A Robotic Wide-Angle Hα Survey of the Southern Sky
Abstract
We have completed a robotic wide-angle imaging survey of the southern sky (δ=+15deg to -90°) at 656.3 nm wavelength, the Hα emission line of hydrogen. Each image of the resulting Southern Hα Sky Survey Atlas (SHASSA) covers an area of the sky 13° square at an angular resolution of approximately 0.8‧ and reaches a sensitivity level of 2 R (1.2×10-17 ergs cm-2 s-1 arcsec-2) pixel-1, corresponding to an emission measure of 4 cm-6 pc and to a brightness temperature for microwave free-free emission of 12 μK at 30 GHz. Smoothing over several pixels allows features as faint as 0.5 R to be detected.
- Publication:
-
Publications of the Astronomical Society of the Pacific
- Pub Date:
- November 2001
- DOI:
- 10.1086/323969
- arXiv:
- arXiv:astro-ph/0108518
- Bibcode:
- 2001PASP..113.1326G
- Keywords:
-
- Cosmology: Cosmic Microwave Background;
- ISM: H II Regions;
- Instrumentation: Miscellaneous;
- ISM: Structure;
- Surveys;
- Techniques: Image Processing;
- Astrophysics
- E-Print:
- LATEX, 33 pages, 15 figures. Accepted for publication in PASP, 113, November 2001. Further information at http://amundsen.swarthmore.edu/SHASSA/