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Cosmic-Ray Electrons, Pulsars, and Dark Matter
Martin Pohl (Iowa State University)
Special Seminar, Seminar Room 3, 16:00
In the last months new measurements of the local cosmic-ray electron
and positron spectra were published, indicating an excess of particles at a
few 100 GeV that may be related to dark-matter annihilation. Some data in
particular suggested a narrow-band source of a pairs may exist in the Galaxy,
such as Klein-Kaluza dark matter. To distinguish a dark-matter signal from that
of, e.g., pulsars, care must be exercised to properly account for the
propagation of the electrons and positrons from their sources to our detectors.
Both pulsars and dark-matter clumps are quasi-pointlike and few, and
therefore their electron contributions at Earth generally have spectra that
deviate from the average spectrum one would calculate for a smooth source
distribution. Consequently, the spectral shape of the electron excess is
insufficient to discriminate a dark-matter origin from more conventional
astrophysical explanations.
