Monitoring of active galactic nuclei. V. The Seyfert 1 galaxy Markarian 279

G. M. Stirpe

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arXiv · astro-ph/9311001

Monitoring of active galactic nuclei. V. The Seyfert 1 galaxy Markarian 279

G. M. Stirpe

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Abstract

We report on the Lovers of Active Galaxies' (LAG) monitoring of the Seyfert 1 galaxy Markarian 279 from January to June 1990. The source, which was in a very bright state, gradually weakened after the first month of monitoring: the H-Alpha and H-Beta flux decreased by 20% and 35% respectively, and the continuum under H-Alpha by 30%. The luminosity-weighted radius of the broad line region (BLR), as derived from the cross-correlation function, is of the order of 10 light days. This result is very uncertain because the features in the light curves are very shallow, but it is unlikely that the radius of the BLR is more than 1 light month. The profile variations of H-Alpha confirm that the prevailing motions are not radial. The data of the present campaign and those obtained in previous years, when the source was in a much weaker state, show that the red asymmetry of the Balmer lines correlates positively with the broad line flux. This new effect is briefly discussed.

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G. M. Stirpe. 1993-11-01. Monitoring of active galactic nuclei. V. The Seyfert 1 galaxy Markarian 279. https://arxiv.org/abs/astro-ph/9311001

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