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A Robotic Wide-Angle H-Alpha Survey of the Southern Sky

J. E. Gaustad·P. R. McCullough·W. Rosing·D. Van Buren
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Abstract

We have completed a robotic wide-angle imaging survey of the southern sky (declination less than +15 degrees) at 656.3 nm wavelength, the H-alpha emission line of hydrogen. Each image of the resulting Southern H-Alpha Sky Survey Atlas (SHASSA) covers an area of the sky 13 degrees square at an angular resolution of approximately 0.8 arcminute, and reaches a sensitivity level of 2 rayleigh (1.2 x 10^-17 erg cm^-2 s^-1 arcsec^-2) per pixel, corresponding to an emission measure of 4 cm^-6 pc, and to a brightness temperature for microwave free-free emission of 12 microkelvins at 30 GHz. Smoothing over several pixels allows features as faint as 0.5 rayleigh to be detected.

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J. E. Gaustad, P. R. McCullough, W. Rosing, D. Van Buren. 2001-08-31. A Robotic Wide-Angle H-Alpha Survey of the Southern Sky. https://doi.org/10.1086/323969

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