6 research outputs found
F-theory Compactifications for Supersymmetric GUTs
We construct a family of elliptically fibered Calabi-Yau four-folds Y_4 for
F-theory compactifications that realize SU(5) GUTs in the low-energy limit. The
three-fold base X_3 of these fibrations is almost Fano and satisfies the
topological criteria required to ensure that the U(1)_Y gauge boson remains
massless, while allowing a decoupling of GUT and Planck scale physics. We study
generic features of these models and the ability to engineer three chiral
generations of MSSM matter. Finally, we demonstrate that it is relatively easy
to implement the topological conditions required to reproduce certain
successful features of local F-theory models, such as the emergence of flavor
hierarchies.Comment: 55 pages, 10 figure
Radiative Scalar Meson Decays in the Light-Front Quark Model
We construct a relativistic wavefunction for scalar mesons within the
framework of light-front quark model(LFQM). This scalar wavefunction is used to
perform relativistic calculations of absolute widths for the radiative decay
processes, and
which incorporate the effects of glueball-
mixing. The mixed physical states are assumed to be ,and
for which the flavor-glue content is taken from the mixing
calculations of other works. Since experimental data for these processes are
poor, our results are compared with those of a recent non-relativistic model
calculation. We find that while the relativistic corrections introduced by the
LFQM reduce the magnitudes of the decay widths by 50-70%, the relative
strengths between different decay processes are fairly well preserved. We also
calculate decay widths for the processes and
(0^{++})\to\gamma\gamm involving the light scalars and
to test the simple model of these mesons. Our results of
model for these processes are not quite consistent with well-established data,
further supporting the idea that and are not conventional
states.Comment: 10 pages, 4 figure