Higgs + Jet angular and p T distributions : MSSM versus SM

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1 Higgs + Jet angular and p T distributions : MSSM versus SM Oliver Brein ( Institute for Particle Physics Phenomenology, Durham, UK ) in collaboration with Wolfgang Hollik oliver.brein@durham.ac.uk

2 outline : Higgs + jet in the Standard Model Higgs the LHC Higgs + jet Higgs + jet in the MSSM differences to the SM Feynman graphs MSSM results total hadronic cross LHC ( S = 14TeV) differential hadronic cross section

3 Quickstart LHC/CMS 5σ discovery contours for the MSSM Higgs bosons

4 Higgs the LHC [ Higgs + jet in the SM ] SM Higgs LHC mainly via gluon fusion: g H g Detection (m H GeV): mainly via the rare decay H γγ. difficult! huge background

5 Higgs + jet [R.K. Ellis et al. 87; Baur, Glover 89] (LO) [de Florian, Grazzini, Kunszt 99] (NLO QCD) [ Higgs + jet in the SM ] suggestion: study Higgs events with a high-p T hadronic jet advantage: * richer kinematical structure compared to inclusive Higgs production. better S/B ratio allows for refined cuts 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)

6 [ Higgs + jet in the SM, Higgs + jet ] SM H+jet, partonic processes (mostly loop-induced): gg Hg ( % of total rate) qg Hq, qg H q ( % of total rate) q q Hg (rate small) b b b b b b b b recently simulated: pp H + jet, H γγ [Abdullin et al. 98 & 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 30GeV, η jet 4.5) is a promising alternative (supplement) to the inclusive SM Higgs production for m H GeV.

7 available codes: [ Higgs + jet in the SM, Higgs + jet ] 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 but the LHC calls for further improvement of the theoretical predictions

8 Higgs + jet in the MSSM [OBr, Hollik 03] Motivation: * promising simulation results in the SM case * MSSM prediction for + jet not known yet * process loop-induced potentially large effects from virtual particles differences to the SM partonic processes similar to the SM: but: gluon fusion gg g, quark-gluon scattering q( q)g q( q), q q annihilation q q g * different Higgs Yukawa-couplings g SM q qh = e 2sw mq m g MSSM = e W 2sw q q f ui (α,β)=cos α/sin β change of overall rate f di (α,β)= sin α/cos β mq m W f q (α,β), * additional superpartner-loops (even additional topologies) also angular distribution changed

9 [ Higgs + jet in the MSSM ] Feynman graphs [Field et al. 03; Langenegger et al. 06] (only quark loops) gluon fusion, gg g quark loops g h 0 qi superpartner loops q i s q i s q i s

10 quark-gluon scattering, qg q quark loops [ Higgs + jet in the MSSM, Feynman graphs ] superpartner loops q i s q i s q i s q s g q s g q t q t g q s q s q t q t g q s g q t h0 q s q t g

11 quark-antiquark annihilation, q q g quark loops [ Higgs + jet in the MSSM, Feynman graphs ] superpartner loops ũi s ũ s i ũ s i g ũ s ũ s i ũi s g ũ t g ũ s ũ s ũ s g ũ t g g ũ s ũ s ũ t ũ t ũ t ũ t b b annihilation, b b g b b b b

12 MSSM results total hadronic cross LHC ( S = 14TeV) σ(pp + jet + X) = 1 τ 0 dτ ( dl pp gg dτ ˆσ gg g(ŝ) + q with the parton luminosity dl AB nm dτ = 1 τ dx x 1 1+δnm dl pp qg dτ ˆσ qg q(ŝ) + q dl pp q q dτ ˆσ q q g(ŝ)) [f n/a (x)f m/b ( τx ] ) + f m/a (x)f n/b (τx ). ŝ=τs The cuts p T,jet 30GeV and η jet 4.5 determine τ 0 and the angular integration limits. The results shown are for the MSSM m max h with common squark mass scale M SUSY. benchmark scenario [ partonic processes calculated using FeynArts/FormCalc, see : ]

13 [ MSSM results, total hadronic cross section ] m A - and tan β-dependence (cuts: p T,jet 30GeV, η jet 4.5) SM MSSM, full MSSM, no SP MSSM, no b MSSM, no b, no SP SM MSSM, full MSSM, no SP MSSM, no b MSSM, no b, no SP σ(pp +jet) [pb] M SUSY =400GeV tan β=30 m h -max σ(pp +jet) [pb] 10 m h -max M SUSY =400GeV m A =400GeV m A [GeV] tan β

