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Title: Evidence for CP Violation in B{sup 0}{yields}D{sup +}D{sup -} Decays

Abstract

We report measurements of the branching fraction and CP violation parameters in B{sup 0}{yields}D{sup +}D{sup -} decays. The results are based on a data sample that contains 535x10{sup 6} BB pairs collected at the {upsilon}(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider. We obtain [1.97{+-}0.20(stat){+-}0.20(syst)]x10{sup -4} for the branching fraction of B{sup 0}{yields}D{sup +}D{sup -}. The measured values of the CP violation parameters are S=-1.13{+-}0.37{+-}0.09, A=0.91{+-}0.23{+-}0.06, where the first error is statistical and the second is systematic. We find evidence of CP violation in B{sup 0}{yields}D{sup +}D{sup -} at the 4.1{sigma} confidence level. While the value of S is consistent with expectations from other measurements, the value of the parameter A favors large direct CP violation at the 3.2{sigma} confidence level, in contradiction to standard model expectations.

Authors:
; ; ; ; ; ;  [1]; ; ; ; ; ; ; ; ; ; ; ; ;  [2]
  1. J. Stefan Institute, Ljubljana (Slovenia)
  2. High Energy Accelerator Research Organization (KEK), Tsukuba (Japan) (and others)
Publication Date:
OSTI Identifier:
20951442
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 22; Other Information: DOI: 10.1103/PhysRevLett.98.221802; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; B NEUTRAL MESONS; BRANCHING RATIO; CP INVARIANCE; D MINUS MESONS; D PLUS MESONS; PAIR PRODUCTION; PARTICLE DECAY; STANDARD MODEL

Citation Formats

Fratina, S., Bitenc, U., Bizjak, I., Gorisek, A., Pestotnik, R., Staric, M., Zupanc, A., Abe, K., Adachi, I., Haba, J., Hazumi, M., Itoh, R., Iwasaki, Y., Katayama, N., Kichimi, H., Krokovny, P., Limosani, A., Nakao, M., Nishida, S., and Ozaki, H. Evidence for CP Violation in B{sup 0}{yields}D{sup +}D{sup -} Decays. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.221802.
Fratina, S., Bitenc, U., Bizjak, I., Gorisek, A., Pestotnik, R., Staric, M., Zupanc, A., Abe, K., Adachi, I., Haba, J., Hazumi, M., Itoh, R., Iwasaki, Y., Katayama, N., Kichimi, H., Krokovny, P., Limosani, A., Nakao, M., Nishida, S., & Ozaki, H. Evidence for CP Violation in B{sup 0}{yields}D{sup +}D{sup -} Decays. United States. doi:10.1103/PHYSREVLETT.98.221802.
Fratina, S., Bitenc, U., Bizjak, I., Gorisek, A., Pestotnik, R., Staric, M., Zupanc, A., Abe, K., Adachi, I., Haba, J., Hazumi, M., Itoh, R., Iwasaki, Y., Katayama, N., Kichimi, H., Krokovny, P., Limosani, A., Nakao, M., Nishida, S., and Ozaki, H. Fri . "Evidence for CP Violation in B{sup 0}{yields}D{sup +}D{sup -} Decays". United States. doi:10.1103/PHYSREVLETT.98.221802.
@article{osti_20951442,
title = {Evidence for CP Violation in B{sup 0}{yields}D{sup +}D{sup -} Decays},
author = {Fratina, S. and Bitenc, U. and Bizjak, I. and Gorisek, A. and Pestotnik, R. and Staric, M. and Zupanc, A. and Abe, K. and Adachi, I. and Haba, J. and Hazumi, M. and Itoh, R. and Iwasaki, Y. and Katayama, N. and Kichimi, H. and Krokovny, P. and Limosani, A. and Nakao, M. and Nishida, S. and Ozaki, H.},
abstractNote = {We report measurements of the branching fraction and CP violation parameters in B{sup 0}{yields}D{sup +}D{sup -} decays. The results are based on a data sample that contains 535x10{sup 6} BB pairs collected at the {upsilon}(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider. We obtain [1.97{+-}0.20(stat){+-}0.20(syst)]x10{sup -4} for the branching fraction of B{sup 0}{yields}D{sup +}D{sup -}. The measured values of the CP violation parameters are S=-1.13{+-}0.37{+-}0.09, A=0.91{+-}0.23{+-}0.06, where the first error is statistical and the second is systematic. We find evidence of CP violation in B{sup 0}{yields}D{sup +}D{sup -} at the 4.1{sigma} confidence level. While the value of S is consistent with expectations from other measurements, the value of the parameter A favors large direct CP violation at the 3.2{sigma} confidence level, in contradiction to standard model expectations.},
doi = {10.1103/PHYSREVLETT.98.221802},
journal = {Physical Review Letters},
number = 22,
volume = 98,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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