Measuring the top-higgs coupling

Transcription

1 Measuring he op-higgs coupling GRK Workshop 5, Freudensad Karim El Morabi, Marco Harrendorf, Ulrich Husemann, Paricia Lobelle, Hannes Mildner, Tobias Pfozer, Mahias Schröder, Shawn Williamson Sepember, 5 INSTITUT FÜR EXPERIMENTELLE KERNPHYSIK (IEKP) KIT Universiä des Landes Baden-Würemberg und naionales Forschungszenrum in der Helmholz-Gemeinschaf

2 Ouline Hannes Mildner Measuring he -coupling Sepember, 5 /8

3 The op-higgs coupling Top-Higgs Yukawa coupling in SM L = m v Srong compared o oher Yukawa couplings special? Hannes Mildner Measuring he -coupling Sepember, 5 /8

4 The op-higgs coupling Top-Higgs Yukawa coupling in SM L = m v Srong compared o oher Yukawa couplings special? Allow arbirary srengh κ, mixure of scalar and pseudo scalar coupling ζ Scalar and pseudo scalar coupling L = m v κ (cos(ζ ) + i sin(ζ ) γ5 )H Moivaion for mixure So far no excluded from Higgs measuremens Mixure possible in some models, e.g., HDM CP-violaion Hannes Mildner Measuring he -coupling Sepember, 5 /8

5 Dependence of Higgs cross secions and branching raios on -coupling Top-Higgs coupling conribues o differen Higgs producion and decay modes Dominan conribuion o gg H H γγ: inerference wih W-loop Also responsible for -producion Hannes Mildner Measuring he -coupling Sepember, 5 4/8

6 Dependence of Higgs cross secions and branching raios on -coupling Top-Higgs coupling conribues o differen Higgs producion and decay modes Dominan conribuion o gg H H γγ: inerference wih W-loop Also responsible for -producion b - κ ζ privae work SM a σ gg H /σ SM gg H σ gg H : larger for pseudo scalar coupling Formula from J. Brod, U. Haisch and J. Zupan, JHEP () 8 Hannes Mildner Measuring he -coupling Sepember, 5 4/8

7 Dependence of Higgs cross secions and branching raios on -coupling Top-Higgs coupling conribues o differen Higgs producion and decay modes Dominan conribuion o gg H H γγ: inerference wih W-loop Also responsible for -producion b - κ ζ privae work SM a /σ SM H σ σ gg H : larger for pseudo scalar coupling σ : larger for scalar coupling Formula from J. Brod, U. Haisch and J. Zupan, JHEP () 8 wih MG5_aMC and Higgs Characerizaion Model (P. Aroisene e al., JHEP () 4) Hannes Mildner Measuring he -coupling Sepember, 5 4/8

8 Dependence of Higgs cross secions and branching raios on -coupling Top-Higgs coupling conribues o differen Higgs producion and decay modes Dominan conribuion o gg H H γγ: inerference wih W-loop Also responsible for -producion b - κ ζ privae work SM a SM Γ H γγ /Γ H γγ σ gg H : larger for pseudo scalar coupling σ : larger for scalar coupling Γ H γγ : inerference effecs visible Formula from J. Brod, U. Haisch and J. Zupan, JHEP () 8 wih MG5_aMC and Higgs Characerizaion Model (P. Aroisene e al., JHEP () 4) Hannes Mildner Measuring he -coupling Sepember, 5 4/8

9 Indirec consrains of coupling From measuremens µ Exp and heory expecaion µ heo (κ, ζ ) for signal srenghs consrains on ζ and κ can be calculaed Calculaion of coupling consrains Using resuls from ATLAS and CMS sored in HiggsSignals daa base Consrucing covariance marix C(κ, ζ ) wih uncerainies of measuremens and correlaed heory uncerainies Comparing measuremens and expecaion µ i = µ exp i Minimizing χ (κ, ζ ) = µ C µ µ heo i (κ, ζ ) P. Bechle, S. Heinemeyer, O. Sal, T. Sefaniak and G. Weiglein, Eur. Phys. J. C 74 (4), 7 Hannes Mildner Measuring he -coupling Sepember, 5 5/8

10 Indirec consrains b χ (non-γ γ Measuremens) Resuls from inerpreing differen ATLAS and CMS measuremens Measuremens wih gg H enough o consrain κ privae work public LHC resuls Hannes Mildner Measuring he -coupling SM //-σ conours - - a Sepember, 5 6/8

