Sources of the Radio Background Considered
Abstract
We investigate possible origins of the extragalactic radio background reported by the ARCADE 2 collaboration. The surface brightness of the background is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low surface brightness regions of radio sources, and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, we conclude that most of the radio background is produced by radio point sources that dominate at sub {mu}Jy fluxes. We show that a truly diffuse background produced by elections far from galaxies is ruled out because such energetic electrons would overproduce the observed X-ray/{gamma}-ray background through inverse Compton scattering of the other photon fields. Unrecognized flux from low surface brightness regions of extended radio sources, or moderate flux sources missed entirely by radio source count surveys, cannot explain the bulk of the observed background, but may contribute as much as 10%. We consider both radio supernovae and radio quiet quasars as candidate sources for the background, and show that both fail to produce it at the observedmore »
- Authors:
- Publication Date:
- Research Org.:
- SLAC National Accelerator Lab., Menlo Park, CA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 968533
- Report Number(s):
- SLAC-PUB-13714
Journal ID: ISSN 0035-8711; arXiv:0909.1997; TRN: US0904696
- DOE Contract Number:
- AC02-76SF00515
- Resource Type:
- Journal Article
- Journal Name:
- Mon.Not.Roy.Astron.Soc.409:1172,2010
- Additional Journal Information:
- Journal Name: Mon.Not.Roy.Astron.Soc.409:1172,2010; Journal ID: ISSN 0035-8711
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 43 PARTICLE ACCELERATORS; BRIGHTNESS; COMPTON EFFECT; GALAXIES; PHOTONS; POINT SOURCES; PRODUCTION; QUASARS; SUPERNOVAE; SYNCHROTRONS; TAIL ELECTRONS; Astrophysics,ASTRO
Citation Formats
Singal, J, /KIPAC, Menlo Park /Stanford U., Stawarz, L, /KIPAC, Menlo Park /Stanford U. /Jagiellonian U., Astron. Observ., Lawrence, A, /Edinburgh U., Inst. Astron. /KIPAC, Menlo Park /Stanford U., Petrosian, V, and /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept. Sources of the Radio Background Considered. United States: N. p., 2011.
Web. doi:10.1111/j.1365-2966.2010.17382.x.
Singal, J, /KIPAC, Menlo Park /Stanford U., Stawarz, L, /KIPAC, Menlo Park /Stanford U. /Jagiellonian U., Astron. Observ., Lawrence, A, /Edinburgh U., Inst. Astron. /KIPAC, Menlo Park /Stanford U., Petrosian, V, & /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept. Sources of the Radio Background Considered. United States. https://doi.org/10.1111/j.1365-2966.2010.17382.x
Singal, J, /KIPAC, Menlo Park /Stanford U., Stawarz, L, /KIPAC, Menlo Park /Stanford U. /Jagiellonian U., Astron. Observ., Lawrence, A, /Edinburgh U., Inst. Astron. /KIPAC, Menlo Park /Stanford U., Petrosian, V, and /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept. 2011.
"Sources of the Radio Background Considered". United States. https://doi.org/10.1111/j.1365-2966.2010.17382.x. https://www.osti.gov/servlets/purl/968533.
@article{osti_968533,
title = {Sources of the Radio Background Considered},
author = {Singal, J and /KIPAC, Menlo Park /Stanford U. and Stawarz, L and /KIPAC, Menlo Park /Stanford U. /Jagiellonian U., Astron. Observ. and Lawrence, A and /Edinburgh U., Inst. Astron. /KIPAC, Menlo Park /Stanford U. and Petrosian, V and /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept.},
abstractNote = {We investigate possible origins of the extragalactic radio background reported by the ARCADE 2 collaboration. The surface brightness of the background is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low surface brightness regions of radio sources, and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, we conclude that most of the radio background is produced by radio point sources that dominate at sub {mu}Jy fluxes. We show that a truly diffuse background produced by elections far from galaxies is ruled out because such energetic electrons would overproduce the observed X-ray/{gamma}-ray background through inverse Compton scattering of the other photon fields. Unrecognized flux from low surface brightness regions of extended radio sources, or moderate flux sources missed entirely by radio source count surveys, cannot explain the bulk of the observed background, but may contribute as much as 10%. We consider both radio supernovae and radio quiet quasars as candidate sources for the background, and show that both fail to produce it at the observed level because of insufficient number of objects and total flux, although radio quiet quasars contribute at the level of at least a few percent. We conclude that the most important population for production of the background is likely ordinary starforming galaxies above redshift 1 characterized by an evolving radio far-infrared correlation, which increases toward the radio loud with redshift.},
doi = {10.1111/j.1365-2966.2010.17382.x},
url = {https://www.osti.gov/biblio/968533},
journal = {Mon.Not.Roy.Astron.Soc.409:1172,2010},
issn = {0035-8711},
number = ,
volume = ,
place = {United States},
year = {Mon Aug 22 00:00:00 EDT 2011},
month = {Mon Aug 22 00:00:00 EDT 2011}
}