Precision Measurement of $D_{s}^{*+} - D_{s}^{+}$ Mass Difference with $D_{s}^{*+} \to D_{s}^{+}(\to K^{+} K^{-} \pi^{+})\pi^{0}$

TL;DR

This paper reports a highly precise measurement of the mass difference between $D_{s}^{*+}$ and $D_{s}^{+}$ mesons using $e^+e^-$ collision data, significantly improving the accuracy over previous results.

Contribution

The study provides the most precise measurement to date of the $D_{s}^{*+} - D_{s}^{+}$ mass difference, utilizing a specific decay channel and data from the BESIII detector.

Findings

Measured $ riangle m_s = 144201.9$ keV/$c^2$ with improved precision.

Achieved a sevenfold increase in measurement accuracy compared to previous averages.

Quantified uncertainties from statistical, systematic, and PDG sources.

Abstract

We measure the mass difference between $D_{s}^{*+}$ and $D_{s}^{+}$, $\Delta m_s$, using the decay chain $D_{s}^{*+} \to D_{s}^{+}(\to K^{+} K^{-} \pi^{+})\pi^{0}$, utilizing $e^+e^-$ annihilation data corresponding to an integrated luminosity of 3.19 fb$^{-1}$ collected at a center-of-mass energy of 4.178 GeV with the BESIII detector. The measured value of $\Delta m_s = [144\,201.9 \pm 44.2({\rm stat.}) \pm 29.9({\rm syst.}) \pm 15.0({\rm PDG})]$ keV/$c^2$ is about seven times more precise than the current Particle Data Group average, where the last uncertainty is from the Particle Data Group average of the $D^{*+} - D^{+}$ mass difference.