Results on Charm Baryon Spectroscopy from Tevatron

TL;DR

This paper reports precise measurements of the masses and decay widths of various charm baryon states, including Lambda_c and Sigma_c excitations, using high-resolution data from the CDF experiment at the Tevatron.

Contribution

It provides the first detailed spectroscopic measurements of certain charm baryon excitations with significantly higher statistics than previous studies.

Findings

Measured mass differences of Lambda_c and Sigma_c states.

Determined decay widths of the excited charm baryons.

Achieved higher precision in spectroscopic properties than prior experiments.

Abstract

Due to an excellent mass resolution and a large amount of available data, the CDF experiment, located at the Tevatron proton-antiproton accelerator, allows the precise measurement of spectroscopic properties, like mass and decay width, of a variety of states. This was exploited to examine the first orbital excitations of the Lambda_c baryon, the resonances Lambda_c(2595) and Lambda_c(2625), in the decay channel Lambda_c^+ pi^+ pi^-, as well as the Lambda_c spin excitations Sigma_c(2455) and Sigma_c(2520) in its decays to Lambda_c^+ pi^- and Lambda_c^+ pi^+ final states in a data sample corresponding to an integrated luminosity of 5.2 invfb. We present measurements of the mass differences with respect to the Lambda_c and the decay widths of these states, using significantly higher statistics than previous experiments.