New Physics in Rare Decays at Belle Toru Iijima Nagoya University March 4, 2006 KEK Theory Meeting 2006 “Particle Physics Phenomenology”

2 Conclusion No New Physics Indication Yet in Rare Decays ! (except for some puzzles) How significant is this fact ? Many peoples expect NP at TeV.

3 Search for New Physics in 3 rd Gen. Quark (B) and Lepton (  ) Decays Hadronic Penguin decays some puzzles ? Radiative decays Electroweak decays Tauonic decays Tau decays Lepton flavor violation Talk Outline Figure by Dr.Hayasaka (Nagoya Univ.) At present and future (Super-B)

4 Pattern of B Decays B meson is the heaviest meson in the 3 rd generation and its decay has several patterns. –Large b quark mass –Huge top mass –Small Vcb –Non-zero Vub B meson is an unique lab. To explore flavor mixing and CP violation.  1,  ,  3 -V cb, V ub, V td Many loops - box and penguin W exchange coupled to  

5 Belle Detector 7 sub-detectors for precise –Vertexing, –Tracking, –Particle ID, –Calorimetry

6 Belle Collaboration 13 countries, 57 institutes, ~400 collaborators IHEP, Vienna ITEP Kanagawa U. KEK Korea U. Krakow Inst. of Nucl. Phys. Kyoto U. Kyungpook Nat’l U. EPF Lausanne Jozef Stefan Inst. / U. of Ljubljana / U. of Maribor U. of Melbourne Aomori U. BINP Chiba U. Chonnam Nat’l U. U. of Cincinnati Ewha Womans U. Frankfurt U. Gyeongsang Nat’l U. U. of Hawaii Hiroshima Tech. IHEP, Beijing IHEP, Moscow Nagoya U. Nara Women’s U. National Central U. Nat’l Kaoshiung Normal U. National Taiwan U. National United U. Nihon Dental College Niigata U. Osaka U. Osaka City U. Panjab U. Peking U. U. of Pittsburgh Princeton U. Riken Saga U. USTC Seoul National U. Shinshu U. Sungkyunkwan U. U. of Sydney Tata Institute Toho U. Tohoku U. Tohuku Gakuin U. U. of Tokyo Tokyo Inst. of Tech. Tokyo Metropolitan U. Tokyo U. of Agri. and Tech. Toyama Nat’l College U. of Tsukuba Utkal U. VPI Yonsei U.

7 e + source Ares RF cavity Belle detector SCC RF(HER) ARES(LER) The KEKB Collider e - (8.0GeV) × e + (3.5GeV) ⇒  (4S) → BB ⇒ Lorentz boost:  = Finite crossing angle - 11mrad ×2 Operation since Peak luminosity 1.63 x cm -2 s -1 ! Integrated luminosity >560fb -1

8 KEKB Performance Records as of Mar.1,’06 L peak = 1.63x10 34 cm -2 s -1 L day = pb -1 /day L int = (Mar 1,’06) CESR KEKB L int /month Record = 27.9fb -1

9 KEKB Upgrade Scenario ~10 10 BB/year !! & similar number of  +  - L peak = 1.4  cm -2 s -1 L tot = 330fb -1 (Nov.30, 2004) 1.4x fb -1 5x10 34 ~1 ab -1 5x10 35 ~10 ab -1 L peak (cm -2 s - 1 ) L int Crab cavities Major upgrade of KEKB & Belle detector (>1yr shutdown) world records !

10 Rare Decay Milestone Observation of B  K l + l - Large CP Violation in B Observation of Large CPV and evidence of direct CPV in B   +  - Beginning of B->  K 0 saga Direct CPV in B 0  K +   Observation of b  d  FB asymmetry in B  K* l + l - Successful operation of B factories has enabled us to –Measure the B decays in different patterns. –Measure not only branching fraction, but also more details CP asymmetry B + /B 0 difference Distribution (Mx in b  s , A FB in B  K*ll) Successful operation of B factories has enabled us to –Measure the B decays in different patterns. –Measure not only branching fraction, but also more details CP asymmetry B + /B 0 difference Distribution (Mx in b  s , A FB in B  K*ll)

11 Direct CPV in B  K  Remarkable progress in the B-factory era. CLEO w/ 2.6M BB: [PRD53,1039(1996)] PID for high momentum K/ . 386 x 10 6 BB hep-ex/

12 K  puzzle ? Ratio of branching fraction Different sign of A cp (K +  - ) and A cp (K +  0 ). Possible reasons; Large EW-penguin (with large phase) Large color suppressed diagram ? Or both NP (ex. Z’) ?? No conclusion yet.

