1 November 2001 Source detection for the ISOCAM parallel survey
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In the so-called parallel mode, ISOCAM, the mid-infrared camera on board ESA's Infrared Space Observatory (ISO), continued to observe while other instruments were prime, thus providing a widespread high-sensitivity survey of the sky. The currently exploitable data set was taken during 7000 hours of observations and consists of over 37000 pointings. The source extraction from these images is a challenging task due to the following difficulties: * the small number of pixels per image (32*32), resulting into a highly under-sampled Point Spread Function * the varying sky area --- from flat background to highly structured or confused * the varying and a priori unknown instrumental noise and the highly varying duration of each pointing * the high number of spurious sources due to restricted glitch-rejection for observations with few readouts * the lack of redundant pointings for the majority of cases The algorithm developed to solve these problems consists of a combination of three detection methods: * sextractor, using various thresholds and convolution files * multi-resolution detection * flux- and position determination of detected sources via modified point-source fitting * heuristic criteria to classify the sources into point- and extended sources
© (2001) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Stephan Ott, Stephan Ott, Jean-Luc Starck, Jean-Luc Starck, N. Schartel, N. Schartel, Ralf Siebenmorgen, Ralf Siebenmorgen, T. Vo, T. Vo, H. Aussel, H. Aussel, Etienne Bertin, Etienne Bertin, "Source detection for the ISOCAM parallel survey", Proc. SPIE 4477, Astronomical Data Analysis, (1 November 2001); doi: 10.1117/12.447186; https://doi.org/10.1117/12.447186

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