14 [ MSSM results, total hadronic cross section ] M SUSY -dependence (cuts: p T,jet 30GeV, η jet 4.5) σ(pp +jet) [pb] tan β=6 no-mixing m h -max m A =200GeV 2 no-mixing no-mixing, no SP mh-max mh-max, no SP M SUSY [GeV] σ(pp +jet) [pb] large-µ [X t = 900GeV,m max h tan β=6 m A =200GeV 1 large-mu large-mu, no SP M SUSY [GeV] =124 GeV]

15 relative difference δ = (σ MSSM σ SM )/σ SM ) m h -max scenario, M SUSY =400GeV [ MSSM results, total hadronic cross section ] δ[%] % <δ< 24% 10 tan β m A [GeV]

16 differential hadronic cross section dσ(s, p T ) dp T = 1 dτ dlab nm τ {n,m} 0 dτ dˆσ nm (ŝ = τs, p T ) dp T [ MSSM results ] dσ(s, y lab jet ) dy lab jet with = {n,m} 1 τ 0 dτ 1 τ dx x { fn/a (x)f m/b ( x τ ) dˆσ nm (ŝ = τs, ŷ jet ) 1 + δ nm dŷ jet + f m/a (x)f n/b (τ x ) dˆσ nm (ŝ = τs, ŷ jet ) 1 + δ nm dŷ jet ( ) Y (yjet lab τ x 2, τ, x) = ylab jet + tanh τ + x 2. ŷjet =Y (yjet lab },τ,x) ŷjet = Y (yjet lab,τ,x) Also here, the cuts, p T,jet 30GeV, η jet 4.5 have been applied. Note that the pseudo-rapidity η jet = y lab jet for the massless outgoing parton.

17 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) dσ/dη jet [pb] LHC no-mixing scenario dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]

18 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) dσ/dη jet [pb] LHC m h -max scenario dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]

19 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) dσ/dη jet [pb] LHC large-µ scenario dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]

20 summary SM simulations show: Higgs + high-p T jet production is a promising alternative to the inclusive production. LO MSSM prediction shows large effects due to virtual squarks. (processes loop-induced) sizeable differences between SM and MSSM expectations can occur angular distributions are changed at the 5% level more precise predictions are needed in order to be useful for experimental analyses at the LHC.

21 FORTRAN code HJET to calculate the MSSM (and SM) cross sections, σ total hadronic, dσ hadronic d, dσ hadronic, dσ hadronic, ŝ dp T,jet dy jet d 2 σ hadronic dp T,jet dy jet ˆσ total partonic, dˆσ partonic dω, dˆσ partonic dˆt, dˆσ partonic, dˆσ partonic, dy jet dp T,jet is available on request oliver.brein@durham.ac.uk

22 Backup

23 m A - and tan β-dependence (cuts: p T,jet 30GeV, η jet 4.5) SM MSSM, full MSSM, no SP MSSM, no b MSSM, no b, no SP 100 M SUSY =400GeV m A =100GeV σ(pp +jet) [pb] M SUSY =400GeV tan β=30 m h -max σ(pp +jet) [pb] 10 m h -max SM MSSM, full MSSM, no SP MSSM, no b MSSM, no b, no SP m A [GeV] tan β

24 differential partonic cross sections (cuts: p T,jet 30GeV, η jet 4.5) 0.01 m h -max M SUSY = 400GeV m A = 400GeV tan β = ˆδ = ( dˆσmssm dω dσsm dω )/dσsm dω dˆσ/dω [pb/sr] e-04 ŝ = 300GeV g g SM MSSM q g SM MSSM ˆ g g q g m h -max M SUSY = 400GeV m A = 400GeV tan β = 6 ŝ = 300GeV θ[ ] θ[ ]

25 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) Tevatron no-mixing scenario dσ/dη jet [pb] dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]

26 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) Tevatron m h -max scenario dσ/dη jet [pb] dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]

27 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) Tevatron large-µ scenario dσ/dη jet [pb] dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]

28 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) dσ/dη jet [pb] LHC gluophobic scenario dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]

29 [ MSSM results, differential hadronic c. s. ] p T,jet - and y jet -dependence : (cuts: p T,jet 30GeV, η jet 4.5) dσ/dη jet [pb] LHC small α eff scenario dσ/dp T,jet [pb/gev] e-04 1e η jet m A = 400GeV tan β = 30 1e p T,jet [GeV]