11 Indirec consrains b χ (non-γ γ Measuremens) Resuls from inerpreing differen ATLAS and CMS measuremens Measuremens wih gg H enough o consrain κ H γγ imporan for sign of a privae work public LHC resuls SM //-σ conours - - a b χ (non- Measuremens) privae work public LHC resuls SM //-σ conours - Hannes Mildner Measuring he -coupling - a Sepember, 5 6/8

12 Indirec consrains b χ (non-γ γ Measuremens) Resuls from inerpreing differen ATLAS and CMS measuremens Measuremens wih gg H enough o consrain κ H γγ imporan for sign of a helps o consrain allowed region furher - - SM //-σ conours - privae work public LHC resuls a χ (all Measuremens) privae work public LHC resuls b b - χ (non- Measuremens) privae work public LHC resuls SM //-σ conours - - Hannes Mildner Measuring he -coupling a SM //-σ conours - - a Sepember, 5 6/8

13 Limiaions Showed igh consrains on coupling However, model no oo realisic κ and ζ only free parameers New paricles could conribue in loops Need way o measure coupling direcly Hannes Mildner Measuring he -coupling Sepember, 5 7/8

14 producion H -Producion Allows for more model-independen measuremen of op-higgs coupling Three heavy paricles in final sae Hannes Mildner Measuring he -coupling Sepember, 5 8/8

15 producion H -Producion Allows for more model-independen measuremen of op-higgs coupling Three heavy paricles in final sae σ(pp H+X) [pb] pp H (NNLO+NNLL QCD + NLO EW) pp qqh (NNLO QCD + NLO EW) LHC HIGGS XS WG pp WH (NNLO QCD + NLO EW) pp ZH (NNLO QCD + NLO EW) pp (NLO QCD) s [TeV] Small cross secion ( 8 TeV, 5 TeV) Hannes Mildner Measuring he -coupling Sepember, 5 8/8

16 σ(pp H+X) [pb] producion pp H (NNLO+NNLL QCD + NLO EW) pp qqh (NNLO QCD + NLO EW) pp WH (NNLO QCD + NLO EW) pp ZH (NNLO QCD + NLO EW) pp (NLO QCD) W +?? b? H? b? W? s [TeV] LHC HIGGS XS WG Higgs BR + Toal Uncer ττ cc -Producion µµ bb γγ Allows for more model-independen measuremen of op-higgs coupling Three heavy paricles in final sae gg M H [GeV] Zγ WW ZZ LHC HIGGS XS WG Top Pair Decay Channels e µ τ ud cs W decay elecron+jes muon+jes au+jes eτ µτ ττ eµ µµ µτ ee e + eµ eτ dilepons µ + τ + all-hadronic au+jes muon+jes elecron+jes ud cs Small cross secion ( 8 TeV, 5 TeV) Many possible decays of 5 GeV Higgs boson W s can decay hadronically or leponically Hannes Mildner Measuring he -coupling Sepember, 5 8/8

17 CMS resuls on W +?? b? CMS run I resuls H? b? W? γγ bb τ h τ h CMS JHEP 9 (4) 87 s = 7 TeV, fb ; s = 8 TeV, fb Many of he possible final saes are analyzed a CMS Mos imporan ones H bb H γγ Evens wih same sign lepons 4l l Same-Sign l Combinaion Bes fi σ/σ SM a m H = 5.6 GeV µ H(5) = σ /σ SM = Excess of µ ± µ ± + X evens Hannes Mildner Measuring he -coupling Sepember, 5 9/8

18 KIT analysis W +?? b? H? b? W? Our KIT group is mosly working in he lepon + jes channel Hannes Mildner Measuring he -coupling Sepember, 5 /8

19 KIT analysis H W W + q q b b b b ν l Our KIT group is mosly working in he lepon + jes channel Lepon + Jes Channel Higgs o bb: high branching raio Lepon needed for rigger and suppression of QCD-mulije evens Four b-jes and wo ligh jes expeced Hannes Mildner Measuring he -coupling Sepember, 5 /8

