| Abstract : | Narrow Line Seyfert 1 (NLSy1) galaxies are a special class of active
galactic nuclei (AGN) identified by Osterbrock and Pogge about four decades
ago. They are classified based on the presence of narrow H_beta emission
line with the full width at half maximum < 2000 km/sec, strong FeII emission
and weak OIII emission line. The study on NLSy1 galaxies is now restricted to
low redshift (z < 0.8), because, definition requires the presence of H_beta
emission line which is redshifted outside the spectral coverage of
major ground based spectroscopic surveys available today. In the year
2021, Rakshit et al. have arrived at a sample of z > 0.8 NLSy1 candidates
treating the MgII line at 2800 Angstroms as a proxy for the
H_beta emission line. We have carried out a comparative analysis of the long
term optical and infrared variability characteristics of the high redshift
sample of NLSy1 galaxies vis-a-vis broad line Seyfert 1 (BLSy1) galaxies. The
control sample of BLSy1 galaxies were selected such that they match in the
optical g-band brightness, redshift and black hole mass to the sample of NLSy1
galaxies. In the optical band, BLSy1 galaxies are found to display a marginal
increase in variability compared to NLSy1 galaxies. We also investigated the
correlation of optical variability with radio-loudness, relativistic jet power
and accretion rate of the sample. Details of the results will be discussed. |
