Subtleties in the BABAR measurement of time-reversal violation

Abstract

A first measurement of time-reversal (T) asymmetries that are not also CP asymmetries has been recently achieved by the BABAR collaboration. In this talk, which follows the work done in Ref. [1], I discuss the subtleties of this measurement in the presence of direct CP violation, CPT violation, wrong strangeness decays and wrong sign semi-leptonic decays. In particular, I explain why, in order to identify the measured asymmetries with time-reversal violation, one needs to assume (i) the absence of wrong strangeness decays or of CPT violation in strangeness changing decays, and (ii) the absence of wrong sign decays.