Analyzing QCD Sum Rules for Heavy Baryons at Next-to-Leading Order in α_S

Abstract

In this talk I consider QCD sum rules for the ground state heavy baryons to leading order in $1/m_Q$ and at next-to-leading order in $α_S$ within the context of Heavy Quark Symmetry. The analysis is done at a fixed scale $μ=1 GeV$. The evolution behaviour of the residues is determined by the two-loop anomalous dimension of the heavy baryon currents calculated earlier. I compare the diagonal, non-diagonal and constituent type QCD sum rules and show that the diagonal sum rules are the most reliable one. As central values for the bound state energies I find $m(Λ_Q)-m_Q=760 MeV$ and $m(Σ_Q)-m_Q=940 MeV$. The central values for the residues are given by $F(Λ_Q)=0.030 GeV^3$ and $F(Σ_Q)=0.038 GeV^3$.