Long Term UV Continuum and Line Variability in NGC 1275

Authors

  • Bryan Rithesh Miranda Department on Physics, Bangalore University, Bengaluru, Karnataka, India, 560056
  • Vijayakumar H Doddamani Department on Physics, Bangalore University, Bengaluru, Karnataka, India, 560056
  • Vedavathi P Department on Physics, Bangalore University, Bengaluru, Karnataka, India, 560056

DOI:

https://doi.org/10.12723/mjs.56.4

Keywords:

Active Galactic Nuclei, active galaxies, continuum flux, emission line flux, Relative variability amplitudes, normalized excess variance, light curve

Abstract

In this paper, we present our results for the first time on long term emission-line and continuum variability studies using the International Ultraviolet Explorer’s final archive of UV spectroscopic data obtained in the wavelength region from 1150 Å to 3200 Å for NGC 1275, a dust dominated BL Lac characterized by the Rmax and  F-variance parameter. The UV continuum flux variability analysis presented in this paper covers more number of emission-line free continuum windows in the UV region centred at  1710 Å, 1800 Å, 2625 Å, 2875 Å & 3025 Å. We have obtained a higher value of Fvar  ~ 45 % at 1710 Å and a lower value of ~ 30 % at 1800 Å for the IUE's observational period of 1978 - 1989. The Lyα, C IV, C III] and Mg II emission lines have been observed as weaker line features on fewer occasions intermittently.

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Additional Files

Published

2021-01-01