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Title: Limits on the radiative decay of sterile neutrino dark matter from the unresolved cosmic and soft x-ray backgrounds

Abstract

We present upper limits on line emission in the Cosmic X-ray background (CXB) that would be produced by decay of sterile neutrino dark matter. We employ the spectra of the unresolved component of the CXB in the Chandra Deep Fields North and South obtained with the Chandra CCD detector in the E=0.8-9 keV band. The expected decay flux comes from the dark matter on the lines of sight through the Milky Way galactic halo. Our constraints on the sterile neutrino decay rate are sensitive to the modeling of the Milky Way halo. The highest halo mass estimates provide a limit on the sterile neutrino mass of m{sub s}<2.9 keV in the Dodelson-Widrow production model, while the lowest halo mass estimates provide the conservative limit of m{sub s}<5.7 keV (2{sigma}). We also discuss constraints from a short observation of the softer (E<1 keV) X-ray background with a rocket-borne calorimeter by McCammon and collaborators.

Authors:
 [1];  [2];  [3];  [4];  [5];  [2];  [3]
  1. Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)
  2. (United States)
  3. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138 (United States)
  4. (Russian Federation)
  5. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
21020135
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.063511; (c) 2007 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; CHARGE-COUPLED DEVICES; COMPUTERIZED SIMULATION; COSMIC PHOTONS; KEV RANGE; LIMITING VALUES; MILKY WAY; NEUTRINOS; NONLUMINOUS MATTER; PARTICLE DECAY; RADIATIVE DECAY; REST MASS; SHOWER COUNTERS; SOFT X RADIATION

Citation Formats

Abazajian, Kevork N., Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Markevitch, Maxim, Space Research Institute, Russian Acad. Sci., Profsoyuznaya 84/32, Moscow 117997,, Koushiappas, Savvas M., ISR Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, and Hickox, Ryan C. Limits on the radiative decay of sterile neutrino dark matter from the unresolved cosmic and soft x-ray backgrounds. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.063511.
Abazajian, Kevork N., Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Markevitch, Maxim, Space Research Institute, Russian Acad. Sci., Profsoyuznaya 84/32, Moscow 117997,, Koushiappas, Savvas M., ISR Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, & Hickox, Ryan C. Limits on the radiative decay of sterile neutrino dark matter from the unresolved cosmic and soft x-ray backgrounds. United States. doi:10.1103/PHYSREVD.75.063511.
Abazajian, Kevork N., Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Markevitch, Maxim, Space Research Institute, Russian Acad. Sci., Profsoyuznaya 84/32, Moscow 117997,, Koushiappas, Savvas M., ISR Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, and Hickox, Ryan C. Thu . "Limits on the radiative decay of sterile neutrino dark matter from the unresolved cosmic and soft x-ray backgrounds". United States. doi:10.1103/PHYSREVD.75.063511.
@article{osti_21020135,
title = {Limits on the radiative decay of sterile neutrino dark matter from the unresolved cosmic and soft x-ray backgrounds},
author = {Abazajian, Kevork N. and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 and Markevitch, Maxim and Space Research Institute, Russian Acad. Sci., Profsoyuznaya 84/32, Moscow 117997, and Koushiappas, Savvas M. and ISR Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 and Hickox, Ryan C.},
abstractNote = {We present upper limits on line emission in the Cosmic X-ray background (CXB) that would be produced by decay of sterile neutrino dark matter. We employ the spectra of the unresolved component of the CXB in the Chandra Deep Fields North and South obtained with the Chandra CCD detector in the E=0.8-9 keV band. The expected decay flux comes from the dark matter on the lines of sight through the Milky Way galactic halo. Our constraints on the sterile neutrino decay rate are sensitive to the modeling of the Milky Way halo. The highest halo mass estimates provide a limit on the sterile neutrino mass of m{sub s}<2.9 keV in the Dodelson-Widrow production model, while the lowest halo mass estimates provide the conservative limit of m{sub s}<5.7 keV (2{sigma}). We also discuss constraints from a short observation of the softer (E<1 keV) X-ray background with a rocket-borne calorimeter by McCammon and collaborators.},
doi = {10.1103/PHYSREVD.75.063511},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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