Current Status of Physics Future Prospect KEKB Toru
Current Status of Physics & Future Prospect @ KEKB Toru Iijima / Nagoya University NP SM Higgs Figure by Dr. Hayasaka (Nagoya Univ. ) June 20, 2007 Supersymmetry in 2010’s @ Hokkaido Univ.
Talk Outline n Introduction n Current status: CP violation & CKM Tree 1: What we already see. n Recent Topics: – Decay with missing energy B t n, D* t n Tree 2: What we starting to see. n Future Prospect B/t physics in the LHC era Super B-Factory Tree 3: What we will see. n Summary The Road to NP 2007/6/21 Toru ijima, SUSY 2010's 2
The KEKB Collider - (8. 0 Ge. V) × e+ (3. 5 Ge. V) n e Belle detector ⇒U(4 S) →BB SCC RF(HER) ⇒Lorentz boost: b = 0. 425 n Finite crossing angle - 11 mrad × 2 n Operation since 1999. ARES(LER) Ares RF cavity Peak luminosity e+ source 1. 71 x 1034 cm-2 s-1 !
Belle Detector 2007/6/21 Toru ijima, SUSY 2010's 4
International Collaboration: Belle 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 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 Nagoya U. Nara Women’s U. National Central U. National Taiwan U. National United U. Nihon Dental College Niigata 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 Inst. of Tech. Tokyo Metropolitan U. Tokyo U. of Agri. and Tech. Toyama Nat’l College U. of Tsukuba VPI Yonsei U. 13 countries, 55 institutes, ~400 collaborators
Integrated Luminosity As of Mar. 15, 2007 KEKB/Belle: 709. 9 fb-1 U(4 S): 620. 6 fb-1 U(5 S): 21. 2 fb-1 U(3 S): 2. 9 fb-1 Off-peak: 58. 9 fb-1 KEKB for Belle PEP-II for Ba. Bar PEP-II/Ba. Bar: 406. 2 fb-1 2007/6/21 Toru ijima, SUSY 2010's 6
Search for Light Dark Recent Hot Topics Matter. PRL 98, 132001 (200 Results of Y(3 S) running (2. 9 fb-1 w/ special trigger) Even if U(1 S) is invisible, we can observe via cascade decay Y(3 S) p+ p- Y(1 S)invisible as a recoil mass peak p+ -3 (90%C. L. Br(Y(1 S) invisible) < 2. 5 x 10 p- Disfavored U(1 S) No way to search Light dark matter for direct search experiments The heaviest quarkonium, Upsilon U, has potential for Invisible (i. e. Dark Matter) decay Phys. Rev. D 72, 103508 (2005) Demonstration with control sample data. Y(3 S) p+ p- Y(1 S), Y(1 S) m+m- Fit BG Prediction in Phys. Rev. D 72, 1035 (2005) Br(Y(1 S) invisble)=6. 0 x 10 -3
Belle Physics Milestone Exciting results every year ! # of publications = ~40 / year 219 in total (submitted) Evidence of D 0 mixing Observation of DCPV in B p+p. Evidence of B tn Observation of b d Direct CPV in B 0 K+p. Discovery of X(3872) Hint of NP in B->f. K 0 Observation of B K l+ l. Large CP Violation in B 2007/6/21 Toru ijima, SUSY 2010's 8
Tree 1: Current status: CP violation & CKM The Road to NP 2007/6/21 Toru ijima, SUSY 2010's 9
B Decays and the Unitarity Triangle B→pp B→ p “Time-dependent CP asym. (Indirect CPV)” B-B mixing Inclusive b→uln Exclusive pln, … B→ /B→K* B→DK B→f. K B→pp/Kp & Other charmless decays “Partial rate asym (Direct CPV)” 2007/6/21 Inclusive b→cln Exclusive D* ln, … Toru ijima, SUSY 2010's B→J/Y Ks 10
