14 research outputs found
Couplings of heavy mesons with soft pions in QCD
QCD sum rules are used to calculate the couplings of heavy-light quark
pseudoscalar and vector mesons ( and ) with soft pions, both
for finite and infinitely heavy quark mass. The couplings are also computed in
the framework of a QCD relativistic potential model; in this approach the
relativistic corrections due to the light quark are relevant.Comment: LaTex, 3 pages, requires the file espcrc2.sty, appended at the end.
Talk given at the workshop "QCD-94", Montpellier, France, July 7 -13, 1994.
BARI-TH/94-18
On the coupling of heavy mesons to pions in QCD
We compute the strong coupling constant , with and
respectively pseudoscalar and vector heavy mesons by using the QCD sum rules
approach. Our computation is based on the evaluation of the time ordered
product of currents between the vacuum and the soft pion state. The so-called
parasitic terms are taken into account and give a contribution to the sum rule
of the same order of the lowest lying state, while higher dimension non
perturbative terms have small numerical effects. The infinite heavy quark mass
limit is also examined.Comment: 11 pages, LaTeX, UGVA-DPT 1994/06-856 and BARI-TH/94-17
Strong coupling of excited heavy mesons
We compute the strong coupling constant , where () is the wave state, by QCD sum rules and by light-cone sum rules. The two methods give
compatible results in the limit , with a rather large value of
the coupling constant. We apply the results to the calculation of the hadronic
widths of the positive parity and states and to the chiral loop
contribution to the ratio .Comment: 31 pages, RevTeX, 4 figures appended as uuencoded fil
On the Quark Kinetic Energy in the
We consider the problem of determining the matrix element of the heavy quark
kinetic energy operator between baryonic states by three point
function QCD sum rules in the Heavy Quark Effective Theory. We discuss the main
features and the uncertainties associated to such an approach. Numerically, we
find the result: . Within the uncertainty of the method, such result indicates a value of
the heavy quark kinetic energy in the baryon similar in size to that in the
meson.Comment: RevTex, 13 pages + 3 uuencoded figures. Figures and comments on high
dimension operators adde