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X. Higgs Bosonen in Supersymmetrie Standard Modell: 1 komplexes Higgs Duplett (4 Komponenten) 1 Vakuumerwartungswert 174 GeV 3 massive Eichbosonen (W +,

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Presentation on theme: "X. Higgs Bosonen in Supersymmetrie Standard Modell: 1 komplexes Higgs Duplett (4 Komponenten) 1 Vakuumerwartungswert 174 GeV 3 massive Eichbosonen (W +,"— Presentation transcript:

1 X. Higgs Bosonen in Supersymmetrie Standard Modell: 1 komplexes Higgs Duplett (4 Komponenten) 1 Vakuumerwartungswert 174 GeV 3 massive Eichbosonen (W +, W -, Z 0 ) Eine mögliche Anregung übrig: 1 neutrales Higgs Boson h Supersymmetrie 2 komplexe Higgs Dupletts (8 Komponenten) 3 massive Eichbosonen (W +, W -, Z 0 ) 5 mögliche Anregungen übrig: 3 neutrale Higgs Bosonen: h, H, A 2 geladene Higgs Bosonen: H +, H - In niedr. Ordnung 2 Parameter : tan = und m A

2 In mehr Detail (Martin, 7.1.) 2 komplexe Isospindupletts 8 reelle skalare Felder 3 Goldstone Felder (G +, G 0, G - ) verschwinden in massiven W +, Z 0, W - Verbleiben 3 neutrale (h 0, H 0, A 0 ) und 2 geladene (H +, H - ) Higgs Bosonen X.1. Higgs Phänomenologie in Supersymmetrie

3 Minimal Supersymmetry: 3 neutral Higgs Bosons: h, H, A 2 charged Higgs Bosons: H +, H - at tree level, 2 parameters : tan = v 2 /v 1 and m A Stephen Martin, hep-ph/ g MSSM = g SM MSSM on tree level t b/ W/Z h cos/sin-sin/cossin() H sin/sincos/coscos() A cottan -----

4 MSSM at 2-loop level Loop level (constrained MSSM): SUSY breaking parameters, assumed to be unified at some scale : gluino mass and Higgs mass parameter M ğ and SU(2) gaugino mass term unified at M GUT M 2 at M EW sfermion mass terms : common at M EW M susy at M EW sfermion trilinear couplings : common at M EW A at M EW mixing parameter in the stop sector : X t = A t - cot Total: 8 parameters m t =171.4 GeV measured M 2, M susy, M ğ, and X t chosen to define a benchmark scenario tan and m A free to vary (tan[1, 50] and m A[50, 1000]GeV) Higgs Masses A ~ degenerate in mass with h at low masses H and H ± high masses h mass < 130 GeV (all scenarios) S.Heinemeyer in J.Ellis et al CERN-PH-TH/

5 Benchmark scenarios Examples: Description: M. Carena, S. Heinemeyer, C.E.M. Wagner, G. Weigleinhttp://arxiv.org/abs/hep-ph/

6 Features of Large m A and m H : h is SM-like w/ maximal mass g MSSM = g SM H/A/H ± produced via Fermion-couplings! Large enhancement of SUSY-Higgs ~(tan) 2 possible Large tan: b- associated production Small tan: t- associated production Easy pattern for large m A t b/ W/Z h 11 H -cottan 0 A cottan 0

7 Example: Widths and Branching Ratios to From Ph.D. thesis, Jana Schaarschmidt, TU Dresden, 2010 Widths H,A: enhanced by tan h: above m ~ 200 GeV SM-like (narrow) Branching ratios SM: negligible above 160 GeV SUSY: always sizable increasing w/ tan A and H

8 Cross Sections

9 Can we see the additional Higgses? good news: at least one Higgs boson observable for all parameters in all four MSSM benchmark scenarios bad news: significant area where only lightest Higgs boson h is observable e.g. Higgs discovery, ATLAS prel., 300 fb -1 (M. Schumacher, hep-ph/ , ATL-com-phys )

10 X. 2. Search for Neutral Higgs Bosons How to discover?

11 Basic 2 2 diagram Corresponding to b-pdf in Proton Details much more complex Add 2 3, 2 2, and 2 1 w/o double counting Solution: SHERPA MC generator w/ CKKW matching between Matrix Element and Parton Shower contributions Jet fractions agree with analytic calculation (Harlander+Kilgore) Example: full (down-type) leptonic modes b h/H/A b µ + µ - b h/H/A b b + νν - νν Main backgrounds (several 100 pb) tt (b)b µ + ν µ - ν tt (b)b + ν - ν qZ bµ + µ - qZ b Associate A/H production with b-quarks

