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Register a new userThe First VLBI Detection of a Spiral DRAGN Core
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Minnie Y. Mao
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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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