20 KIT analysis Toal Inegraed Luminosiy (pb ) Preliminary Offline Luminosiy Jun 4 Jun 8 Jul Daa included from :4 o : UTC LHC Delivered: 98.5 pb CMS Recorded: 9.8 pb Jul 5 Aug H W W + CMS Inegraed Luminosiy, pp, 5, p s = TeV 9 Aug Dae (UTC) Sep 6 Sep q q b b b b ν l Our KIT group is mosly working in he lepon + jes channel Lepon + Jes Channel Higgs o bb: high branching raio Lepon needed for rigger and suppression of QCD-mulije evens Four b-jes and wo ligh jes expeced Currenly preparing analysis of TeV daa Expecing fb his year unforunaely no enough o see more han in run I Hannes Mildner Measuring he -coupling Sepember, 5 /8

21 Analysis sraegy Selecion isolaed lepon A leas 4 jes and b-ags Mosly +jes background lef Caegorizaion Spli according o je- and b-ag mulipliciies Differen background composiion in caegories Differen opologies differen discriminaing variables Mulivariae analysis 4 Fi Train a BDT in all caegories Separaes signal from background Build signal and background model Fi BDT-oupu wih boh: wha fis beer? Hannes Mildner Measuring he -coupling Sepember, 5 /8

22 Caegories -background composiion in caegories More jes/ags larger signal and plus heavy flavor fracion Differen caegories help consraining differen backgrounds Evens / TeV 6 jes, TeV Evens / fb 4 4 jes, TeV Evens / fb 5 jes, TeV Evens / fb +b +b +cc 6 jes, TeV +b +b +cc 4 4 jes, 4 TeV +b +b +cc 5 jes, 4 TeV +b +b +cc 6 jes, 4 ags Evens / fb +b +b +cc Evens / fb 5 +b +b +cc Evens / fb +b +b +cc Hannes Mildner Measuring he -coupling Sepember, 5 /8

23 Discriminaing variables Discriminaing variables are idenified in each caegory Hannes Mildner Measuring he -coupling Sepember, 5 /8

24 Discriminaing variables Discriminaing variables are idenified in each caegory b-agging variables Normalized. CMS privae work Third highes b-ag discriminaor (4 jes, ags) Hannes Mildner Measuring he -coupling Sepember, 5 /8

25 Discriminaing variables Discriminaing variables are idenified in each caegory b-agging variables Even shape / kinemaic Normalized. CMS privae work Third highes b-ag discriminaor (4 jes, ags) Normalized.. CMS privae work Avg. η-φ disance of agged jes (4 jes, ags) Hannes Mildner Measuring he -coupling Sepember, 5 /8

26 Discriminaing variables Discriminaing variables are idenified in each caegory b-agging variables Even shape / kinemaic Normalized. CMS privae work.5. Invarian masses Third highes b-ag discriminaor (4 jes, ags) Normalized.. CMS privae work Normalized.. CMS privae work Avg. η-φ disance of agged jes (4 jes, ags) Hadr. op cand. mass [GeV/c ] (4 jes, ags) Hannes Mildner Measuring he -coupling Sepember, 5 /8

27 Discriminaing variables Discriminaing variables are idenified in each caegory b-agging variables Even shape / kinemaic Normalized. CMS privae work.5. Invarian masses More complicaed variables Third highes b-ag discriminaor (4 jes, ags) Normalized.. CMS privae work Normalized.. CMS privae work Avg. η-φ disance of agged jes (4 jes, ags) Hadr. op cand. mass [GeV/c ] (4 jes, ags) Hannes Mildner Measuring he -coupling Sepember, 5 /8

28 /bb likelihood raio bb background differs in g Invarian mass of bb-pair Kinemaics of ops and b s b b g b Normalized o uni area.. bb g g b mass [GeV/c ] m bb Hannes Mildner Measuring he -coupling Sepember, 5 4/8

29 /bb likelihood raio bb background differs in g Invarian mass of bb-pair Kinemaics of ops and b s b b g b Normalized o uni area.. bb g g b mass [GeV/c ] m bb Inerpre jes as quarks, MET as neurino Calculae and bb likelihoods, conaining p / p bb, he probabiliies of he invarian bb mass o come from bb / M / M bb, describing wheher he bb-kinemaics are signal- or background-like Final discriminan is a likelihood raio: p M h /(p bb M bb + p M h ) Hannes Mildner Measuring he -coupling Sepember, 5 4/8

