173 research outputs found
Schr\"odinger Equation for Heavy Mesons Expanded in
Operating just once the naive Foldy-Wouthuysen-Tani transformation on the
Schr\"odinger equation for bound states described by a hamiltonian,
we systematically develop a perturbation theory in which enables one to
solve the Schr\"odinger equation to obtain masses and wave functions of the
bound states in any order of . It is shown that positive energy
projection with respect to the heavy quark sector of a wave function is, at
each order of perturbation, proportional to the 0-th order solution. There
appear also negative components of the wave function except for the 0-th order,
which contribute also to higher order corrections to masses.Comment: 14 pages, uses REVTeX style file
Spectroscopy and Decays of Heavy Mesons
Assuming Coulomb-like as well as confining scalar potential, we have solved
Shr\"odinger equation perturbatively in with a heavy quark mass .
The lowest order equation is examined carefully. Mass levels are fitted with
experimental data for mesons at each level of perturbation. Meson wave
functions obtained thereby can be used to calculate ordinary form factors as
well as Isgur-Wise functions for semileptonic weak decays and other physical
quantities. All the above calculations are expanded in order by order
to determine parameters as well as to compare with results of Heavy Quark
Effective Theory.Comment: 4 page
Chiral Particle Decay of Heavy-Light Mesons in a Relativistic Potential Model
Partial decay widths of the heavy-light mesons, and ,
emitting one chiral particle ( or ) are evaluated in the framework of a
relativistic potential model. Decay amplitudes are calculated by keeping the
Lorentz invariance as far as possible and use has been made of the
Lorentz-boosted relativistic wave functions of the heavy-light mesons. One of
predictions of our calculation is very narrow widths of a few keV for yet
undsicovered mesons corresponding to and
assuming their masses to be 5617 and 5682 MeV, respectively, as
calculated in our former paper. In the course of our calculation, new sum rules
are discovered on the decay widths in the limit of . Among these
rules,
and
are predicted to hold with a good accuracy.Comment: 14pages, 6table
Consistent Definitions of Flux and Electric and Magnetic Current in Abelian Projected SU(2) Lattice Gauge Theory
Through the use of a lattice U(1) Ward-Takahashi identity, one can find a
precise definition of flux and electric four-current that does not rely on the
continuum limit. The magnetic four-current defined for example by the
DeGrand-Toussaint construction introduces order a^2 errors in the field
distributions. We advocate using a single definition of flux in order to be
consistent with both the electric and magnetic Maxwell's equations at any
lattice spacing. In a U(1) theory the monopoles are slightly smeared by this
choice, i.e. are no longer associated with a single lattice cube. In Abelian
projected SU(2) the consistent definition suggests further modifications. For
simulations in the scaling window, we do not foresee large changes in the
standard analysis of the dual Abrikosov vortex in the maximal Abelian gauge
because the order a^2 corrections have small fluctuations and tend to cancel
out. However in other gauges, the consequences of our definitions could lead to
large effects which may help in understanding the choice of gauge. We also
examine the effect of truncating all monopoles except for the dominant cluster
on the profile of the dual Abrikosov vortex.Comment: 12 pages, 4 eps figures, Confinement 2003 contributed tal
Is the Z^+(4430) a radially excited state of D_s?
We present the interpretation that the recently discovered Z^+(4430) by the
Belle Collaboration can be a radial excitation of the cs-bar state. We give an
explicit cs-bar candidate for this state by calculating the mass value in our
semirelativistic quark potential model and also give a natural interpretation
on the reason why the decay mode Z-> J/\psi \pi^+ has not yet been seen while
Z-> \psi' \pi can be seen.Comment: 6 pages, 4 figure
Mixing angle between and in HQET
Some claim that there are two independent mixing angles (, ) between and states of heavy-light
mesons in heavy quark symmetric limit, and others claim there is only one
(). We clarify the difference between these two and
suggest which should be adopted. General arguments on the mixing angle between
and of heavy-light mesons are given in HQET and a general
relation is derived in heavy quark mass limit as well as that including the
first order correction in .Comment: 6 pages, 1 tabl
Decay properties of the heavy-light mesons
We study the decay properties of a heavy-light meson. We reformulate the
decay amplitudes for the heavy-light systems and find a new way to calculate
decay rates. Applying this formulation, we find a new sum rule for the
radiative decays of one heavy-light meson into another,
with various combinations of .Comment: an invited talk at "New Frontiers in QCD 2010" held at Kyot
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