13 Possible to search for NP in theoretically clean way. Many observables; –Branching fractions –Mixing induced CPV –Direct CPV –Forward-backward asym. –Ratio of exclusive modes b  s  /sl + l - M(H + ) > 350 GeV already in TYPE II 2HDM Effective Hamiltonian for b  s |C 7 | by B  Xs , Sign of C 7, C 9, C 10 by B  Xsll

14 bsbs B  K* , PRD69, (2004) –85.0MBB b  s  (inclusive) PRD93, (2004) –152MBB 140fb -1 E  > 1.8 GeV CKM2005)

15 bdbd 386M BB qq background suppression; –Event shape –Decay vertex –Flavor tagging quality Hep-ex/ v2 BELLE preprint Submitted to PRL w/ constraint from isospin relation w/ Br(B  K*  )

16 Measurement of B(B  X s l + l - ) Semi-inclusive technique –X s is reconstructed from K + or K s  (at most one  0 is allowed) –M Xs < 2.0 GeV Electron or muon pair –M ll >0.2GeV –Charmonium veto 140/fb data Theoretical prediction by Ali et al. Wrong flavor M Xs q2q2 M. Iwasaki et al. submitted to PRD, hep-ex/

17 C 7 = -C 7 SM Constraints on C i from B(B  X s l + l - ) Clean prediction for B(B  X s ll) with 1<q 2 <6GeV 2 is available. –Combine Belle and Babar results –Sign of C 7 flipped case with SM C 9 and C 10 value is unlikely. P.Gambino, U.Haisch and M.Misiak PRL (2005) BFBelleBabarWASMC 7 = -C 7 SM q 2 >(2m  ) ±1.15.6±2.04.5±1.04.4±0.78.8±0.7 1<q 2 <6GeV 2 1.5±0.61.8± ± ± ±0.25 C 10 NP C 9 NP Donut : 90% CL allowed region C 7 SM SM

18 B  K * ll FB Asymmetry Good electroweak probe for b  s loop. q 2 distribution has different pattern depending on sign(C 7 ). q 0 (the point w/ A FB =0) is sensitive for New Physics SM; q 0 2 =(4.2±0.6)GeV 2 B K*K* ll ll  B K*K* ll ll  Forward Backward T. Rizzo M=1.5TeV M=1 TeV A FB w/ KK gravition exchange

19 A 9 /A 7 A 10 /A 7 A FB : Belle Summer ‘05 357fb -1 (386M BB) N(K*ll)= (purity 44%) Unbinned M.L. fit to d  2 /dsd(cos  ) –8 event categories Signal + 3 cross-feed + 4 bkg. –Ali et al’s form factor –Fix |A 7 | to SM –Float A 9 /A 7 and A 10 /A 7 Results; w/ negative A 7 (SM like) w/positive A 7 ＳＭ A9/A7 A10/A7 Sign of A 9 A 10 is negative ! See Hep-ex/ & A.Ishikawa’s talk at EPS05

20 Prospect at 5ab -1  C 9 ~ 11%  C 10 ~14%  q 0 2 /q 0 2 ~11% 1000 pseudo experiments w/ SM input values Expected precision 5% at 50ab -1

21 B  l  ; leptonic decays Proceed via W annihilation in the SM. Branching fraction is given by Provide information of f B |V ub | –|V ub | from B  X u l f B cf) Lattice (  ~16%) –Br(B  l )/  m d |V ub | / |V td | Expected branching fraction

22 Status of Leptonic Decay Search Summer’05

23 Full Reconstruction Method Fully reconstruct one of the B’s to tag –B production –B flavor/charge –B momentum Υ(4S) e  (8GeV) e+(3.5GeV) B B  full (0.1~0.3%) reconstruction B  D  etc. Single B meson beam in offline ! Decays of interests B  Xu l, B  K  B  D ,  Powerful tools for B decays w/ neutrinos

24 Fully Reconstructed Sample Belle (253fb -1 ): 275M BB  2.5x10 5 B 0 B x10 5 B + B -

25 B   Status (Belle LP05/EPS05) N BB (produced) = 275M N B + B - (full recon.) = 4.0 x 10 5 (purity 0.55) Searched  decay modes –Cover 81% of the  decay Event selection –Residual ECL energy –Total net charge etc. Obtained E residual K.Ikado’s talk at EPS05 hep-ex/

26 Prospect Will soon reach the SM. –3  at ~700 fb -1 –5  at ~2 ab -1 Expected precision at Super-B –13% at 5 ab -1 –7% at 50 ab -1 B   will be the next major milestone of the Belle mission for rare decay search ! B   will be the next major milestone of the Belle mission for rare decay search !

27 Impact to Charged Higgs Br. with exchange 90%CL excluded region at present 95% CL excluded region at 5ab -1 (if B obs = B SM ) rHrH tan  /m H H/WH/W 

28 Charged Higgs in B  D  Charged Higgs modifies semileptonic decay rates. c b  WW   (the heaviest lepton) is the most sensitive. c b  HH  + exchange exchange (SM) Tanaka/ Miura

29 B  D  (MC studies) Use fully reconstructed samples. T decay modes Analysis cuts; –Reject events w/ p, KL –Reject D (*)  contamination –No remaining charged or  0 tracks –ECL residual energy –Angle between two ’s –Missing mass Signal BG

30 Cont’d 5ab -1 50ab -1 ModeNsigNbkg  dB/BNsigNbkg  dB/B % % Expectation at 5 / 50 ab -1 for B + decay 5  observation possible at 1ab -1 Signal selection efficiency 10.2% 2.6% 26.1% 13.3% Major background source Missing charged and  tracks from B  D (*) l X (incl. slow  )

31 Cont’d  (Form-factor) ~15%  (Form-factor) ~5% Constraint From b  s  Present limit From B  

32 Lepton Flavor Violation Quarks have flavor mixing. Neutrino mixing has been found. What about charged leptons ? ? ? (Original figure by Dr. Kuno / Osaka Univ.) B factory is also a tau factory

33   l  SUSY + Seasaw Large LFV   l  3l  l  Br(    )=O(10 -7~9 )   3l,l  Neutral Higgs mediated decay. Important when M SUSY >> EW scale.

