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arXiv · 1805.03039

The First VLBI Detection of a Spiral DRAGN Core

Minnie Y. Mao·Jay M. Blanchard·Frazer Owen·Loránt O. Sjouwerman·Vikram Singh·Anna Scaife·Zsolt Paragi·Ray P. Norris·Emmanuel Momjian·Gia Johnson·Ian Browne
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Abstract

The existence of spiral DRAGNs challenges standard galaxy formation theories. We present the first observation of 0313$-$192, the archetypal spiral DRAGN, at VLBI resolutions. Spiral DRAGNs are Double Radio Sources Associated with Galactic Nuclei (DRAGNs) that are hosted by spiral galaxies. 0313$-$192 is an edge-on spiral galaxy that appears to host a 360 kpc double-lobed radio source. The core of this galaxy is clearly detected at L, S, and X-bands using the VLBA, signifying an ongoing active nucleus in the galaxy. This rules out the possibility that the spiral DRAGN is merely a chance alignment. The radio core has L$_{1.4\,GHz} \sim 3.0 \times 10^{23}$W Hz$^{-1}$. Radio components are detected to the South-West of the core, but there are no detections of a counterjet. Assuming a symmetric, relativistic jet, we estimate an upper limit to the inclination angle of $\theta \lesssim 72$ degrees. The VLBI-detected radio jet components are extremely well-aligned with the larger-scale radio source suggesting little to no jet disruption or interaction with the ISM of the host galaxy.

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Minnie Y. Mao, Jay M. Blanchard, Frazer Owen, Loránt O. Sjouwerman, Vikram Singh, Anna Scaife, Zsolt Paragi, Ray P. Norris, Emmanuel Momjian, Gia Johnson, Ian Browne. 2018-05-08. The First VLBI Detection of a Spiral DRAGN Core. https://doi.org/10.1093/mnrasl/sly081

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