Center of mass motion in bag model

Despite its success with mass spectra, the reputation of the bag model has been marred by embarrassment of the center of mass motion. It leads to severe theoretical inconsistencies. For instance, the masses and the decay constants would no longer be independent of the momentum. In this work, we provide a systematic approach to resolving this problem. Our framework can consistently compute the meson decay constants and baryon transition form factors. Notably, the form factors in the neutron β decays do not depend on any free parameters and are determined to be F1V= 1and F1A= 1.31or F1A/F1V= 1.31, which is close to the experimental value of F1A/F1V= 1.27. In addition, we find that B(Λb→ Λγ) =(6.8 ± 3.3) × 10-6, which agrees to the experimental value of(7.1 ± 1.7) × 10-6.