Role of the recoil and centre-of-mass corrections to the static approximation in the bag model

The internal consistency of various methods of improving the static spherical cavity approximation to the MIT Bag Model is investigated by studying electromagnetic current matrix elements between boosted bag and the boosted hadron states. In the case when the bag state is identified with the hadron bound in an external potential the consistency requirement fixes parameters of this potential allowing to calculate the improved values of the electromagnetic properties of nucleons. 17 refs., 2 tabs. (author)