On the Extent of the Existence of Broad Line Region in Seyfert Galaxies

Oyor David Ifeanyichukwu; Ogwo Jemima Ngozi

doi:doi:10.11648/j.ajaa.20190702.12

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On the Extent of the Existence of Broad Line Region in Seyfert Galaxies

Oyor David Ifeanyichukwu, Ogwo Jemima Ngozi

Published in American Journal of Astronomy and Astrophysics (Volume 7, Issue 2)

Received: 29 July 2019 Accepted: 21 September 2019 Published: 9 October 2019

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Abstract

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.

Published in	American Journal of Astronomy and Astrophysics (Volume 7, Issue 2)
DOI	10.11648/j.ajaa.20190702.12
Page(s)	33-38
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Galaxies, Seyfert, Accretion Rate, Bolometric Luminosity and Broad Line Region

References

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Oyor David Ifeanyichukwu, Ogwo Jemima Ngozi. (2019). On the Extent of the Existence of Broad Line Region in Seyfert Galaxies. American Journal of Astronomy and Astrophysics, 7(2), 33-38. https://doi.org/10.11648/j.ajaa.20190702.12

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ACS Style

Oyor David Ifeanyichukwu; Ogwo Jemima Ngozi. On the Extent of the Existence of Broad Line Region in Seyfert Galaxies. Am. J. Astron. Astrophys. 2019, 7(2), 33-38. doi: 10.11648/j.ajaa.20190702.12

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AMA Style

Oyor David Ifeanyichukwu, Ogwo Jemima Ngozi. On the Extent of the Existence of Broad Line Region in Seyfert Galaxies. Am J Astron Astrophys. 2019;7(2):33-38. doi: 10.11648/j.ajaa.20190702.12

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@article{10.11648/j.ajaa.20190702.12,
  author = {Oyor David Ifeanyichukwu and Ogwo Jemima Ngozi},
  title = {On the Extent of the Existence of Broad Line Region in Seyfert Galaxies},
  journal = {American Journal of Astronomy and Astrophysics},
  volume = {7},
  number = {2},
  pages = {33-38},
  doi = {10.11648/j.ajaa.20190702.12},
  url = {https://doi.org/10.11648/j.ajaa.20190702.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajaa.20190702.12},
  abstract = {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.},
 year = {2019}
}

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TY  - JOUR
T1  - On the Extent of the Existence of Broad Line Region in Seyfert Galaxies
AU  - Oyor David Ifeanyichukwu
AU  - Ogwo Jemima Ngozi
Y1  - 2019/10/09
PY  - 2019
N1  - https://doi.org/10.11648/j.ajaa.20190702.12
DO  - 10.11648/j.ajaa.20190702.12
T2  - American Journal of Astronomy and Astrophysics
JF  - American Journal of Astronomy and Astrophysics
JO  - American Journal of Astronomy and Astrophysics
SP  - 33
EP  - 38
PB  - Science Publishing Group
SN  - 2376-4686
UR  - https://doi.org/10.11648/j.ajaa.20190702.12
AB  - 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.
VL  - 7
IS  - 2
ER  -

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Author Information

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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APA Style

Oyor David Ifeanyichukwu, Ogwo Jemima Ngozi. (2019). On the Extent of the Existence of Broad Line Region in Seyfert Galaxies. American Journal of Astronomy and Astrophysics, 7(2), 33-38. https://doi.org/10.11648/j.ajaa.20190702.12

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ACS Style

Oyor David Ifeanyichukwu; Ogwo Jemima Ngozi. On the Extent of the Existence of Broad Line Region in Seyfert Galaxies. Am. J. Astron. Astrophys. 2019, 7(2), 33-38. doi: 10.11648/j.ajaa.20190702.12

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AMA Style

Oyor David Ifeanyichukwu, Ogwo Jemima Ngozi. On the Extent of the Existence of Broad Line Region in Seyfert Galaxies. Am J Astron Astrophys. 2019;7(2):33-38. doi: 10.11648/j.ajaa.20190702.12

Copy | Download

@article{10.11648/j.ajaa.20190702.12,
  author = {Oyor David Ifeanyichukwu and Ogwo Jemima Ngozi},
  title = {On the Extent of the Existence of Broad Line Region in Seyfert Galaxies},
  journal = {American Journal of Astronomy and Astrophysics},
  volume = {7},
  number = {2},
  pages = {33-38},
  doi = {10.11648/j.ajaa.20190702.12},
  url = {https://doi.org/10.11648/j.ajaa.20190702.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajaa.20190702.12},
  abstract = {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.},
 year = {2019}
}

Copy | Download

TY  - JOUR
T1  - On the Extent of the Existence of Broad Line Region in Seyfert Galaxies
AU  - Oyor David Ifeanyichukwu
AU  - Ogwo Jemima Ngozi
Y1  - 2019/10/09
PY  - 2019
N1  - https://doi.org/10.11648/j.ajaa.20190702.12
DO  - 10.11648/j.ajaa.20190702.12
T2  - American Journal of Astronomy and Astrophysics
JF  - American Journal of Astronomy and Astrophysics
JO  - American Journal of Astronomy and Astrophysics
SP  - 33
EP  - 38
PB  - Science Publishing Group
SN  - 2376-4686
UR  - https://doi.org/10.11648/j.ajaa.20190702.12
AB  - 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.
VL  - 7
IS  - 2
ER  -

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