Time reversal symmetry violation in entangled pseudoscalar neutral charmed mesons

TL;DR

This paper investigates time reversal symmetry violation in entangled neutral D mesons, exploring potential signals and effects like CPT violation, with implications for detecting new physics in high-precision experiments.

Contribution

It provides a detailed analysis of TV signals and the $oldsymbol{ ext{omega}}$ effect in entangled D mesons, including estimates of observable asymmetries and experimental sensitivities.

Findings

TV asymmetries are of order 10^{-5} to 10^{-4} within the Standard Model.

The $oldsymbol{ ext{omega}}$ effect can modify asymmetries by 10-30% for $|oldsymbol{ ext{omega}}| ext{~}10^{-4}$.

With $10^9$ to $10^{10}$ events, TV signals and bounds on $oldsymbol{ ext{omega}}$ can be achieved.

Abstract

The direct observation of time reversal symmetry violation (TV) is important for the test of $CPT$ conservation and the Standard Model. In this paper, we study both time-dependent and time-independent genuine TV signals in entangled $D^0-\bar{D}^0$ pairs. A possible $CPT$-violation effect called the $\omega$ effect is also investigated. In the $C=-1$ entangled state, the asymmetries due to TV are calculated to be of the order of $10^{-5}$ to $10^{-4}$ within the Standard Model, but the modification due to the $\omega$ effect in the $C=-1$ states is found to be about $10\%-30\%$ when $|\omega|\sim 10^{-4}$. This result is consistent with our Monte Carlo simulation, which implies that with $10^9$ to $10^{10}$ events, TV signals can be observed in the entangled $D^0-\bar{D}^0$ pairs, and the bound of $\omega \sim 10^{-3}$ can be reached. The time-dependent and the time-independent asymmetries in the $C=-1$ $D^0-\bar{D}^0$ system provides a window to detect new physics such as the $\omega$ effect, although they are not easily observable.