Amount of antiprotons in cosmic rays due to halo neutralino annihilation

Abstract

We evaluate the antiproton-to-proton flux ratio which can be generated by neutralino-neutralino annihilation in the galactic halo, considering the most general compositions for the relic neutralinos and modelling the neutralino local density according to its relic abundance. We find that in the case of mixed neutralino compositions this p/p ratio is higher than for pure higgsinos or gauginos. It is shown how the expected improvements in sensitivity for the new measurements of thep/p may provide very useful information, complementary to the one obtainable with other experimental means.( to appear in Astroparticle Physics )

Full one-loop calculation of neutralino annihilation into two photons

“…6 we show the value of vσ 2g for the scan of low-mass neutralino models using our results compared to those obtained with previous formulas [25]. As can be seen, our prediction is for most of the models below the previous ones, which could make the indirect method of antiproton detection [43] more difficult than previously thought.…”

The soft supersymmetry-breaking Lagrangian: theory and applications

“…Examples include gamma rays [514,515,516,517,518,519,520,521,522,523,524,525,526], lower energy photons such as radiowaves [516,527], and antimatter such as positrons and antiprotons [514,528,529,530,531,532,533,534,535]. The source of these cosmic rays will be concentrated towards the center of our galaxy.…”

Further investigation of a relic neutralino as a possible origin of an annual-modulation effect in weakly interacting massive particle direct search

“…The possibility that annihilation of relic particles in the galactic halo might distort the spectrum of cosmic-ray antiprotons at low-kinetic energies (Tp < ∼ 1 GeV) has been considered by many authors [47][48][49][50]. Indeed, in this energy range, the production of secondary antiprotons by interactions of primary cosmic-ray protons with the interstellar hydrogen has a kinematical drop off [51], which primaryp's, created by relic neutralinos of appropriate mass and composition, might fill in, at least partially.…”