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LCPAC 2006 Status Report. collaboration. S.L. Olsen U. of Hawai’i. KEK B-factory. Highest possible grade. 2 consecutive years. Sekkyokuteki suishin “push aggressively”. Publications. 164 journal papers published or submitted All reporting important, high impact results
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LCPAC 2006 Status Report collaboration S.L. Olsen U. of Hawai’i
KEK B-factory Highest possible grade 2 consecutive years Sekkyokuteki suishin “push aggressively”
Publications • 164 journal papers published or submitted • All reporting important, high impact results • ~42 papers submitted since LCPAC-2005 • ~9 currently in “authorship confirmation” • …
Notable recent results • Observation of bdg • Evidence for BKK • Large direct CPV in B+K+r0 decays • Observation of a FB asymm in BK*l+l- • Observation of a cc1’ candidate in ggDD • A new charmonium-like state, X(3940) • New csu baryons, Xcx(2980) and Xcx(3077) • …
Collaboration is stable Withdrawals: New members: • Institutions: • Nat’l Kaohsiung Normal U. • Utkal University • Aomori University • Tsukuba University • ~30 individuals • Institutions: • Illinois • Nova Gorica Inst, • Slovenia • ~40 individuals
Spokesperson changes Old New!! Aihara Olsen Browder Yamauchi Iijima Yamauchi New spokespersons all ran on platforms promising major reorganization of Belle ふにきがいれ, ぉにがそと
SVD-2 team continue their heroics Belle’s long march SVD2
SVD performance A.Kibayashi 4 layers + improved coverage better tracking effic
Quick fix Solder wires directly to the repeater board (connector established outside the detector during this past month) Beam off: 10/20 Resume Data taking 11/4 more details from Uno-san
~10% ~4% ~2% ~2% SVD Occupancy Present : layer 1 of SVD ~10%occupancy / 200 Krad.yr-1 SVD2 Need to upgrade the inner layers: SVD2.5 L~1.6x1034 → L~5x1034 cm-2s-1 ???
Tracking continues to improve 3xBkg Pt resolution (s in %) (Bp+p-: s(DE)21MeV) Standard track finder 0.3% Tracking effic.improvements: +7% for J/y KS; +60% for D*+D*- New “Global” track finder
…as does p0detection p0gg line shape Data vs MC M(p0) resolution (s in MeV) (Bp0p0: sM(p0)8MeV) 4.5MeV 100MeV 1 GeV p0 detection effic is sensitive to bkg conditions; ECL recon code.is being improved
Particle ID performance remains high ~87% ACC dead tubes ~8% Last yr
DAQ and computing are still keeping upalbeit just barely Faster signal processing with CMS chip in SVD (Silcon vertex det.) w/o Event Builder Upgrade New pipelined data Acquisition system (COPPER) Present operation Plan to implement this on the CDC this summer
We have a new computing system Katayama’s talk this afternoon 1200 Dell servers
The Belle Physics Program 1)Measure of Fundamental SM Params: CKM elements & phases 2)Search for New Physics: look for evidence of new particles in loops 3) Unanticipated new phenomena: large s(e+e-cccc), X(3872),X(3940),Y(3940),.. 4) + lots of “bread & butter” hc’, cc2’, D**,Sc*, Xcx,t-physics, spin frag-fcn,… I can only give a few small tastes from this rich & flavorful menu
_ B0 tag B0 J/y K0 sin2f1= 0.652 ±0.039 (stat) ±0.020 (syst) A = 0.010 ±0.026 (stat) ±0.036 (syst) B0 tag Precision measurement well understood method
2005 results: Bkg subtracted B+ - projections B0 tagged B0 tagged 4s signal for Direct CPV p+p− Yield p+p− ACP & DE-Mbc 2D fits to individual time intervals Dt (ps)
2005: Status of B+ - App Belle 275M Spp BABAR 227M ~2.3s difference between Belle and BABAR - App (Cpp ) Spp
Belle’s measurement of ACP(B0 0 ) Chao, Chang et al, PRL 94 181803 275M BBbar pairs
CPV in B0r+r Similar to Bp+p, but in principle more complicated … B VV: not a single CP eigenstate r+p+p0: wide resonance, two0’sin the final state. Three miracles: fL ~ 100% CP » +1 B()NR and int. small B(r0r0) << B(r+r), B(r+r0) < 1.1 30 6 (26 6 ) x 10-6(HFAG Winter05) 2q A+-/ 2 small Penguin pollution (q ) A00 A+0
Somov, Schwartz et al hep-ex/0601024 CPV in B+- (274 106 BB pairs) q=1 q=-1 Results: Low quality tag High quality tag No CPV φ2 is near 900
Belle Constraints on 2 (α) B [hep-ex/0502035] & combined at 90% CL
s u K+ W u c Vcb D0 s u u + d + d B B Vub D0 * VudVub b b 2(a) * c Vtd Vtb Vus Vcs W K+ 3(g) 1(b) u u Vcd Vcb * f3 () measurement Simple mixing CPV f3 (withBd ) + Tree Tree fCOM _ fCOM O(l3) O(l3) Interference of bc and bu diagrams
r r Belle method for f3: Dalitz Poluektov, Bondar et al hep-ex/0504013 3) fCOM= D0KSp+p- B+: obtain from tagged D0 (D*+ D0p+) sample |A2| |A1| B-: r = CPV: Asymmetry in Dalitz dist.: m+=m(Ksp+), m-=m(Ksp-)
Constraints of the Unitarity Triangle World average as of summer 2005 from GLW, ADS, Dalitz and sin(2φ1+φ3): γ/φ3=70 -14° +12 Simplistic(?) summation: f1+ f2+ f3 182o ~20o
CP angles only ? f1~70o Disfavored >2s sin2f1 f1~20o f1 2-fold ambiguity 2f1 p-2f1 Ambiguity removed by Dalitz analysis of B0D0(Kspp)h0 Krokovny etal hep-ex/0507065 Simplistic(?) summation: f1+ f2+ f3 182o ~20o
* VudVub 2(a) * Vtd Vtb 3(g) 1(b) Vcd Vcb * How about the CKM triangle’s sides? Dmd & b d g b u ℓ-n & B- ℓ-n b c l n
Belle Inclusive |Vub| Limosani et al PLB 621, 28 Electron energy at endpoint • Pth = 1.9 GeV/c • Systematic limited • Hadronic and leptonic • invariant mass (Mx, q2) • Use full recon tag. • P+ also measured. Bizjak et al PRL 95, 141801 • Non-experimental error dominated by errors of shape function parameters. PDG 2002: (3.6 0.7) x 10-3
Bℓn Decay Search Measures fB|Vub|2 Upper limits at EPS05 SM prediction Btn search close to SM expectation Results with 450 fb-1 expected next month Ikado et al, hep-ex/0507034
signal qq K*g other B First Observation of bd Mohapatra. Nakao, Nishida et al hep-ex/0506079 _ Addresses the same physics issue as Bs- Bs mixing (future Tevatron RunII goal).
