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B ファクトリーの成果と Super-B. Jan.19, 2005 @京都大学 山内正則 KEK. 2 Im ( l f ). | l f | 2 + 1. CP violation in B B system. 0. 0. Standard model predictions. | l f | 2 - 1. A f =. | l f | 2 + 1. -x f. S f =. A( B g f ). l f ≡ e -2 i f M. A( B g f ).
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Bファクトリーの成果とSuper-B Jan.19, 2005 @京都大学 山内正則 KEK
2Im( lf) | lf|2 + 1 CP violation in B B system 0 0 Standard model predictions | lf|2 - 1 Af= | lf|2 + 1 -xf Sf = A( Bgf ) lf≡e-2ifM A( Bgf ) Note: Af = 0 aG(Bgf ) = G(Bgf ) a direct CP violation.
CKM quark mixing matrix The fi’s and CKM matrix Unitarity Unitarity triangle * -VtbVtd -VcbVcd f1≡p-arg( ) * VtbVtd -VubVud * f2≡arg( ) *
Principle of the measurement G(BgfCP;t ) can be measured. Large data sample Af and Sf
Old result of sin2f1 (Belle, Feb. 2002, hep-ex/0205020) 441.8 fb-1 4 6 bgccs decay modes (BgJ/yKS, J/yKL etc.) 4Sccs = sin2f1 = 0.82±0.12±0.05 4|lccs| = 1.01 (stat.) i.e., Accs is consistent with 0. 1550 events +0.08 -0.07
Mt. Tsukuba KEKB Belle ~1 km in diameter KEKB Collider 8 GeV e- x 3.5 GeV e+ 11mrad crossing Lpeak = 1.39 x 1034 sec-1cm-2 @ 1.2A x 1.6A - 275M BB 253 fb-1 on Y(4S) 28 fb-1 below Y(4S) ~287 fb-1
Continuous Injection No need to stop run Always at ~max. currents, luminosity [CERN courier Jan/Feb 2004] both KEKB & PEP-II ~30% more L dt continuous injection (new) normal injection (old) HER current LER current Luminosity ~1 fb-1/day ! (~1x106 BB) - 0 12 24 Time
Belle Collaboration U. of Maribor U. of Melbourne Nagoya U. Nara Women’s U. National Central U. Nat’l Kaoshiung Normal U. Nat’l Lien-Ho Inst. of Tech. Nat’l Taiwan U. Nihon Dental College Niigata U. Osaka U. Osaka City U. Panjab U. Peking U. Princeton U. Riken Saga U. USTC Seoul National 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 A and T. Toyama Nat’l College U. of Tsukuba Utkal U. IHEP, Vienna VPI Yokkaichi U. Yonsei U. Aomori U. BINP Chiba U. Chuo U. U. of Cincinnati Frankfurt U. Gyeongsang Nat’l U. Hiroshima Tech. IHEP, Beijing ITEP Kanagawa U. KEK Korea U. Krakow Inst. of Nucl. Phys. Kyoto U. Kyungpook National U. U. of Lausanne Jozef Stefan Inst. w w w w w w w w w w w w w w w w w w w w w w w w w
Belle Detector Aerogel Cherenkov cnt. n=1.015~1.030 SC solenoid 1.5T 3.5GeV e+ CsI(Tl) 16X0 TOF counter 8GeV e- Tracking + dE/dx small cell + He/C2H5 m / KL detection 14/15 lyr. RPC+Fe Si vtx. det. 3 lyr. DSSD
cc1,cc2J/y+g s=7.0 MeV/c2 y’ sM=4.1 MeV/c2 cc1 cc2 y’m+m-,e+e- s=12.1 MeV/c2 sM=9.3 MeV/c2 in inclusive J/y events Mll (GeV/c2) M(KSp0p0) (GeV/c2) Mllg-Mll (GeV/c2) M(KSp+p-) (GeV/c2) Sub decay modes J/y m+m- s=9.6MeV/c2 J/y e+e-(g) s=10.7MeV/c2 Mll (GeV/c2) p0
bkg sin2f1: charmonium K0 Belle 2003 BABAR Update for ICHEP04 Belle CONF-0436 BABAR PUB-04/038
Current Results for sin2f1 sin2f1(2004 World Av.) = 0.726±0.037 [LP2003: 0.736 ±0.049] precisionmeasurement (~5%) Good SM reference
152M BB App Spp B0p+p CPV Result Direct CPV 3.2s good tag Dt (ps) App = +0.58 0.15(stat) 0.07(syst) Spp = 1.00 0.21(stat) 0.07(syst) [PRL93,021801 (2004)]
History of App and Spp B0p+p TCPV Belle Difference at ~3.1s level (was ~2.2s) BaBar 227MBB New
