Measurement of masses of the Ξ c (2645) and Ξ c (2815) baryons and observation of Ξ c (2980) → Ξ c (2645) π
Journal
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Journal Volume
665
Journal Issue
1
Pages
9-15
Date Issued
2008
Author(s)
Lesiak, T. et al.(Belle Collaboration)
Abstract
We report a precise measurement of the masses of the Ξc (2645) and Ξc (2815) baryons using a data sample of 414 fb-1 collected by the Belle Collaboration at the KEKB e+ e- collider. The states Ξc (2645)0, + are observed in the Ξc+, 0 π-, + decay modes, while the Ξc (2815)0, + are reconstructed in the Ξc (2645)+, 0 π-, + decay modes. The following mass splittings are determined: mΞc (2645)+ - mΞc (2645)0 = (- 0.1 ± 0.3 (stat) ± 0.6 (syst)) MeV / c2 and mΞc (2815)+ - mΞc (2815)0 = (- 3.4 ± 1.9 (stat) ± 0.9 (syst)) MeV / c2 with a much better precision than the current world averages. We also observe a new decay mode, Ξc (2980)0, + → Ξc (2645)+, 0 π-, +. © 2008 Elsevier B.V. All rights reserved.
Type
journal article