The isotensor pentaquark

Further consequences of the 1540 MeV Θ+ resonance as an isotensor pentaquark beyond Capstick et al. are explored. It is argued that the SAPHIR data may not currently exclude the existence of the charged partner Θ++. The usual prediction of the dominance of non-resonant Θ+K, and Θ+ K*, final states in photoproduction on the proton is argued not to obtain for an isotensor Θ+. This enhances the importance of excited baryon final states, where the excited baryon decays to Θ+K or Θ+ K*; as well as the non-resonant Θ+Kπ final state. The small width of the recently discovered Ξ - cascade resonance to Ξ-π - is easier to explain if Θ+ is an isotensor pentaquark than if it is in the 10-bar representation, due to both an isospin and U-spin selection rule. A new production diagram for Θ+ in the photoproduction on the deuteron is suggested