W _ _ s/d Vtb t K/p+ W u s/d g K/p+ u u Vub 0 d B _ _ G(Bf ) - G(Bf ) p- p- d d u d d _ _ G(Bf ) + G(Bf ) ACP = 0 d B b b Vts/d Vus/d Direct CPV: B Kp Tree Penguin • Simplest charmless rare decay modes • Tree - Penguin interference Direct CP Violation Key prediction of Kobayashi-Maskawa model Observation in B Strong support of KM
274M BB New ACP(B0 K+p-) _ B0 K-p+ B0 K+p- Signal: 2139 53 [submitted to PRL] ACP = -0.101 0.025 0.005 3.9ssignificance [PID efficiency bias correction: dA = -0.01 0.004] 2ndEvidence for DCPV at Belle ! [A(p+p-) 3.2s]
227M BB ACP(B0 K+p-) hep-ex/0408057, submitted to PRL BABAR 4.2s Average of Belle and BaBar > 5s First established Direct CPV in B decays !
274M BB New ACP(B K+p0 ) Kp0 : 728 53 ACP(Kp0) = 0.04 0.05 0.02 0.06 0.06 0.06 (BaBar, 227M) Average d p0 _ d hint thatACP(K+p- ) ¹ACP(Kp0 ) ? (3.6s) Large EW penguin (Z0) ? New Physics ? B- b s K- u u
- b b d d d d s s X t s s s s New physics Search : b sqq f f _ B0 + KS KS B0fKs 68 ev “sin2f1”= -0.96 0.51 3.5s deviation from the SM ! Belle @LP03
274M BB pB* B0f K0 fKS Nsig=139 14 fKL purity 0.63 Nsig= 36 15 purity 0.17 Similar to J/yKL recon. + sophisticated continuum suppression includes Ks p0po (Nsig=13 5)
274M BB S = 0.736 fit B0f K0 : CPV Result f K0 Good tags Poor tags Good tags fKS+fKL:S(fK0) = +0.06 0.330.09 A(fK0) = +0.080.220.09 ~2.2s away from SM
274M BB S = 0.736 fit B0h’KS high statistics modes h’KS BABAR h’rg, hp+p- (hgg, p+p-p0) Nsig=512 27 purity 0.61 Raw Asymmetry Good tags (~0.5s @SM) S = +0.65 0.18 0.04 A = -0.19 0.11 0.05
3.6s from s-penguin to sin2b (cc) Averages for sin2b and s-penguin modes No sign of Direct CP in averages
aEW Radiative & EW Penguins Loops Sensitive to New Physics l+ l- b sl+l- penguin ~1/100 b sg penguin Br, ACP ~SM b dg penguin K*g TCPV
274M BB B K(*) l+l- LP03: B Xsll, K(*)ll : first observed by Belle, confirmed by BaBar Br, ACP ~SM update >10s signals 82 11 signals 79 10 signals B (Kll)= (5.50 0.27 0.02) 0.75 0.70 B (K*ll)= (16.5 0.9 0.4) 2.3 2.2 x 10-7 [Belle-conf-0415]
274M BB K* B K* l+l- :FB Asymmetry AFB(K*ll ) : very sensitive to NP that may not be seen in B(bsg) raw AFB q2 First Look ! q2 [Belle-conf-0415]
Road Map of B Physics Identification of SUSY breaking mechanism Anomalous CPV in bgsss sin2f1, CPV in Bgpp, f3, Vub, Vcb, bgsg, bgsll, new states etc. if NP=SUSY Study of NP effect in B and t decays time or integrated luminosity Precise test of SM and search for NP Yes!! NP discovered at LHC(2010?) Discovery of CPV in B decays Now 340 fb-1
New CPV phase FCNC decays Precision CKM LFV decays Higgs Search Global Analysis of B Physics (Study of New Physics Scenario) Physics Program at Super-B
Off-diagonal terms Flavor Physics Luminosity frontier Diagonal terms: LHC/ILC Energy frontier Physics at Super-B = SUSY Flavor Physics Its importance is independent of LHC results. (VCKM could not be pin down only with energy frontier) Investigating SUSY in flavor physics Mass+mixing angle+phase • MSSM parameters > 100 ! • The squark/slepton mass matrix • Sensitive to SUSY breaking mechanism. • New sources of flavor mixing Baryon asymmetry ?
