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Title: Gamma Rays from Heavy Neutralino Dark Matter

Abstract

We consider the gamma-ray spectrum from neutralino dark matter annihilations and show that internal bremsstrahlung of W pair final states gives a previously neglected source of photons at energies near the mass of the neutralino. For masses larger than about 1 TeV, and for present day detector resolutions, this results in a characteristic signal that may dominate not only over the continuous spectrum from W fragmentation, but also over the {gamma}{gamma} and {gamma}Z line signals which are known to give large rates for heavy neutralinos. Observational prospects thus seem promising.

Authors:
; ; ;  [1]
  1. Department of Physics, Stockholm University, AlbaNova University Center, SE - 106 91 Stockholm (Sweden)
Publication Date:
OSTI Identifier:
20699666
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 95; Journal Issue: 24; Other Information: DOI: 10.1103/PhysRevLett.95.241301; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANNIHILATION; COSMOLOGY; GAMMA ASTRONOMY; GAMMA RADIATION; GAMMA SPECTRA; INTERNAL BREMSSTRAHLUNG; NONLUMINOUS MATTER; NUCLEAR FRAGMENTATION; PHOTONS; SIGNALS; SPARTICLES; TEV RANGE 01-10

Citation Formats

Bergstroem, Lars, Bringmann, Torsten, Eriksson, Martin, and Gustafsson, Michael. Gamma Rays from Heavy Neutralino Dark Matter. United States: N. p., 2005. Web. doi:10.1103/PhysRevLett.95.241301.
Bergstroem, Lars, Bringmann, Torsten, Eriksson, Martin, & Gustafsson, Michael. Gamma Rays from Heavy Neutralino Dark Matter. United States. doi:10.1103/PhysRevLett.95.241301.
Bergstroem, Lars, Bringmann, Torsten, Eriksson, Martin, and Gustafsson, Michael. Fri . "Gamma Rays from Heavy Neutralino Dark Matter". United States. doi:10.1103/PhysRevLett.95.241301.
@article{osti_20699666,
title = {Gamma Rays from Heavy Neutralino Dark Matter},
author = {Bergstroem, Lars and Bringmann, Torsten and Eriksson, Martin and Gustafsson, Michael},
abstractNote = {We consider the gamma-ray spectrum from neutralino dark matter annihilations and show that internal bremsstrahlung of W pair final states gives a previously neglected source of photons at energies near the mass of the neutralino. For masses larger than about 1 TeV, and for present day detector resolutions, this results in a characteristic signal that may dominate not only over the continuous spectrum from W fragmentation, but also over the {gamma}{gamma} and {gamma}Z line signals which are known to give large rates for heavy neutralinos. Observational prospects thus seem promising.},
doi = {10.1103/PhysRevLett.95.241301},
journal = {Physical Review Letters},
number = 24,
volume = 95,
place = {United States},
year = {Fri Dec 09 00:00:00 EST 2005},
month = {Fri Dec 09 00:00:00 EST 2005}
}
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