Analysis ofΛb→Λcweak decays in heavy quark effective theory

The ${\Lambda }_b\to {\Lambda }_c$ semileptonic decay is analyzed in the framework of heavy quark effective theory to the order of ${1/m}_c$ and ${1/m}_b.$ The QCD sum rule and large $N_c$ predictions to the decay form factors are applied. We argue that the subleading baryonic Isgur-Wise function in the large $N_c$ limit vanishes. The decay rates, distributions, and asymmetry parameters are calculated numerically. Some of the nonleptonic decay modes are discussed in the end.