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 b  s penguin modes Measurement of CPV in B  p + p – See also Today A.Mihalyi “Recent results on the CKM angle α from BABAR” New method of the f 3 measurement in B  D 0 K based on Dalitz plot analysis of the three body D 0  K S p + p – decay See also Today M. Legendre “ Status and prospects for the measurement of angle γ ” T. Gershon “Measurement of φ 3 using B– to DK– with D to K s π+π–” DA  NE04 Frascati June 7, 2004

Coupling strength at decay vertex : g F V ij universal Fermi weak coupling : g F V ij : quark-mixing matrix elements CKM matrix : unitarity : V ji *V jk =d ik explicit parametrization (Wolfenstein) complex phase leads to different b  u and t  d amplitudes for quarks and anti-quarks. CP  ± A  0.81±0.08 |  i  |  0.36±0.09 |  i  |  0.79±0.19 The Weak Decays of Quarks quark decay g F V ij i j quark decay g F V ij * i j DA  NE04 Frascati June 7, 2004

The B Unitarity Triangle Using orthogonality relation   B 0  pp B 0  rp B 0  D (*) p B +  DK B 0  J/yK s B 0  fK s B 0  D ( * ) D ( * ) DA  NE04 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 ! DA  NE04 Frascati June 7, 2004

Time-dependent CP violation If either S or A is non-zero, B  f CP has CP asymmetry. Mixing induced CPV param. Direct CP violation param.  DA  NE04 Frascati June 7, 2004

KEKB & BELLE BELLE detector KEKB Collider ~350 scientists, 55 institutions 3.5GeV e + & 8GeV e - Asymmetric Collider 3km circumference, 11mrad crossing angle L= 1.3 x cm –2 s –1 (world record) L dt = 266 fb (140fb -1 : 1.52 x 10 8 ) DA  NE04 Frascati June 7, 2004

PEPII & BABAR BABAR Detector PEPII Collider 3GeV e + & 9GeV e - Asymmetric Collider L= 0.92 x cm –2 s –1 L dt = 214 fb Cherenkov Detector (DIRC) Silicon Vertex Tracker Instrumented Flux Return CsI(Tl) Calorimeter Superconducting Coil (1.5T) Drift Chamber e - (9 GeV) e + (3 GeV) DA  NE04 Frascati June 7, 2004

e-e- e+e+ e - :8.0 GeV e + :3.5 GeV B CP DzDz B tag ¡(4S) bg ~ f CP Dz  cbgt B ~ 200 mm Flavor tag 4 steps toward the CP violation measurement Reconstruct B  f CP decays Determine the flavor of B tag Measure proper-time interval : Dt Evaluate asymmetry from the obtained Dt distributions How to measure CP violation ? DA  NE04 Frascati June 7, 2004

hep-ex/ b  ccs sin2f 1 : b  ccs BaBar 81 fb -1 : sin(2φ 1 ) =0.741±0.067±0.033 DA  NE04 Frascati June 7, 2004

 J/   cos2f 1 from B  J/   Moriond04, M.Verderi

DA  NE04 Frascati June 7, 2004  J/   cos2f 1 from B  J/  

DA  NE04 Frascati June 7, 2004  J/   cos2f 1 from B  J/  

DA  NE04 Frascati June 7, 2004 Non-Standard-Model particles could appear in the penguin loop, modifying rate and/or CP asymmetry Non-Standard-Model particles could appear in the penguin loop, modifying rate and/or CP asymmetry In the SM, for pure b  s penguin transition modes sin2f 1 eff = sin2f 1 (B  J/yK S )

DA  NE04 Frascati June 7, 2004 L = 108 fb -1 hep-ex/

DA  NE04 Frascati June 7, 2004 L = 111 fb -1 BELLE PRD 60, (2004) hep-ex/

DA  NE04 Frascati June 7, 2004 sin2f 1 Summary

Points of B 0  π + π – decay sensitive to CKM angle  2 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. b u d B0B0  d W+W+  d B0B0 b d B0B0 d u u d   g t DA  NE04 Frascati June 7, 2004

Constraints on the CKM angle  2 4 parameters |P/T| (representative) Theory ~0.3  deg (Belle & BaBar combined) Strong phase difference convention taken from M.Gronau and J.L.Rosner Phys. Rev. D65, (2002) DA  NE04 Frascati June 7, 2004

b  uud      sin2f 2 : b  uud, B 0      High Quality Events Low Quality Events L = 140 fb -1

S  A  Significance Feldman-Cousins Analysis (5.2  Observation of CP violation  3.2  for A  =0 and any S  Evidence for direct CP violation 3.3  for “superweak” case hep-ex/ DA  NE04 Frascati June 7, 2004

History of A  and S  Belle BaBar This result Belle 140fb  1 Difference still at ~2.0  level DA  NE04 Frascati June 7, 2004

Constraint on  2 and |P/T| Belle 140fb  1 11 22 33 |P/T| > 0.17 [95.5% C.L. (  2  )]  2 (deg.)  (deg.)  2 (deg.) 33 22 11 90  ≤  2 ≤ 146  (95.5% CL) |P/T| =0.3 |P/T| |P|/(|T|+|P|) DA  NE04 Frascati June 7, 2004

b  uud      sin2f 2 : b  uud, B 0     

DA  NE04 Frascati June 7, 2004   D (*)0 K     measurement, B   D (*)0 K 

DA  NE04 Frascati June 7, 2004   D (*)0 K     measurement, B   D (*)0 K  ρ-ω interference Doubly Cabibbo suppressed K * Construct f as sum of known two-body resonances plus non- resonant term, fit to continuum D*-to-D-to-Kππ data.

DA  NE04 Frascati June 7, 2004   D (*)0 K     measurement, B   D (*)0 K  L = 140 fb events

B +  D ( * )0 K + fit result r + =0.40±0.15, θ + =256±19° r - =0.21±0.15, θ - = 71±37° B +  D 0 K + B +  D* 0 K + r + =0.29±0.19, θ + =353±38° r - =0.38±0.19, θ - =249±32° DA  NE04 Frascati June 7, 2004

  D (*)0 K     measurement, B   D (*)0 K  Combined fit:

DA  NE04 Frascati June 7, 2004  Conclusion Belle and BaBar continue to refine their measurements of from ccs modes. _ _ 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. today this summer in two years? ? 140fb fb -1 >500fb -1

DA  NE04 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!

CP eigenstates categoryCP modeprocessCP(x f )SM prediction SAPenguin charmoniumJ/y KSJ/y KS - x f sin2f 1 0negligible y(2S) K S c C1 K S hC KShC KS J/y K*(K S p 0 ) -1/+1 J/y KLJ/y KL +1 charmoniumJ/y p0J/y p x f sin2f 1 eff yes double charmD (*) -1/+1smallyes b  s penguinf KSf KS - x f sin2f 1 smalldominant h’ K S K+K-KSK+K-KS +1 hhp+p-p+p x f sin2f 2 eff yes (x f  CP eigenvalue) DA  NE04 Frascati June 7, 2004

Continuous Injection

b  uud sin2f 2 : b  uud Time-dependent CP asymmetries in B 0  π + π – -- the best way to access the CKM angle  2  = +1 for B 0 tag  1 for B 0 tag direct CP asymmetry  t=  z/(  c) z z DA  NE04 Frascati June 7, 2004

b  uud      sin2f 2 : b  uud, B 0     

DA  NE04 Frascati June 7, 2004 b  uud      sin2f 2 : b  uud, B 0      L = 113 fb -1