Search for Violation of $CPT$ and Lorentz invariance in ${B_s^0}$ meson oscillations

TL;DR

This study searches for violations of CPT and Lorentz invariance in ${B_s^0}$ meson oscillations using Fermilab data, finding no evidence but setting new limits on possible violations.

Contribution

First experimental search for CPT violation in ${B_s^0}$ meson mixing, providing constraints on Lorentz-invariance violating coefficients.

Findings

No evidence for CPT violation was observed.

Set 95% confidence limits on CPT-violating parameters.

Provided the first experimental bounds on flavor-dependent CPT and Lorentz violation.

Abstract

We present the first search for CPT-violating effects in the mixing of ${B_s^0}$ mesons using the full Run II data set with an integrated luminosity of 10.4 fb$^{-1}$ of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. We measure the CPT-violating asymmetry in the decay $B_s^0 \to \mu^\pm D_s^\pm$ as a function of celestial direction and sidereal phase. We find no evidence for CPT-violating effects and place limits on the direction and magnitude of flavor-dependent CPT- and Lorentz-invariance violating coupling coefficients. We find 95\% confidence intervals of $\Delta a_{\perp} < 1.2 \times 10^{-12}$ GeV and $(-0.8 < \Delta a_T - 0.396 \Delta a_Z < 3.9) \times 10^{-13}$ GeV.