Observation of large CP violation in the neutral BB meson system

Collaboration
Jul, 2001
12 pages
Published in:
  • Phys.Rev.Lett. 87 (2001) 091802
e-Print:
Report number:
  • KEK-PREPRINT-2001-50,
  • BELLE-PREPRINT-2001-10
Experiments:

Citations per year

19982005201220192025050100150
Abstract: (arXiv)
We present a measurement of the Standard Model CP violation parameter sin 2phi_1 based on a 29.1 fb^{-1} data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. One neutral B meson is fully reconstructed as a J/psi Ks, psi(2S) Ks, chi_c1 Ks, eta_c Ks, J/psi K_L or J/psi K^{*0} decay and the flavor of the accompanying B meson is identified from its decay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we determine sin 2phi_1 = 0.99 +- 0.14(stat) +- 0.06(syst). We conclude that we have observed CP violation in the neutral B meson system.
Note:
  • 4 figures, to appear in Phys. Rev. Letters Report-no: KEK Preprint 2001-50, Belle Preprint 2001-10
  • electron positron: colliding beams
  • electron positron: annihilation
  • Upsilon(10570): electroproduction
  • B: pair production
  • B: hadronic decay
  • anti-B0: hadronic decay
  • CP: violation
  • time dependence
  • CKM matrix: unitarity
  • charmonium