Higher order corrections to spin-isospin quantities in the chiral bag model

We calculate higher order contributions to spin-isospin quantities such as isovector axial vector coupling constant gA and the isovector magnetic moment μl=1 in the chiral bag model. Quark contributions to those quantities are fully evaluated including vacuum polarization effects up to the order of Ω1 in the cranking method for spin and isospin projection. It is confirmed that the higher order corrections have a sizable effect on gA at reasonable bag radii. The chiral bag model now has the correct limits of the MIT bag model at R → ∞ and the Skyrme model at R → 0.