First Observation of the Sigma_c^{*+} Charmed Baryon, and New Measurements of the Sigma_c^0, Sigma_c^+, Sigma_c^{++}, and Omega_c^0 Charmed Baryons

TL;DR

This paper reports the first observation of the Sigma_c^{*+} charmed baryon, along with precise measurements of several other charmed baryons' masses and widths, based on extensive e+e- collision data.

Contribution

It provides the first measurements of the Sigma_c^{*+} baryon and the Omega_c^0 baryon, along with the most precise mass and width measurements of Sigma_c^0, Sigma_c^+, and Sigma_c^{++} baryons.

Findings

First observation of Sigma_c^{*+} baryon.

First measurement of Omega_c^0 baryon mass.

Precise measurements of Sigma_c^0, Sigma_c^+, and Sigma_c^{++} masses and widths.

Abstract

Using ~13.7 fb^{-1} of e^+e^- collision data recorded at near the Upsilon(4S) resonance by the CLEO II and CLEO II.V detector configurations on the Cornell Electron Storage Ring, we present the world's most precise measurements of the Sigma_c^0, Sigma_c^+, and Sigma_c^{++} charmed-baryon masses as well as the first measurements of the intrinsic widths of the Sigma_c^0 and Sigma_c^{++} baryons. We also report on the first observation and mass measurement of the Sigma_c^{*+} charmed baryon, M(Sigma_c^{*+}) - M(Lambda_c^+) = (231.0 +- 1.1[stat] +- 2.0[syst]) MeV/c^2, and the first CLEO observation of the Omega_c^0 baryon, for which we measure a mass M(Omega_c^0) = (2694.6 +- 2.6[stat] +- 1.9[syst]) MeV/c^2 from a sample of (40.4 +- 9.0[stat]) candidate events. All new results are preliminary.