Astronomy and Astrophysics – Astrophysics
Scientific paper
May 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008a%26a...482.1053k&link_type=abstract
Astronomy and Astrophysics, Volume 482, Issue 3, 2008, pp.1053-1067
Astronomy and Astrophysics
Astrophysics
4
Techniques: Image Processing, Methods: Data Analysis, Techniques: Photometric, Galaxies: Fundamental Parameters
Scientific paper
Aims: We describe a new technique for measuring accurate galaxy colours from images taken under different seeing conditions. Methods: The method involves two ingredients. First we define the Gaussian-aperture-and-PSF flux, which is the Gaussian-weighted flux a galaxy would have if it were observed with a Gaussian PSF. This theoretical aperture flux is independent of the PSF or pixel scale that the galaxy was observed with. Second we develop a procedure for measuring such a “GaaP” flux from observed, pixellated images. This involves modelling source and PSF as a superposition of orthogonal shapelets. A correction scheme is also described that approximately corrects for any residuals to the shapelet expansions. Results: A series of tests on simulated images shows that it is possible with this method to reduce systematic errors in the matched-aperture fluxes to the level of one percent, which makes it useful for deriving photometric redshifts from large imaging surveys.
No associations
LandOfFree
GaaP: PSF- and aperture-matched photometry using shapelets does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with GaaP: PSF- and aperture-matched photometry using shapelets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and GaaP: PSF- and aperture-matched photometry using shapelets will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1393484