Distributions for Higgs + Jet at Hadron Colliders: MSSM vs SM Oliver Brein Institute for Particle Physics Phenomenology, University of Durham in collaboration with W. Hollik [see also 0705.2744 [hep-ph]; hep-ph/0305321] e-mail: Oliver.Brein@durham.ac.uk
outline : • Higgs + jet in the Standard Model • Higgs + jet in the MSSM • MSSM results
LHC/CMS 5 σ discovery contours for the MSSM Higgs bosons
• Higgs + jet in the Standard Model
• Higgs + jet in the Standard Model – Higgs production @ the LHC SM Higgs production @ LHC mainly via gluon fusion: g H g Detection ( m H ≈ 100 − 140GeV): mainly via the rare decay H → γγ . → difficult ! huge background
[ Higgs + jet in the SM ] – Higgs + jet suggestion: study Higgs events with a high- p T hadronic jet [R.K. Ellis et al. ’87; Baur, Glover ’89] (LO) [de Florian, Grazzini, Kunszt ’99] (NLO QCD) advantage: * richer kinematical structure compared to inclusive Higgs production. → allows for refined cuts → better S/B ratio disadvantage: * lower rate than inclusive Higgs production (*) NLO signal prediction has still sizable theoretical uncertainty ( ≈ 20%) (*) background only partly known at NLO accuracy → theoretical uncertainties larger than in the fully inclusive case (so far)
[ Higgs + jet in the SM, Higgs + jet ] SM H+jet, partonic processes (mostly loop-induced) : • gg → Hg ( ≈ 50 - 70 % of total rate) • qg → Hq, ¯ qg → H ¯ q ( ≈ 30 - 50 % of total rate) b b b b • q ¯ q → Hg (rate small) b b b b recently simulated: pp → H + jet , H → γγ [Abdullin et al. ’98 & ’02; Zmushko ’02] pp → H + jet , H → τ + τ − → l + l − p T / [Mellado et al. ’05] result: H + jet production (e.g. with p T, jet ≥ 30 GeV , | η jet | ≤ 4 . 5) is a promising alternative (supplement) to the inclusive SM Higgs production for m H ≈ 100 − 140GeV.
[ Higgs + jet in the SM, Higgs + jet ] available codes: • Higgsjet [de Florian, Grazzini, Kunszt ’99] NLO QCD cross section for pp → H + jet also: soft gluon resummation [de Florian, Kulesza, Vogelsang ’05] • HqT [Bozzi, Catani, de Florian, Grazzini ’03 & ’06] p T -distribution for pp → H + X at NLL + LO and NNLL + NLO QCD accuracy (large effects at small p T resummed) • MC@NLO [Frixione, Webber ’02; Frixione, Nason, Webber ’05] contains pp → H + X event generation at NLO QCD accuracy • FEHiP [Anastasiou, Melnikov, Petriello ’05] NNLO QCD differential cross section for pp → H + X
• Higgs + jet in the MSSM
• Higgs + jet in the MSSM [OBr, Hollik ’03; ’07] (full MSSM) , [Field, Dawson, Smith ’04] (MSSM, no superpartners) , [Langenegger et al. ’06] (MSSM with soft-gluon resummation, no superpartners) – differences to the SM Motivation: * promising simulation results in the SM case * process loop-induced → potentially large effects from virtual particles partonic processes similar to the SM: gg → h 0 g , gluon fusion q ) g → h 0 q (¯ quark-gluon scattering q (¯ q ), q → h 0 g q ¯ q annihilation q ¯ but: * different Higgs Yukawa-couplings g SM → g MSSM mq mq e e mW − mW f q ( α,β ) , qH = = q ¯ qh 0 2 sw q ¯ 2 sw f uI ( α,β )=cos α/ sin β f dI ( α,β )= − sin α/ cos β → change of overall rate * additional superpartner-loops (even additional topologies) → also angular distribution changed
