Hydra II: Characterisation of Aegean, Caesar, ProFound, PyBDSF, and Selavy source finders

Abstract

We present a comparison between the performance of a selection of source finders using a new software tool called Hydra. The companion paper, Paper~I, introduced the Hydra tool and demonstrated its performance using simulated data. Here we apply Hydra to assess the performance of different source finders by analysing real observational data taken from the Evolutionary Map of the Universe (EMU) Pilot Survey. EMU is a wide-field radio continuum survey whose primary goal is to make a deep ($20\mu$Jy/beam RMS noise), intermediate angular resolution ($15^{\prime \prime }$), 1\,GHz survey of the entire sky south of $+30^{\circ }$ declination, and expecting to detect and catalogue up to 40 million sources. With the main EMU survey expected to begin in 2022 it is highly desirable to understand the performance of radio image source finder software and to identify an approach that optimises source detection capabilities. Hydra has been developed to refine this process, as well as to deliver a range of metrics and source finding data products from multiple source finders. We present the performance of the five source finders tested here in terms of their completeness and reliability statistics, their flux density and source size measurements, and an exploration of case studies to highlight finder-specific limitations.

arXiv commentPaper accepted for publication in PASA

References in corpus (21)

• Astropy: A Community Python Package for Astronomy
• The GMRT 150 MHz All-sky Radio Survey: First Alternative Data Release TGSS ADR1
• SUMSS: A Wide-Field Radio Imaging Survey of the Southern Sky. II. The Source Catalogue
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue
• The Last of FIRST: The Final Catalog and Source Identifications
• Point Source Extraction with MOPEX
• The Molonglo Galactic Plane Survey (MGPS-2): Compact Source Catalogue
• Compact continuum source-finding for next generation radio surveys
• A Quick Look at the $3$GHz Radio Sky I. Source Statistics from the Very Large Array Sky Survey
• Deep ATLAS radio observations of the CDFS-SWIRE field
• ProFound: Source Extraction and Application to Modern Survey Data
• Source finding in the era of the SKA (precursors): Aegean 2.0
• A new source detection algorithm using FDR
• Duchamp: a 3D source finder for spectral-line data
• Source-finding for the Australian Square Kilometre Array Pathfinder
• Extragalactic Radio Continuum Surveys and the Transformation of Radio Astronomy
• DeepSource: Point Source Detection using Deep Learning
• Radio Source Extraction with ProFound
• The Allen Telescope Array Twenty-centimeter Survey -- A 700-Square-Degree, Multi-Epoch Radio Dataset -- II: Individual Epoch Transient Statistics
• SCORPIO: A deep survey of Radio Emission from the stellar life-cycle
• Automated detection of extended sources in radio maps: progress from the SCORPIO survey

Cited by in corpus (2)

• The LOFAR Two-Metre Sky Survey (LoTSS): VI. Optical identifications for the second data release
• Simulating images of radio galaxies with diffusion models