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Title: CKM Angles {alpha}({phi}2) and {gamma}({phi}3)

Abstract

The results of the measurements of angles {alpha}({phi}2) and {gamma}({phi}3) of the Unitarity Triangle are reviewed. Using currently available measurements, the world averages are {phi}{sub 2} = [99{sub -17}{sup +12}] deg. and {phi}{sub 3} = [63{sub -13}{sup +15}] deg., which are quite consistent with {phi}1 + {phi}2 + {phi}3 = 180 deg., together with rather precisely measured {phi}{sub 1} = [21.7{sub -1.2}{sup +1.3}] deg.

Authors:
 [1]
  1. KEK, 1-1, Oho, Tsukuba, Ibaraki, 305-0801 (Japan)
Publication Date:
OSTI Identifier:
20798032
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 815; Journal Issue: 1; Conference: 25. international conference on physics in collision, Prague (Czech Republic), 5-9 Jul 2005; Other Information: DOI: 10.1063/1.2173582; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CP INVARIANCE; KOBAYASHI-MASKAWA MATRIX; STANDARD MODEL; UNITARITY; WEAK INTERACTIONS; WEINBERG ANGLE

Citation Formats

Sakai, Yoshihide. CKM Angles {alpha}({phi}2) and {gamma}({phi}3). United States: N. p., 2006. Web. doi:10.1063/1.2173582.
Sakai, Yoshihide. CKM Angles {alpha}({phi}2) and {gamma}({phi}3). United States. doi:10.1063/1.2173582.
Sakai, Yoshihide. Wed . "CKM Angles {alpha}({phi}2) and {gamma}({phi}3)". United States. doi:10.1063/1.2173582.
@article{osti_20798032,
title = {CKM Angles {alpha}({phi}2) and {gamma}({phi}3)},
author = {Sakai, Yoshihide},
abstractNote = {The results of the measurements of angles {alpha}({phi}2) and {gamma}({phi}3) of the Unitarity Triangle are reviewed. Using currently available measurements, the world averages are {phi}{sub 2} = [99{sub -17}{sup +12}] deg. and {phi}{sub 3} = [63{sub -13}{sup +15}] deg., which are quite consistent with {phi}1 + {phi}2 + {phi}3 = 180 deg., together with rather precisely measured {phi}{sub 1} = [21.7{sub -1.2}{sup +1.3}] deg.},
doi = {10.1063/1.2173582},
journal = {AIP Conference Proceedings},
number = 1,
volume = 815,
place = {United States},
year = {Wed Feb 08 00:00:00 EST 2006},
month = {Wed Feb 08 00:00:00 EST 2006}
}
  • The author reports on the experimental studies of the CKM unitarity angles {alpha}({phi}{sub 2}) and {gamma}({phi}{sub 3}) with emphasis on recent measurements by the Bell and Babar experiments at the B-factory accelerators.
  • Measurements of the modes B {yields} {pi}{pi} and B {yields} {rho}{rho} and their implications on the angle a of the CKM unitarity triangle are presented. Results of the Dalitz analysis of the modes B {yields} D(*)0K(*) and the derived constraints on the angle {gamma} are then shown. These measurements are based on a sample of approximately 230.106 B pairs taken at the {upsilon}(4S) resonance collected by the BABAR detector at the PEP-II asymmetric-energy beam factory at SLAC.
  • We present recent measurements of the CP violating angle {gamma}/ {phi}3 ({gamma} notation will be used) performed by the BABAR and BELLE collaborations. Measurements with B{+-}{yields}D(*)0K(*){+-} decays of charged B mesons exploit the Gronau-London-Wyler (GLW), Atwood-Dunietz-Soni (ADS) and Giri-Grossman-Soffer-Zupan (GGSZ) methods. The GGSZ method provides the strongest constrain; BABAR, using 227x106 BB(bar sign) pairs, reports {gamma} = 67 deg. {+-} 28 deg. (stat.) {+-} 13 deg. (syst.) {+-} 11 deg. (Dalitz model) and BELLE measures, with 386x106 BB(bar sign) pairs, {gamma} = 53 deg. {sub -18}{sup +15} deg. (stat.) {+-} 3 deg. (syst.) {+-} 9 deg. (Dalitz model). Measurements withmore » neutral B decays are based on time-dependent analyses of B0{yields}D(*)-{pi}+, D-{rho}+ decays. BABAR obtains |sin(2{beta}+{gamma})|>0.64(0.40) at 68(90)% CL using 232x106 BB-bar pairs and BELLE, with 386x106 BB(bar sign) pairs, reports vertical bar sin(2{beta}+{gamma}) vertical bar >0.44(0.13) at 68(95)% CL for D*{pi} and vertical bar sin(2{beta}+{gamma}) vertical bar >0.52(0.07) at 68(95)% CL for D{pi} . Searches for other decay modes useful for the {gamma} measurement are reported. BABAR observes the allowed B-bar0 {yields} D0K-bar*0 decay, but not the suppressed B-bar0 {yields} D-bar0K-bar*0 one. This translates to the limit on the ratio of the suppressed to allowed amplitudes rB < 0.4 at 90% CL.« less
  • We exploit the quantum coherence between pair-produced D{sup 0} and D{sup 0} in {psi}(3770) decays to make a first determination of the relative strong phase differences between D{sup 0}{yields}K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} and D{sup 0}{yields}K{sub S}{sup 0}{pi}{sup +}{pi}{sup -}, which are of great importance in determining the Cabibbo-Kobayashi-Maskawa angle {gamma}/{phi}{sub 3} in B{sup -}{yields}D{sup 0}(D{sup 0})K{sup -} decays. Using 818 pb{sup -1} of e{sup +}e{sup -} collision data collected with the CLEO-c detector at E{sub cm}=3.77 GeV, we employ a binned Dalitz-plot analysis of K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub L}{sup 0}{pi}{sup +}{pi}{sup -} decays recoiling against flavor-tagged,more » CP-tagged, and K{sub S}{sup 0}{pi}{sup +}{pi}{sup -}-tagged events to determine these strong phase differences.« less
  • In this report we summarize the most recent results of measurements of the angle {gamma}/{phi}{sub 3} of the Unitarity Triangle.