Charmed Baryon Spectroscopy from Lattice QCD with Nf=2+1+1 flavors
Abstract
We present preliminary results of the calculation of the positive-parity ground state charm baryon spectrum using of Nf=2+1+1 dynamical quarks. The calculation uses a relativistic heavy-quark action for the valence charm quark, clover-Wilson fermions for the valence light quarks and HISQ sea quarks. The spectrum is calculated with a lightest pion mass around 220 MeV and two lattice spacings (a0.12 fm and 0.09 fm) are used to extrapolate to continuum limit. Our preliminary results are consistent with the currently measured baryon spectrum, except for the isospin-averaged J=1/2 cc which is approximately 2 σ above the SELEX observed value. We predict the yet-to-be-discovered double and triple-charm baryons cc*, cc, cc*, ccc$ to have masses 3665(42)(29) MeV, 3694(40)(45) MeV, 3739(35)(21) MeV and 4782(24)(28) MeV, respectively.