First Observation of Doubly Charmed Baryons

Abstract

The SELEX experiment (E781) at Fermilab has observed two statistically compelling high mass states near 3.6 GeV/c^2, decaying to Lambda_c+ K- pi+ and Lambda_c+ K- pi+ pi+. These final states are Cabibbo-allowed decay modes of doubly charmed baryons ${\Xi }_{cc}^{+}$ and ${\Xi }_{cc}^{++}$, respectively. The masses are in the range expected from theoretical considerations, but the spectroscopy is surprising. SELEX also has weaker preliminary evidence for a state near 3.8 GeV/${\mathrm{c}}^2$, a high mass state decaying to Lambda_c+ K- pi+ pi+, possibly an excited ${\Xi }_{cc}^{++}$ (ccu*). Data are presented and discussed.

Contribution to Advanced Study Institute, "Symmetries and Spin" - Praha-SPIN-2002, Workshop Chairman, M. Finger, http://mfinger.home.cern.ch/mfinger/praha2002/

Cited by in corpus (1)

• Heavy Hadron Spectroscopy