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

¹ Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternware 16, 14482 Potsdam, Germany
e-mail: christian.herenz@astro.su.se
² Department of Astronomy, Stockholm University, AlbaNova University Centre, 106 91 Stockholm, Sweden

Received: 9 August 2016
Accepted: 15 March 2017

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 Line Source Detection and Cataloguing (LSDCat). LSDCat uses a three-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 of processing 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.