Theoretical corrections of RD and RD*

R-D(*) is the ratio of branching ratio (B) over bar -> D-(*) tau(nu) over bar (tau) to (B) over bar -> D((*))l (nu) over bar (l) (l = e, mu). There is a gap of 2 sigma(exp) or more between its experimental value and the prediction under the standard model (SM). People extend the MSSM with the local gauge group U(1)(X) to obtain the U(1)(X)SSM. Compared with MSSM, U(1)(X)SSM has more superfields and effects. In U(1)(X)SSM, we research the semileptonic decays (B) over bar -> D((*))l (nu) over bar (l) and calculate R-D(*). The numerical results of R-D(*) are further corrected under U(1)(X)SSM, which are much better than the SM predictions. After correction, the theoretical value of R-D(*) can reach one sigma(exp) range of the averaged experiment central value.

Automated summary

This study investigates the ratio of semileptonic decays and corrects the experimental values using U(1)(X)SSM, resulting in theoretical values that are closer to the experimental values.