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arXiv · 1309.0642

Using THELI pipeline in order to reduce Abell 226 multi-band optical images

R. Joveini·S. Sotoudeh·A. Roozrokh·M. Taheri
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Abstract

In this paper we review THELI (Erben & Schrimer, 2005), an image processing pipeline developed to reduce multi-pointing optical images taken by mosaic CCD cameras. This pipeline works on raw images by removing several instrumental contaminations, implementing photometric calibration and astrometric alignment, and constructing a deep co-added mosaic image complemented by a weight map. We demonstrate the procedure of reducing NGC3923 images from raw data to the final results. We also demonstrate the quality of our data reduction strategy using mag-count and mag-error in mag plots. Emphasis is mainly placed on photometric calibration which is of great interest to us due to our scientific case. Based on the cross-association of the extracted catalogue against a reference catalogue of stellar magnitudes, zero-point calibration is performed. Our data reduction strategy and the method employed for cross-correlating large catalogues is also presented.

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R. Joveini, S. Sotoudeh, A. Roozrokh, M. Taheri. 2013-09-03. Using THELI pipeline in order to reduce Abell 226 multi-band optical images. https://arxiv.org/abs/1309.0642

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