Small amplitude effects in B{sup 0}{yields}D{sup +}D{sup -} and related decays

Journal Article · Fri Aug 01 04:00:00 EDT 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.033011· OSTI ID:21250601

Gronau, Michael; Rosner, Jonathan L; Pirjol, Dan ^[1]

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1. Enrico Fermi Institute and Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States)

Intrigued by a recent Belle result for a large direct CP asymmetry in B{sup 0}{yields}D{sup +}D{sup -}, we study the effects of a b{yields}uud quark transition by combining the asymmetry information with rates and asymmetries in isospin-related decays. Arguing for a hierarchy among several contributions to these decays, including an exchange amplitude which we estimate, we present tests for factorization of the leading terms, and obtain an upper bound on the ratio of b{yields}uud and b{yields}ccd amplitudes. We prove an approximate {delta}I=1/2 amplitude relation for B{yields}DD, and an approximate equality between CP asymmetries in B{sup 0}{yields}D{sup +}D{sup -} and B{sup +}{yields}D{sup +}D{sup 0}. Violations of these relations by Belle measurements, at 1.8{sigma} and 3.6{sigma} respectively, if confirmed, would indicate a possible new physics contribution in b{yields}uud. Applying flavor SU(3), we extend this study to a total of ten processes, including {delta}S=0 decays involving final D{sub s} and initial B{sub s} mesons, and {delta}S=1 decays of B and B{sub s} mesons into pairs of charmed pseudoscalar mesons. The decays B{sub s}{yields}DD provide useful information about a small exchange amplitude, responsible for a decay rate difference between B{sup +}{yields}D{sup +}D{sup 0} and B{sup 0}{yields}D{sup +}D{sup -}. A method for determining the weak phase {gamma}, based on CP asymmetries in B{sup 0}(t){yields}D{sup +}D{sup -} and the decay rate for B{sub s}{yields}D{sub s}{sup +}D{sub s}{sup -} or B{sup +(0)}{yields}D{sub s}{sup +}D{sup 0}(D{sup -}), is shown to involve high sensitivity to SU(3) breaking.

• OSTI ID: 21250601
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 3 Vol. 78; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
ASYMMETRY
B NEUTRAL MESONS
D MINUS MESONS
D NEUTRAL MESONS
D PLUS MESONS
D S MESONS
FACTORIZATION
FLAVOR MODEL
ISOSPIN
PARTICLE DECAY
QUARKS
SENSITIVITY
SU-3 GROUPS
SYMMETRY BREAKING