Hazumi@Flavour in era of LHC Mar. 2007 sin 2 f 1 = 0. 678 0. 025 (4% accuracy) World avg. (f 1 = 21. 3 1. 0 deg. ) (i. e. with OPAL, ALEPH, CDF) Average with B factories only PRL 98, 031802 (2007) B 0 g J/ K 0 hep-ex/0703021 B 0 g J/ K 0, (2 S)KS, hc. KS, c 1 KS, J/ K*0
CPV in b s Penguin Processes • Heavy particles may be mediated in the quantum loop. • In SM, CPV(B 0 f. Ks) = CPV(B 0 J/y. Ks) • If a new particle carries a quantum new phase CPV(B 0 f. Ks) ≠CPV(B 0 J/y. Ks) f. NP ? 2007/6/21 Toru ijima, SUSY 2010's 12
Hazumi@Flavour in era of LHC Mar. 2007: f 1 with b g s Penguins Smaller than bgccs in all of 9 modes Theory tends to predict positive shifts (originating from phase in Vts) Naïve average of all b g s modes sin 2 beff = 0. 53 ± 0. 05 2. 6 s deviation between penguin and tree (b g s) (b g c) More statistics crucial for mode-by-mode studies
Num. of Ev. f 2: B p+p 300 200 Asym. 100 hep-ex/0608035 535 MBB App = +0. 55 0. 08 0. 05 Spp = -0. 61 0. 10 0. 04 Direct CPV @ 5. 5 s 0 +1 0 -5 Num. of Ev. -1 0 5 Dt (ps) B 0 tag Asym. B 0 tag hep-ex/0703016 383 MBB Cpp (-App) = -0. 21 0. 09 0. 02 Spp = -0. 60 0. 11 0. 03 CPV @ 5. 5 s deg. 2007/6/21 Dt (ps) Toru ijima, SUSY 2010's 14
f 3: B DK(*) n Use DCPV via interference between b c and b u tree decays. V* b W + d B l 3 ub Vcs u l 3 u 0 c. D f. COM + d b B s + K u u Vus W s u K+ V*cb c _ D 0 f. COM u n Three methods are used – GLW (D 0 f. CP) – ADS (DCSD) – GGSZ (Dalitz) /f 3 = [62 +38 -24 ] 2007/6/21 Toru ijima, SUSY 2010's 15
|Vub| Measurement n Semileptonic decays are the most common utilities. |Vub| from inclusive b u n Measurement of b→uln(ICHEP 2006, suffer from. BLNP) O(103) larger b→cln background, and need introduce a cut extrapolation error. n In B factory era, tagging allows us to measure not only Pl, but also Mx and q 2, by which the extrapolation error can be reduced. Pl at endpoint Belle, PLB 621, 28(2005) L ~80% Mx (hadron mass) Belle, PRL 95, 141801(2005) ~10% 2007/6/21 Toru ijima, SUSY 2010's 16
|Vtd| n BB mixing (~4% accuracy) exp. theo. . n B /K* Vts B Belle+Ba. Bar 2007/6/21 s, d Toru ijima, SUSY 2010's 17
Success of B Factories KM model of CPV has been firmly established. n sin 2 f 1= +0. 678± 0. 025 is now a precise measurement (~4%). n The other angles are becoming interesting. – f 2 from rr /rp /pp – 2 f 1+f 3 from B D(*)p – f 3 from B DK (w/ D Dalitz) + side measurements too. |Vcb|, |Vub|. Dmd , Dms Paradigm change: look for Alternatives to CKM Corrections by NP Need far precise tests
Tree 2: Recent Hot Topics: tn / D(*) t n H+ The Road to NP 2007/6/21 Toru ijima, SUSY 2010's 19
B t n n Proceed via W annihilation in the SM. n SM Branching fraction is given by + W H+/W+ t+ t+ f. B determination n Sensitive to the charged Higgs 2007/6/21 Toru ijima, SUSY 2010's 20
Full Reconstruction Method n Fully reconstruct one of the B’s to tag – B production – B flavor/charge – B momentum B e- (8 Ge. V) e+(3. 5 Ge. V) Υ(4 S) p B Decays of interests B Xu l n, B K n n B Dtn, tn full (0. 1~0. 3%) reconstruction B Dp etc. Single B meson beam in offline ! Powerful tools for B decays w/ neutrinos
