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Beyond the Standard Model

Beyond the Standard Model. Searches for New Physics at the B-Factories. Where to look for New Physics?. Experimental Strategies. W + ,. W + ,. W + ,. W + ,. H +. H +. H +. H +. b → sg penguins. g. s,u. b → s g penguins. B,D → X us ll ,X us nn. Z,. h 0. l , n. u. l , n.

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Beyond the Standard Model

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  1. Beyond the Standard Model Searches for New Physics at the B-Factories K. Honscheid Ohio State University Aspen 2006

  2. Where to look for New Physics? K. Honscheid, Ohio State University, Aspen 2006

  3. Experimental Strategies W+, W+, W+, W+, H+ H+ H+ H+ b→sg penguins g s,u b→sg penguins B,D →Xusll,Xusnn Z, h0 l,n u l, n l, n l,n l ~ LFV n t t t→lg ~ c g n Surprises B,D →ll,nn B→tn From Hitlin, LHC Lavor Workshop K. Honscheid, Ohio State University, Aspen 2006

  4. Experimental Landscape (ca 2006) Integrated Luminosity 550 fb-1 320 fb-1 Belle BaBar Million t Leptons Million D Mesons Million B Mesons CLEO II.5 CLEO II K. Honscheid, Ohio State University, Aspen 2006

  5. Search for Lepton Flavor Violation in t Decays l • Lepton flavor is conserved in the Standard Model • not protected by an underlyingconserved current symmetry • Neutrino Masses • Many SM extensions include LF violation • Observation of LF violation would be a clear signature for new physics ~ n t ~ c g K. Honscheid, Ohio State University, Aspen 2006

  6. Search for t-→ e-g PRL 96, 041801 (2006) n ttag Positrons Electrons tsignal e g • 207106 e+e- → t+t- events • Observe 1 event in a 2s2s signal box on 1.9±0.4 expected background • Previous limits (all @ 90% CL): • Br(t- → m-g) < 0.68  10-7 (BaBar, PRL 95 041802) • Br(t- → m-g) < 3.1  10-7 (Belle, PRL 92 171802) • Br(t- → e-g) < 3.8  10-7 (Belle, PLB 613 22) Br(t-→ e-g) < 1.1  10-7 at 90% C.L. K. Honscheid, Ohio State University, Aspen 2006

  7. Limits on New Physics – An Example tlg and mSUGRA Just an example with tanb=55 Trilinear coupling A0=0 Inverted mn hierarchy … Excluded by LEP s-t is LSP Excluded by WCDM allowed Br(teg)<1x10-8 2x10-8 5x10-8 11x10-8 Current BaBar limit O. Igonkina, SUSY 2005 K. Honscheid, Ohio State University, Aspen 2006

  8. Search for New Physics in the Charm Sector • D0 MixingFlavor eigenstates are not mass eigenstates with M1,2 and G1,2 • D0 Mixing is small in the SM box diagram: x,y, < few x 10-5 long distance: x ~ 10-3, y ~ 10-2 • Strong phase in hadronic decaysx’ = x cosd + y sindy’ = y cosd – x sind • Proper Time Fit Using D0 K+p-, 400 fb-1 Wrong sign hep-ex/0601029 K. Honscheid, Ohio State University, Aspen 2006

  9. Experimental Limits on D0 mixing hep-ex/0601029 World 95% CL in (x,y) World 95% CL in y 95% CL Limits (assuming CP) x’2 < 0.72 x 10-3 -9.9 x 10-3 < y’ < 6.8 x 10-3 Note: No-Mixing (0,0) has only 3.9% CL G. Burdman and I. Shipsey, Ann. Rev. Nucl. Part. Sci. 53, 431 (2003) [arXiv:hep-ph/030076] (assuming d = 0, CPV = 0) K. Honscheid, Ohio State University, Aspen 2006

  10. Rare Charm Decays and CP Violation from S. Stone K. Honscheid, Ohio State University, Aspen 2006

  11. Experimental Aside: Single B Meson Beams Lots of interesting modes include one or more neutrinos. “Beams” with a single, monochromatic B and without c, QED etc would be very useful for : Btn, Bnn, BKnn,… Fully reconstruct one of the Bs and study the remaining of the event  closed kinematics, missing energy reconstruction Tag types Semileptonic D(*)l(np) 5K/fb-1 Hadronic D(*) X 3K/fb-1 purity efficiency X=np+mp0+pK+qKs K. Honscheid, Ohio State University, Aspen 2006

  12. Search for Btn hep-ex/0507069 • SM decay proceeds via W-annihilation diagram • Sensitive to new physics charged current • Analysis: • Undetected neutrinos result in large missing energy and few kinematic constraints – high background. • Reduce the background by reconstructing the second B (“tag B”) in the event in the copious decay mode B-→D*0l-nl • Reconstruct B+→t+ut with t+→l+nnbar or t+→h+n, where h = p, r, or a1 • Require no additional charged tracks in the event K. Honscheid, Ohio State University, Aspen 2006

