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Searches for Non-SM Higgs Bosons at the Tevatron

Searches for Non-SM Higgs Bosons at the Tevatron. Makoto Tomoto (Fermilab) On behalf of the D Ø & CDF Collaborations. Moriond QCD March 16 th , 2005. Outline. SUSY Higgs Bosons Search for h( bb) bb (D Ø) Search for hX  tt X (CDF) Long-Lived Doubly Charged Higgs Bosons (CDF).

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Searches for Non-SM Higgs Bosons at the Tevatron

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  1. Searches for Non-SM Higgs Bosons at the Tevatron Makoto Tomoto (Fermilab) On behalf of the DØ & CDF Collaborations Moriond QCD March 16th, 2005

  2. Outline • SUSY Higgs Bosons • Search for h(bb)bb (DØ) • Search for hX ttX (CDF) • Long-Lived Doubly Charged Higgs Bosons (CDF)

  3. SUSY Higgs • In two Higgs doublet model, such as MSSM • 5 physical Higgs bosons  h, H, A, H+, H- (mh < mH) • tanb = vu/vd : ratio of vacuum expectation value of 2 Higgs • Cross sections for bbh enhanced like tan2b • Tevatron is sensitive to large tanb and mA >~90 GeV • h is predicted to be light (mh < ~135 GeV) • LEP limit is mh> ~92 GeV • At high tan b , A is almost degenerate with h/H • s(A) ~ s(h/H), G(A) ~ G(h/H) • Br(Abb) ~ Br(h/Hbb) ~ 90% • Another 10% is Br(A/h/Htt) • hbb(bbbb) and hXttX are the best channels to search for h/H/A

  4. h(bb)bb Search (DØ) • L=260pb-1 • Trigger : at least 3 jets with ET>15GeV • Selection • Offline selection on leading jets optimized for each Higgs mass • Secondary Vertex b-Tagging • Double b-tag and Triple b-tag • Backgrounds • QCD fake: jjjj … From Data • QCD heavy flavor: bbjj, ccjj, cccc, bbcc, bbbb … From Data • Other: Z(bb,cc), tt … From MC • Simulations • SM Higgs … PYTHIA • s and kinematics adjusted to NLO (P.R.L 94, 031902(2005) Dawson et.al) • Background • PYTHIA,ALPGEN,MADGRAPH Jet Secondary Vertex Lxy/s(Lxy) > 5 Primary vertex

  5. h(bb)bb Search (DØ) • “mis-tag” rate function from full samples (as a function of pT and h) • ~2% • (double b-tag data) x (mis-tag rate) = (triple b-tag backgrounds) • Shape of events with  3 b-jets similar to double b-tag distribution • Their cross sections are very small • Fitting triple b-tag dijet mass distribution outside the signal region x mis-tag Triple b-tag Double b-tag Heavy Flavor MC signal Full data x (mis-tag)2

  6. h(bb)bb Search (DØ) • No evidence and Set Limits on cross section & tanb vs. mA plane • Set limits on tan b vs. mA in two of the “benchmark scenarios” • “No mixing” and “maximal mixing” in the stop sector max-mix : designed to maximize allowed parameter space • Exclude significant portion of tanb down to 50, depending on mA and MSSM scenario No mixing Two benchmark MSSM scenarios s < 70-20 pb @ 95 % C.L for mA = 90-150 GeV • For mA = 120 GeV: • s < 31 pb @ 95% C.L. , tanb < 55 @ 95% C.L. (Max Mixing)

  7. hXttX (CDF) • 200pb-1 sample collected by t triggers (e/m + isolated track) • te/m e/m + nn, th hadrons + n • Selection • lepton pT, Z mass window cut • Isolation on the th • Event Topology using ET, pT(tl), pT(th) • HT = |pT(tl)|+|pT(th)|+ET > 50 GeV • ET, pT(tl), pT(th) correlations mt<1.8GeV 1,3-prong is used

  8. htt (CDF) • Limits on sxBr extracted from likelihood fits of m(l,th,ET) • Signal Acceptance • PYTHIA + TAUOLA • 115GeV < MA < 200 GeV • Effi. ~ 0.8% (teth), ~ 0.6% (tmth) s < 9.8 – 2.6 pb for mA = 125-200 GeV

  9. Doubly-Charged Higgs Boson • Appeared in several extensions to the SM and can be relatively light • Left-Right Symmetric Model • Higgs Triplet • Little Higgs Model • If short lived: • Invariant mass of like sign dilepton DØ (113pb-1) m(HL) > 118 GeV 95% C.L. CDF (240pb-1) m(HL) > 136 GeV 95% C.L. • If long lived (ct > 3m) • Can be measured by two high ionization tracks DELPHI : m(H) > 99.6 GeV @95% C.L. Coupling depends on L/R Handedness

  10. Long-lived H++/H-- Search (CDF) • L~290pb-1 collected by muon trigger • pT(track) > 20 GeV • dE/dx from drift chamber • dE/dx depends on (charge)2 Signal modeled by quadrupling the dE/dx of cosmic muons (~4x15ns) • No Evidence found • Limits on cross section s < 39.7– 32.6 fb @ 95%C.L. for m(H)=90-160GeV • Mass Limits m(HL) > 133 GeV @ 95 C.L. m(HR) > 109 GeV @ 95 C.L. m(H) > 146 GeV @ 95 C.L. 35ns 20GeV Cross Section (pb)

  11. Summary • CDF and DØ searched for several non-SM Higgs bosons based on data of L=200-300pb-1 • h(hbb)bb from DØ • hXttX from CDF • Long-lived double charged Higgs from CDF • No evidence of excess found • Start excluding significant portion of parameter space • New channels and improved results will come • Twice more luminosity available

  12. Backup Slides

  13. Integrated Luminosity Analysis based on L = 200-300 pb-1 2002 2005 2003 2004 hbb analysis htt analysis H analysis

  14. CDF & DØ detector CDF • Tracking System • b-tagging • tau ID • dE/dx for H • Calorimeter • Jet ID • electron ID for tau ID D0 • Muon detector • muon ID for tau ID

  15. MSSM Scenario • No Mixing • Xt = At - mcotb = 0, • Maximal Mising • Xt = 6 x MSUSY , MSUSY = 1 TeV • Super symmetric loop corrections are calculated using CPSuperH s x BRSUSY = 2 x sSM x tan2b/(1+Db)2 x 9 / (9+(1+Db)2) Db is a function of various SM/SUSY parameters Xt, m, Mg, Mq, etc…

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