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arXiv · 1705.05693

The Herschel/PACS Point Source Catalogue Explanatory Supplement

Abstract

The Herschel Space Observatory was the fourth cornerstone mission in the European Space Agency (ESA) science programme. It had excellent broad band imaging capabilities in the far-infrared (FIR) and sub-millimetre part of the electromagnetic spectrum. Although the spacecraft finished observing in 2013, it left a large legacy dataset that is far from having been fully explored and still has a great potential for new scientific discoveries. The PACS and SPIRE photometric cameras observed about 8% of the sky in six different wavebands. This document describes the Herschel/PACS Point Source Catalogue (HPPSC), a FIR catalogue based on the broad-band photometric observations of the PACS instrument with filters centred at 70, 100 and 160 microns. We analysed 14842 combined, Level 2.5/Level 3 Herschel/PACS photometric observations. The PACS photometer maps were generated by the JScanam task of the Herschel Interactive Processing Environment (HIPE) v13.0.0. Sources were identified with the HIPE implementation of SUSSEXtractor, and the flux densities obtained by aperture photometry. We found a total of 108 319 point sources that are considered to be reliable in the 70 micron maps, 131 322 at 100 micron and 251 392 point sources in the 160 micron maps. In addition, our quality control algorithm identified 546 587 candidate sources that were found to be extended and 7 185 160 features which did not pass the signal-to-noise and other criteria to be considered reliable sources. These sources were included in the Extended Source List and Rejected Source List of the HPPSC, respectively. The calculated completeness and photometric accuracy values are based on simulations, where artificial sources were injected into the observational timeline with well controlled flux density values. The actual completeness is a complex function of the source flux, photometric band and the background complexity.

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G. Marton, L. Calzoletti, A. M. Perez Garcia, C. Kiss, R. Paladini, B. Altieri, M. Sanchez Portal, M. Kidger, the Herschel Point Source Catalogue Working Group. 2017-05-16. The Herschel/PACS Point Source Catalogue Explanatory Supplement. https://arxiv.org/abs/1705.05693

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