Radiative decays of $1^{++}$ heavy mesons in the covariant light-front   approach
  We calculate the predicted width for the radiative decay of a $1^{++}$ heavy meson via the channel $1^{++} \to 1^{--} +\gamma$ in the covariant light-front quark model. Specifically, we compute the decay widths for $\chi_{c1}(1P) \to J/\psi + \gamma$ and $\chi_{b1}(nP) \to \Upsilon(n'S) + \gamma$. The results are compared with experimental data and with predictions from calculations based on nonrelativistic models and their extensions to include relativistic effects. 
Yan-Liang Shi
hep-ph