Cosmic Ray Backgrounds for Dark Matter Indirect Detection

par Philipp Mertsch (Oxford)

jeudi 9 déc. 2010, 11:00 → 12:00 Europe/Paris

Auditorium M. Vivargent (LAPTH)

Indirect detection of dark matter requires firm control over the backgrounds from galactic cosmic rays. The dark matter interpretation of the anomalous positron abundance detected by PAMELA relies on the assumption that positrons can otherwise be produced only through spallation of primary cosmic rays as they propagate through the galaxy. We show using FERMI and HESS data that a second background contribution from positrons accelerated by nearby supernova remnant shocks can account for the excess, thereby removing the need for dark matter. We also discuss the 'WMAP haze' (and a possible counterpart in gamma-rays) which too has been interpreted as a signature of dark matter, and demonstrate large systematic uncertainties in both signals.

Slides Mertsch