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arXiv · 2202.08987

Multiwavelength analysis and the C IV λ1549 Å emission line behavior from 2008 to 2020 of the FSRQ B2 1633+382

Abstract

The flat-spectrum radio quasar B2 1633+382 (4C 38.41) has been monitored for several years and has presented correlated variability in multiple wavelengths. In this article, we are performing different analyses for multiple frequencies, from gamma-rays to radio, as well as, the C IV $λ$1549 Å emission line and the $λ$1350 Å continuum. Using the non-thermal dominance parameter, we separated the C IV and the continuum light curves for when the dominant source of continuum is the accretion disk or the jet. We found a correlation at a delay consistent with zero between the line and the continuum dominated by disk emission indicating a very small broad-line region (BLR). From the resulting delay between the 15 GHz and gamma-rays, we estimated the distance of the gamma-ray emission region from the jet apex to be $\sim$37 pc. The C IV flux decreases when the continuum and gamma-rays increase at some of the high activity periods. The C IV profile presents a larger variable component in its blue wing. The relation between the luminosities of C IV and the continuum does not completely follow the relation for a quasar sample. Our results lead us to propose an outflow of BLR material in the jet-flow direction, a gamma-ray production through magnetic reconnection for the flaring event of mid-2011, and that there is not enough BLR material close to the radio core to be easily ionized by the non-thermal continuum.

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Raúl Antonio Amaya-Almazán, Vahram Chavushyan, Víctor Manuel Patiño-Álvarez. 2022-02-24. Multiwavelength analysis and the C IV λ1549 Å emission line behavior from 2008 to 2020 of the FSRQ B2 1633+382. https://doi.org/10.3847/1538-4357%2Fac5741

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