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New Physics and Rare B Decays

New Physics and Rare B Decays. Tom Browder (University of Hawaii). New Physics in Loops (Motivation) b s Penguins (2 or 3 examples) Decays with “Large Missing Energy” How the Super B Factory fits in.

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New Physics and Rare B Decays

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  1. New Physics and Rare B Decays Tom Browder (University of Hawaii) • New Physics in Loops (Motivation) • bs Penguins (2 or 3 examples) • Decays with “Large Missing Energy” • How the Super B Factory fits in Apologies: Will aim at HEP physicists in other subfields. “If I could remember all the decay modes I would have been a botanist” Only a small subset of possible topics from Belle and BaBar are covered; a few of the results are ~ 1year old.

  2. New Physics Are there new particles beyond those in the SM, which have different couplings (either in magnitude or in phase) ? Supersymmety is an example (~40 new phases)

  3. How to find New Physics Phases Example: Vts: no KM phase f1 * Vtd , h’, K+K- , h’, K+K- + B B * Vtd f1 _ SM: sin2f1 =sin2f1 from BJ/y K0(bc c s) unless there are other, non-SM particles in the loop eff

  4. New physics in loops? Many new phases are possible in SUSY How New Physics may enter in bs

  5. Extra dimensions (by Randall + Sundrum) New Kaluza-Klein (K.K) particles are associated with the extra dimension. (“Tower of states”) Some may induce new phases and flavor-changing neutral currents. e.g. G. Burdman, Phys Lett B 590, 86 (2004) e.g. K.Agashe, G. Perez, A. Soni, PRD 71, 016002 (2005) RS1 ++CPV in D decay SM Model: K.K. Gluon near 3 TeV

  6. _ 535M BB Belle 2006: tCPV in B0gfK0 “sin2f1” = +0.50  0.21(stat)  0.06(syst) a.k.a sin(2β) Dt distributions and asymmetry • Consistent with the SM (~1s lower) • Consistent with Belle 2005 (Belle2005: “sin2f1” = +0.440.270.05) • fKS and fKL combined • background subtracted • good tags • Dt g –Dt for fKL unbinned fit SM hep-ex/0608039, PRL 98, 031802(2007)

  7. _ 347M BB BaBar: fK0using B0gK+K-K0 [hep-ex/0607112] b measurement (not sin2b) fK0: sin2beff = +0.12 ± 0.31(stat) ± 0.10 (syst) a.k.a. sin(2 φ1)

  8. 535M BB _ 347M BB 1st Observation of tCPV in a bs mode h’K0 h’Ks h’KL unbinned fit SM 5.6s >5s “sin2f1” = +0.64  0.10  0.04 “sin2f1” = +0.58  0.10  0.03 [hep-ex/0608039]PRL 98,031802(2007) [hep-ex/0607100], PRL+Sept 28 press conf

  9. Smaller than bgccs in all of 9 modes 2006: Hints of NP in bgs Penguins ? Theory predicts positive shifts Naïve average of all b g s modes sin2beff = 0.52 ± 0.05 2.6 s deviation from SM

  10. Results on Radiative and Electroweak Penguins Example discussed here: modifications to the rate for bs γ

  11. Measurement of inclusive b  sg Measure primary g only: monochromatic Eg spectrum Huge Background (semi-log) experimental challenge • Background suppression • continuum: event shape • p0/h veto Important to measure low Eg to reduce model dependence

  12. Nakao

  13. Theory News M. Misiak et al, hep-ph/0609232, PRL 98,022002(2007) NNLO calculation (29826) x 10-6

  14. 95% CL lower limit on charged Higgs mass from exp and NNLO Error on BF Central value of BF M. Misiak et al, hep-ph/0609232, PRL 98,022002 (2007)

  15. mb ms ms mb Right-handed currents in bgsg D.Atwood, M.Gronau, A.Soni, PRL79, 185 (1997) D.Atwood, T.Gershon, M.H, A.Soni, PRD71, 076003 (2005) • tCPV in B0g (Ksp0)K*g • SM: g is polarized, the final state almost flavor-specific. S(Ksp0g) ~ -2ms/mbsin2f1 • mheavy/mb enhancement for right-handed currents in many new physics models e.g. LRSM, SUSY, Randall-Sundrum (warped extra dimension) model • LRSM: SU(2)LSU(2)RU(1) • Right-handed amplitude mt/mb :  is WL-WR mixing parameter • for present exp. bounds ( < 0.003, WR mass > 1.4TeV) |S(Ksp0g)| ~ 0.5 is allowed. • No need for a new CPV phase Photon polarization measurement via time dependent CPV !

