A Precision Measurement of the Lambda_c Baryon Mass

TL;DR

This paper reports a highly precise measurement of the Lambda_c^+ baryon mass using specific decay channels in data collected by the BaBar detector, achieving a measurement with minimal uncertainty.

Contribution

The study provides the most precise Lambda_c^+ mass measurement to date, utilizing novel decay reconstruction and detailed systematic uncertainty analysis.

Findings

Lambda_c^+ mass measured as 2286.46 ± 0.14 MeV/c^2

Systematic uncertainties dominated by tracking material and magnetic field

Measurement improves the precision of baryon mass values

Abstract

The $\Lambda_c^+$ baryon mass is measured using $\Lambda_c^+\to\Lambda K^0_S K^+$ and $\Lambda_c^+\to\Sigma^0 K^0_S K^+$ decays reconstructed in 232 fb$^{-1}$ of data collected with the BaBar detector at the PEP-II asymmetric-energy $e^+e^-$ storage ring. The $\Lambda_c^+$ mass is measured to be $2286.46\pm0.14\mathrm{MeV}/c^2$. The dominant systematic uncertainties arise from the amount of material in the tracking volume and from the magnetic field strength.