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arXiv · 1709.07202

The radio structure of the peculiar narrow-line Seyfert 1 galaxy candidate J1100+4421

K. É. Gabányi·S. Frey·Z. Paragi·E. Järvelä·T. Morokuma·T. An·M. Tanaka·I. Tar
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Abstract

Narrow-line Seyfert 1 galaxies (NLS1) are an intriguing subclass of active galactic nuclei. Their observed properties indicate low central black hole mass and high accretion rate. The extremely radio-loud NLS1 sources often show relativistic beaming and are usually regarded as younger counterparts of blazars. Recently, the object SDSS J110006.07+442144.3 was reported as a candidate NLS1 source. The characteristics of its dramatic optical flare indicated its jet-related origin. The spectral energy distribution of the object was similar to that of the gamma-ray detected radio-loud NLS1, PMN J0948+0022. Our high-resolution European Very Long Baseline Interferometry Network observations at 1.7 and 5 GHz revealed a compact core feature with a brightness temperature of >~ 10^(10) K. Using the lowest brightness temperature value and assuming a moderate Lorentz factor of ~9 the jet viewing angle is <~ 26 deg. Archival Very Large Array data show a large-scale radio structure with a projected linear size of ~150 kpc reminiscent of double-sided morphology.

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K. É. Gabányi, S. Frey, Z. Paragi, E. Järvelä, T. Morokuma, T. An, M. Tanaka, I. Tar. 2017-09-21. The radio structure of the peculiar narrow-line Seyfert 1 galaxy candidate J1100+4421. https://doi.org/10.1093/mnras%2Fstx2449

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