  We consider the ratios of doubly heavy baryon masses using Double Ratios of
Sum Rules (DRSR), which are more accurate than the usual simple ratios used for
getting hadron masses. Our results are comparable with the ones from potential
models. The Xi^*_{QQ}-Xi_{QQ} splittings seem to behave like 1/M_Q and can only
allow the electromagnetic decay Xi^*_{QQ} to Xi_{QQ}+gamma but not to Xi_{QQ}+
pi. Our results also show that the SU(3) mass-splittings are (almost)
independent of the spin of the baryons and behave approximately like 1/M_Q,
which could be understood from the QCD expressions of the corresponding
two-point correlator. Our results can improved by including radiative
corrections to the SU(3) breaking terms and can be tested, in the near future,
at Tevatron and LHCb.
