Constraints on the galactic halo dark matter from fermi-lat diffuse measurements

Ackermann M.; Ajello M.; Atwood W. B.; Baldini L.; Barbiellini G.; Bastieri D.; Bechtol K.; Bellazzini R.; Blandford R. D.; Bloom E. D.; Bonamente E.; Borgland A. W.; Bottacini E.; Brandt T. J.; Bregeon J.; Brigida M.; Bruel P.; Buehler R.; Buson S.; Caliandro G. A.; Cameron R. A.; Caraveo P. A.; Casandjian J. M.; Cecchi C.; Charles E.; Chekhtman A.; Chiang J.; Ciprini S.; Claus R.; Cohen-Tanugi J.; Conrad J.; Cuoco A.; Cutini S.; D'Ammando F.; De Angelis A.; De Palma F.; Dermer C. D.; Do Couto E Silva E.; Drell P. S.; Drlica-Wagner A.; Falletti L.; Favuzzi C.; Fegan S. J.; Focke W. B.; Fukazawa Y.; Funk S.; Fusco P.; Gargano F.; Gasparrini D.; Germani S.; Giglietto N.; Giordano F.; Giroletti M.; Glanzman T.; Godfrey G.; Grenier I. A.; Guiriec S.; Gustafsson M.; Hadasch D.; Hayashida M.; Horan D.; Hughes R. E.; Jackson M. S.; Jogler T.; Johannesson G.; Johnson A. S.; Kamae T.; Knodlseder J.; Kuss M.; Lande J.; Latronico L.; Lionetto A. M.; Llena Garde M.; Longo F.; Loparco F.; Lott B.; Lovellette M. N.; Lubrano P.; Mazziotta M. N.; Mcenery J. E.; Mehault J.; Michelson P. F.; Mitthumsiri W.; Mizuno T.; Moiseev A. A.; Monte C.; Monzani M. E.; Morselli A.; Moskalenko I. V.; Murgia S.; Naumann-Godo M.; Norris J. P.; Nuss E.; Ohsugi T.; Orienti M.; Orlando E.; Ormes J. F.; Paneque D.; Panetta J. H.; Pesce-Rollins M.; Pierbattista M.; Piron F.; Pivato G.; Poon H.; Raino S.; Rando R.; Razzano M.; Razzaque S.; Reimer A.; Reimer O.; Romoli C.; Sbarra C.; Scargle J. D.; Sgro C.; Siskind E. J.; Spandre G.; Spinelli P.; Stawarz L.; Strong A. W.; Suson D. J.; Tajima H.; Takahashi H.; Tanaka T.; Thayer J. G.; Thayer J. B.; Tibaldo L.; Tinivella M.; Tosti G.; Troja E.; Usher T. L.; Vandenbroucke J.; Vasileiou V.; Vianello G.; Vitale V.; Waite A. P.; Wallace E.; Wood K. S.; Wood M.; Yang Z.; Zaharijas G.; Zimmer S.

doi:10.1088/0004-637X/761/2/91

We have performed an analysis of the diffuse gamma-ray emission with the Fermi Large Area Telescope (LAT) in the Milky Way halo region, searching for a signal from dark matter annihilation or decay. In the absence of a robust dark matter signal, constraints are presented. We consider both gamma rays produced directly in the dark matter annihilation/decay and produced by inverse Compton scattering of the e+/e- produced in the annihilation/decay. Conservative limits are derived requiring that the dark matter signal does not exceed the observed diffuse gamma-ray emission. A second set of more stringent limits is derived based on modeling the foreground astrophysical diffuse emission using the GALPROP code. Uncertainties in the height of the diffusive cosmic-ray halo, the distribution of the cosmic-ray sources in the Galaxy, the index of the injection cosmic-ray electron spectrum, and the column density of the interstellar gas are taken into account using a profile likelihood formalism, while the parameters governing the cosmic-ray propagation have been derived from fits to local cosmic-ray data. The resulting limits impact the range of particle masses over which dark matter thermal production in the early universe is possible, and challenge the interpretation of the PAMELA/Fermi-LAT cosmic ray anomalies as the annihilation of dark matter. © 2012. The American Astronomical Society. All rights reserved.