# TAM2013 - Venice

4-8 March 2013
Venice
Europe/Rome timezone

## Direct observation of time-reversal violation in B0 decays

5 Mar 2013, 10:20
1h
Venice

#### Venice

<a href="https://maps.google.com/?ll=45.427428,12.365663&spn=0.001304,0.001635&t=w&z=20">Campo della Chiesa 3, Sant'Elena</a>
Invited

### Speaker

Dr Giuseppe Finocchiaro (INFN Laborotorio Nazionale di Frascati)

### Description

The B factories have established with great accuracy the violation of the CP symmetry in the B system. However, no direct observation of time-reversal violation had been performed prior to the work, recently published by the BABAR Collaboration, discussed in the present talk. The quantum entanglement of B-Bbar pairs produced in the decay of the Y(4S) resonance at the PEP-II asymmetric B Factory is exploited to perform an unambiguous t-transformation (inversion of the sign of t and exchange of the in'' and out'' states). The comparison of the decay rates of reference and t-transformed states as a function of the decay time difference allows us to establish for the first time T violation in the B system with a significance of 14 sigma, independently from assumptions on the CPT symmetry.

### Primary author

Dr Giuseppe Finocchiaro (INFN Laborotorio Nazionale di Frascati)

 Slides