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CP VIOLATION at B-factories. A.Bondar (Budker INP,Novosibirsk). Measurements of large CPV in b c c s modes Search for New Physics: CPV in bs penguin modes Measurement of CPV in B p + p – See also Today A.Mihalyi “ Recent results on the CKM angle α from BABAR ”
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CP VIOLATION at B-factories A.Bondar (Budker INP,Novosibirsk) Measurements of large CPV in bc c s modes Search for New Physics: CPV in bs penguin modes Measurement of CPV in Bp+p – See also Today A.Mihalyi “Recent results on the CKM angle α from BABAR” New method of the f3 measurement in BD0K based on Dalitz plot analysis of the three body D0KSp+p –decay See also Today M. Legendre “Status and prospects for the measurement of angle γ” T. Gershon “Measurement of φ3 using B– to DK– with D to Ksπ+π–” DAFNE04 Frascati June 7, 2004
quark decay i gFVij j quark decay i gFVij* j CP • l = 0.2235±0.0033A =0.81±0.08 |r-ih|=0.36±0.09 |1-r-ih|= 0.79±0.19 The Weak Decays of Quarks • Coupling strength at decay vertex : gFVij • universal Fermi weak coupling : gF • Vij : quark-mixing matrix elements • CKM matrix : • unitarity : Vji*Vjk=dik • explicit parametrization (Wolfenstein) • complex phase leads to different bu and td amplitudes for quarks and anti-quarks. DAFNE04 Frascati June 7, 2004
B0 pp B0rp (a) B0 D(*)p B+DK (g) (b) B0 J/yKs B0fKs B0D(*)D(*) The B Unitarity Triangle Using orthogonality relation DAFNE04 Frascati June 7, 2004
CKM CP phenomenology • CP violation arises from the interference of two amplitudes with different phases. • Mixing induced CP violation : Indirect CPV • Decay amplitudes asymmetry: Direct CPV • Single CKM phase = unique source of CPV ? • It is difficult for CKM CPV to explain the observed matter/antimatter asymmetry in the universe. • It is needed to search for Beyond SM ! DAFNE04 Frascati June 7, 2004
Direct CP violation param. z Mixing induced CPV param. Time-dependent CP violation If either S or A is non-zero, B fCP has CP asymmetry. DAFNE04 Frascati June 7, 2004
BELLE detector ~350 scientists, 55 institutions KEKB & BELLE KEKB Collider 3.5GeV e+ & 8GeV e-Asymmetric Collider 3km circumference, 11mrad crossing angle • L= 1.3 x 1034 cm–2s–1 (world record) Ldt = 266 fb–1 @{Y(4S)+off(~10%)} (140fb-1 : 1.52 x 108 ) DAFNE04 Frascati June 7, 2004
e- (9 GeV) PEPII & BABAR e+ (3 GeV) PEPII Collider BABAR Detector Superconducting Coil (1.5T) 3GeV e+ & 9GeV e-Asymmetric Collider L= 0.92 x 1034 cm–2s–1 Ldt = 214 fb–1 @{Y(4S)+off(~10%)} Silicon Vertex Tracker Drift Chamber CsI(Tl) Calorimeter Cherenkov Detector (DIRC) Instrumented Flux Return DAFNE04 Frascati June 7, 2004
How to measure CP violation ? BCP e-: 8.0 GeV e+: 3.5 GeV fCP e- e+ ¡(4S) bg ~ 0.425 DzcbgtB ~ 200 mm Btag Flavor tag Dz • 4 steps toward the CP violation measurement • Reconstruct BfCP decays • Determine the flavor of Btag • Measure proper-time interval : Dt • Evaluate asymmetry from the obtained Dt distributions DAFNE04 Frascati June 7, 2004
sin2f1 :bccs hep-ex/0308036 BaBar 81 fb-1: sin(2φ1) =0.741±0.067±0.033 DAFNE04 Frascati June 7, 2004
cos2f1 from B J/y(Kp)0 Moriond04, M.Verderi DAFNE04 Frascati June 7, 2004
cos2f1 from B J/y(Kp)0 DAFNE04 Frascati June 7, 2004
