263,799 research outputs found
SIMP dark matter and its cosmic abundances
We give a review on the thermal average of the annihilation cross-sections
for and general higher-order processes. Thermal average of
higher order annihilations highly depend on the velocity of dark matter,
especially, for the case with resonance poles. We show such examples for scalar
dark matter in gauged models.Comment: 5 pages, 2 figures, Prepared for the proceedings of the 13th
International Conference on Gravitation, 3-7 July 201
Cosmic abundances of SIMP dark matter
Thermal production of light dark matter with sub-GeV scale mass can be
attributed to self-annihilation processes. We consider the
thermal average for annihilation cross sections of dark matter at and general higher-order interactions. A correct thermal average for initial
dark matter particles is important, in particular, for annihilation cross
sections with overall velocity dependence and/or resonance poles. We apply our
general results to benchmark models for SIMP dark matter and discuss the
effects of the resonance pole in determining the relic density.Comment: 21 pages, 6 figures, Version to appear in Journal of High Energy
Physic
Communication with SIMP dark mesons via Z'-portal
We consider a consistent extension of the SIMP models with dark mesons by
including a dark U(1)_D gauge symmetry. Dark matter density is determined by a
thermal freeze-out of the self-annihilation process, thanks to the
Wess-Zumino-Witten term. In the presence of a gauge kinetic mixing between the
dark photon and the SM hypercharge gauge boson, dark mesons can undergo a
sufficient scattering off the Standard Model particles and keep in kinetic
equilibrium until freeze-out in this SIMP scenario. Taking the
SU(N_f)xSU(N_f)/SU(N_f) flavor symmetry under the SU(N_c) confining group, we
show how much complementary the SIMP constraints on the parameters of the dark
photon are for current experimental searches for dark photon.Comment: 16 pages, 6 figures, To appear in Phys. Lett.
Inflection point inflation and reheating
We revisit the inflection point inflation with an extended discussion to
large field values and consider the reheating effects on the inflationary
predictions. Parametrizing the reheating dynamics in terms of the reheating
temperature and the equation of state during inflation, we show how the
observationally favored parameter space of inflection point inflation is
affected by reheating dynamics. Consequently, we apply the general results to
the inflation models with non-minimal coupling, such as the SM Higgs inflation
and the Higgs inflation.Comment: 27 pages, 8 figures, Improved discussion on general inflection point
inflatio
Mass and Isotope Dependence of Limiting Temperatures for Hot Nuclei
The mass and isotope dependence of limiting temperatures for hot nuclei are
investigated. The predicted mass dependence of limiting temperatures is in good
agreement with data derived from the caloric curve data. The predicted isotope
distribution of limiting temperatures appears to be a parabolic shape and its
centroid is not located at the isotope on the -stability line(T=0) but
at neutron-rich side. Our study shows that the mass and isotope dependence of
limiting temperatures depend on the interaction and the form of surface tension
and its isopin dependence sensitively.Comment: 14 pages,11 figure
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