30 /bb likelihood raio p M h /(p bb M bb + p M h ) nice discriminaor for he correc je assignmen Bu: correc assignmen unknown Normalized.8 CMS privae work correc assignmen.6 bb p M / (p bb M bb + p M ) Hannes Mildner Measuring he -coupling Sepember, 5 5/8

31 /bb likelihood raio p M h /(p bb M bb + p M h ) nice discriminaor for he correc je assignmen Bu: correc assignmen unknown Sum up all possible assignmens Assignmens are weighed by probabiliy ha hey are correc p a correc assignmens have W/op resonances Normalized o uni area. reconsr. op. comb. background reconsruced op mass [GeV/c ] Normalized CMS privae work.8 correc assignmen.6 bb Normalized p M / (p bb M bb + p M ) CMS privae work all assignmens bb ( p p M ) / ( p p M + p p M ) a a bb bb a assignm. assignm. assignm. Hannes Mildner Measuring he -coupling Sepember, 5 5/8

32 MVA TeV Evens / fb Creaing BDT discriminan in all caegories Opimizing selecion of BDT parameers and variables used in every caegory Signal (blue line) a higher BDT values, backgrounds a lower values BDT discriminan in 6 je ag bin 5 +cc +b +b TeV Evens / fb 6 4 +cc +b +b TeV Evens / TeV Evens / fb 4 +cc +b +b x +cc +b +b TeV Evens / fb BDT discriminan in 4 je ag bin +cc +b +b TeV Evens / fb BDT discriminan in 5 je ag bin 4 +cc +b +b TeV Evens / fb BDT discriminan in 6 je ag bin 5 +cc +b +b x BDT discriminan in 4 je 4 ag bin BDT discriminan in 5 je 4 ag bin BDT discriminan in 6 je 4 ag bin Hannes Mildner Measuring he -coupling Sepember, 5 6/8

33 Signal TeV Evens / fb 4 +cc +b +b x BDT discriminan in 6 je ag bin Wai for daa Fi daa wih a background and a background + signal model Decide which is more likely signal or limi Hannes Mildner Measuring he -coupling Sepember, 5 7/8

34 Signal TeV Evens / fb 4 +cc +b +b x BDT discriminan in 6 je ag bin Wai for daa Fi daa wih a background and a background + signal model Decide which is more likely signal or limi Calculaed expeced limi a TeV wih very preliminary sysemaics Combinaion wih oher channels will increase sensiiviy 95% CL σ/σ SM 5 CMS privae work Expeced ± σ 4 ± σ Inegraed luminosiy [fb ] Hannes Mildner Measuring he -coupling Sepember, 5 7/8

35 Conclusion and oulook -coupling ineresing Keep an open mind for a coupling ha differs in more han jus srengh κ from SM -coupling can be consrained indirecly Direc measuremen in imporan Complex search for in preparaion Ineresing resuls o be expeced a he end of run II b privae work public LHC resuls - SM χ (all Measuremens) //-σ conours a Normalized.4 CMS privae work all assignmens.. bb -. ( assignm p p M ) / ( p p M + p p M ) a a bb bb a assignm. assignm. 95% CL σ/σ SM CMS privae work 5 Expeced ± σ 4 ± σ Inegraed luminosiy [fb ] Hannes Mildner Measuring he -coupling Sepember, 5 8/8

36 Conclusion and oulook -coupling ineresing Keep an open mind for a coupling ha differs in more han jus srengh κ from SM -coupling can be consrained indirecly Direc measuremen in imporan Complex search for in preparaion Ineresing resuls o be expeced a he end of run II b privae work public LHC resuls - SM χ (all Measuremens) //-σ conours a Normalized.4 CMS privae work all assignmens.. bb - Normalized o uni area Wih enough daa,.6 ζ =.5 ζ =π/8 no only srengh.4 ζ =π/4 bu also srucure ζ =π/8. ζ =π/ of he Top-Higgs. coupling could be. measured in p (Higgs boson) [GeV/c].7 MG5_aMCaNLO T 95% CL σ/σ SM. ( assignm p p M ) / ( p p M + p p M ) a a bb bb a assignm. assignm. CMS privae work 5 Expeced σ Inegraed luminosiy [fb ] ± ± σ Hannes Mildner Measuring he -coupling Sepember, 5 8/8