New Physics and Rare B Decays Tom Browder

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 Ba. Bar are covered; a few of the results are ~ 1 year old.

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)

How to find New Physics Phases Example: Vts: no KM phase * Vtd , h’, K+K- + Vtd* SM: f f , h’, K+K- B B eff sin 2 1 = sin 2 1 from f 1 _ B J/y K 0 (b c c s) unless there are other, non-SM particles in the loop

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

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) RS 1 ++CPV in D decay SM Model: K. K. Gluon near 3 Te. V

Belle 2006: t. CPV in _ 0 B gf 0 K 535 M BB “sin 2 f 1” = +0. 50 0. 21(stat) 0. 06(syst) a. k. a sin(2β) Dt distributions and asymmetry Consistent with the SM (~1 s lower) Consistent with Belle 2005 (Belle 2005: “sin 2 f 1” = +0. 44 0. 27 0. 05) unbinned fit SM Ø f. KS and f. KL combined Ø background subtracted Ø good tags Ø Dt g –Dt for f. KL hep-ex/0608039, PRL 98, 031802(2007)

Ba. Bar: f. K 0 using B 0 g K+K-K 0 _ 347 M BB [hep-ex/0607112] b measurement (not sin 2 b) f. K 0: sin 2 beff = +0. 12 ± 0. 31(stat) ± 0. 10 (syst) a. k. a. sin(2 φ1)

1 st Observation of t. CPV in a b s mode h’K 0 h’Ks h’KL unbinned fit SM 535 M BB 5. 6 s “sin 2 f 1” = +0. 64 0. 10 0. 04 _ 347 M BB >5 s “sin 2 f 1” = +0. 58 0. 10 0. 03 [hep-ex/0608039] PRL 98, 031802(2007) [hep-ex/0607100], PRL+Sept 28 press conf

2006: Hints of NP in b g s Penguins ? Smaller than bgccs in all of 9 modes Theory predicts positive shifts Naïve average of all b g s modes sin 2 beff = 0. 52 ± 0. 05 2. 6 s deviation from SM

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

Measurement of inclusive b sg Measure primary only: monochromatic E spectrum Huge Background (semi-log) experimental challenge Background suppression • continuum: event shape • 0/h veto Important to measure low E to reduce model dependence

Nakao

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

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)

Right-handed currents in b g s mb D. Atwood, M. Gronau, A. Soni, PRL 79, 185 (1997) D. Atwood, T. Gershon, M. H, A. Soni, PRD 71, 076003 (2005) ms • t. CPV in B 0 g (Ks 0)K* – SM: is polarized, the final state almost flavor-specific. S(Ks 0 g) ~ -2 ms/mbsin 2 f 1 ms mb – 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. 4 Te. V) |S(Ks 0 g)| ~ 0. 5 is allowed. – No need for a new CPV phase Photon polarization measurement via time dependent CPV !

Status of B KS 0γ t. CPV 535 M BB Yield = 176+/- 18 M(Ks p 0) < 1. 8 Ge. V _ 232 M BB (-C) hep-ex/0608017, PRD-RC 74, 111014(2006) No new physics but errors on S are large

Rare Decays with Large “Missing Energy”

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

Why measuring B ν is non-trivial e+ BB- X (4 S) B+ e Most of the sensitivity is from tau modes with 1 prong B+ + , + e+ e The experimental signature is rather difficult: B decays to a single charged track + nothing

Example of a B ν candidate Tag: B D 0 , D 0 K Very difficult or impossible at a hadron collider

Evidence for B+ ν (Belle) 449 106 B pairs Btag D(*)[ , r, a 1, Ds(*)] 680 k tags, 55% pure. 5 decay modes Find signal events from a fit to a sample of 54 events. 4. 6 s 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

B+ ν (Ba. Bar preliminary) Awaiting Ba. Bar’s analysis with hadronic tags

Direct experimental determination of f. B • Product of B meson decay constant f. B and CKM matrix element |Vub| • Using |Vub| = (4. 39 0. 33)× 10 -3 from HFAG ( Belle) (PRL 97, 251802 (2006)) Theory: f. B = 216 22 Me. V (an unquenched lattice calc. ) [HPQCD, Phys. Rev. Lett. 95, 212001 (2005) ]

Constraints on charged Higgs mass Use known f. B and |Vub | exc lud ed Ratio to the SM BF. 44 9 M excluded Compare to direct searches for H+ r. H=1. 13 0. 51

nn : Motivation _ B (*) K 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~1 Ge. V) DAMA Na. I 3 s Region S DM C No sensitivity to M<10 Ge. V in direct searches 04 05

0 K* nn : Belle (preliminary) _ 0 B Exp. technique similar to B + [hep-ex/0608047] Full-rec. tag & K + nothing 535 M BB 460 K 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

Comments on Super B Factories

Recent Developments for the Super B Factory Accelerator Super. KEKB design luminosity is now 8 x 1035/cm 2/sec Low emittance/ILC inspired INFN/SLAC design is ~10 x 1035/cm 2/sec c. f. Current KEKB luminosity is 1. 7 x 1034/cm 2 /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

Super B Factory at KEK Interaction Region Crab crossing q=30 mrad. by*=3 mm New QCS New Beam pipe More RF power Ante-chamber & solenoid coils to reduce photo-electron clouds Damping ring Linac upgrade L = 8 1035/cm 2 /sec

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 ?

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.

Backup Slides

The Super B Factory is part of a Unified and Unbiased Attack on New Physics expts accel, reactor, g -2, ge , etc. LHC, ILC op tor Pr mass and mixing, CPV, and LFV ec New physics ns ag a to pto rs Le Higgs boson mass and couplings. New particle searches Quark sector LFV, CPV Flavor mixing, CPV phases Super B Factory, LHCb, Rare K expts, BESIII…

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

Lessons of History New Physics is usually discovered first in loop processes, which involve high mass virtual 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 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.

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

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

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.

B → Xsγ from a sum of 38 exclusive decay modes hep-ex/0508004, 88. 9 MBB Eγ>1. 9 Ge. V

b sg : Belle result Efficiency corrected spectrum E >1. 8 Ge. V (cover 95. 2%) 140 fb-1 B(B s ) = +0. 11 -4 (3. 55 0. 32 +0. 30 ) x 10 -0. 31 -0. 07 (Stat) (sys) (theo) Moments: <E > = 2. 292 0. 026 0. 034 Ge. V <E 2> - <E >2 = 0. 0311 0. 073 0. 063 Ge. V 2 useful for Vcb, Vub An update with much more data (x 3) is in progress [hep-ex/0403004, PRL xxx]

Super. KEKB Projection for B g Ks 0 and other b g s modes Possible deviation O(1): Warped extra dim. O(1): L-R symmetric model O(0. 1): SUSY SU(5)

B g f. K 0, h’K 0, Ks. Ks projection for Super. KEKB total errors (incl. systematic errors)

“Golden” mode: f B 0 g K+K-K 0 Dalitz t. CPV 0 K • Obtain CP parameters for 2 -body and 3 -body modes simultaneously by time-dependent Dalitz fit K+K-KSg + K+K-KSg 0 0 K +K -K L _ 347 M BB 1516 65 K+K-K 0 signal [hep-ex/0607112] MK+K-

backup b sg : Bkg subtraction Continuum use OFF-resonance data (ECM 60 Me. V lower) B background B 0/h X: measured by data include in MC

nn : Motivation _ B (*) K 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~1 Ge. V) No sensitivity in direct searches

LHCb J. Libby 10 fb-1 for LHCb The Super B Factory will face tough competition 50 fb-1 for Super. B 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.