Lpeak (cm-2s-1) Lint 1.4x1034 280 fb-1 5x1035 10 ab-1 5x1034 1 ab-1 Super-KEKB Super-KEKB (major upgrade) Projection of KEKB luminosity 5x109 BB /year !! & alsot+t- Taget Luminosity 5x1035 cm-2s-1 Crab cavity
Expectation at 5ab-1 J/y KS0 fK0 (input S=+0.24) Expected Precision Statistical significance w/ the present central value DS theory error fK0: ~0.05 h’K0: ~0.10
Pattern of the deviation from the SM prediction Y.Okada Unitarity triangle Rare decay ++: Large, +: sizable, -: small
280fb-1 5ab-1 50ab-1 Acp(BfKs) vs SUSY models U(2) tanb=30 mSUGURA tanb=30 Acpmix Acpが比較的小さければ早期にズレははっきりする。 その場合、M(gluino)~500GeVを示唆する。 SU(5)+nR tanb=30 degenerate SU(5)+nR tanb=30 non-degenerate
Acp(BXsg) vs SUSY models 50ab-1 5ab-1 Mixing CPV Direct CPV U(2) tanb=30 mSUGURA tanb=30 U(2) tanb=30 mSUGURA tanb=30 Acpdir Acpmix SU(5)+nR tanb=30 non-degenerate SU(5)+nR tanb=30 degenerate SU(5)+nR tanb=30 non-degenerate SU(5)+nR tanb=30 degenerate 5ab-1 ではM(gluino)=1TeV, 50ab-1では2TeVまで攻める。
FB asymmetry in bsl+l- • Sensitive probe for NP (theoretically clean) Br(BXsg), D0+(BK*g) 2 2 1 SM SM(0,0) 1 3 3 Bound from present Br(Xsl+l-) SUSY Scan (MFV)
FB asymmetry in bsl+l- (cont’d) • Present status (250fb-1) • At Super-B どこで Zero-cross するか? MC (5ab-1) MC (50ab-1) Identify rough pattern (sign flip bet. low q2/high q2) dC9~10%, dC10~14% まで制限可能 PID(m/p)も重要。 Branching fractionのdilepton mass分布の測定も有効。
B • Interesting decays • B → uln • B → tn, Knn • B → Dtn • etc Υ(4S) e- (8GeV) B e+(3.5GeV) p full tagging Full reconstruction • 片側のB中間子を完全再構成して反対側のB崩壊をtagする。 • 特に、n, t を含む崩壊の精密測定や探索に威力。e+e- B factory でのみ可能。 “オフラインB中間子ビーム” 運動量、電荷、フレーバー既知 • B Dtn: 12 s observation • at 5 ab-1. • BKnn: 5 s observation • at 50ab-1.