12 Mass Resolutions µ + µ - : exzellente Massenauflösung ~ 3 GeV h/A/H trotzdem nicht getrennt, aber Breite messbar gröbere Massenauflösung GeV benutzt kolineare Näherung des Tau Zerfalls tanm A =132 GeV tanm A =150 GeV M.Warsinsky, Doktorarbeit Dresden, TeV, 30 fb -1 ~ 2014 / 2015 J.Schaarschmidt, Diplomarbeit Dresden, TeV, 30 fb -1 ~ 2014 / 2015

13 Collinear Approximation

14 Performance (Ph.D. Thesis, Jana Schaarschmidt, 2010)

15 Lepton + Hadrons (ATLAS) Typical signal and background distributions at 14 TeV without b-Jetwith b-Jet

16 Extraction of Z background m shape from data Use Z and Z ee and reweight the lepton signals Just needs reweighting of track momenta e eNeeds also reweighting of *longitudinal* shower shape Very successful results (Jana Schaarschmidt, 2007) Z ee (Kathrin Leonhardt, 2008, Patrick Czodrowski, 2009)

17 Expected sensitivities Estimated reach after 1 fb -1 at 7 TeV (maybe end of 2011?) Discovery reach after 30 fb -1 at 14 TeV (2014/2015?)

18 X.3. Charged H ± Mass and Couplings: m H ± 2 = m A 2 + m W 2 in MSSM w/ negligible radiative corrections No coupling to W, Z Two fermionic couplings dominant: Minimum tb coupling at tan (m t / m b ) 7

19 LEP Limits Direct LEP limits for e + e - H + H - stop at ~m W due to W + W - backgr. MSSM: BR(H ±) dominant for m H ± ~ 85 – 89 GeV LEP direct H ± limits: Relevant in non-SUSY 2-Higgs Doublet Models (2HDM) Marginal in MSSM, since m H ± 2 = m A 2 + m W 2 anyway

20 Search for Charged Higgs Bosons New input from b-physics!

21 Newly developping constraints from b-decays Gino Isidori, 3 rd Workshop: Flavour in the Era of the LHC, 2006 Well defined pattern for exp. observables Starting to give useful constraints Most limits in literature for 2HDM ! No systematic studies for MSSM yet (too many param.!)

22 Leading-order H ± contribution! 2HDM (W.S.Hou, PRD 48 (1993) 2342) r BBR(2HDM)/BR(SM) = MSSM (G.Isidori, P.Paradisi, hep-ph/ ) Gluino-induced corrections ( (m g,m q ) to down-type Yukawa couplings considerable for large tan r BBR(MSSM)/BR(SM) = B New Physics Amplitude M (H ± ) has opposite sign! suppression | M (H ± )| < | M (W ± )| (near-)cancellation | M (H ± )| ~ | M (W ± )| (near-)compensation | M (H ± )| ~ 2| M (W ± )| enhancement | M (H ± )| > 2| M (W ± )| r B tan ± ± ~~

23 B Experimental Signature

24 B First Observations 2.6 C.Bozzi, HCP2007

25 MSSM interpretation of B- and other constraints G. Isidori, F. Mescia, P. Paradisi, D. Temes: hep-ph/ < R b s < 1.24 (1 sigma): blue lines 0.8 < R B < 0.9 (future guess!): black lines current 1-sigma would be 0.7 < R B < 1.3 NB: 2nd solution for m H < 200GeV not shown! B μ + μ < 8.0 × 10 8 : allowed below green line m B s = ± 0.25 ps 1 : allowed below gray line (g-2) μ : 2 < a μ (exp SM)/10 9 < 4 : purple lines Dark Matter (~Bino) density: light blue forbidden M ˜q = 1.5 TeV A U = 1 TeV μ = 1.0 TeV M ˜ = 0.4 TeV M ˜q = 1.5 TeV A U = 1 TeV μ = 0.5 TeV M ˜ = 0.3 TeV

26 Two main production processes for m H ± < m t gg t t bW bH ± for m H ± > m t bg tH ± bW H ± Two main decay modes H ± dominant for small m H ± below 200 GeV (large tan 10) below 150 GeV (small tan ) H ± tb, approaches for large tan BR(tb)/BR() = (m b /m ) 2 ~ 6 H ± at LHC H±H± ± m H ±(GeV) H ± (fb) M. Schumacher, ATL-com-phys H±H± t

27 z.B. für m H ± > m t : tH ± bW Transversale Massenverteilung nach 30 fb -1 Entdeckungs und Ausschlusspotenzial (Alle Kanäle kombiniert) H ± Discovery reach (ATLAS, TDR 2008) ~


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