Center of mass motion in bag model

Despite the great success on the mass spectra, the reputation of the bag model has been closely followed by the embarrassment from 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 systematical approach to resolve this problem. The meson decay constants as well as the baryon transition form factors can be computed consistently in our framework. Notably, the form factors in the neutron $β$ decays do not depend on any free parameters, and are determined to be $F^V_1 =1$ and $F^A_1 = 1.31$ or $F_1^A/F_1^V= 1.31$, which is close the experimental value of $F^A_1/F^V_1 = 1.27$. In addition, we find that ${\cal B} (Λ_b \to Λγ) = (6.8 \pm 3.3 ) \times 10^{-6}$, which agrees to the experimental value of $(7.1\pm 1.7)\times 10^{-6}$.

No reviews yet.

No comments yet.