Eur. Phys. J. A (2007) 32: 183-199
https://doi.org/10.1140/epja/i2007-10364-y

Regular Article - Hadron Physics

Static properties and semileptonic decays of doubly heavy baryons in a nonrelativistic quark model

¹ Departamento de Fısica Atómica, Molecular y Nuclear, Universidad de Granada, E-18071, Granada, Spain
² Departamento de Fısica Fundamental e IUFFyM, Facultad de Ciencias, Grupo de Fısica Nuclear, E-37008, Salamanca, Spain

Received: 15 March 2007
Accepted: 13 April 2007
Published online: 8 May 2007

Abstract

We evaluate static properties and semileptonic decays for the ground state of doubly heavy Ξ, Ξ', Ξ ^* and Ω, Ω', Ω ^* baryons. Working in the framework of a nonrelativistic quark model, we solve the three-body problem by means of a variational ansatz made possible by heavy-quark spin symmetry constraints. To check the dependence of our results on the inter-quark interaction we use five different quark-quark potentials that include a confining term plus Coulomb and hyperfine terms coming from one-gluon exchange. Our results for static properties (masses, charge radii and magnetic moments) are, with a few exceptions for the magnetic moments, in good agreement with a previous Faddeev calculation. Our much simpler wave functions are used to evaluate semileptonic decays of doubly heavy Ξ, Ξ'(J = 1/2) and Ω, Ω'(J = 1/2) baryons. Our results for the decay widths are in good agreement with calculations done within a relativistic quark model in the quark-diquark approximation.