B tn Candidate Event B + g D 0 p + K+ p- p+ p. B- g t - n e-nn
The 1 st Evidence of B t n n The final results are deduced by unbinned likelihood fit to the obtained EECL distributions. Signal + background S : Statistical Significance Background B tn Signal Observe 17. 2 +5. 3 - 4. 7 events. Significance decreased to 3. 5 s after including systematics Signal shape : Gauss + exponential Background shape : second-order polynomial + Gauss (peaking component) PRL 97, 251802 (2006)
Constraints on Charged Higgs B r. H 2 s B 2007/6/21 A A Toru ijima, SUSY 2010's 24
B D(*) t n n Sensitive to the charged Higgs. n Theoretical systematics from the form factor. f. B in case of t n n Additional information from t polarization. c b H+/W+ t+ nt Decay amplitude Tauonic decay is the most sensitive ! Belle has observed B 0 D*-t+n ! 25
B D* t n: Reconstruction from K. -F. Cheng’ talk @ FPCP 07 2007/6/21 Toru ijima, SUSY 2010's 26
B D* t n: Results 2007/6/21 Toru ijima, SUSY 2010's 27
Cross Checks t enn Mtag >5. 27 signal na i lim background ry e Pr Mtag >5. 275 t pn Mtag <5. 26 signal Fit to signal side variable 2007/6/21 Toru ijima, SUSY 2010's other D*tn background cosqn 1 n 2 28
Tree 3: Future Prospect, Super-B The Road to NP 2007/6/21 Toru ijima, SUSY 2010's 29
Super-B: Motivation n If new physics at O(1)Te. V… – It is natural to assume that the effects are seen in B/D/t decays. – New source of CP violation ? – Flavour structure of new physics? – These studies will be useful to identify mechanism of SUSY breaking, if NP=SUSY. n Otherwise… – Search for deviations from SM in flavor physics will be one of the best ways to find new physics. 2007/6/21 Toru ijima, SUSY 2010's 30
Physics Reach at Super-B Physics at Super B Factory (hep-ex/0406071) 5 ab-1 50 ab-1 n New CPV phase in b sqq n FCNC B Xs , B Xsll n Modes including n n CKM n t decays We are working to update the table.
Search for New CPV in b s Discovery region w/ 50 ab-1 |ASUSY/ASM|2 B g f. K 0, h’K 0, Ks. Ks projection for Super. KEKB qnew physics 2007/6/21 Toru ijima, SUSY 2010's 32
Acp(B Xsg) vs SUSY models 5 ab-1 50 ab-1 Mixing CPV m. SUGURA tanb=30 SU(5)+n. R tanb=30 degenerate U(2) tanb=30 Acpmix Acpdir Direct CPV m. SUGURA tanb=30 SU(5)+n. R tanb=30 non-degenerate U(2) tanb=30 SU(5)+n. R tanb=30 non-degenerate
Charged Higgs Search in B tn Charged Higgs Mass Reach (95. 5%CL exclusion @ tanb=30) W+ Only exp. error (DVub=0%, Df. B=0%) t+ DVub=2. 5%, Df. B=2. 5% Now 5 ab-1 Mass Reach (Ge. V) DVub=5%, Df. B=5% Luminsoity(ab-1)
LFV in t Decays n Quarks and neutrinos have mixings. t l What about charged leptons ? n What are the relations between neutrinos and charged leptons ? t 3 l, lh quarks and charged leptons ? n Br(t) = O(103 -5) x Br(m). Enough chance to see t m or t lll. n The two decays have different sensitivity for different NP models. 2007/6/21 Toru ijima, SUSY 2010's 35
T LFV Prospect n Br~O(10 -8 9) at Super B factory ! t mh t mmm t m suffers from background due to ISR.