cos2f1 from B J/y(Kp)0 DAFNE04 Frascati June 7, 2004
In the SM, for pure bs penguin transition modes sin2f1eff = sin2f1(BJ/yKS) Non-Standard-Model particles could appear in the penguin loop, modifying rate and/or CP asymmetry DAFNE04 Frascati June 7, 2004
L = 108 fb-1 hep-ex/0406005 DAFNE04 Frascati June 7, 2004
L = 111 fb-1 hep-ex/0406005 BELLE PRD 60, 012001(2004) DAFNE04 Frascati June 7, 2004
sin2f1 Summary DAFNE04 Frascati June 7, 2004
p+ d W+ b u p- B0 d d B0 d b p+ t u g B0 u p- d d Points of B0 π+π–decay • sensitive to CKM angle f2 • direct CP violation may also occur because of interference between • b u tree amplitude and • b d penguin amplitude • It’s very important to check the KM matrix by other measurements. DAFNE04 Frascati June 7, 2004
Constraints on the CKM angle f2 convention taken from M.Gronau and J.L.Rosner Phys. Rev. D65, 093012 (2002) 4 parameters Strong phase difference |P/T| 0.15-0.45 (representative) Theory ~0.3 f1 23.7 deg (Belle & BaBar combined) DAFNE04 Frascati June 7, 2004
L = 140 fb-1 High Quality Events Low Quality Events sin2f2 : buud,B0p+p- DAFNE04 Frascati June 7, 2004
Observation of CP violation (5.2s) Evidence for direct CP violation 3.2s for App=0 and any Spp App 3.3s for “superweak” case Spp Significance Feldman-Cousins Analysis hep-ex/0401029 DAFNE04 Frascati June 7, 2004
History ofAppand Spp Belle This result Belle 140fb1 BaBar Difference still at ~2.0s level DAFNE04 Frascati June 7, 2004
Belle 140fb1 Constraint onf2and|P/T| |P/T| 3s 3s 1s 2s 2s 1s f2 (deg.) f2 (deg.) |P|/(|T|+|P|) d (deg.) |P/T| > 0.17 [95.5% C.L. ( 2s)] 90 ≤ f2≤ 146 (95.5% CL) |P/T| =0.3 DAFNE04 Frascati June 7, 2004
sin2f2 : buud,B0p+p- DAFNE04 Frascati June 7, 2004
f3measurement, B-D(*)0K- DAFNE04 Frascati June 7, 2004
Doubly Cabibbo suppressed K* ρ-ω interference f3measurement, B-D(*)0K- Construct f as sum of known two-body resonances plus non-resonant term, fit to continuum D*-to-D-to-Kππ data. DAFNE04 Frascati June 7, 2004
L = 140 fb-1 73 events 73 events f3measurement, B-D(*)0K- DAFNE04 Frascati June 7, 2004
B+ D(*)0K+fit result B+ D0K+ B+ D*0K+ r+=0.29±0.19, θ+=353±38° r- =0.38±0.19, θ- =249±32° r+=0.40±0.15, θ+=256±19° r- =0.21±0.15, θ- = 71±37° DAFNE04 Frascati June 7, 2004
Combined fit: f3measurement, B-D(*)0K- DAFNE04 Frascati June 7, 2004
Belle and BaBar continue to refine their measurements of from ccs modes. _ Conclusion Both experiments are using their high-luminosity data samples to probe for new physics in rare B decays: over-constrain the sides and angles of the Unitarity Triangle. 140fb-1 270fb-1 >500fb-1 today this summer in two years? ? DAFNE04 Frascati June 7, 2004
Conclusion Many new/updated results utilizing ~230–280 fb-1 of data per experiment will be shown this summer. Watch this space! DAFNE04 Frascati June 7, 2004
CP eigenstates (xf CP eigenvalue) DAFNE04 Frascati June 7, 2004
Continuous Injection DAFNE04 Frascati June 7, 2004
z= +1 for B0 tag 1 for B0 tag sin2f2 : buud Time-dependent CP asymmetries in B0 π+π– -- the best way to access the CKM angle f2 z z Dt=Dz/(bgc) direct CP asymmetry DAFNE04 Frascati June 7, 2004
sin2f2 : buud,B0r+r- DAFNE04 Frascati June 7, 2004
L = 113 fb-1 sin2f2 : buud,B0r+r- DAFNE04 Frascati June 7, 2004