Back to Search
Start Over
An Anomalous Component of Galactic Emission
- Source :
- Scopus-Elsevier
- Publication Year :
- 1997
- Publisher :
- American Astronomical Society, 1997.
-
Abstract
- We present results from microwave background observations at the Owens Valley Radio Observatory. These observations, at 14.5 and 32 GHz, are designed to detect intrinsic anisotropy on scales of 7'. After point source removal, we detect significant emission with temperature spectral index beta ~ -2 towards the North Celestial Pole (NCP). Comparison of our data with the IRAS 100 micron map of the same fields reveals a strong correlation between this emission and the infrared dust emission. From the lack of detectable H-alpha emission, we conclude that the signals are consistent either with flat-spectrum synchrotron radiation, or with free-free emission from T_e ~ 10^6 K gas, probably associated with a large HI feature known as the NCP Loop. Assuming beta = -2.2, our data indicate a conversion T_f/I_(100 micron) = 0.075*nu(GHz)^-2.2 K/(MJy/sr). The detection of such a component suggests that we should be cautious in any assumptions made regarding foregrounds when designing experiments to map the microwave background radiation.<br />6 pages, Latex, 3 Postscript figures, uses aas2pp4.sty
- Subjects :
- Physics
Spectral index
Point source
Infrared
Astrophysics::High Energy Astrophysical Phenomena
Astrophysics (astro-ph)
Cosmic microwave background
FOS: Physical sciences
Synchrotron radiation
Astronomy and Astrophysics
Owens Valley Radio Observatory
Astrophysics::Cosmology and Extragalactic Astrophysics
Astrophysics
Celestial pole
Space and Planetary Science
Beta (plasma physics)
Astrophysics::Galaxy Astrophysics
Subjects
Details
- ISSN :
- 0004637X
- Volume :
- 486
- Database :
- OpenAIRE
- Journal :
- The Astrophysical Journal
- Accession number :
- edsair.doi.dedup.....bc9d35da63f1f07bf5a1db6e1a6548e9
- Full Text :
- https://doi.org/10.1086/310823