First Observation of the $\Sigma_{c}^{*+}$ Baryon and a New Measurement of the $\Sigma_{c}^{+}$ Mass

TL;DR

This paper reports the first observation of the $oldsymbol{ ext{Sigma}_c^{*+}}$ baryon and provides a new measurement of the $oldsymbol{ ext{Sigma}_c^{+}}$ mass using data from the CLEO detector, advancing understanding of charmed baryons.

Contribution

The study presents the first detection of the $ ext{Sigma}_c^{*+}$ baryon and refines the mass measurement of the $ ext{Sigma}_c^{+}$ baryon, providing important data for baryon spectroscopy.

Findings

First observation of $ ext{Sigma}_c^{*+}$ baryon.

Measured mass difference $M( ext{Sigma}_c^{*+}) - M( ext{Lambda}_c^+)$ = 231.0 ± 1.1 ± 2.0 MeV.

Updated mass difference $M( ext{Sigma}_c^{+}) - M( ext{Lambda}_c^+)$ = 166.4 ± 0.2 ± 0.3 MeV.

Abstract

Using data recorded with the CLEO II and CLEO II.V detector configurations at the Cornell Electron Storage Rings, we report the first observation and mass measurement of the $\Sigma_c^{*+}$ charmed baryon, and an updated measurement of the mass of the $\Sigma_c^+$ baryon. We find $M(\Sigma_c^{*+})-M(\Lambda_c^+)$= 231.0 +- 1.1 +- 2.0 MeV, and $M(\Sigma_c^{+})-M(\Lambda_c^+)$= 166.4 +- 0.2 +- 0.3 MeV, where the errors are statistical and systematic respectively.