Lattice measurement of the Isgur-Wise functions $\tau_{1/2}$ and $\tau_{3/2}$

Benoit Blossier (1) , Damir Beciveriv (1) , Philippe Boucaud (1) , Gregorio Herdoiza (2) , Jean-Pierre Leroy (1) , Alain Le Yaouanc (1) , Vincent Morenas (3) , Olivier Pene (1)

1 LPT - Laboratoire de Physique Théorique d'Orsay [Orsay]
2 Dipartimento de Fisica, Università degli studi di Roma II
3 LPC - Laboratoire de Physique Corpusculaire - Clermont-Ferrand

We propose a method to compute the Isgur-Wise form factors tau_1/2(1) and tau_3/2(1) for the decay of B mesons into orbitally excited (P wave) D** charmed mesons on the lattice in the static limit. We also present the result of an exploratory numerical simulation which shows that the signal/noise ratio allows for a more dedicated computation. We find tau_1/2(1)=0.38(5) and tau_3/2(1)= 0.53(8), with yet unknown systematic errors. These preliminary numbers agree fairly well with theoretical expectation.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

Benoit Blossier, Damir Beciveriv, Philippe Boucaud, Gregorio Herdoiza, Jean-Pierre Leroy, et al.. Lattice measurement of the Isgur-Wise functions $\tau_{1/2}$ and $\tau_{3/2}$. Physics Letters B, 2005, 609, pp.298-308. ⟨10.1016/j.physletb.2005.01.054⟩. ⟨hal-00008519⟩