Effects of final-state interactions on mixing-induced CP violation in penguin-dominated B decays

Journal Article · Fri Jul 01 04:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.014006· OSTI ID:20711048

Cheng, H -Y; Chua, C -K ^[1]; Soni, Amarjit ^[2]

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1. Institute of Physics, Academia Sinica, Taipei, Taiwan 115 (China)
2. Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)

Motivated by the recent indications of the possibility of sizable deviations of the mixing-induced CP violation parameter, S{sub f}, in the penguin-dominated b{yields}sqq transition decays such as B{sup 0}{yields}({phi},{omega},{rho}{sup 0},{eta}{sup '},{eta},{pi}{sup 0},f{sub 0})K{sub S} from sin2{beta} determined from B{yields}J/{psi}K{sub S}, we study final-state rescattering effects on their decay rates and CP violation. Recent observations of large direct CP asymmetry in modes such as B{sup 0}{yields}K{sup +}{pi}{sup -},{rho}{sup -}{pi}{sup +} suggest that final-state phases in two-body B decays may not be small. It is therefore important to examine these long-distance effects on penguin-dominated decays. Such long-distance effects on S{sub f} are found to be generally small [i.e. O(1-2%)] or negligible except for the {omega}K{sub S} and {rho}{sup 0}K{sub S} modes where S{sub f} is lowered by around 15% for the former and increased by the same percentage for the latter. However, final-state rescattering can enhance the {omega}K{sub S}, {phi}K{sub S}, {eta}{sup '}K{sub S}, {rho}{sup 0}K{sub S}, and {pi}{sup 0}K{sub S} rates significantly and flip the signs of direct CP asymmetries of the last two modes. Direct CP asymmetries in {omega}K{sub S} and {rho}{sup 0}K{sub S} channels are predicted to be A{sub {omega}}{sub K{sub S}}{approx_equal}-0.13 and A{sub {rho}{sup 0}}{sub K{sub S}}{approx_equal}0.47, respectively. However, direct CP asymmetry in all the other b{yields}s penguin-dominated modes that we study is found to be rather small ( < or approx. a few percent), rendering these modes a viable place to search for the CP-odd phases beyond the standard model. Since {delta}S{sub f} ({identical_to}-{eta}{sub f}S{sub f}-S{sub J/{psi}}{sub K{sub S}}, with {eta}{sub f} being the CP eigenvalue of the final state f) and A{sub f} are closely related, the theoretical uncertainties in the mixing-induced parameter S{sub f} and the direct CP asymmetry parameter A{sub f} are also coupled. Based on this work, it seems difficult to accommodate |{delta}S{sub f}|>0.10 within the standard model for B{sup 0}{yields}({phi},{omega},{rho}{sup 0},{eta}{sup '},{eta},{pi}{sup 0})K{sub S}; in particular, {eta}{sup '}K{sub S} is especially clean in our picture. For f{sub 0}K{sub S}, at present we cannot make reliable estimates. The sign of the central value of {delta}S{sub f} for all the modes we study is positive but quite small, compared to the theoretical uncertainties, so that at present conclusive statements on the sign are difficult to make.

• OSTI ID: 20711048
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 1 Vol. 72; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
B NEUTRAL MESONS
CP INVARIANCE
DISTANCE
EIGENFUNCTIONS
EIGENVALUES
ETA MESONS
ETA PRIME-958 MESONS
FINAL-STATE INTERACTIONS
HADRONIC PARTICLE DECAY
J PSI-3097 MESONS
KAONS NEUTRAL SHORT-LIVED
OMEGA-782 MESONS
PIONS MINUS
PIONS NEUTRAL
PIONS PLUS
QUARKS
RESCATTERING
RHO-770 MESONS
STANDARD MODEL
TWO-BODY PROBLEM