H+/W+ t+ Charged Higgs 探索 • Btn (leptonic decay) nt Present status
c b H+/W+ t+ nt Charged Higgs 探索 • BDtn (semileptonic decay) バンド幅:Form-factor による不定性 • Signal large missing mass • Expected at 5ab-1
現在のBtn による制限 Sensitivity for charged Higgs BDtn BXs gによる制限 D(Form-factor) ~5% D(Form-factor) ~15% 現状 LHC 100fb-1 D(form-factor)は 現在のBDmn データで測定可能 LHCとの先陣争い。
Lepton Flavor Violation LFV in neutrino sector already seen (at maximal mixing). ⇒LFV in charged leptons ? Tau lepton • The heaviest lepton • 3rd generation B-factory = “Tau-factory” • s(tt) ~ s(BB) • 5x109t pairs at 5ab-1 Enhancement in the rate ex.) Br(tmg)~104-5 x Br(meg) Both 32(m)/31(e) transition can be explored ⇒slepton flavor structure. Rare decay sensitivity at O(10-9)
Belle (tmg) tmg measurements • Present Belle results (86fb-1, 7.9x107 t-pairs) • Br(tmg) < 3.1 x 10-7 (90%CL) • Br(teg) < 3.8 x 10-7 (90%CL) Expected signal distribution Background mmg Mis-id (mp) ttg generic Escape from missing mass cut • Improvement • Analysis (selection criteria, cut analysis likelihood analysis) • Particle ID (better rejection of mp fake) • g energy resolution
w/ improvement Extrapolation First result Expected sensitivity for t→mg 600/fb at B-factory tlg Simple extrapolation from the present tlp/h/h’ t3l tl Ks w/ improvement tB g/p Search region enters into O(10-810-9) Tau LFV search (pastfuture)
Present Belle Super-B Gaugino mass = 200GeV tmg/eg • SUSY + Seasaw • Flavor violation by n-Yukawa coupling. • Large LFV Br(tmg)=O(10-7~9) Similar for eg case 探索可能な領域 (max. )
tmg in SUSY GUT Squark/slepton mass matrix relation SU(5) GUT+nR Correlation to Acpmix(BXsg) and Acpmix(BfKs) These correlations provides non-trivial test of SUSY GUT
CKM fit |Vub| |Vtd| • Determine (r,h) only by tree processes (SM dominant). • |Vub| from bguln • f3 from BgDK • Compare it with (r,h) determined through • |Vtd| from BB mixing, i.e. DMd • f1 from BJ/yKS • This gives M12=M12SM+M12NP f1 from BJ/yKS f3 from BgDK
Vub & f3 Vub & f3 sin2f1 & Dmd sin2f1 & Dmd UT at Super-B 5 ab-1 50 ab-1
5ab-1 50ab-1 UT vs SUSY models Dm(Bs)/Dm(Bd) SU(5)+nR tanb=30 degenerate mSUGRA tanb=30 SU(5)+nR tanb=30 non-degenerate U(2) tanb=30 f3 (degree)
“ずれ”>5sとなる領域 5ab-1 50ab-1 1ab-1 SM fKS K+K-KS h’KS S bsss K*g Summary-1 • New CPV phase の発見可能性 • 中心値による • 5ab-1で可能(2012年頃?) • Bsss 平均については1ab-1でも可(2007年)
1ab-1 10ab-1 5ab-1 Super- KEKB KEKB 50ab-1 へ fKs, h’Ks bsss New CPV phase claim SU(5), mSUGRA? Study of NP scenario Global B Analysis K*g 決着 LFV tlg,lh.lll ~5x10-8 ~1x10-8 ~5x10-9 発見の可能性大。 Charged Higgs BDtn 発見なら精密測定を目指す(検出器改良)。 発見の可能性はある(tanb大)。 LHCが100fb-1貯める前に逃げ切る。 MSUSY大 見つからない? MSUSY小 確認 Summary-2 2010 2005 2015 Discovery phase Investigation phase Acp<0 or 小 なら早期発見もありうる。 M(gluino)~500GeVを示唆 2TeVまで可能。 LHC