PAMELA/FERMI/HESS data on positrons may be explained in terms of solar neighbourhood WIMP annihilations primarily to leptons or muons for a few TeV mass WIMP with a Sommerfeld-corrected boost similar to 10(4) - 10(5), provided that a small component of the dark matter is in cold subhalo substructure. Saturation of the Sommerfeld effect constrains the range of contributing substructures to be above similar to 10(5) M(circle dot). Dynamical friction and tidal disruption of substructure in the inner regions of halos and subhalos play an important role in suppressing annihilations. The associated diffuse gamma ray or synchrotron signal from the inner galaxy is below current limits, but an inverse Compton contribution produced in early universe substructure annihilations is potentially detectable by FERMI as an isotropic background.
The Impact of Halo Substructure on Dark Matter Signatures / Lattanzi, Massimiliano; Joseph, Silk. - In: NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS. - ISSN 0920-5632. - 194:C(2009), pp. 162-165. (Intervento presentato al convegno Galileo-Galilei-Institute Conference on Dark Matter and Dark Energy tenutosi a Florence, ITALY nel JAN 19-MAR 12, 2009) [10.1016/j.nuclphysbps.2009.07.096].
The Impact of Halo Substructure on Dark Matter Signatures
LATTANZI, MASSIMILIANO;
2009
Abstract
PAMELA/FERMI/HESS data on positrons may be explained in terms of solar neighbourhood WIMP annihilations primarily to leptons or muons for a few TeV mass WIMP with a Sommerfeld-corrected boost similar to 10(4) - 10(5), provided that a small component of the dark matter is in cold subhalo substructure. Saturation of the Sommerfeld effect constrains the range of contributing substructures to be above similar to 10(5) M(circle dot). Dynamical friction and tidal disruption of substructure in the inner regions of halos and subhalos play an important role in suppressing annihilations. The associated diffuse gamma ray or synchrotron signal from the inner galaxy is below current limits, but an inverse Compton contribution produced in early universe substructure annihilations is potentially detectable by FERMI as an isotropic background.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
