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High Energy Physics - Phenomenology, hep-ph, Astrophysics, High Energy Astrophysical Phenomena, astro-ph.HE
Abstract:
Conversions and semi-annihilations of dark matter (DM) particles in addition
to the standard DM annihilations are considered in a three-component DM system.
We find that the relic abundance of DM can be very sensitive to these
non-standard DM annihilation processes, which has been recently found for
two-component DM systems. To consider a concrete model of a three-component DM
system, we extend the radiative seesaw model of Ma by adding a Majorana fermion
\chi and a real scalar boson \phi, to obtain a Z_2 \times Z'_2 DM stabilizing
symmetry, where we assume that the DM particles are the inert Higgs boson, \chi
and \phi. It is shown how the allowed parameter space, obtained previously in
the absence of \chi and \phi, changes. The semi-annihilation process in this
model produces monochromatic neutrinos. The observation rate of these
monochromatic neutrinos from the Sun at IceCube is estimated. Observations of
high energy monochromatic neutrinos from the Sun may indicate a multi-component
DM system.
