A Search for Extragalactic Background Light Using the Dark Cloud L134
Abstract
CCD surface photometry at 0.65 micron and single-aperture photometry at 2.2 microns on the dark molecular cloud, L134, and on nearby blank sky, were carried out at levels of 0.001 and less than 0.0001 of the brightness of the night sky, respectively. Presumably because of the reflected Galactic light, the cloud appeared bright compared to the reference sky at both these wavelengths. Relative to blank fields, the darkest positions on the cloud had intensities of 1 x 10 to the -5th erg s/sq cm/s/sr at 0.65 micron and 4 x 10 to the -5th ergs/sq cm/s/sr at 2.2 microns. Since the magnitude of the reflected light is unknown, one cannot deduce the level of the extragalactic background light (EBL); however, either the EBL is on the order of or smaller than these values, or the reflected light and the EBL fortuitously cancel.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1986
- DOI:
- 10.1086/164574
- Bibcode:
- 1986ApJ...309...33B
- Keywords:
-
- Astronomical Photometry;
- Background Radiation;
- Cosmology;
- Extraterrestrial Radiation;
- Molecular Clouds;
- Infrared Photometry;
- Light (Visible Radiation);
- Astronomy;
- COSMOLOGY;
- PHOTOMETRY