A one parameter representation for the Isgur-Wise function

We use a $1S$ lattice QCD heavy-light wavefunction to generate a single parameter, model independent description of the Isgur-Wise function. Using recent data we find the zero-recoil slope to be $\xi'(1)= -1.16\pm 0.17$, while the second derivative turns out to be $\xi''(1)= 2.64\pm 0.74$.