On the Extent of the Existence of Broad Line Region in Seyfert Galaxies
American Journal of Astronomy and Astrophysics
Volume 7, Issue 2, June 2019, Pages: 33-38
Received: Jul. 29, 2019; Accepted: Sep. 21, 2019; Published: Oct. 9, 2019
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Oyor David Ifeanyichukwu, Department of Science Laboratory Technology, Akanu Ibiam Federal Polytechnic, Afikpo, Nigeria
Ogwo Jemima Ngozi, Department of Physics, Abia State University, Uturu, Nigeria
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We present statistical results from a very large sample of Seyfert galaxies (217,272 galaxies) obtained from SDSS DR10 (Sloan Digital Sky Survey Data Release 10). From their observed parameters which includes; flux of hydrogen alpha (Hα), luminosity distance and velocity dispersion, we computed other relevant parameters such as; bolometric luminosity, black hole mass and mass accretion rate, which enabled us classify these Seyfert galaxies into Seyfert 1s (188,486 galaxies) and Seyfert 2s (28,786 galaxies). Analyses on these computed parameters revealed that Seyfert 2 galaxies were less luminous, more massive and accrete less matter than the Seyfert 1 galaxies. Further analysis on Seyfert 2s based on their mass accretion rate led to their classification into hidden broad line region (HBLR) Seyfert 2s (12,988 galaxies) and non-hidden broad line region (non-HBLR) Seyfert 2s (15,798 galaxies) which shows that, the HBLR S2s accrete more matter than the non-HBLR S2s. All the results obtained suggest that the bolometric luminosity alone is not sufficient in determining the extent of the existence of the BLR in Seyfert 2 galaxies rather the mass accretion rate should be taking into consideration in determining the appearance and disappearance of the BLR.
Galaxies, Seyfert, Accretion Rate, Bolometric Luminosity and Broad Line Region
To cite this article
Oyor David Ifeanyichukwu, Ogwo Jemima Ngozi, On the Extent of the Existence of Broad Line Region in Seyfert Galaxies, American Journal of Astronomy and Astrophysics. Vol. 7, No. 2, 2019, pp. 33-38. doi: 10.11648/j.ajaa.20190702.12
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