Ds semileptonic decay in the quark model

Abstract

We discuss the semileptonic decays of the Ds meson in the quark potential model1). This model has been used to calculate semileptonic decays of B- and D-mesons which are used to extract values for the heavy-quark CKM matrix elements2). Our predictions generally agree with the data; however, recent results on D → K∗e+ νe from the E691 experiment3) show large discrepancies from the predicted values both in the partial width and the ratio of longitudinal to transverse K∗ production. As Ds → φe+ν is identical to D → K∗e+ν at the free quark level, this discrepancy makes measurements of Ds → φe+ν particularly interesting.