[ Higgs + jet in the MSSM ] – Feynman graphs gluon fusion, gg → h 0 g quark loops q i q i q i q i g q i q i q i q i q i q i q i q i q i q i q i q i h 0 h 0 q i q i q i q i q i h 0 h 0 h 0 h 0 superpartner loops q s ˜ i q s ˜ i q s ˜ q s q s q s q s q s q s ˜ ˜ ˜ ˜ ˜ q s ˜ ˜ i h 0 i i i i i i q s i ˜ h 0 h 0 i q s ˜ i h 0 q s h 0 ˜ h 0 q s q s i ˜ ˜ i i q s q s ˜ ˜ q s ˜ i i q s i ˜ i q s q s q s ˜ q s ˜ ˜ ˜ q s q s q s q s q s q s q s i i i ˜ ˜ ˜ ˜ ˜ ˜ i ˜ h 0 h 0 q s i i i i i i i ˜ h 0 i q s ˜ i q s q s ˜ ˜ q s q s h 0 ˜ h 0 h 0 ˜ i i i i
[ Higgs + jet in the MSSM, Feynman graphs ] quark gluon scattering, qg → h 0 q quark loops q i q i q i h 0 superpartner loops q s ˜ g ˜ q s q s q s q t ˜ ˜ ˜ q s ˜ ˜ g ˜ h 0 i i i h 0 q t ˜ q s h 0 ˜ h 0 q s i ˜ i q s ˜ ˜ g g ˜ q s q t q t q s q t ˜ ˜ g ˜ ˜ ˜ ˜ h 0 q t q s ˜ h 0 ˜ g h 0 ˜
[ Higgs + jet in the MSSM, Feynman graphs ] q → h 0 g quark anti-quark annihilation, q ¯ quark loops q i q i q i h 0 superpartner loops u s ˜ u s ˜ i u s ˜ u s u t ˜ ˜ ˜ g u t g ˜ i ˜ h 0 i u s ˜ i u s ˜ i u s h 0 h 0 h 0 ˜ u s u s ˜ ˜ g ˜ u s u s g ˜ ˜ g u t g ˜ ˜ ˜ ˜ h 0 u t h 0 u t h 0 u t ˜ ˜ ˜ b -quark processes: bg scattering, bg → h 0 b , b → h 0 g b ¯ b annihilation, b ¯ b b b b [ partonic processes calculated using FeynArts/FormCalc, see : www.feynarts.de ]
• MSSM results
[ MSSM results ] – total cross section total hadronic cross section @ LHC σ ( pp → h 0 + jet + X ) applying the cuts p T, jet ≥ 30 GeV and | η jet | ≤ 4 . 5
[ MSSM results, total cross section ] m A - and tan β -dependence : high m A SM SM MSSM, full MSSM, full MSSM, no SP MSSM, no SP MSSM, no b MSSM, no b MSSM, no b, no SP MSSM, no b, no SP 10 σ ( pp → h 0 +jet) [pb] σ ( pp → h 0 +jet) [pb] 100 m h -max M SUSY =400 GeV tan β =30 m h -max 10 M SUSY =400 GeV m A =400 GeV 90 100 200 300 400 5 10 15 20 25 30 tan β m A [GeV] ⇑ ⇑
[ MSSM results, total cross section ] m A - and tan β -dependence : low m A SM M SUSY =400 GeV MSSM, full MSSM, no SP MSSM, no b m A =100 GeV MSSM, no b, no SP 100 σ ( pp → h 0 +jet) [pb] σ ( pp → h 0 +jet) [pb] 100 m h -max M SUSY =400 GeV tan β =30 m h -max 10 10 SM MSSM, full MSSM, no SP MSSM, no b MSSM, no b, no SP 90 100 200 300 400 5 10 15 20 25 30 m A [GeV] tan β ⇑ ⇑
[ MSSM results, total cross section ] M SUSY -dependence : 12 8 no-mixing 7 10 σ ( pp → h 0 +jet) [pb] σ ( pp → h 0 +jet) [pb] 6 8 5 large- µ [ Xt = − 900 GeV ,m max 6 4 =124 GeV] h m h -max 3 tan β =6 4 tan β =6 2 m A =200 GeV m A =200 GeV 2 no-mixing 1 no-mixing, no SP mh-max large-mu mh-max, no SP large-mu, no SP 0 0 300 400 500 600 700 800 900 1000 400 500 600 700 800 900 1000 M SUSY [GeV] M SUSY [GeV]
