Determining Pentaquark Quantum Numbers from Strong Decays

Abstract

Assuming that the recently observed ${\Theta }^{+}$ and ${\Xi }^{--}$ are members of an anti-decuplet of SU(3), decays to ground state baryons and mesons are calculated using an effective Lagrangian which incorporates chiral and SU(3) symmetry. We consider the possible quantum number assignments $J^{\Pi }={1/2}^{\pm },{3/2}^{\pm }$ and calculate ratios of partial widths. The branching ratios of exotic cascades can be used to discriminate between even and odd parity pentaquarks.

Comments: 9 pages, references added, accepted for publication in PLB