Doubly heavy Baryons from QCD Spectral Sum Rules
arXiv:1009.2428 · doi:10.1016/j.nuclphysbps.2010.10.068
Abstract
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.
4 pages, 3 figures, 1 table talk given by R.M. Albuquerque at QCD 10 (28th june - 2nd july 2010, Montpellier), to appear in Nucl. Phys. B (Proc. Suppl.)