Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B0 or B¯0), and J/ψKL0 or cc¯KS0 final states (referred to as B+ or B-), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, B¯0→B- and B-→B¯0, as a function of the time difference between the two B decays. Using 468×106 BB¯ pairs produced in Υ(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding ΔST+=-1.37±0.14(stat)±0.06(syst) and ΔST-=1.17±0.18(stat)±0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation.
Titolo: | Observation of Time-Reversal Violation in the B^{0} Meson System |
Autori: | |
Data di pubblicazione: | 2012 |
Rivista: | |
Abstract: | Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B0 or B¯0), and J/ψKL0 or cc¯KS0 final states (referred to as B+ or B-), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, B¯0→B- and B-→B¯0, as a function of the time difference between the two B decays. Using 468×106 BB¯ pairs produced in Υ(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding ΔST+=-1.37±0.14(stat)±0.06(syst) and ΔST-=1.17±0.18(stat)±0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation. |
Handle: | http://hdl.handle.net/11368/2767934 |
Digital Object Identifier (DOI): | http://dx.doi.org/10.1103/PhysRevLett.109.211801 |
Appare nelle tipologie: | 1.1 Articolo in Rivista |
File in questo prodotto:
File | Descrizione | Tipologia | Licenza | |
---|---|---|---|---|
PhysRevLett.109.211801-accepted.pdf | Documento in Pre-print | Digital Rights Management non definito | Administrator Richiedi una copia |