Recent Results in Heavy Hadron Spectroscopy

Abstract

The ARGUS Collaboration observes the decay of the ∑ _c to Λ ⁺ _c Π ^± and reports the mean ∑ _c Λ ⁺ _c mass difference and the ∑ _c isospin mass splitting, decay rate to Λ _c , and Peterson ? parameter. The E-691 group observes the signal ∑ ⁰ _c → Λ ⁺ _c π^- and reports the ∑ _c Λ ⁺ _c mass difference and the photoproduction cross section ratio of ∑ _c relative to Λ _c at 145 GeV. E-691 observes a D ^**0(2459) which decays to Dπ and confirms the existence of the D ^**0(2420). ARGUS confirms the D ^**0(2459). After studying the production rate, Doppler broadening, and average energies of the photons emitted during B* and B ^* _s decays, the CUSB Collaboration reports that B _s mesons are produced on the ?(5S) resonance.