10 research outputs found
Measuring at future B-Factories
We calculate the so--called Fermi motion parameter of ACCMM model
using the variational method in a potential model approach. We also propose
hadronic invariant mass distribution as an alternative experimental observable
to measure at future asymmetric factories.Comment: 9 pages (1 fugure not included
Decay Constants of Heavy Meson of State in Relativistic Salpeter Method
The decay constants of pseudoscalar heavy mesons of state are computed
by means of the relativistic (instantaneous) Salpeter equation. We solved the
full Salpeter equation without making any further approximation, such as
ignoring the small component wave function. Therefore, our results for the
decay constants include the complete relativistic contributions from the light
and the heavy quarks. We obtain , , , , and MeV.Comment: 9 pages, 1 figur
New Approach for Measuring at Future -Factories
It is suggested that the measurements of hadronic invariant mass ()
distributons in the inclusive decays can be
useful in extracting the CKM matrix element . We investigated
hadronic invariant mass distributions within the various theoretical models of
HQET, FAC and chiral lagrangian as well as ACCMM model. It is also emphasized
that the distribution even at the region in the inclusive
are effetive in selecting the events, experimentally viable at
the future asymmetric factories, with better theoretical understandings.Comment: 11 pages not including 1 figur
Dependence of on Fermi momentum in ACCMM model
The Gaussian width of Fermi momentum, , is the most important
parameter of the ACCMM model, and its value is essential in the determination
of because the experimental analysis is allowed only at the
end-point region of inclusive semileptonic -decay spectrum. We extract the
value of as a function of . We also calculate the
parameter in the relativistic quark model using the variational
method, and obtain GeV which is much larger than the commonly
used value, GeV, in experimental analyses. When we use GeV instead of 0.3 GeV, the value of from ACCMM model is
increased by a factor 1.81, and can give a good agreement with Isgur {\it et
al.} model.Comment: 1. Section 2 has been revised by considering the fact that in the
real experimental situation the only measured quantity is the number of
events in the high region compared to the total semi- leptonic event
number. 2. The article by C. Greub and D. Wyler (Phys. Lett. B295 (1992) 293)
has been included in references, which reports a similar conclusion for the
value of (=566 MeV), even though they used the different
approach. 3. This article will be published in Z. Phys. C (1995
Decay Constants and Semileptonic Decays of Heavy Mesons in Relativistic Quark Model
We investigate the and mesons in the relativistic quark model by
applying the variational method with the Gaussian wave function. We calculate
the Fermi momentum parameter , and obtain
GeV, which is almost independent of the input parameters, , ,
and . We then calculate the ratio /, and obtain the
result which is larger, by the factor of about 1.3, than
given by the naive nonrelativistic analogy. This result is in a good agreement
with the recent Lattice calculations. We also calculate the ratio
/. In these calculations the wave function at
origin is essential. We also determine by comparing the
theoretical prediction of the ACCMM model with the lepton energy spectrum of from the recent ARGUS analysis, and find that
GeV, when we use GeV. However, this
experimentally determined value of is strongly dependent on the value
of input parameter .Comment: 15 pages (Latex) (uses epsfig.sty, 1 figure appended as a uuencoded
compressed ps-file
Average Kinetic Energy of Heavy Quark and Virial Theorem
We derive the virial theorem of the relativistic two-body system for the
study of the B-meson physics. It is also shown that the solution of the
variational equation always satisfies the virial theorem. From the virial
theorem we also obtained GeV, which is consistent with the result of the QCD sum rule
calculations of Ball Comment: 13 pages. A lot of parts of the manuscript have been revised. To
appear in Physics Letters
Average Kinetic Energy of Heavy Quark in Semileptonic B Decay
Within the ACCMM model the average kinetic energy of heavy quark in a
heavy-light meson is calculated as , solely from the fact that the Gaussian momentum probability
distribution has been taken in the ACCMM model. Therefore, the Fermi momentum
parameter of the ACCMM model is not a truly free parameter, but is
closely related to the average kinetic energy of heavy quark, which is
theoretically calculable in principle. In this context, we determine
by comparing the theoretical prediction of the ACCMM model with the model
independent lepton energy spectrum of from the recent
CLEO analysis, and find that GeV. We also
calculate in the relativistic quark model by applying the quantum
mechanical variational method, and obtained GeV. We show
the correspondences between the relativistic quark model and the heavy quark
effective theory. We then clarify the importance of the value of in
the determination of .Comment: 23 pages(LaTeX), 2 Postscript figures, uses aps.st