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

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 γ-ray counterparts. Such anomalous variability behavior can be due to different locations of the emission region from the central source. During a large flare, γ-ray flux doubling time scale as small as ∼ 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 γ-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 γ-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-α line and returns a high black hole spin value of a=0.96 ± 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.

FERMIMONITORING OF RADIO-LOUD NARROW-LINE SEYFERT 1 GALAXIES

“…The primary reason for this contrast is the fact that 1H 0323+342 was in quiescence for most of the first four years of Fermi operation and could not produce enough photon statistics to study short timescale variability. These findings are similar to what was recently reported by Paliya et al (2014). The highest flux in the sixhour binned light curve is measured as (7.80 ± 1.43) × 10 −6 --ph cm s 2 1…”

“…A maximum γ-ray flux of (5.11 ± 0.62) × 10 −7 --ph cm s 2 1 is observed in the bin centered at MJD 56,537 when a GeV flare was detected by Fermi-LAT (Carpenter & Ojha 2013;Paliya et al 2014). The five-year averaged TS value of this source is ∼723, which corresponds to ∼27σ detection.…”

“…Instead, the LP model seems to describe the data better. From the SED modeling of 1H 0323+342 and PMN J0948+0022, Abdo et al (2009d) constrained their γ-ray emission region to be well inside the BLR (see also Foschini et al 2012;Paliya et al 2014). In such a scenario, the presence of the curvature in the γ-ray spectrum of these two sources can be explained on the basis of the KN effect.…”

Properties of flat-spectrum radio-loud narrow-line Seyfert 1 galaxies

“…It is interesting to compare with radio-quiet Seyferts, where a correlation between 2-10 keV flux and the spectral index was found, indicating a steepening of the spectral shape as the flux Ghisellini et al ( , 2010 and Tavecchio et al (2010); BLS1s and RQNLS1s are from Grupe et al (2010). increases (Markowitz et al 2003). Some interesting episodes were described in the case of J0324+3410 by Foschini et al (2009, and Tibolla et al (2013): the source has generally a soft spectral index, typical of NLS1s, but sometimes -as the jet became active -the X-ray spectrum displays a break at a 2-3 keV and a hard tail appears (see also Paliya et al 2014). Similar behaviour has been observed in another RLNLS1, PKS 0558−504 9 , where ASCA observed a hardening of the spectral index during an outburst, changing from ∼ 1.2 to ∼ 0.9 (Wang et al 2001).…”

“…-J0324+3410: log P rad = 42.8, log P kin = 44.3 (averaged over one year, Abdo et al 2009c), and log P rad = 41.29-41.74, log P kin = 44.06-45.14 (different states over five years monitoring, Paliya et al 2014). -J0849+5108: log P rad = 45.6 (peak during an outburst), log P kin = 45.3( 10 ) (D'Ammando et al 2012).…”