Isgur–Wise function and a new approach to potential model

Abstract

Considering the Cornell potential V (r) = − 4αs 3r + br + c, we have revisited the Dalgarno's method of perturbation by incorporating two scales r short and r long as integration limit so that the perturbative procedure can be improved in a potential model. With the improved version of the wave function the ground state masses of the heavy-light mesons D, D s , B, B s and B c are computed. The slopes and curvatures of the form factors of semi-leptonic decays of heavy-light mesons in both HQET limit and finite mass limit are calculated and compared with the available data.

2S and 3S State Masses and decay constants of heavy-flavour mesons in a non-relativistic QCD potential model with three-loop effects in V-scheme

“…O level respectively. We make a comprehensive comparison of our results with QCD sum rule [1,2], Lattice results [3,19,43,44] other models like [24], RHCM [53] and the recent experimental values [36].…”

“…M P(Our) RHCM [53] R e f . [ 24] Lattice [3] Q .s u mr u l e [ 1,2] Exp. M P [36,[45][46][47] D(cu/cd) 1 [47] B s (sb) 0.107 0.600 0.232 ± 0.018 0.228 ± 0.010 0.237 ± 0.017 [47] B c (bc) 0.311 0.607 0.562 [48] [47] B s (sb) 0.087 0.600 0.232 ± 0.018 0.228 ± 0.010 0.237 ± 0.017 [47] B c (bc) 0.09 0.607 0.562 [48]…”

“…The most common perturbative method is Dalgarno's perturbation theory (DPT) [21,[23][24][25], which is a stationary static perturbation theory. The non-relativistic potential model has been found successful for heavy-heavy B, η c and η b families.…”

“…One aim of the present work is to make an analysis of the contribution of three-loop effects in the improved strong coupling constant α V ( 1 r ) in V -scheme, which in turn contributes to the spin-spin interaction [27][28][29] term present in the expression of mass and decay constant of the heavy-flavour meson. In addition, the non-relativistic binding energy effect between the two quark-antiquark composition of the heavyflavour meson is newly incorporated in the expression of PSM mass, which was absent in our some previous works [23][24][25]37,39,41].…”

Another Look at Flavor

“…We note that employing a different value for m L simply produces a different value for ξ 2 , a phenomenological constant, equivalent to a slope change that does not affect our major qualitative conclusions. The quark mass could be any number of values of course; yet we pick a constituent quark mass value not inconsistent with many potential models [2]. Again, choosing another value for m L will produce a corresponding different value for ξ 2 (the coupling constant and slope of the attractive 1/r potential).…”