  13. Results for Btn Expectations from U.T. fit Current BaBar 90% C.L. +e+e BaBar SL tags 230M BB MC Signal for Br=10-3 Energy in addition to signal candidate (GeV) Close to the discovery of this mode or NP No signal in 230 M BB events 90% CL Upper Limit (Combined with hadronic tags) …even closerhep-ex/0507034 New Belle analysis using 250 fb-1 Br(B+→t+ut) < 2.6  10-4 K. Honscheid, Ohio State University, Aspen 2006

  14. Higgs sensitivity 2HDM Gambino, Misiak Nucl. Phys. B611 338 Hou Phys.Rev.D48:2342-2344,1993 Limits on 2-Higgs Models from Btn Current limits mH(GeV) both bsg Btn tanb K. Honscheid, Ohio State University, Aspen 2006

  15. Search for Bs +- at the Tevatron CDF 360 pb-1 300pb-1 hep-ex/0508058 Standard model prediction: Br(Bs+-)= (3.50.9) 10-9 No Signal found Bs+- < 2.010-7CDF Bs+- < 3.910-7D0 Combined (90% CL) Bs+- < 1.510-7 K. Honscheid, Ohio State University, Aspen 2006

  16. EW Penguins:BKl+l-, BK*l+l-, and BXsl+l- • With l+l- pair, can produce both pseudoscalar and vector mesons • SM: Br(B →Kl+l-) ~ 4  10-7(± 30% theory) ~3 times that for K* New Physics affects • Rates • Asymmetries (AFB, CP) • mm/ee ratio Affects Belle prelim. hep-ex/0410006, 0508009 BABAR hep-ex/0507005 (229M BB) K. Honscheid, Ohio State University, Aspen 2006

  17. BKl+l- and BK*l+l- : branching fractions pole at low q2 Theory errors mainly due to form factors. (rarest observed B decay) K. Honscheid, Ohio State University, Aspen 2006

  18. BK*l+l-: Lepton F-B Asymmetry hep-ex/0508009 Lepton angular distribution in l+ l- rest frame 386 M BB SM NP scenarios constraints on Wilson coeffs describing short-distance physics K. Honscheid, Ohio State University, Aspen 2006

  19. Getting Lost? MSSMMFVlarge tanb Little Higgs wMFV UV fix Generic Little Higgs Extra dim wSM on brane Generic extra dim w SM in bulk SUSY GUTs SupersoftSUSY breakingDirac gauginos MSSMMFVsmall tanb Effective SUSY SM-like B physics New Physics in B data after G. Hiller K. Honscheid, Ohio State University, Aspen 2006

  20. Be ready for surprises Y(3940) Z(3930) B decays X(3872) gg B decays BELLE 2003 2004 2005 BaBar DsJ(2458) continuum Y(4260) DsJ(2317) ISR Several new particles have been observed by the B Factories Different production mechanism Different JPC For a nice review by Swanson see hep-ph/0601110 K. Honscheid, Ohio State University, Aspen 2006

  21. CP Violation in the B System Present CKM fit Present WA See talk by Aihara for more on CPV K. Honscheid, Ohio State University, Aspen 2006

  22. Bounds on new physics from UT fits d b b CKM Model confirmed by many measurements Now look for New Physics as correction to CKM Model The fit to the unitarity triangle constraints: cNP W + = = W K. Honscheid, Ohio State University, Aspen 2006

  23. Bounds on new physics from UT fits Constraints: |Vub|, Dmd, SyK add: a, g First constraints on Qd, CBd In terms of probed new physics mass scale (L=m(cNP); gNP=coupling) L(now)~5gNP TeV Ligeti,Silvestrini,Agashe et al K. Honscheid, Ohio State University, Aspen 2006

  24. The next few years (2006 – 2008) Belle and BaBar 1 ab-1 (2006) 2 ab-1 (2008) Tevatron 2 fb-1 (2006) 8 fb-1 (2009) LHCb is nearing completion ICHEP08 See talk by S. Stone on Thursday K. Honscheid, Ohio State University, Aspen 2006

  25. Super B-Factory Plans at KEK and Frascati Design Luminosity ~ 1 x 1036 /cm2/secSynergy with ILCLots of R&D needed New Beam pipe More RF power Interaction Region Crab crossing q=30mrad. by*=3mm New QCS Damping ring Linac upgrade L = 41035/cm2 /sec Frascati KEK Next Super B Workshop in Frascati, March 16-18, 2006 K. Honscheid, Ohio State University, Aspen 2006

