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Title: Optical Variability of Narrow-line and Broad-line Seyfert 1 Galaxies

Abstract

We studied the optical variability (OV) of a large sample of narrow-line Seyfert 1 (NLSy1) and broad-line Seyfert 1 (BLSy1) galaxies with z < 0.8 to investigate any differences in their OV properties. Using archival optical V -band light curves from the Catalina Real Time Transient Survey that span 5–9 years and modeling them using damped random walk, we estimated the amplitude of variability. We found that NLSy1 galaxies as a class show lower amplitude of variability than their broad-line counterparts. In the sample of both NLSy1 and BLSy1 galaxies, radio-loud sources are found to have higher variability amplitude than radio-quiet sources. Considering only sources that are detected in the X-ray band, NLSy1 galaxies are less optically variable than BLSy1 galaxies. The amplitude of variability in the sample of both NLSy1 and BLSy1 galaxies is found to be anti-correlated with Fe ii strength but correlated with the width of the H β line. The well-known anti-correlation of variability–luminosity and the variability–Eddington ratio is present in our data. Among the radio-loud sample, variability amplitude is found to be correlated with radio-loudness and radio-power, suggesting that jets also play an important role in the OV in radio-loud objects, in addition to themore » Eddington ratio, which is the main driving factor of OV in radio-quiet sources.« less

Authors:
;  [1]
  1. Indian Institute of Astrophysics, Block II, Koramangala, Bangalore-560034 (India)
Publication Date:
OSTI Identifier:
22663488
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 842; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; BALMER LINES; CORRELATIONS; GALAXIES; LUMINOSITY; RANDOMNESS; SIMULATION; SPECTRA; VISIBLE RADIATION; X RADIATION

Citation Formats

Rakshit, Suvendu, and Stalin, C. S., E-mail: suvenduat@gmail.com. Optical Variability of Narrow-line and Broad-line Seyfert 1 Galaxies. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA72F4.
Rakshit, Suvendu, & Stalin, C. S., E-mail: suvenduat@gmail.com. Optical Variability of Narrow-line and Broad-line Seyfert 1 Galaxies. United States. doi:10.3847/1538-4357/AA72F4.
Rakshit, Suvendu, and Stalin, C. S., E-mail: suvenduat@gmail.com. Tue . "Optical Variability of Narrow-line and Broad-line Seyfert 1 Galaxies". United States. doi:10.3847/1538-4357/AA72F4.
@article{osti_22663488,
title = {Optical Variability of Narrow-line and Broad-line Seyfert 1 Galaxies},
author = {Rakshit, Suvendu and Stalin, C. S., E-mail: suvenduat@gmail.com},
abstractNote = {We studied the optical variability (OV) of a large sample of narrow-line Seyfert 1 (NLSy1) and broad-line Seyfert 1 (BLSy1) galaxies with z < 0.8 to investigate any differences in their OV properties. Using archival optical V -band light curves from the Catalina Real Time Transient Survey that span 5–9 years and modeling them using damped random walk, we estimated the amplitude of variability. We found that NLSy1 galaxies as a class show lower amplitude of variability than their broad-line counterparts. In the sample of both NLSy1 and BLSy1 galaxies, radio-loud sources are found to have higher variability amplitude than radio-quiet sources. Considering only sources that are detected in the X-ray band, NLSy1 galaxies are less optically variable than BLSy1 galaxies. The amplitude of variability in the sample of both NLSy1 and BLSy1 galaxies is found to be anti-correlated with Fe ii strength but correlated with the width of the H β line. The well-known anti-correlation of variability–luminosity and the variability–Eddington ratio is present in our data. Among the radio-loud sample, variability amplitude is found to be correlated with radio-loudness and radio-power, suggesting that jets also play an important role in the OV in radio-loud objects, in addition to the Eddington ratio, which is the main driving factor of OV in radio-quiet sources.},
doi = {10.3847/1538-4357/AA72F4},
journal = {Astrophysical Journal},
number = 2,
volume = 842,
place = {United States},
year = {Tue Jun 20 00:00:00 EDT 2017},
month = {Tue Jun 20 00:00:00 EDT 2017}
}