Magnetic moments and charge radii of decuplet baryons in a field-theoretic quark model.

Abstract

We make nonrelativistic as well as relativistic estimations of the magnetic moments and charge radii of decuplet baryons in a field-theoretic quark model, where translationally invariant decuplet baryon states are described by constituent quark field operators and harmonic oscillator wave functions. The relativistic estimations of the magnetic moments made are, however, O(\ensuremath{\Vert}p\ensuremath{\rightarrow}\ensuremath{\Vert}/m) corrections over the nonrelativistic contribution where the higher order corrections for the ground states treated here, being small, are neglected. The constituent quark field operators here with a particular ansatz satisfy the equal time algebra and are also Lorentz boosted in a definite manner to describe the baryons in motion. The estimations for the magnetic moments and their ratios, with a single harmonic oscillator radius parameter for the octet as well as decuplet baryons, show a reasonable agreement with the most recent experimental measurements for ${\mathrm{\ensuremath{\Delta}}}^{++}$ and ${\mathrm{\ensuremath{\Omega}}}^{\mathrm{\ensuremath{-}}}$, which have constrained different models of hadrons to explain both. We feel that the final results in this regard, expected in the near future in succeeding experiments, can further constrain different theoretical models. However, because of the lack of experimental data, the estimated charge radii in the present model stand as model predictions which may be verified in future experiments.