  26. Have Ideas – Need Statistics K. Honscheid, Ohio State University, Aspen 2006

  27. Additional Transparencies K. Honscheid Ohio State University Aspen 2006

  28. Let’s rule out at least one NP model Observation of direct CP violation inB0K+p- 232x106 BB’s B0K+ B0K+ New Belle Result: -0.113+/- 0.022+/- 0.008 BaBar 2004 • Superweak Model (Wolfenstein) is really out K. Honscheid, Ohio State University, Aspen 2006

  29. Implications of Bs+-<1.510-7 M0 [GeV] mSUGRA prediction: Dedes, Dreiner, Nierste PRL87:251804,2001 Excluded! K. Honscheid, Ohio State University, Aspen 2006

  30. Search for LFV in t-→ l±hh’ PRL 95, 191801 (2005) hep-ex/0509016 Br(t-→ e-Ks) < 5.6  10-8 at 90% C.L. Br(t-→ m-Ks) < 4.9  10-8 at 90% C.L. K. Honscheid, Ohio State University, Aspen 2006

  31. First Search for B0→t+t- hep-ex/0501115 • SM expectation ~ 10-7(Compare: 10-11 for m+m-, 10-15 for e+e-) • Helicity (ml/mB)2 and Cabibbo (VtbVtd*) suppressed • Very clean theoretically • Small SM Sensitive to new physics in the loops t+ t - t+ t - • Analysis • Reconstruct the tag B in decays to D(*) and up to 5 kaons and pions • Reconstruct the signal decayB0→t+t-, with t→1-prong decays • Require no additional charged tracks in the event • Require little remaining energy: Eextra < 0.11 GeV • Use correlations between Eextra and the momenta of the reconstructed t daughters in a neural net to further reduce the background t+ t - K. Honscheid, Ohio State University, Aspen 2006

  32. B0→t+t- Results hep-ex/0501115 Using 232  106 Y(4S)→BB events we observe263 ± 19 events with 281 ± 40 expected background. First limit on this mode Br(B0→t+t-) < 3.2  10-3 at 90% C.L. GeV Yields a constraint on leptoquark parameter. For example RH coupling to generations i,j Leptoquark doublet mass K. Honscheid, Ohio State University, Aspen 2006

  33. Measurement of B(BXsl+l-) Decay width for bsll (s=q2/mb2 ) Sign of C7 flipped SM hep-ex/0503044 Analysis • Semi-inclusive technique • Xs is reconstructed from K+ or Ks + 0-4p (at most one p0 is allowed) • MXs < 2.0 GeV • Electron or muon pair • Mll>0.2GeV • Charmonium veto 140 fb-1 used Wrong flavor MXs Theoretical prediction by Ali et al. q2 K. Honscheid, Ohio State University, Aspen 2006

  34. Constraints on Ci from B(BXsl+l-) • Clean prediction for B(BXsll) with 1<q2<6GeV2is available. • Combine Belle and Babar results • Sign of C7 flipped case with SM C9 and C10 values is unlikely. P.Gambino, U.Haisch and M.Misiak PRL 94 061803 (2005) Donut : 90% CL allowed region C10NP C10NP C7 = -C7SM C7SM C9NP K. Honscheid, Ohio State University, Aspen 2006

  35. 2005: Sample used for AFB(BK*ll)(q2) hep-ex/0503044 2001: Belle 1st observed Treat q2, cos(θ) dependence of bkgs. Sample for BK* l l events 113±13 BK l l control sample 96±12 Consistent with flat K. Honscheid, Ohio State University, Aspen 2006

  36. New Measurement of AFB(q2) in K*ll • Forward-backward asymmetry is induced by interference btw virtual photon and Z0 contributions. • Relative signs and magnitudes of C7 to C10 and C9 to C10 can be determined from AFB(BK*ll)!! We do not use Ci but Ai which is leading coefficients. K. Honscheid, Ohio State University, Aspen 2006

  37. Fit results for ratios of Wilson coefficients Null test with K+ll Projectionto AFB Best fit for negative A7 (SM like) J/Y Y’ SM Best fit for positive A7 (non-SM like) (This solution is also allowed) K. Honscheid, Ohio State University, Aspen 2006

  38. Confidence Level Contours A10/A7 ＳＭ A9/A7 • For any allowed A7, we obtain 95% CL • Sign of A9A10 is negative!! • Sign of A9A10 flipped case is excluded • The first and third quadrants • Sign of A7A10 is not determined yet. • The second and fourth quadrants SM SM Best fit fit result A7A10 sign flipped (to SM) Both A7A10 and A9A10 signs flipped A9A10 sign flipped K. Honscheid, Ohio State University, Aspen 2006

  39. What is the ultimate possible UT precision? • Theoretical limits (continuum methods) • Many measurements will not be theory-limited for quite some time Ligeti: K. Honscheid, Ohio State University, Aspen 2006

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