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Title: Wavelet-based techniques for the gamma-ray sky

Abstract

Here, we demonstrate how the image analysis technique of wavelet decomposition can be applied to the gamma-ray sky to separate emission on different angular scales. New structures on scales that differ from the scales of the conventional astrophysical foreground and background uncertainties can be robustly extracted, allowing a model-independent characterization with no presumption of exact signal morphology. As a test case, we generate mock gamma-ray data to demonstrate our ability to extract extended signals without assuming a fixed spatial template. For some point source luminosity functions, our technique also allows us to differentiate a diffuse signal in gamma-rays from dark matter annihilation and extended gamma-ray point source populations in a data-driven way.

Authors:
 [1];  [2];  [3];  [4]
  1. SUNY Stony Brook, Stony Brook, NY (United States)
  2. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
  3. The Johns Hopkins Univ., Baltimore, MD (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
  4. Broad Institute, Cambridge, MA (United States); Princeton Univ., Princeton, NJ (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1341885
Report Number(s):
FERMILAB-PUB-15-504-T; YITP-SB-15-43; arXiv:1512.00012
Journal ID: ISSN 1475-7516; 1407425; TRN: US1701809
Grant/Contract Number:
AC02-07CH11359
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2016; Journal Issue: 07; Journal ID: ISSN 1475-7516
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; dark matter theory; gamma ray detectors

Citation Formats

McDermott, Samuel D., Fox, Patrick J., Cholis, Ilias, and Lee, Samuel K. Wavelet-based techniques for the gamma-ray sky. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/07/045.
McDermott, Samuel D., Fox, Patrick J., Cholis, Ilias, & Lee, Samuel K. Wavelet-based techniques for the gamma-ray sky. United States. doi:10.1088/1475-7516/2016/07/045.
McDermott, Samuel D., Fox, Patrick J., Cholis, Ilias, and Lee, Samuel K. Fri . "Wavelet-based techniques for the gamma-ray sky". United States. doi:10.1088/1475-7516/2016/07/045. https://www.osti.gov/servlets/purl/1341885.
@article{osti_1341885,
title = {Wavelet-based techniques for the gamma-ray sky},
author = {McDermott, Samuel D. and Fox, Patrick J. and Cholis, Ilias and Lee, Samuel K.},
abstractNote = {Here, we demonstrate how the image analysis technique of wavelet decomposition can be applied to the gamma-ray sky to separate emission on different angular scales. New structures on scales that differ from the scales of the conventional astrophysical foreground and background uncertainties can be robustly extracted, allowing a model-independent characterization with no presumption of exact signal morphology. As a test case, we generate mock gamma-ray data to demonstrate our ability to extract extended signals without assuming a fixed spatial template. For some point source luminosity functions, our technique also allows us to differentiate a diffuse signal in gamma-rays from dark matter annihilation and extended gamma-ray point source populations in a data-driven way.},
doi = {10.1088/1475-7516/2016/07/045},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 07,
volume = 2016,
place = {United States},
year = {Fri Jul 01 00:00:00 EDT 2016},
month = {Fri Jul 01 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
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