2011-03-03

don't co-add your data!

Lang showed today that there is no sensible co-addition of imaging data that permits the detection of sources as well as estimating significance jointly in the not co-added images. The best formulation of this is to create not a co-add, but a significance map that maps out on the sky the likelihood of a source as a function of position. The combination of these significance maps is non trivial—it is not simple signal-to-noise-squared weighting of signal-to-noise maps—but it is tractable and no harder than most current co-adding schemes. Now we will sell this technology to any survey team in exchange for the fraction of observing time or operating cash we save them!

2 comments:

  1. This basic concept is actually already embedded in the heart of the DOLPHOT package for crowded field stellar photometry!

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  2. What model do you use for the source profile, and how do you integrate over its parameters?

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