  16. 535M BB _ 232M BB Status of B KS 0γ tCPV M(Ks p 0) < 1.8 GeV Yield = 176+/- 18 (-C) hep-ex/0608017, PRD-RC 74, 111014(2006) No new physics but errors on S are large

  17. Rare Decays with Large “Missing Energy”

  18. Motivation for B++ν Sensitivity to new physics from charged Higgs if the B decay constant is known The B meson decay constant, determined by the B wavefunction at the origin

  19. e+ (4S) B- B+ ne n n B-X B++, +e+e Why measuring Bνis non-trivial Most of the sensitivity is from tau modes with 1-prong The experimental signature is rather difficult: B decays to a single charged track + nothing

  20. Example of a B ν candidate Tag: BD0, D0K Very difficult or impossible at a hadron collider

  21. Evidence for B+ν (Belle) BtagD(*)[p,r,a1,Ds(*)] 680k tags, 55% pure. 5 t decay modes 449 106 B pairs Find signal events from a fit to a sample of 54 events. 4.6s stat. significance w/o systematics, After including systematics (dominated by bkg), the significance decreases to 3.5σ MC studies show there is a small peaking bkg in the 0  and   modes. Extra Calorimeter Energy

  22. B+ν (BaBar preliminary) Awaiting BaBar’s analysis with hadronic tags

  23. Direct experimental determination of fB • Product of B meson decay constant fB and CKM matrix element |Vub| • Using |Vub| = (4.39  0.33)×10-3 from HFAG ( Belle) (PRL 97, 251802 (2006)) fB = 216  22 MeV (an unquenched lattice calc.) [HPQCD, Phys. Rev. Lett. 95, 212001 (2005) ] Theory:

  24. Constraints on charged Higgs mass Use known fB and |Vub |Ratio to the SM BF. excluded rH=1.130.51 excluded 449M Compare to direct searches for H+

  25. DAMA NaI 3s Region CDMS 04 CDMS 05 B  K(*)nn : Motivation _ b s with 2 neutrinos SM: B(BK* ) ~1.3 x 10-5 B (BK ) ~4 x 10-6 (Buchalla, Hiller, Isidori) _ _ PRD 63, 014015 • New Physics in Loop • Light Dark Matter (M~1GeV) No sensitivity to M<10 GeV in direct searches

  26. 535M BB B0 K*0nn : Belle (preliminary) _ [hep-ex/0608047] Exp. technique similar to B t+n Full-rec. tag & K + nothing 460K tags (1.7σ stat. significance) Sideband = 19 MC expectation = 18.73.3 SM Super B Factory LOI: 5σ observation of BK  will be possible with 50 ab-1

  27. Comments on Super B Factories

  28. Recent Developments for the Super B Factory Accelerator SuperKEKB design luminosity is now 8 x 1035/cm2/sec Low emittance/ILC inspired INFN/SLAC design is ~10 x 1035/cm2/sec c.f. Current KEKB luminosity is 1.7 x 1034/cm2 /sec To address the full array of new physics searches, require ~50 ab-1 of integrated luminosity c.f. Current KEKB integrated lumi 0.6 ab-1

  29. Ante-chamber & solenoid coils to reduce photo-electron clouds Super B Factory at KEK Interaction Region Crab crossing q=30mrad. by*=3mm New QCS New Beam pipe More RF power Damping ring Linac upgrade L = 81035/cm2 /sec

  30. Conceptual Design Report will be submitted to INFN soon. Question: 12 nanometer beam spot in y, 2.7 microns in x. Is this possible in a real 2-3 km circumference multi-orbit machine ?

  31. First step towards Super B: Crab crossing . Superconducting crab cavities (1 LER and 1 HER) have been installed and now are being tested at KEKB.