34 Analysis Method Signal extraction –Calc. M inv and DE DE=E rec -E beam –Blinded signal region  Event selection study –Estimate background using sideband data –Open blind and estimate signal yield Estimate upper limits Signal MC of    Signal region Background

35    /e  at Belle    Background:    /e + ISR (or beam background) Small amount of mm events in  E>0 Br<3.1x10 -7 at 90%C.L. PRL 92, (2004). Br<3.1x10 -7 at 90%C.L. PRL 92, (2004). 86.3fb -1 data ee Br<3.9x10 -7 at 90%C.L. PLB 613, 20 (2005). Br<3.9x10 -7 at 90%C.L. PLB 613, 20 (2005).

36 ll Belle: 87.1fb -1, PLB 598, 103 (2004) Br<(1.1~3.5)x10 -7 at 90%C.L. Background: low level –qq for  E 0 Signal region

37 B.R. Summary Br < O(10 -6 ) in PDG (by CLEO)  Br < O(10 -7 ) by Belle and BaBar

38 Super B-factory : >10 times more data –B.R. sensitivity: ~1/n for negligible BG case ~1/  n for BG dominating modes Future prospect

39 Future prospect (2) Possible sensitivity with Super B-factory –Red band for 5~10ab -1 Super B-factory

40   l  SUSY + Seasaw Large LFV Constraint to NP Br(    )=O(10 -7~9 ) Gaugino mass = 200GeV Super-B Present Belle   3l,l  Neutral Higgs mediated decay. Important when M SUSY >> EW scale.

41 Interplay between B and  Tau04 Workshop, Nara, Nov, J.Hisano, Y.Shimizu PLB565(2003)183.

42 Concluding Remarks No New Physics Indication Yet ! Need more luminosity. This year: Crab cavity installation Future: Super-KEKB Stay tuned !

43 Future Let’s discuss together –Role of flavor physics –Synergy with LHC YESNO YES13 NO24 LHC Flavor Phys (ex. Super-B) NP evidence 1. We will be busy! Scenario of studies ? 2. Scenario of studies ? 3. How significant is the null result at F.P. to constrain NP model. 4. Where do we go ? 1. We will be busy! Scenario of studies ? 2. Scenario of studies ? 3. How significant is the null result at F.P. to constrain NP model. 4. Where do we go ?

44 CERN Flavor WS Nov. 7-10, 2005 Feb. 6-8, 2006 May.15-17, 2006 Final report at 2006/end or 2007/beg. Discuss synergy between Flavor Physics (B/C/K/t/m etc.) and LHC. Bench mark model & parameters for studies. Let’s discuss together !

45 Backup

46 Radiative Decays Inclusive Br(b  s  ) |C 7 |, SF for |V ub | B  K*  isospin asymmetry (  +-)sign of C 7 Mixing induced CPV Direct CPV in B  X s  B  X d  Summary by M.Nakao 1st Super-B workshop at Hawaii

47 B 0  K S  0  tCPV: Belle Summer ‘05 386MBB M(Ks  0 ) < 1.8GeV/c 2 –NP effect is independent of the resonance structure. Two M(Ks  0 ) regions(MR1: GeV/c 2 / MR2: <1.8GeV/c 2 ) (45+-11) events in MR1(2). Atwood, Gershon, Hazumi, Soni, PRD71, (2005) Result S= ±0.41 ±0.10 A= +0.12±0.27±0.10 Good tag (0.5<r<1.0) / 0.038A cp dir (B  Xs  ) / 0.10A cp mix (B  K*  K*  Ks  0 ) 50ab -1 5ab -1 Present Belle (stat./syst.)

48 A cp (B  X s  ) vs SUSY models mSUGURA tan  =30 U(2) tan  =30 SU(5)+ R tan  =30 degenerate SU(5)+ R tan  =30 non-degenerate mSUGURA tan  =30 U(2) tan  =30 SU(5)+ R tan  =30 degenerate SU(5)+ R tan  =30 non-degenerate Mixing CPV Direct CPV A cp dir A cp mix 5ab -1 50ab -1 T. Goto, Y.Okada, Y.Shimizu,T.Shindou, M.Tanaka hep-ph/ , also in SuperKEKB LoI

49 Constraint to Charged Higgs Once branching fraction is measured, we can constrain R. Form factor error M.Tanaka, Z.Phys. C67 (1995) 321 at 5ab -1  can be determined experimentally by B semiletonic decays