1 / 22

Prospects of Charged Higgs Boson Discovery @ Colliders

Prospects of Charged Higgs Boson Discovery @ Colliders. D. P. Roy Homi Bhabha Centre for Science Education Tata Institute of Fundamental Research Mumbai, India. Outline. Charged Higgs Boson in the MSSM H  Lighter than top(t): t  bH + H  Heavier than top : gbtH - (NLO Cont.)

gad
Download Presentation

Prospects of Charged Higgs Boson Discovery @ Colliders

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Prospects of Charged Higgs Boson Discovery @ Colliders D. P. Roy Homi Bhabha Centre for Science Education Tata Institute of Fundamental Research Mumbai, India

  2. Outline • Charged Higgs Boson in the MSSM • H Lighter than top(t): t  bH+ • H Heavier than top : gbtH- (NLO Cont.) • H± beyond the MSSM : NMSSM & CPVMSSM • SUSY QCD Correction to H± signature

  3. 8 States - 3 Goldstone = 5 Physical St : h0, H0, A0& H± H± carries unambiguous hallmark of MSSM Higgs sector All the MSSM Higgs masses & couplings => MA & tan β

  4. mt > MH± => large tbH+ BR at tan β  1 & tan β  mt/mb LL QCD Corr => mq mq(MH±) => mt =170, mb = 3, mc =1 GeV Pert. Lim. of H±tb coupling => tan β > 1/3 & tan β < 3mt/mb 170 H± decay: tan β < 1 & tan β > 1 (MH± < 140 GeV) H±  cs H±  τν => Deficit in t  bW blν (MH± > 140 GeV) H±  t*bWbb => t bH+ bbbW=> b tag excess Moretti & Stirling; Djouadi, Kalinowski & Zerwas; Ma, Roy & Wudka

  5. MH= 140 GeV tan β ~ 8 problematic Using τ Pol can help to enhance Hτν Sig over W Bg

  6. g t t b H¯ t g t H¯ b g b Production of Heavy H± ( MH > mt ) at LHC LO (Zhu; Plehn et al.) NLO QCD Correction => K  1.5 g t t g (a) t g + t g => 0.8 (0.6) b H¯ b H¯ (b) - overlapping cont. from LO => -0.3 (0) for μF = μR = MH + mt , ( μF = (MH + mt)/5)

  7. Main BRs of H± (MH>200) H± tb dominant at all tanβ Large QCD Bg Signals with 3 & 4 b-tags H± Wh(A) main subdominant at small tanβ ~ 3 (BR 5%) Marginal in MSSM (NMSSM & CPV-MSSM) H± τν main subdominant at large tanβ > 10 (BR~20%) Most promising Signal

  8. g g t t b g Heavy H± (MH>200GeV)Signal at LHC in hadronic τ decay channel Sig has much harder pTτ-jet > 100 GeV(Enhanced byτ pol effect). Azimuthal angle between τ-jet and missing-pT is peaked in backward direction for signal ( forward direction for background). Transverse mass of τ-jet and missing-pT —> MH for Sig (MW for Bg)

  9. τ-Polarization: H  τ (Pτ =+1) gives hard τ-jet from π,ρL, a1L W  τ (Pτ = -1) gives hard τ-jet from ρT , a1T Can be distinguished from X= pπ± / pτ-jet => 90% of 1-pr. hadronic decay V = ρ,a1

  10. Raychaudhuri & Roy Hardness of π± reqd for τ-id => X > 0.3 (low-X peaks of ρL , a1Linaccessible) X > 0.8 cut will retain the high-X ρL & π conts ( Pτ = + Signal), while effectively suppressing the ρT ,a1T conts ( Pτ = – bg ). It will also suppress the fake τ bg from QCD jets effectively.

  11. Guchait, Kinnunen & Roy hep-ph/0608324 PYTHIA+TAUOLA + CMSJET Hardness of π± reqd for τ-id => X > 0.3 X > 0.8 cut retains most of the remaining Signal, while effectively suppressing the Bg.

  12. 3-prong τ-jet without π0 R3 > 0.8 or < 0.4 retains most of the Signal, while suppressing the Bg.

  13. mT > 200 GeV cut effectively suppresses the Bg without affecting the Signal. Provides estimate of H± mass.

  14. H± discovery limit at LHC with luminosity of 30 fb -1 (solid) and 100 fb -1 (dashed lines).

  15. g t t b H¯ Detection of H±  tb Signal at LHC with 3 b-tags :Moretti & Roy 3 pT (b3) > 80 GeV BG large, but 5σ Sig possible at very large (small) tan β

  16. t g t H¯tb3 b g b4 H± tb Signal at LHC with 4 b-tags: Miller, Moretti, Roy& Stirling Eb3> 120 GeV Mbb> 120 GeV cos θbb < 0.75 pT (b4 )>20 GeV Better Sig/Bg at the cost of a smaller Sig size compared to the 3 b-tags

  17. Assamagan, Coadou & Deandrea can fill up intermediate tanβ region for some favorable SUSY parameters Datta, Djouadi, Guchait & Mambrini Viability of H±  tb channel is not supported by the full simulation study:Lowette, D’Hondt &Vanlaer

  18. Extensions of MSSM (NMSSM & CPV-MSSM) Low Tanβ ( < 5 ) region: A not observable at LEP MSSM: Mh > 110 GeV => MA > 160 GeV => MH±> 180 GeV NMSSM: Allows MA1 < 60 GeV with a large doublet component & MH± = 140 - 160 GeV => H± A1W Drees,Guchait & Roy

  19. CPV-MSSM: hA mixing => light H1 with large A comp, MH1< 60 GeV & MH±= 130-150 GeV => H± H1W± t  bH± bH1W bbbW Ghosh, Godbole & Roy

  20. t  bH± bH1W bbbW

  21. t H± b SUSY QCD Correction : Non-decoupling Hall et al., Carena et al., Coarasa et al., Bartl et al. Estimate of Δb at Snowmass points & slopes in mSUGRA, GMSB & AMSB => Δb 20% for tanβ 30 ( ΔKSM~ 20%)Plehn et al.

More Related