Mass spectra and radiative transitions of doubly heavy baryons in a relativized quark model

Abstract

We study the mass spectra and radiative decays of doubly heavy baryons within the diquark picture in a relativized quark model. The mass of the $J^P=1/2^{+}$ ${\Xi }_{cc}$ ground state is predicted to be 3606 MeV, which is consistent with the mass of ${\Xi }_{cc}^{++}(3621)$ newly observed by the LHCb collaboration. The predicted mass gap between two $S$ wave states, ${\Xi }_{cc}^{\ast }$ ($J^P=3/2^{+}$) and ${\Xi }_{cc}$ ($J^P=1/2^{+}$), is 69 MeV. Furthermore, the radiative transitions of doubly heavy baryons are also estimated by using the realistic wave functions obtained from relativized quark model. The radiative decay widths of ${\Xi }_{cc}^{\ast ++}\to {\Xi }_{cc}^{++}\gamma$ and ${\Xi }_{cc}^{\ast +}\to {\Xi }_{cc}^{+}\gamma$ are predicted to be about 7 and 4 keV, respectively. These predictions of doubly heavy baryons can provide helpful information for future experimental searches.

Comments: 8 pages, 2 figure. The size effects of the diquarks are considered. Version accepted by Phys. Rev. D