Choice of heavy baryon currents in QCD sum rules

In this paper we investigate the effects due to the mixing of two interpolating currents for ground-state baryons within the framework of heavy quark effective theory using the QCD sum rule approach. Both two-point and three-point sum rules, and thus the mass, coupling constant, and Isgur-Wise function sum rules are considered. It is interesting to contrast those results with each other. Based on the Isgur-Wise functions obtained in this paper, we also analyze the effects of current mixing to Lambda type and and Sigma type semileptonic decays Lambda(b)-->Lambda(c)l (nu) over bar, Sigma(b)-->Sigma(c)l (nu) over bar, and Sigma(b)-->Sigma(c)(*)l (nu) over bar. Decay widths corresponding to various mixing parameters are obtained and can be compared to the experimental data.