B{yields}K{sub 1}{gamma} decays in the light-cone QCD sum rules

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

DOI:https://doi.org/10.1103/PHYSREVD.77.094023· OSTI ID:21250129

Hatanaka, Hisaki; Yang, K -C ^[1]

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1. Department of Physics, Chung Yuan Christian University, Chung-Li 320, Taiwan (China)

We present a detailed study of B{yields}K{sub 1}(1270){gamma} and B{yields}K{sub 1}(1400){gamma} decays. Using the light-cone sum rule technique, we calculate the B{yields}K{sub 1A}(1{sup 3}P{sub 1}) and B{yields}K{sub 1B}(1{sup 1}P{sub 1}) tensor form factors, T{sub 1}{sup K{sub 1A}}(0) and T{sub 1}{sup K{sub 1B}}(0), where the contributions are included up to the first order in m{sub K{sub 1}}/m{sub b}. We resolve the sign ambiguity of the K{sub 1}(1270)-K{sub 1}(1400) mixing angle {theta}{sub K{sub 1}} by defining the signs of decay constants, f{sub K{sub 1A}} and f{sub K{sub 1B}}{sup perpendicular}. From the comparison of the theoretical calculation and the data for decays B{yields}K{sub 1}{gamma} and {tau}{sup -}{yields}K{sub 1}{sup -}(1270){nu}{sub {tau}}, we find that {theta}{sub K{sub 1}}=-(34{+-}13) deg. is favored. In contrast to B{yields}K*{gamma}, the hard-spectator contribution suppresses the B{yields}K{sub 1}(1270){gamma} and B{yields}K{sub 1}(1400){gamma} branching ratios slightly. The predicted branching ratios are in agreement with the Belle measurement within the errors. We point out that a more precise measurement for the ratio R{sub K{sub 1}}=B(B{yields}K{sub 1}(1400){gamma})/B(B{yields}K{sub 1}(1270){gamma}) can offer a better determination for the {theta}{sub K{sub 1}}, and consequently the theoretical uncertainties can be reduced.

• OSTI ID: 21250129
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 9 Vol. 77; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
BRANCHING RATIO
COMPARATIVE EVALUATIONS
FORM FACTORS
GAMMA DECAY
K1-1270 MESONS
K1-1400 MESONS
LIGHT CONE
QUANTUM CHROMODYNAMICS
SUM RULES
TAU NEUTRINOS
WEINBERG ANGLE