The Isgur-Wise function in the BPS limit

F. Jugeau , A. Le Yaouanc (1) , L. Oliver (1) , J. -C. Raynal (1)

1 LPT - Laboratoire de Physique Théorique d'Orsay [Orsay]

From sum rules in the heavy quark limit of QCD, using the non-forward amplitude, we demonstrate that if the slope rho^2 = -xsi'(1) of the Isgur-Wise function xsi(w) attains its lower bound 3/4 (as happens in the BPS limit proposed by Uraltsev), the IW function is completely determined, given by the function xsi(w) = [2/(w+1)]^(3/2).

Domaines: Physique des Hautes Energies - Phénoménologie [hep-ph]

F. Jugeau, A. Le Yaouanc, L. Oliver, J. -C. Raynal. The Isgur-Wise function in the BPS limit. ICHEP 2006, Jul 2006, Moscou, Russia. pp.1040. ⟨hal-00116201⟩