HADRON SPECTROSCOPY AT CLAS

Meson photoproduction was studied at the CEBAF Large Acceptance Spectrometer (CLAS) utilizing a 5.5 GeV/c photon beam incident on a hydrogen target. Here we report on the partial wave analyzes (PWA) performed on the exclusive final states π+π+π-n and K+K-π+n. In addition, CLAS has data on the final state π+π0π-p which will be reported in the near future. The analysis of the π+π+π- system shows clearly the a2(1320), as well as evidence for the a1(1260) and the π2(1670). The π1(1600), previously observed in π-p interactions, is seen very weakly here. In the K+K-π+n channel there is is evidence for the Θ+(1540) S=+1 baryon pentaquark. The PWA of this system gives an excellent description of the background which rules out mesonic reflection as a source of the signal.