78 research outputs found
Magnetic moments of octet baryons and sea antiquark polarizations
Using generalized Sehgal equations for magnetic moments of baryon octet and
taking into account mixing and two particle corrections to
independent quark contributions we obtain very good fit using experimental
values for errors of such moments. We present sum rules for quark magnetic
moments ratios and for integrated spin dendities ratios. Due to the SU(3)
structure of our equations the results for magnetic moments of quarks and their
densities depend on two additional parameters. Using information from deep
inelastic scattering and baryon -decays we discuss the dependence of
antiquark polarizations on introduced parameters. For some plausible values of
these parameters we show that these polarizations are small if we neglect
angular momenta of quarks. Our very good fit to magnetic moments of baryon
octet can still be improved by using specific model for angular momentum of
quarks.Comment: Latex, 19 pages 5 eps figures, 2 references added, changes in text to
apear in Phys. Rev.
A possible glueball contribution to the Goldberger-Treiman relations
We discuss the influence of glueball coupling to nucleons on the weak
axial-vector coupling constants including singlet channel. We consider a
possibility of introduction of constituent gluon contribution to the proton
spin. The estimated value for this quantity seems to be rather small.Comment: 7 pages, Latex,(missing table), CAMK 256 199
Magnetic moments of octet baryons, angular momenta of quarks and sea antiquark polarizations
One can determine antiquark polarizations in proton using the information
from deep inelastic scattering, decays of baryons, orbital angular
momenta of quarks, as well as their integrated magnetic distributions. The last
quantities were determined previously by us performing a fit to magnetic
moments of baryon octet. However, because of the SU(3) symmetry our results
depend on two parameters. The quantity , measured recently in a
COMPASS experiment, gives the relation between these parameters. We can fix the
last unknown parameter using the ratio of up and down quark magnetic moments
which one can get from the fit to radiative vector meson decays. We calculate
antiquark polarizations with the orbital momenta of valence quarks that follow
from lattice calculations. The value of difference for up and down antiquark
polarizations obtained in our calculations is consistent with the result
obtained in a HERMES experiment.Comment: 14 pages, latex, 5 eps figure
Triangular mass matrices for quarks and leptons
We assume that all quark and lepton mass matrices which appear
in the standard model lagrangian (after spontaneous symmetry breaking) with
neutrinos treated as Dirac patricles have the triangular form. Such matrices
have not only less non-zero elements (three of them are equal to zero) but also
lead to very asymmetrical decomposition into one diagonal and two unitary
matrices for quarks and leptons. We also assume that unitary matrices which
transform flavor into definite mass states for right handed components (weakly
non-interacting) in the same weak isodoublet are equal. Using all available
experimental data on quark and lepton masses and mixing angles, treating in the
universal way quarks and leptons, we determine the triangular mass matrices for
up and down type quarks, neutrinos and charged leptons and as a consequence
mixing matrices for left-handed and right handed components. As the result of
the fit we get predictions for the neutrino masses including smallest neutrino
mass. The calculations without CP violation and with inclusion of this effect
in quark sector are also presented.Comment: 12 pages, no figure
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