Light-Front Approach for Pentaquark Strong Decays

Assuming the two diquark structure for the pentaquark state as advocated in the Jaffe-Wilczek model, we study the strong decays of light and heavy parity-even pentaquark states using the light-front quark model in conjunction with the spectator approximation. The narrowness of the Θ+ width is ascribed to the p-wave configuration of the diquark pair. Taking the Θ+ width as a benchmark, we estimate the rates of the strong decays Ξ−− 3/2 → Ξ−π−,Σ−K−, Σ5c → D− s p, D ∗− s0 p and Ξ5c → D− s Σ+,D∗− s0 Σ+ with Σ5c,Ξ5c being antisextet charmed pentaquarks and D∗ s0 a scalar strange charmed meson. The ratio of Γ(Pc → BD∗ s0)/Γ(Pc → BDs) is very useful for verifying the parity of the antisextet charmed pentaquark Pc. It is expected to be of order unity for an even parity Pc and much less than one for an odd parity pentaquark.