Thermal and annihilation radiation in the quark nugget model of dark
  matter
  The Quark Nugget (QN) model of dark matter suggests that the dark matter may
consist of compact composite objects of quark matter. Although such composite
particles can strongly interact with visible matter, they may remain undetected
because of a small cross section to mass ratio. We focus on anti-QNs made of
antiquarks since they are heated by annihilation with visible matter and
radiate. We study the radiation spectrum and power from anti-QNs in our galaxy
and compare them with satellite observations. Thermal radiation from anti-QN is
produced by fluctuations of the positron density. We calculate the thermal
radiation of anti-QNs with the use of the Mie theory and found its ratio to the
black-body radiation. This allows us to find the equilibrium temperature of
anti-QNs in the interstellar medium and determine their contribution to the
observed diffuse background radiation in our galaxy in different frequency
intervals, from radio to UV. We also consider non-thermal radiations from
anti-QNs which are produced by products of annihilations of particles of the
interstellar gas with anti-QNs. Such radiations include photons from decays of
$\pi^0$ mesons, synchrotron, bremsstrahlung and transition radiations from
$\pi^\pm$ mesons, electrons and positrons. Synchrotron radiation in MHz
frequency range and flux of photons from $\pi^0$ decays may be above the
detection threshold in such detectors as Fermi-LAT.