Current status CPV angles only: η=0.321±0.027 =0.193±0.57 sides only: η=0.342±0.022 =0.216±0.036
SM with KM ansatz works remarkably well for tree-level processes Next step: Look for new physics in penguin loops
_ Example: bsss Example: no KM phase f1 * Vtd (or h’, K+K-) , (h’, K+K- + B B 0 0 * Vtd f1 _ SM: sin2f1 =sin2f1 from BJ/y KS (bc c s) unless there are other, non-SM particles in the loop eff
hep-ex/0507037 (180±16) (78±13)
Significant CP Violation in a bs penguin mode!! Chen et al PRD 72012
>>all systematically below sin(2b) >>QCD corrections : sin2b(penguin)>sin2b(tree) Many bs modes were studied: recent QCD factorization estimates : [Beneke, hep-ph/0505075] [Cheng,Chua,Soni, hep-ph/0506268] sin2φ1(penguin)-sin2φ1(tree)
sin2f1(penguin) = 0.50 0.06 (HFAG’s “naïve average”) 0.4-
new physics in EW penguins? • AFB for B K*ℓ+ℓ- Interference btw and Z (loops with virtual t’s, W’s, & Z’s) AFB (Kℓ+ℓ -) = 0.09 0.14 (stat) AFB(K*ℓ+ℓ -) = 0.56 0.13 (stat) 3.4 s from 0 Ishikawa et al hep-ex/0603018
Not just beauty • Charm physics • Tau physics • Hadron spectroscopy • Charmed mesons & baryons • Charmonium states hc’ , cc1’ • Mystery states X(3872), X(3940), Y(3940) • Fragmentation functions • Bs • Dark matter search
D0-D0 mixing Zhang, Li et al hep-ex/0601029 Belle 2006 Shipsey @ DIF06
High precisiont-p-p0 nt Fujikawa, Hayashii et al hep-ex/0502171
bonuses: new mesons, many puzzles! Choi et al, PRL 89 112001 Choi et al , PRL 91 262001 Z(3931) cc2’? hc’ X(3872) Uehara et al , PRL 96 082003 Y(3940)wJ/y e+e-cccc Choi et al , PRL 94 182002 ?? Pakhlov et al , hep-ex/0507019 M(wJ/y) MeV
more bonuses: charmed baryons c+- c+0 c++ c0(2800) c++(2800) c+(2800) Mizuk et al PRL 94 122002 & mesons D0’0(2427) D0*(2308) Kuzmin et al PR D69 112002
CLEO PRL 54, 381 (5S) (5S) “engineering” rundetails from Alan Schwartz this PM (4S) 3-day, 1.86 fb-1 test run Bs*Bs* Mbc BsBs* BsBs 100% BqBq DE Bs(*)Bs(*) Bq(*)Bq(*) BqBq(*)π BqBqππ Bf(Bsgg)< 0.56 x 10-4 (90%CL) ~factor 3 improvement on on world best limit
DAMA NaI 3s Region CDMS 04 CDMS 05 Dark matter search McElrath, PRD 72, 103508: Br((1S)cc)~0.4% Mc < 4.7 GeV Experimental signature: (3S)pp(1s) pp nothing Belle (with optimized trigger): Direct dark-matter searches cannot see M<10 GeV region McElrath prediction 3fb-1 engineering run data @ the (3S) under analysis
Summary f3 error ~100 ?? B+t+n ?? cc2’ X(3940), Y(3940) bd penguins (bdg BKK) DD-mixing (world’s best limit) f2 error~100 |Vub| error <10% Sc* baryon triplet Direct CPV in BK+p- X(3872) BK*ℓ+ℓ- EW penguin D0*0 & D1*0 mesons CPV in B decays hc’ & e+e-cccc
Conclusion • The Belle collaboration remains strong • Our publishing is nearing 1 paper/week • We have two new & energetic spokespersons • Our detector continues to perform well • Continuously improvements to handle increased luminosity (&bkg) • We have shown that the CKM ansatz works well for tree processes • Verified with high precision • Provides “anchor point” for new physics searches • CPV in penguins provide us with sensitive probe for new physics • Theoretically and experimentally clean • We are measuring Bf~10-6 penguin processes with high precision • We have made a number of “unexpected discoveries” • And expect many more in the future