Are operators describing b -> s gamma?

作者：Dong Fan-Long^*; Wang Wen-Yu; Xiong Zhao-Hua

来源：Chinese Physics C, 2011, 35(1): 6-10.

DOI：10.1088/1674-1137/35/1/002

• off-shell quarks effect
• new Feynman diagrams
• Ward identity

The operators of b -> s gamma, b -> sl(+)l(-) are usually regarded as being sufficient to describe b -> s gamma gamma, b -> sl(+)l(-)gamma with the statement that contributions from diagrams without an effective vertex b -> s gamma to processes b -> s gamma gamma and b -> sl(+)l(-)gamma are negligible. In this work we present a comprehensive analysis of the transition b -> s gamma gamma and find that 1) Effects due to off-shell quarks in vertex b -> s gamma on b -> s gamma gamma are large; 2) Contributions from diagrams without an effective vertex b -> s gamma to b -> s gamma gamma are not negligible compared with others; 3) These effects cancel each other out exactly, so the operators of b -> s gamma can safely be used to describe b -> s gamma gamma.

• 出版日期2011-1
• 单位北京工业大学