20,259 research outputs found
Three-generation neutrino oscillations in curved spacetime
Three-generation MSW effect in curved spacetime is studied and a brief
discussion on the gravitational correction to the neutrino self-energy is
given. The modified mixing parameters and corresponding conversion
probabilities of neutrinos after traveling through celestial objects of
constant densities are obtained. The method to distinguish between the normal
hierarchy and inverted hierarchy is discussed in this framework. Due to the
gravitational redshift of energy, in some extreme situations, the resonance
energy of neutrinos might be shifted noticeably and the gravitational effect on
the self-energy of neutrino becomes significant at the vicinities of spacetime
singularities.Comment: 25 pages, 5 figures, 2 tables. Some changes are made according to
referee's suggestions. The final version is to be published at Nuclear
Physics
Calculation of the Branching Ratio of in PQCD
The branching ratio of is re-evaluated in the PQCD approach.
In this theoretical framework all the phenomenological parameters in the
wavefunctions and Sudakov factor are priori fixed by fitting other experimental
data, and in the whole numerical computations we do not introduce any new
parameter. Our results are consistent with the upper bounds set by the Babar
and Belle measurements.Comment: 12 pages, 1 figure, version to appear in Phys. Rev.
A Comprehensive Four-Quark Interpretation of D_s(2317), D_s(2457) and D_s(2632)
The recently observed new member of the charm-strange family D_s(2632) which
has a surprisingly narrow width is challenging our theory. D_s(2317) and
D_s(2457) which were observed earlier have similar behaviors and receive
various theoretical explanations. Some authors use the heavy hadron chiral
effective theory to evaluate heavy-light quark systems and obtain a reasonable
evaluation on the masses of D_s(2317) and D_s(2457). An alternative picture is
to interpret them as four-quark or molecular states. In this work, we are
following the later and propose a unitive description for all the three new
members D_s(2632), D_s(2317) and D_s(2457) and at least, so far our picture is
consistent with the data.Comment: 6 page
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