Cosmic ray antimatter from supersymmetric dark matter

Abstract

In this paper we study the antiproton, positron and gamma-ray fluxes resulting from the annihilation of supersymmetric dark matter in our galactic halo. We show that the requirement of closure imposed by inflationary cosmologies constrains the supersymmetric dark matter to be either a relatively pure photino eigenstate or a relatively pure higgsino eigenstate, or possibly a scalar neutrino with a mass less than 4 GeV. The photino choice can lead to observable fluxes when sfermion masses are [lsim] 50-60 GeV. Such a scenario is testable via the radiative production of photinos at PEP and PETRA. The higgsino scenario leads to observable fluxes independent of sfermion masses, provided H01|0>/H02|0> = v1/v2 [gsim] 2. In constrast, sneutrino dark matter annihilates almost entirely into neutrinos, resulting in a monochromatic neutrino flux that is probably unobservable.