Observation of New States Decaying into $\Lambda_{c}^{+}\pi^{-}\pi^{+}$

TL;DR

This paper reports the discovery of two new charmed baryon states decaying into Lambda_c^+ pi^- pi^+ using data from the CLEO detector, expanding the understanding of charmed baryon spectrum.

Contribution

First observation of two new charmed baryon states decaying into Lambda_c^+ pi^- pi^+ with measured mass differences.

Findings

Evidence for a broad state ~480 MeV above Lambda_c^+

Evidence for a narrow state 596 MeV above Lambda_c^+

Results are preliminary and based on 13.7 fb^{-1} of data.

Abstract

Using 13.7 fb^{-1} of data recorded by the CLEO detector at CESR, we investigate the spectrum of charmed baryons which decay into Lambda_c^+ pi^- pi^+ and are more massive than the Lambda_{c1} baryons. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda_c^+; the other is narrow with an invariant mass of 596 +- 1 +- 2 MeV above the Lambda_c^+ mass. These results are preliminary.