# Precise measurements of $D$ meson lifetimes

## TL;DR

This paper presents the most precise measurements to date of $D^0$ and $D^+$ meson lifetimes using data from the Belle II experiment, confirming previous results with improved accuracy.

## Contribution

First precise measurements of $D^0$ and $D^+$ lifetimes using Belle II data, enhancing the accuracy of charm meson lifetime data.

## Key findings

- $D^0$ lifetime measured as 410.5 fs with 1.1 fs statistical uncertainty
- $D^+$ lifetime measured as 1030.4 fs with 4.7 fs statistical uncertainty
- Results are consistent with previous measurements and are the most precise to date.

## Abstract

We report the result of $D^0$ and $D^+$ lifetime measurement using $D^0\to K^-\pi^+$ and $D^+\to K^-\pi^+\pi^+$ decays reconstructed using $72~{\rm fb^{-1}}$ of data collected by the Belle II experiment at SuperKEKB asymmetric-energy $e^{+}e^{-}$ collider. The results, $\tau(D^0)=410.5\pm1.1({\rm stat})\pm0.8({\rm syst})~{\rm fs}$ and $\tau(D^+)=1030.4\pm4.7({\rm stat})\pm 3.1({\rm syst})~{\rm fs}$, are the most precise to date and are consistent with previous measurements.