文章基本信息

标题：CHANG-ES. XX. High-resolution Radio Continuum Images of Edge-on Galaxies and Their AGNs: Data Release 3
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作者：Judith Irwin ; Theresa Wiegert ; Alison Merritt 等
期刊名称：The Astronomical journal
印刷版ISSN：0004-6256
电子版ISSN：1538-3881
出版年度：2019
卷号：158
期号：1
页码：1-22
DOI：10.3847/1538-3881/ab25f6
语种：English
出版社：American Institute of Physics
摘要：The CHANG-ES galaxy sample consists of 35 nearby edge-on galaxies that have been observed using the VLA at 1.6 and 6.0 GHz. Here we present the third data release of our sample, namely, the B configuration 1.6 GHz sample. In addition, we make available the band-to-band spectral index maps between 1.6 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 (≈3″), and we examine the possible presence of low-luminosity active galactic nuclei (AGNs) 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 that 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.
关键词：radio continuum: galaxies;surveys