

Y. Chen,

C.H. Jiang,

D. Leggat,

H. Liao,

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F. Romeo,

S.M. Shaheen,

A. Spiezia,

J. Tao,

C. Wang,

Z. Wang,

E. Yazgan,

H. Zhang,

S. Zhang,

J. Zhao

InstituteofHighEnergyPhysics,Beijing,China

Y. Ban,

G. Chen,

Q. Li,

S. Liu,

Y. Mao,

S.J. Qian,

D. Wang,

Z. Xu

StateKeyLaboratoryofNuclearPhysicsandTechnology,PekingUniversity,Beijing,China

C. Avila,

A. Cabrera,

L.F. Chaparro Sierra,

C. Florez,

C.F. González Hernández,

J.D. Ruiz Alvarez

UniversidaddeLosAndes,Bogota,Colombia

B. Courbon,

N. Godinovic,

D. Lelas,

I. Puljak,

P.M. Ribeiro Cipriano,

T. Sculac

UniversityofSplit,FacultyofElectricalEngineering,MechanicalEngineeringandNavalArchitecture,Split,Croatia

Z. Antunovic,

M. Kovac

UniversityofSplit,FacultyofScience,Split,Croatia

V. Brigljevic,

D. Ferencek,

K. Kadija,

B. Mesic,

A. Starodumov

6

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T. Susa

InstituteRudjerBoskovic,Zagreb,Croatia

M.W. Ather,

A. Attikis,

G. Mavromanolakis,

J. Mousa,

C. Nicolaou,

F. Ptochos,

P.A. Razis,

H. Rykaczewski

UniversityofCyprus,Nicosia,Cyprus

M. Finger

7

,

M. Finger Jr.

7

CharlesUniversity,Prague,CzechRepublic

E. Carrera Jarrin

UniversidadSanFranciscodeQuito,Quito,Ecuador

Y. Assran

8

,

9

,

S. Elgammal

9

,

A. Mahrous

10

AcademyofScientiﬁcResearchandTechnologyoftheArabRepublicofEgypt,EgyptianNetworkofHighEnergyPhysics,Cairo,Egypt

R.K. Dewanjee,

M. Kadastik,

L. Perrini,

M. Raidal,

A. Tiko,

C. Veelken

(11)

P. Eerola,

J. Pekkanen,

M. Voutilainen

DepartmentofPhysics,UniversityofHelsinki,Helsinki,Finland

J. Härkönen,

T. Järvinen,

V. Karimäki,

R. Kinnunen,

T. Lampén,

K. Lassila-Perini,

S. Lehti,

T. Lindén,

P. Luukka,

E. Tuominen,

J. Tuominiemi,

E. Tuovinen

HelsinkiInstituteofPhysics,Helsinki,Finland

J. Talvitie,

T. Tuuva

LappeenrantaUniversityofTechnology,Lappeenranta,Finland

M. Besancon,

F. Couderc,

M. Dejardin,

D. Denegri,

J.L. Faure,

F. Ferri,

S. Ganjour,

S. Ghosh,

A. Givernaud,

P. Gras,

G. Hamel de Monchenault,

P. Jarry,

I. Kucher,

E. Locci,

M. Machet,

J. Malcles,

G. Negro,

J. Rander,

A. Rosowsky,

M.Ö. Sahin,

M. Titov

IRFU,CEA,UniversitéParis-Saclay,Gif-sur-Yvette,France

A. Abdulsalam,

I. Antropov,

S. Baﬃoni,

F. Beaudette,

P. Busson,

L. Cadamuro,

C. Charlot,

R. Granier de Cassagnac,

M. Jo,

S. Lisniak,

A. Lobanov,

J. Martin Blanco,

M. Nguyen,

C. Ochando,

G. Ortona,

P. Paganini,

P. Pigard,

S. Regnard,

R. Salerno,

J.B. Sauvan,

Y. Sirois,

A.G. Stahl Leiton,

T. Strebler,

Y. Yilmaz,

A. Zabi,

A. Zghiche

LaboratoireLeprince-Ringuet,Ecolepolytechnique,CNRS/IN2P3,UniversitéParis-Saclay,Palaiseau,France

J.-L. Agram

11

,

J. Andrea,

D. Bloch,

J.-M. Brom,

M. Buttignol,

E.C. Chabert,

N. Chanon,

C. Collard,

E. Conte

11

,

X. Coubez,

J.-C. Fontaine

11

,

D. Gelé,

U. Goerlach,

M. Jansová,

A.-C. Le Bihan,

N. Tonon,

P. Van Hove

UniversitédeStrasbourg,CNRS,IPHCUMR7178,F-67000Strasbourg,France

S. Gadrat

CentredeCalculdel’InstitutNationaldePhysiqueNucleaireetdePhysiquedesParticules,CNRS/IN2P3,Villeurbanne,France

S. Beauceron,

C. Bernet,

G. Boudoul,

R. Chierici,

D. Contardo,

P. Depasse,

H. El Mamouni,

J. Fay,

L. Finco,

S. Gascon,

M. Gouzevitch,

G. Grenier,

B. Ille,

F. Lagarde,

I.B. Laktineh,

M. Lethuillier,

L. Mirabito,

A.L. Pequegnot,

S. Perries,

A. Popov

12

,

V. Sordini,

M. Vander Donckt,

S. Viret

UniversitédeLyon,UniversitéClaudeBernardLyon1,CNRS-IN2P3,InstitutdePhysiqueNucléairedeLyon,Villeurbanne,France