弱衰变B_d→J/ψK_S 中的CP破坏与新物理(英文)

Possible Implications of Small or Large CP Violation in B_d^0 vs _d^0→J/ψK_S Decays

最近BaBar与Belle国际合作组对弱衰变Bd→J ψKS 中的CP破坏测量结果似乎暗示有新物理存在于B0d B0d 混合 .为此给出一个模型无关的分析 ,以说明新物理对标准模型结果的可能修正 .特别强调 ,即使实验证明Bd→J ψKS 中的CP破坏效应与标准模型的预言相符 ,仍然有可能存在新物理 .

We argue that a small or large CP-violating asymmetry A ψK S in B 0 d vs 0 d→J/ψK S decays,which seems to be favored by the recent BaBar or Belle data,might hint at the existence of new physics in B 0 d- 0 d mixing. We present a model-independent framework to show how new physics modifies the standard-model CP-violating asymmetry A SM ψK S. We particularly emphasize that an experimental confirmation of A ψK S≈A SM ψK S must not imply the absence of new physics in B 0 d- 0 d mixing.