Light-front heavy-quark effective theory and heavy-meson bound states.

Abstract

The heavy quark effective theory is developed on the light-front. Based on this effective theory, a light-front heavy meson bound state with definite spin and parity is constructed. Within the effective theory, the Isgur-Wise function is derived in terms of the asymptotic light-front bound state amplitudes in the limit $m_Q\rightarrow\infty$; the result is a general expression for arbitrary recoil velocities. With the asymptotic form of the BSW amplitudes, the Isgur-Wise function is given by $\xi(v\cdot v')=1/v\cdot v'$. The slope at the zero-recoil point is $\rho^2=-\xi'(1)=1$, in excellent agreement with the recent CLEO result of $\rho^2=1.01\pm0.15\pm0.09$.