David J. Frew, Ivan S. Bojicic, Quentin A. Parker, Mark J. Pierce, M. L. P. Gunawardhana, W. A. Reid
The AAO/UKST SuperCOSMOS H-alpha Survey (SHS) of the southern Galactic plane was, when completed in 2003, a powerful new addition to wide-field surveys. It has a combination of areal coverage, spatial resolution and flux sensitivity in a narrow imaging band which still marks it out today as an excellent resource for the astronomical community. The 233 separate fields are available online in digital form, with each field covering 25 square degrees. The SHS has been the motivation for equivalent surveys in the north, and new digital H-alpha surveys now beginning in the south such as VPHAS+. The SHS has been the foundation of many important follow-up discovery projects in the southern sky with the Macquarie/AAO/Strasbourg H-alpha (MASH) planetary nebula project being a particularly successful example. However, the full astrophysical potential of the SHS has been hampered by lack of a clear route to acceptable flux calibration from the base photographic data. We have determined the calibration factors for 170 separate SHS fields, and present a direct pathway to the measurement of integrated H-alpha fluxes and surface brightnesses for resolved nebulae detected in the SHS. We also include a catalogue of integrated H-alpha fluxes for 88 known PNe, and several HII regions and other objects measured from the SHS, and use these data to show that integrated fluxes, accurate to 0.1 -- 0.15 dex, can be generally obtained across these survey fields. For the remaining 63 fields, a mean calibration factor of 12.0 counts/px/rayleigh can be used, which will allow the determination of reasonable integrated fluxes accurate to better than 0.2 dex. We outline the procedures involved and the problems and limitations that need to be appreciated in achieving such flux measurements. This paper forms a handy reference source that will significantly increase the scientific utility of the SHS.
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http://arxiv.org/abs/1303.4555
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