Probingb-quark charged-current chiral structure viaΛ _b semileptonic decay

Abstract

Λ _b semileptonic decay to$\Lambda _c e\bar v_e$ is studied within the heavy quark effective theory, whereΛ _b is moving and polarized along the direction of its motion. Normalized energy distributions ofe andΛ _c are both calculated forV±A interactions by taking the

corrections and electronp _t cut effects into account. It is shown that the form factor (Isgur-Wise function) effects are significant: The shapes of the distribution curves are thereby considerably changed in comparison with those calculated within the quark model. In case of the electron energy spectrums, the difference between theV±A interactions are enhanced, while that in theΛ _c energy spectrums decreases. On the other hand, the

corrections are found to be negligible in both spectrums.