2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/199341We present a calculation of the form factor for B -> D* l nu using a 2+1 improved staggered action for the light quarks (on the MILC configurations), and the Fermilab action for the heavy quarks. The form factor is computed at zero recoil using a new double ratio method which yields the form factor more directly than previous approaches.7 pages, 3 figures; proc. of the XXV International Symposium on Lattice Field Theory, July 30 - August 4, 2007, Regensburg, GermanyHigh Energy Physics - Latticetext