Observation of a new Pentaquark Candidate State Ξ_3/2^{- -} in pp Collisions with the NA49 Detector

by Dr. K. Kadija (Rudjer Boskovic Institute, Zagreb, Croatia)

Tuesday 25 Nov 2003, 16:30 → 17:30 Europe/Zurich

503/1-001 - Council Chamber (CERN)

Results of resonance searches in the Ξ ^- π ^-, Ξ ^- π ⁺, Ξbar ⁺ π ^- and Ξbar ⁺ π ⁺ invariant mass spectra in pp collisions at √s = 17.2 GeV will be presented. A narrow resonance with mass of 1.862 +/- 0.002 GeV/c² and width below the detector resolution of ~ 0.018 GeV/c² is observed. This state is identified as a candidate for the exotic Ξ_3/2 ^{- -} pentaquark baryon with a quark content of (ds ds ubar). At the same mass an indication of a peak is observed in the Ξ ^- π ⁺, Ξbar ⁺ π ^- and Ξbar ⁺ π ⁺ invariant mass spectra. Also, preliminary results of resonance searches in other possible decay chains of the predicted pentaquark states will be presented.

Organiser(s): Rolf Landua / EP Division

Note: Tea & coffee will be served at 16:00 hrs.