Neutrinos from WIMP annihilation in the Sun : Implications of a self-consistent model of the Milky Way's dark matter halo

Physical review D: Particles and fields (Impact Factor: 4.86). 06/2011; 85(12). DOI: 10.1103/PhysRevD.85.123533
Source: arXiv


Upper limits on the spin-independent (SI) as well as spin-dependent (SD)
elastic scattering cross sections of WIMPs with protons, imposed by the
Super-Kamiokande (S-K) upper limit on the neutrino flux from WIMP annihilation
in the Sun, and their compatibility with the "DAMA-compatible" regions of the
WIMP parameter space within which the annual modulation signal observed by the
DAMA/LIBRA experiment is compatible with the null results of other direct
detection experiments, are studied within the frame work of a self-consistent
model of the finite-size dark matter (DM) halo of the Galaxy, the parameters of
which are determined by a fit to the rotation curve data of the Galaxy. We find
that the S-K implied upper limits on the WIMP-proton elastic cross section as a
function of WIMP mass impose stringent restrictions on the branching fractions
of the various WIMP annihilation channels. For SI interaction, while the S-K
upper limits are consistent with the DAMA-compatible region of the WIMP
parameter space if the WIMPs annihilate dominantly to $\bbarb$\ and/or
$\cbarc$, portions of the DAMA-compatible region can be excluded if WIMP
annihilations to $\tautau$ and $\nu\anu$ occur at larger than ~ 10% and 0.1%
levels, respectively. For SD interaction, the restrictions on the possible
annihilation channels are much more stringent, essentially ruling out the
DAMA-compatible region of the WIMP parameter space if the relatively low-mass
($\sim$ 2 -- 20 GeV) WIMPs under consideration annihilate predominantly to any
mixture of $\bbarb$, \ $\cbarc$, \ $\tautau$, \ and $\nu\anu$ final states.

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Available from: Pijushpani Bhattacharjee
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