Constraints on light dark sector particles from lifetime difference of heavy neutral mesons

TL;DR

This paper explores how light dark matter particles could influence heavy neutral meson mixing, providing new constraints on dark sector interactions through lifetime difference measurements.

Contribution

It introduces a novel approach to constrain dark matter interactions by analyzing their effects on meson lifetime differences, complementing existing decay-based methods.

Findings

Lifetime differences constrain dark matter interactions more tightly.

Effective operators impact charm and beauty meson mixing.

New bounds complement decay-based dark matter searches.

Abstract

Heavy meson decays with missing energy in the final state offer interesting avenues to search for light invisible new physics such as dark matter (DM). In this context, we show that such new physics (NP) interactions also affect lifetime difference in neutral meson-antimeson mixing. We consider general dimension-six effective quark interactions involving a pair of DM particles and calculate their contributions to lifetime difference in beauty and charm meson systems. We use the latest data on mixing observables to constrain the relevant effective operators. We find that lifetime differences provide novel and complementary flavor constraints compared to those obtained from heavy meson decays.