Masses and magnetic moments of pentaquarks
نویسنده
چکیده
We discuss the spectroscopy of the recently discovered exotic baryons as pentaquark qq̄ configurations. The ground state pentaquark configuration depends on the interplay between spin-flavor and orbital contributions to the mass operator. A simple calculation in an algebraic model gives a ground state antidecuplet pentaquark with isospin I = 0 and negative parity. The lowest pentaquark with positive parity is an antidecuplet isosinglet Θ state at an excitation energy of 128 MeV. The corresponding magnetic moments are found to be 0.382 μN for the negative parity Θ + pentaquark, and 0.089 μN for positive parity. PACS numbers: 14.20.Jn, 12.39.Mk, 13.40.Em, 12.39.-x
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