multi-higgs boson production and higgs couplings to the sm · sppc). a new quest to the mystery...

Multi-HiggsbosonproductionandHiggscouplingstotheSM

晏启树,UCASIncollaborationwith

KilianWolfgang,SichunSun,XiaoranZhao,ZhijieZhao,粒⼦物理前沿问题研讨会(⼲州),21－25/January/2019

Outline

• Introduction• EWHiggsinteractionsintheEFT• PerturbativeUnitarityconstraint• VBFHiggsbosonsproductionintheEFT• Conclusion

arXiv:1808.05534

ThoseweknowaboutHiggsBoson

Production,decay,quantumcorrections,…AgreementwiththeSM,but…

Thosewedonotknowuptonow

QuestionstotheHiggsboson

• What’stheoriginofHiggsboson’smass?• Isitcompositeorfundamental?• What’stheshapeofHiggspotential?• HowisEWsymmetrybroken?• WhetherthereisonlyoneHiggsboson?• CanEWbaryongensiswork?• …

Fundamental? Composite?

ToresolvethefinestructureofHiggsboson,moremeasurementsattheLHC,highprecisionandhighenergymachinesareneeded(Higgsfactory,ILC,FCC-ee/pp,CEPC/SPPC).Anewquesttothemysteryjustbegan.

AschematicviewtoEFTwithaHggsboson

SM

AfewTeV

100~200GeV

EFTwithAHiggs

Composite,SUSY,orothers

E

Bottom-upapproachModel-indepdent

Amodelcorrespondstoaspecificcornerofparameterspace

3PerturbativeUnitarityConstraint

4Multi-HiggsbosonfinalstateviaVBFProductions

ModelImplementinWhizard

ModelImplementinMadgraph

AgreementamongWhizard,Madgraph,andVBFNLOischecked.

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ResultsintheSM:gainswithcollisionenergyincrease

WeassumeotherparameterscanbedeterminedtobeclosetothoseoftheSM

[�0.01, 0.01] [�0.01, 0.01]

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we can determine trilinear coupling to [0.9,1.2] at a 100 TeV collider with an integrated luminosity 30/ab, similar to a precision!

that ILC (1 TeV, 4/ab) can achieve Q. Li, Z. Li, QY, X.R. Zhao, PRD92(2015)1,014015, arXiv:1503.07611

[-1.4,8.3]

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[-13,20]

C.Y. Chen,QY, X.R. Zhao, Z.J. Zhao, Y.M. Zhong, PRD93 (2016)1, 013007

EL for GF Processes(up to O(p6))

At leading order

[0.99,1.01] [0.9,1.1][-0.1,0.1]

gg ! hh

W. Kilian, S. Sun, X. Zhao, and Z. Zhao, JHEP1706,145(2017)

Effective Couplings at a 100 TeV collider

Higgs Quartic Couplings at a 100 TeV collider

[-0.8,1.3] [-2.3,1.5] [-13,20]

gg ! hhh

W. Kilian, S. Sun, X. Zhao, and Z. Zhao, JHEP1706,145(2017)

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Conclusion

• EFTisamodelindependentwaytodescribenewphysics.

• EFTwithaHiggsbosoncanserveasausefultooltoexplorethepotentialoftheLHCandfuturecolliders.

• HighenergyhadroncollidersandhighprecisionmachinescanofferusthecapabilitytoaddressthefundamentalquestionsabouttheHiggssectorattheTeVscale.

Backup

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35

F.Bishara,R.Contino,andJ.Rojo,EPJC(2017)77:481

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F.Bishara,R.Contino,andJ.Rojo,EPJC(2017)77:481

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