Number 446 (Story #1), September 1, 1999 by Phillip F. Schewe and Ben Stein
DARK MATTER ANNIHILATION AT THE GALACTIC CENTER. How does the presumed massive black hole at the center of our galaxy shape the distribution of the presumed halo of dark matter in its vicinity? Paolo Gondolo of the Max Planck Institute of Physics (Munich, Germany) and Joseph Silk of Oxford (UK; also UC Berkeley) suggest the black hole sculpts the dark matter into a dense spike where particle annihilation (or, more to the point, self-annihilation, since one of the leading hypothetical dark-matter particles is the "neutralino", which is its own antiparticle) would be enhanced. Of all the annihilation products (e.g., electrons, positrons, protons, etc.) issuing from the galactic center (a region half a light year wide) neutrinos would be the most serviceable since they can travel to Earth undeflected by magnetic fields. Gondolo and Silk have calculated how present and future neutrino telescopes can probe the density of inner halo dark matter. (Physical Review Letters, 30 August; gondolo@mppmu.mpg.de, 011-49-893-235-4427.)
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