Super-KEKB Interaction Region Crab crossing q=30 mrad. by*=3 mm New QCS New Beam pipe 8 Ge. V (e+, 4. 1 A) 3. 5 Ge. V (e-, 9. 6 A) More RF power Damping ring Increase beam currents • 1. 6 A (LER) / 1. 2 A (HER) → 9. 4 A (LER) / 4. 1 A (HER) Smaller by* • 6 mm→ 3 mm Increase xy • 0. 059→>0. 24(W-S) L=8 x 1035 cm-2 s-1 Linac upgrade
Super-KEKB (cont’d) n Head-on collision w/ Crab cavity New crab cavity Will be tested in 2006. n Ante-chamber /solenoid for reduction of electron clouds Ante-chamber Circular-chamber Ante-chamber with solenoid field Build-up of electron clouds
Crab Cavity n Superconducting crab cavities (1 LER and 1 HER) have been installed, and being tested at KEKB. 2007/6/21 Toru ijima, SUSY 2010's 39
HER LER Crab OFF Crab ON H. Ikeda, et al.
Detector Upgrade 4 Issues Vertexing Pixel det. u. Higher background - radiation damage and occupancy 4 Small cell Fast gas Si-tracker - fake hits and pile-up noise in the EM u. Higher event rate - higher rate trigger, DAQ and computing u. Require special features - low p m identification - full recon. eff. - hermeticity ; n “reconstruction” 4 4 Fully pipelined readout Large scale computing New Challenge! Intensive R&Ds! Tracking 4 Particle ID F-DIRC+TOP Aerogel RICH 4 EM Cal Pure Cs. I Liquid-Xe etc. 4 KL & m LST Scintillator
Belle Upgrade SC solenoid 1. 5 T Cs. I(Tl) 16 X 0 g pure Cs. I (endcap) m / KL detection 14/15 lyr. RPC+Fe g tile scintillator Aerogel Cherenkov counter + TOF counter g “TOP” + RICH Tracking + d. E/dx small cell + He/C 2 H 5 gremove inner lyrs. Use fast gas New readout and computing systems 2007/6/21 Si vtx. det. 4 lyr. DSSD g 2 pixel/striplet lyrs. + 4 lyr. DSSD Toru ijima, SUSY 2010's 42
Summary n B-factories have been so successful. KM-model of CP violation firmly established. Paradigm shifted to search for NP effects. n We are starting to measure B tn/D(*)tn Search for charged Higgs. n Flavor physics still on the center stage in 2010’s. Super-KEKB enables us to study effects of Te. Vscale NP in B and t decays. 2007/6/21 Toru ijima, SUSY 2010's 43
Pushing Luminosity Frontier n L*=X 10 / 5 years ! BOYS BE AMBITIOUS ! L~1035 cm-2 s-1 by 2010 L~1036 cm-2 s-1 by 2015 L~1043 cm-2 s-1 by 2050 ? (How old will you be ? )
Backup Slides
f 2: B pp/rp/rr FPCP 2007 Beauty 2006 Two solutions in the global CKM fit. Need more data. 2007/6/21 Toru ijima, SUSY 2010's 46
ACP(Kp) puzzle ? ACP(K+p 0) = +0. 047 0. 026 ACP(K+p-) = -0. 093 0. 015 deviation: 0. 14/0. 03 > 4. 6 s New physics ?
B D* t n: Bkg. Suppression 2007/6/21 Toru ijima, SUSY 2010's 48
f. B Extraction n SM branching fraction is given by n Product of B meson decay constant f. B and CKM matrix element |Vub| n Using |Vub| = (4. 39 0. 33)× 10 -3 from HFAG 15% 14% = 12%(exp. ) + 8%(Vub) f. B = 216 22 Me. V 2007/6/21 [HPQCD, Phys. Rev. Lett. 95, 212001 (2005) ] Toru ijima, SUSY 2010's 49
B D* t n: Bkg. Suppression 2007/6/21 Toru ijima, SUSY 2010's 50
Future prospect n Possible sensitivity at 5 ab-1 PDG 2006 Belle Babar based on eff. and NBG of most sensitive analysis Estimated upper limit range of Br
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