Decaying Neutrinos and the Flattening of the Galactic Halo

  • Dennis W. Sciama
Chapter

Abstract

The recently constructed Dehnen-Binney set of mass models for the galaxy is used to show that the decaying neutrino theory for the ionization of the interstellar medium (Sciama 1990a 1993) requires the neutrino halo of the galaxy to be as flattened as is observationally permitted (axial ratioq =0.2 or shape E8). The argument involves an evaluation of the contribution of red-shifted decay photons from the cosmological distribution of neutrinos to the extragalactic diffuse background at 1500°A. This contribution must be as large as is observationally permitted. These two requirements depend on the decay lifetime τ in potentially conflicting ways. For consistency to be achieved, τ must lie within 30% of 1023seconds.

Keywords

Dark Matter Column Density Scale Height Galactic Halo Decay Photon 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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© Springer Science+Business Media New York 1999

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  • Dennis W. Sciama

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