Gamma Ray and Neutrino Flux from Annihilation of Neutralino Dark Matter at Galactic Halo Region in mAMSB Model

Journal of Physics G Nuclear and Particle Physics (Impact Factor: 2.78). 05/2012; 40:075201. DOI: 10.1088/0954-3899/40/7/075201
Source: arXiv


We consider the lightest supersymmetric particle (LSP), neutralino in minimal
anomaly mediated supersymmetry breaking model (mAMSB) to be a possible
candidate for weakly interacting massive particles (WIMP) or cold dark matter
and investigate its direct and indirect detections. The theoretically allowed
supersymmetric parametric space for such a model along with the recent bounds
from LHC is constrained by the WMAP results for relic densities. The spin
independent and spin dependent scattering cross sections for dark matter off
nucleon are thus constrained from the WMAP results. They are found to be within
the allowed regions of different ongoing direct detection experiments. The
annihilation of such dark matter candidates at the galactic centre produce
different standard model particles such as gamma rays, neutrinos etc. In this
work, we calculate the possible fluxes of these $\gamma$-rays and neutrinos
coming from the direction of the galactic centre (and its neighbourhood) at
terrestrial or satellite borne detectors. The calcutated $\gamma$-ray flux is
compared with the observational results of HESS experiment. The neutrino flux
of different flavours from the galactic centre and at different locations away
from the galactic centre produced by WIMP annihilation in this model are also
obtained for four types of galactic dark matter halo profiles. The detection
prospects of such $\nu_\mu$ coming from the direction of the galactic centre at
the ANTARES under sea detector are discussed in terms of muon signal yield from
these muon neutrinos. Both the gamma and neutrino signals are estimated for
four different dark matter halo profiles.

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