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arXiv · 1703.05166

LSDCat: Detection and cataloguing of emission-line sources in integral-field spectroscopy datacubes

Edmund Christian Herenz·Lutz Wisotzki
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Abstract

We present a robust, efficient, and user-friendly algorithm for detecting faint emission-line sources in large integral-field spectroscopic datacubes together with the public release of the software package LSDCat (Line Source Detection and Cataloguing). LSDCat uses a 3-dimensional matched filter approach, combined with thresholding in signal-to-noise, to build a catalogue of individual line detections. In a second pass, the detected lines are grouped into distinct objects, and positions, spatial extents, and fluxes of the detected lines are determined. LSDCat requires only a small number of input parameters, and we provide guidelines for choosing appropriate values. The software is coded in Python and capable to process very large datacubes in a short time. We verify the implementation with a source insertion and recovery experiment utilising a real datacube taken with the MUSE instrument at the ESO Very Large Telescope.

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Edmund Christian Herenz, Lutz Wisotzki. 2017-03-15. LSDCat: Detection and cataloguing of emission-line sources in integral-field spectroscopy datacubes. https://doi.org/10.1051/0004-6361/201629507

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