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arXiv · 1405.0715

The Peculiar Radio-Loud Narrow Line Seyfert 1 Galaxy 1H 0323+342

Vaidehi S. Paliya·S. Sahayanathan·M. L. Parker·A. C. Fabian·C. S. Stalin·Ayesha Anjum·S. B. Pandey
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Abstract

We present a multi-wavelength study of the radio-loud narrow line Seyfert 1 galaxy (NLSy1), 1H 0323+342, detected by Fermi Gamma Ray Space Telescope. Multi-band light curves show many orphan X-ray and optical flares having no corresponding {\gamma}-ray counterparts. Such anomalous variability behavior can be due to different locations of the emission region from the central source. During a large flare, {\gamma}-ray flux doubling time scale as small as $\sim$ 3 hours is noticed. We built spectral energy distribution (SED) during different activity states and modeled them using an one-zone leptonic model. The shape of the optical/UV component of the SEDs is dominated by accretion disk emission in all the activity states. In the X-ray band, significant thermal emission from the hot corona is inferred during quiescent and first flaring states, however, during subsequent flares, non-thermal jet component dominates. The {\gamma}-ray emission in all the states can be well explained by inverse-Compton scattering of accretion disk photons reprocessed by the broad line region. The source showed violent intra-night optical variability, coinciding with one of the high {\gamma}-ray activity states. An analysis of the overall X-ray spectrum fitted with an absorbed power-law plus relativistic reflection component hints for the presence of Fe K-{\alpha} line and returns a high black hole spin value of a=0.96 $\pm$ 0.14. We argue that 1H 0323+342 possesses dual characteristics, akin to flat spectrum radio quasars (FSRQs) as well as radio-quiet NLSy1s, though at a low jet power regime compared to powerful FSRQs.

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Vaidehi S. Paliya, S. Sahayanathan, M. L. Parker, A. C. Fabian, C. S. Stalin, Ayesha Anjum, S. B. Pandey. 2014-05-04. The Peculiar Radio-Loud Narrow Line Seyfert 1 Galaxy 1H 0323+342. https://doi.org/10.1088/0004-637x/789/2/143

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