A 'known' CP asymmetry in tau decays

作者：Bigi II^*; Sanda AI

来源：Physics Letters B, 2005, 625(1-2): 47-52.

DOI：10.1016/j.physletb.2005.08.033

We point out that dynamics known from the observed CP violation in K-L -> pi(-/+)l +/- v coupled with CPT invariance generate a CP asymmetry of 3.3 x 10(-3) in tau(+/-) -> vKS pi(+/-) -> v[pi(+) pi(-)](K)(pi +/-). The equality of the tau(+) and tau(-) lifetimes required by CPT symmetry is restored in an intriguing way as the combined effect of long-lived K -> pi(+) pi(-) as well as contributions from K-L-K-S interference. While little new can be learnt from this CP asymmetry, the latter has to be accounted for, since CP asymmetries in T -> vK pi channels are prime candidates for revealing the intervention of New Physics. This 'known' CP asymmetry provides a very useful calibration point in such searches. It also provides a test of CPT symmetry (as well as the Delta Q = Delta S selection rule).

• 出版日期2005-10-6