[ MSSM results, total cross section ] relative difference δ = ( σ MSSM − σ SM ) /σ SM ) : δ [%] -32 -30 m h -max scenario, M SUSY =400 GeV -28 -26 -24 -22 50 10 − 26% <δ< − 24% tan β 1 200 400 600 800 1000 m A [GeV]
[ MSSM results ] – differential cross section differential hadronic cross sections @ LHC/Tevatron , d 2 σ ( S,p T, jet ,η jet ) dσ ( S,p T, jet ) , dσ ( S,η jet ) dp T, jet dη jet dp T, jet dη jet
[ MSSM results, differential cross section ] p T, jet - and η jet -dependence, low- m A case Tevatron, m h -max scenario, M SUSY = 400 GeV, m A = 110 GeV, tan β = 30 24 35 22 30 20 25 18 20 16 δ [1] δ [1] 15 14 | η jet | ≤ 4 . 5 10 12 5 10 p T, jet ≥ 30 GeV 0 8 6 -5 0.5 10 − 1 all dσ/dp T [pb / GeV] 0.4 10 − 2 dσ/dη 3 [pb] qg 0.3 10 − 3 0.2 10 − 4 q ¯ q 0.1 10 − 5 gg 0 10 − 6 -4 -3 -2 -1 0 1 2 3 4 100 η 3 thick lines: MSSM p T [GeV] thin lines: SM
[ MSSM results, differential cross section ] p T, jet - and η jet -dependence, low- m A case LHC, m h -max scenario, M SUSY = 400 GeV, m A = 110 GeV, tan β = 30 28 40 26 35 24 30 22 25 20 20 δ [1] δ [1] 18 15 | η jet | ≤ 4 . 5 16 10 14 5 p T, jet ≥ 30 GeV 12 0 10 8 -5 40 10 all 35 1 dσ/dp T [pb / GeV] 30 10 − 1 dσ/dη 3 [pb] 25 qg 10 − 2 20 10 − 3 15 10 − 4 q ¯ q 10 5 10 − 5 gg 0 10 − 6 -4 -3 -2 -1 0 1 2 3 4 100 1000 η 3 thick lines: MSSM p T [GeV] thin lines: SM
[ MSSM results, differential cross section ] p T, jet - and η jet -dependence, high- m A case LHC, m h -max scenario, M SUSY = 400 GeV, m A = 400 GeV, tan β = 30 -25 -20 -22 -26 -24 δ [%] δ [%] -26 -27 p T, jet ≥ 30 GeV | η jet | ≤ 4 . 5 -28 -28 -30 1.2 all 10 − 1 dσ/dp T [pb / GeV] 1 10 − 2 dσ/dη 3 [pb] 0.8 10 − 3 gg 0.6 10 − 4 0.4 qg 10 − 5 0.2 q ¯ q 0 10 − 6 -4 -3 -2 -1 0 1 2 3 4 100 1000 η 3 thick lines: MSSM p T [GeV] thin lines: SM
[ MSSM results, differential cross section ] p T, jet - and η jet -dependence, high- m A case LHC, no-mixing(700) scenario, M SUSY = 700 GeV, m A = 500 GeV, tan β = 35 8 18 16 7 14 12 δ [%] δ [%] 6 10 8 5 6 p T, jet ≥ 30 GeV | η jet | ≤ 4 . 5 4 4 2 1.6 10 − 1 1.4 all dσ/dp T [pb / GeV] 1.2 10 − 2 dσ/dη 3 [pb] 1 gg 10 − 3 0.8 0.6 10 − 4 qg 0.4 10 − 5 0.2 q ¯ q 0 10 − 6 -4 -3 -2 -1 0 1 2 3 4 100 1000 η 3 thick lines: MSSM p T [GeV] thin lines: SM
[ MSSM results, differential cross section ] p T, jet - and η jet -dependence, high- m A case LHC, small- α eff scenario, m A = 400 GeV, tan β = 30 -10 0 -5 -11 -10 δ [%] δ [%] -15 -12 -20 p T, jet ≥ 30 GeV | η jet | ≤ 4 . 5 -25 -13 -30 1.2 all 10 − 1 dσ/dp T [pb / GeV] 1 10 − 2 dσ/dη 3 [pb] 0.8 gg 10 − 3 0.6 10 − 4 0.4 qg 10 − 5 0.2 q ¯ q 0 10 − 6 -4 -3 -2 -1 0 1 2 3 4 100 1000 η 3 thick lines: MSSM p T [GeV] thin lines: SM
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