High-energy neutrinos from the sun and cold dark matter

We consider in detail the possibility of a flux of high-energy neutrinos from the sun due to the annihilation within of particles which make up the galactic halo. Specifically, if the halo consists of heavy neutrinos or stable supersymmetric particles with mass ≳6 GeV, halo particles will be trapped in the sun and annihilate to produce a potentially observable high-energy neutrino flux. We provide detailed estimates of this flux for a variety of candidate halo particles: photinos, higgsinos, scalar neutrinos, heavy Dirac neutrinos, and heavy Majorana neutrinos. All of these can (for appropriate ranges of parameters) produce fluxes whose absolute value is at least comparable to atmospheric background. We briefly discuss how the solar fluxes could be distinguished from the background. We also discuss the effect of trapped halo particles on the solar neutrino problem.