  32. Backup Slides

  33. The Super B Factory is part of a Unified and Unbiased Attack on New Physics n expts accel, reactor, gm-2, mgeg, etc. LHC, ILC Higgs boson mass and couplings. New particle searches n mass and mixing, CPV, and LFV Lepton sector Propagators New physics Quark sector • LFV, t CPV Flavor mixing, CPV phases Super B Factory, LHCb, Rare K expts, BESIII…

  34. Fundamental Questions in Flavor Physics Why three generations ? String Theory ? (e.g. P.Binetruy et.al., hep-th/0509157; J.Phys G.32: 129 (2006)); Larger Symmetry Groups ? Experiments with quarks or heavy leptons? This question is probably too hard – more tractable questions….. Are there New Physics Phases and New sources of CP Violation Beyond the SM ? Experiments: bs CPV, compare CPV angles from tree and loops Are there new operators with quarks enhanced by New Physics ? Experiments: AFB(BK*l l), BK  rates and asymmetries Are there right-handed currents ? Experiments: bs  CPV, B->VPγ or BV V triple-product asymmetries Are there new flavor changing neutral currents ? Experiments: bs ννbar, D-Dbar CPV+mixing+rare, τγ These questions can only be answered at a Super B Factory.

  35. Lessons of History New Physics is usually discovered first in loop processes, which involve high massvirtual particles. (Heisenberg Uncertainty Principle) Example I: Absence of KL allowed theorists to deduce the existence of the charm quark. The rate of K mixing allowed a rough determination of the charm mass. Example II: The absence of bs decays and the long B lifetime ruled out topless models. Large Bd mixing showed the top was heavy contrary to theory prejudices of the time. Radiative corrections from Z measurements determined the rough range of the top mass. Vtd Vtd Beautiful and precise measurements of the top quark mass at the Tevatron. However, the couplings |Vts|,|Vtd,|and most importantly the phase of (Vtd) cannot be measured in direct top production.

  36. http://www.jahep.org/hec/doc/jahep_tenbou_eng_final.pdf (An excerpt) ....

  37. K. Oide (Leading Japanese Accelerator Physicist) “Dai-repoton keikaku” Budget of Japanese acceleratorphysicists Official Announcement from KEK director A. Suzuki on Super B expected in 2007

  38. The Hunt for the EW Penguin:BXs l+ l- Discovered by CLEO in 1994 As in bs γ, heavy particles in the loops can be replaced with NP particles (e.g.W+  H+) Note contributions from virtual γ* , W, Z* and internal t quark.

  39. hep-ex/0508004, 88.9 MBB Eγ>1.9 GeV B → Xsγ from a sum of 38 exclusive decay modes

  40. b  sg : Belle result Efficiency corrected spectrum 140fb-1 Eg >1.8 GeV (cover 95.2%) B(B s g) = (3.55 0.32 ) x10-4 +0.30 +0.11 -0.31 -0.07 (Stat) (sys) (theo) Moments: <Eg> = 2.292 0.0260.034 GeV <Eg2> - <Eg>2 = 0.0311 0.0730.063 GeV2 useful for Vcb,Vub [hep-ex/0403004, PRL xxx] An update with much more data (x 3) is in progress

  41. SuperKEKB Projection for B g Ksp0g and other b g sg modes Possible deviation O(1): Warped extra dim. O(1): L-R symmetric model O(0.1): SUSY SU(5)

  42. B gfK0, h’K0, KsKsKs projection for SuperKEKB total errors (incl. systematic errors)

  43. Obtain CP parameters for 2-body and 3-body modes simultaneously by time-dependent Dalitz fit _ 347M BB New ! “Golden” mode:fK0 B0gK+K-K0 Dalitz tCPV K+K-KSgp+p- K+K-KSgp0p0 K+K-KL 151665 K+K-K0signal [hep-ex/0607112] MK+K-

  44. b  sg : Bkg subtraction backup B background B p0/h X: measured by data include in MC Continuum use OFF-resonance data (ECM 60 MeV lower)

  45. B  K(*)nn : Motivation _ b s with 2 neutrinos SM: B(BK* ) ~1.3 x 10-5 B (BK ) ~4 x 10-6 (Buchalla, Hiller, Isidori) _ _ PRD 63, 014015 • New Physics in Loop • Light Dark Matter (M~1GeV) No sensitivity in direct searches

  46. LHCb J. Libby 10 fb-1 for LHCb 50 fb-1 for SuperB The Super B Factory will face tough competition from LHCb, which is now a real experiment. There is considerable complementarity: photon, neutral detection and inclusive channels are considerable easier at the Super B Factory while time-dependent Bs studies are superior at LHCb.

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