相关论文: Sum rules in the heavy quark limit of QCD and Isgu…
Using the OPE and the trace formalism, we have obtained a number of sum rules in the heavy quark limit of QCD that include the sum over all excited states for any value $j^P$ of the light cloud. We show that these sum rules imply that the…
Using the OPE, we obtain new sum rules in the heavy quark limit of QCD, in addition to those previously formulated. Key elements in their derivation are the consideration of the non-forward amplitude, plus the systematic use of boundary…
In the leading order of the heavy quark expansion, we propose a method within the OPE and the trace formalism, that allows to obtain, in a systematic way, Bjorken-like sum rules for the derivatives of the elastic Isgur-Wise function…
In the heavy quark limit of QCD, using the Operator Product Expansion, the formalism of Falk for hadrons or arbitrary spin, and the non-forward amplitude, as proposed by Uraltsev, we formulate sum rules involving the Isgur-Wise function…
We consider the dominant $c\bar{c}$ contribution to $\Delta \Gamma$ for the $B_s^0$-$\bar{B}_s^0$ system in the heavy quark limit for both $b$ and $c$ quarks. In analogy with the Bjorken-Isgur-Wise sum rule in semileptonic heavy hadron…
Considering nonforward scattering amplitude off the heavy quark in the Small Velocity limit two exact superconvergent sum rules are derived. The first sum rule leads to the lower bound \rho^2 > 3/4 for the slope of the Isgur-Wise function.…
In a preceeding study in the heavy quark limit of QCD, it has been demonstrated that the best lower bound on the curvature of the Isgur-Wise function Xsi(w) is Xsi"(1) > (4rho2+3(rho2)2) > 15/16. The quadratic term (rho2)2 is dominant in a…
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…
Using previously formulated sum rules in the heavy quark limit of QCD, we demonstrate that if the slope rho^2 = -xi'(1) of the Isgur-Wise function xi(w) attains its lower bound 3/4, then all the derivatives (-1)^L xi^(L)(1) attain their…
Radiative corrections to both perturbative and non-perturbative contributions are added to existing calculations of the Isgur-Wise function $\xi_{IW}$. To this end, we develop a method for calculating two-loop integrals in the heavy quark…
Within the OPE, we the new sum rules in Heavy Quark Effective Theory in the heavy quark limit and at order 1/m_Q, using the non-forward amplitude. In particular, we obtain new sum rules involving the elastic subleading form factors chi_i(w)…
We show that the sum rule recently proved by Uraltsev in the heavy quark limit of QCD holds in relativistic quark models \`a la Bakamjian and Thomas, that were already shown to satisfy Isgur-Wise scaling and Bjorken sum rule. This new sum…
In the heavy quark limit of QCD, using the Operator Product Expansion and the non-forward amplitude, as proposed by Nikolai Uraltsev, we formulate sum rules that generalize Bjorken and Uraltsev sum rules. We recover the Uraltsev lower bound…
Two new sum rules were recently discovered by Le Yaouanc et al. by applying the operator product expansion to the nonforward matrix element of a time-ordered product of $b \to c$ currents in the heavy-quark limit of QCD. They lead to the…
We construct the Isgur-Wise limit of QCD in a form appropriate to lattice gauge theory techniques. The formulation permits a calculation of heavy quark processes even when the momentum transfers are much larger than the inverse lattice…
Sum rules based upon heavy quark effective theory indicate that the Isgur-Wise function $\xi(w)$ has a minimum slope as w approaches 1, which is zero for light degrees of freedom with zero spin and 1/4 for light spin 1/2. Quark-model…
We discuss constraints imposed on the zero-recoil curvature and higher derivatives of the Isgur-Wise function by a general quark model. These constraints are expressed as bounds for a given slope parameter, and compared with those based…
We pursue the program of the study of the non-forward amplitude in HQET. We obtain new sum rules involving the elastic subleading form factors $\chi_i(w)$ $(i = 1,2, 3)$ at order $1/m_Q$ that originate from the ${\cal L}_{kin}$ and ${\cal…
We use the Dirac equation with a ``(asymptotically free) Coulomb + (Lorentz scalar) linear '' potential to estimate the light quark wavefunction for $ q\bar Q$ mesons in the limit $m_Q\to \infty$. We use these wavefunctions to calculate the…
The QCD inspired potential model persued by us earlier has been recently modified to incorporate an additional factor 'c' in the linear cum Coulomb potential. While it felicitates the inclusion of standard confinement parameter b = 0.183GeV…