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Title: Angular Signatures of Dark Matter in the Diffuse Gamma Ray Spectrum

Abstract

Dark matter annihilating in our Galaxy's halo and elsewhere in the universe is expected to generate a diffuse flux of gamma rays, potentially observable with next generation satellite-based experiments, such as GLAST. In this article, we study the signatures of dark matter in the angular distribution of this radiation. Pertaining to the extragalactic contribution, we discuss the effect of the motion of the solar system with respect to the cosmological rest frame, and anisotropies due to the structure of our local universe. For the gamma ray flux from dark matter in our own Galactic halo, we discuss the effects of the offset position of the solar system, the Compton-Getting effect, the asphericity of the Milky Way halo, and the signatures of nearby substructure. We explore the prospects for the detection of these features by the GLAST satellite and find that, if {approx} 10% or more of the diffuse gamma ray background observed by EGRET is the result of dark matter annihilations, then GLAST should be sensitive to anisotropies down to the 0.1% level. Such precision would be sufficient to detect many, if not all, of the signatures discussed in this paper.

Authors:
; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
900368
Report Number(s):
FERMILAB-PUB-07-038-A
arXiv eprint number astro-ph/0702328; TRN: US200711%%112
DOE Contract Number:
AC02-07CH11359
Resource Type:
Journal Article
Resource Relation:
Journal Name: JCAP 0706:013,2007
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCURACY; ANGULAR DISTRIBUTION; DETECTION; MILKY WAY; NONLUMINOUS MATTER; SATELLITES; SOLAR SYSTEM; UNIVERSE; Astrophysics

Citation Formats

Hooper, Dan, Serpico, Pasquale D., and /Fermilab. Angular Signatures of Dark Matter in the Diffuse Gamma Ray Spectrum. United States: N. p., 2007. Web. doi:10.1088/1475-7516/2007/06/013.
Hooper, Dan, Serpico, Pasquale D., & /Fermilab. Angular Signatures of Dark Matter in the Diffuse Gamma Ray Spectrum. United States. doi:10.1088/1475-7516/2007/06/013.
Hooper, Dan, Serpico, Pasquale D., and /Fermilab. Thu . "Angular Signatures of Dark Matter in the Diffuse Gamma Ray Spectrum". United States. doi:10.1088/1475-7516/2007/06/013. https://www.osti.gov/servlets/purl/900368.
@article{osti_900368,
title = {Angular Signatures of Dark Matter in the Diffuse Gamma Ray Spectrum},
author = {Hooper, Dan and Serpico, Pasquale D. and /Fermilab},
abstractNote = {Dark matter annihilating in our Galaxy's halo and elsewhere in the universe is expected to generate a diffuse flux of gamma rays, potentially observable with next generation satellite-based experiments, such as GLAST. In this article, we study the signatures of dark matter in the angular distribution of this radiation. Pertaining to the extragalactic contribution, we discuss the effect of the motion of the solar system with respect to the cosmological rest frame, and anisotropies due to the structure of our local universe. For the gamma ray flux from dark matter in our own Galactic halo, we discuss the effects of the offset position of the solar system, the Compton-Getting effect, the asphericity of the Milky Way halo, and the signatures of nearby substructure. We explore the prospects for the detection of these features by the GLAST satellite and find that, if {approx} 10% or more of the diffuse gamma ray background observed by EGRET is the result of dark matter annihilations, then GLAST should be sensitive to anisotropies down to the 0.1% level. Such precision would be sufficient to detect many, if not all, of the signatures discussed in this paper.},
doi = {10.1088/1475-7516/2007/06/013},
journal = {JCAP 0706:013,2007},
number = ,
volume = ,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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