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arXiv · 1905.05160

CHANG-ES XX. High Resolution Radio Continuum Images of Edge-on Galaxies and their AGNs -- Data Release 3

Judith Irwin·Theresa Wiegert·Alison Merritt·Marek Wezgowiec·Lucas Hunt·Alex Woodfinden·Yelena Stein·Ancor Damas-Segovia·Jiangtao Li·Q. Daniel Wang·Megan Johnson·Marita Krause·Ralf-Juergen Dettmar·Jisung Im·Philip Schmidt·Arpad Miskolczi·Timothy T. Braun·D. J. Saikia·Jayanne English·Mark L. A. Richardson
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Abstract

The CHANG-ES galaxy sample consists of 35 nearby edge-on galaxies that have been observed using the VLA at 1.6 GHz and 6.0 GHz. Here we present the 3rd data release of our sample, namely the B-configuration 1.6 GHz sample. In addition, we make available the {\it band-to-band} spectral index maps between 1.6 GHz and 6.0 GHz, the latter taken in the matching resolution C-configuration. The images can be downloaded from https://www.queensu.ca/changes. These are our highest resolution images ($\approx$ 3 arcsec) and we examine the possible presence of low luminosity active galactic nuclei in the sample as well as some in-disk structure. New features can be seen in the spectral index maps that are masked in the total intensity emission, including hidden spiral arms in NGC~3448 and two previously unknown radio lobes on either side of the nucleus of NGC~3628. Our AGN detection rate, using only radio criteria, is 55\% which we take as a lower limit because some weaker embedded AGNs are likely present which could be revealed at higher resolution. Archival XMM-Newton data were used to search for further fingerprints of the AGNs in the studied sample. In galaxy disks, discrete regions of flat spectral index are seen, likely due to a thermal emission fraction that is higher than the global average.

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Judith Irwin, Theresa Wiegert, Alison Merritt, Marek Wezgowiec, Lucas Hunt, Alex Woodfinden, Yelena Stein, Ancor Damas-Segovia, Jiangtao Li, Q. Daniel Wang, Megan Johnson, Marita Krause, Ralf-Juergen Dettmar, Jisung Im, Philip Schmidt, Arpad Miskolczi, Timothy T. Braun, D. J. Saikia, Jayanne English, Mark L. A. Richardson. 2019-05-08. CHANG-ES XX. High Resolution Radio Continuum Images of Edge-on Galaxies and their AGNs -- Data Release 3. https://doi.org/10.3847/1538-3881%2Fab25f6

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