CHANG-ES XXVII: A Radio/X-ray Catalogue of Compact Sources in and around Edge-on Galaxies

TL;DR

This paper presents comprehensive radio and X-ray source catalogues for 35 edge-on galaxies, identifying nuclear sources, potential active galactic nuclei, and a possible colliding wind binary, providing valuable data for galaxy and stellar studies.

Contribution

It provides the first combined radio and X-ray catalogues for these galaxies, including new nuclear source identifications and a candidate colliding wind binary, enhancing multi-wavelength galaxy analysis.

Findings

Detected 2507 radio sources at 1.6 GHz and 1413 at 6.0 GHz.

Identified three new low-luminosity active galactic nuclei candidates.

Discovered a potential foreground colliding wind binary system.

Abstract

We present catalogues of discrete, compact radio sources in and around the discs of 35 edge-on galaxies in the Continuum Halos in Nearby Galaxies -- an EVLA Survey (CHANG-ES). The sources were extracted using the PyBDSF program at both 1.6 GHz (L-band) and 6.0 GHz (C-band) from matching resolution ($\approx$ 3 arcsec) data. We also present catalogues of X-ray sources from Chandra data sets for 27 of the galaxies. The sources at the two radio frequency bands were positionally cross-correlated with each other, and the result cross-correlated with the X-ray sources. All catalogues are included for download with this paper. We detect a total of 2507 sources at L-band and 1413 sources at C-band. Seventy-five sources have been successfully cross-correlated in both radio bands plus X-ray. Three new nuclear sources are candidates for Low Luminosity Active Galactic Nuclei in NGC~3877, NGC~4192, and NGC~5792; the one in NGC~3877 also appears to be variable. We also find new nuclear sources in two companion galaxies: NGC~4435 (companion to NGC~4438) and NGC~4298 (companion to NGC~4302). We have also discovered what appears to be a foreground double-star; each star has X-ray emission and there is radio emission at both L-band and C-band in between them. This could be a colliding wind binary system. Suggestions for follow-up studies are offered.