skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Measurements of the CKM Angle beta

Abstract

In this article I report on new and updated measurements of the CP-violating parameter {beta}({phi}{sub 1}), which is related to the phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix of the electroweak interaction. Over the past few years, {beta} has become the most precisely known parameter of the CKM unitarity triangle that governs the B system. The results presented here were produced by the two B Factories, BABAR and Belle, based on their most recent datasets of over 600 million B{bar B} events combined. The new world average for sin2{beta}, measured in the theoretically and experimentally cleanest charmonium modes, such as B{sup 0} {yields} J/{Psi}K{sub S}{sup 0}, is sin 2{beta} = 0.685 {+-} 0.032. In addition to these tree-level dominated decays, independent measurements of sin2{beta} are obtained from gluonic b {yields} s penguin decays, including B{sup 0} {yields} {phi}K{sub S}{sup 0}, B{sup 0} {yields} {eta}'K{sub S}{sup 0} and others. There are hints, albeit somewhat weaker than earlier this year, that these measurements tend to come out low compared to the charmonium average, giving rise to the tantalizing possibility that New Physics amplitudes could be contributing to the corresponding loop diagrams. Clearly, more data from both experiments are needed to elucidate thesemore » intriguing differences.« less

Authors:
;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
877494
Report Number(s):
SLAC-PUB-11557
hep-ex/0511016; TRN: US0601512
DOE Contract Number:
AC02-76SF00515
Resource Type:
Conference
Resource Relation:
Conference: Talk given at 25th International Symposium on Physics in Collision (PIC 05), Prague, Czech Republic, 6-9 Jul 2005
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; CHARMONIUM; PHYSICS; UNITARITY; Experiment-HEP,HEPEX

Citation Formats

Bartoldus, Rainer, and /SLAC. Measurements of the CKM Angle beta. United States: N. p., 2005. Web.
Bartoldus, Rainer, & /SLAC. Measurements of the CKM Angle beta. United States.
Bartoldus, Rainer, and /SLAC. Wed . "Measurements of the CKM Angle beta". United States. doi:. https://www.osti.gov/servlets/purl/877494.
@article{osti_877494,
title = {Measurements of the CKM Angle beta},
author = {Bartoldus, Rainer and /SLAC},
abstractNote = {In this article I report on new and updated measurements of the CP-violating parameter {beta}({phi}{sub 1}), which is related to the phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix of the electroweak interaction. Over the past few years, {beta} has become the most precisely known parameter of the CKM unitarity triangle that governs the B system. The results presented here were produced by the two B Factories, BABAR and Belle, based on their most recent datasets of over 600 million B{bar B} events combined. The new world average for sin2{beta}, measured in the theoretically and experimentally cleanest charmonium modes, such as B{sup 0} {yields} J/{Psi}K{sub S}{sup 0}, is sin 2{beta} = 0.685 {+-} 0.032. In addition to these tree-level dominated decays, independent measurements of sin2{beta} are obtained from gluonic b {yields} s penguin decays, including B{sup 0} {yields} {phi}K{sub S}{sup 0}, B{sup 0} {yields} {eta}'K{sub S}{sup 0} and others. There are hints, albeit somewhat weaker than earlier this year, that these measurements tend to come out low compared to the charmonium average, giving rise to the tantalizing possibility that New Physics amplitudes could be contributing to the corresponding loop diagrams. Clearly, more data from both experiments are needed to elucidate these intriguing differences.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Dec 14 00:00:00 EST 2005},
month = {Wed Dec 14 00:00:00 EST 2005}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: