Vol. 20 No. 1 (2021): Mapana Journal of Sciences
Research Articles

Long Term UV Continuum and Line Variability in NGC 1275

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  • Bryan Rithesh Miranda,
  • Vijayakumar H Doddamani,
  • Vedavathi P
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

Published 2021-08-28

Keywords

  • Active Galactic Nuclei,
  • active galaxies,
  • continuum flux,
  • emission line flux,
  • Relative variability amplitudes,
  • normalized excess variance,
  • light curve
    • ...More
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Copyright (c) 2021

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

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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