Compact Steep-Spectrum Radio Sources and Ambient Medium Density

Ezeugo Jeremiah Chukwuemerie

doi:doi:10.11648/j.ijass.20150301.11

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Compact Steep-Spectrum Radio Sources and Ambient Medium Density

Ezeugo Jeremiah Chukwuemerie

Published in International Journal of Astrophysics and Space Science (Volume 3, Issue 1)

Received: 13 January 2015 Accepted: 6 February 2015 Published: 16 February 2015

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Abstract

Analytical and statistical methods,with some plausible assumptions, have been used in this work to show presence of dense medium around compact steep-spectrum sources in our sample. This is done by carrying out regression analyses using our estimated jet’s internal densities (n_j ) and some other source parameters for possible deductions. Results indicate that n_j-D and n_j-n_e data (where D and n_e are respectively, observed source linear size and ambient medium density) show strong correlations and yield power-law relations of the forms, n_j~D^(-3.54±0.02) and n_j~n_e^(1.68±0.08). A comparison with obtained theoretical relations suggestively indicates presence of dense gases around these sources. In addition, a simple linear regression analysis of ν_p-n_j data shows that jet’s particles may be responsible (in addition to the ambient gases) for the observed spectral turnover characteristic of compact steep spectrum sources.

Published in	International Journal of Astrophysics and Space Science (Volume 3, Issue 1)
DOI	10.11648/j.ijass.20150301.11
Page(s)	1-6
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), 2015. Published by Science Publishing Group

Keywords

Spectral Turnover, Steep-Spectrum, Astrophysical Jet, Ambient Density, Active Galaxies

References

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Ezeugo Jeremiah Chukwuemerie. (2015). Compact Steep-Spectrum Radio Sources and Ambient Medium Density. International Journal of Astrophysics and Space Science, 3(1), 1-6. https://doi.org/10.11648/j.ijass.20150301.11

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ACS Style

Ezeugo Jeremiah Chukwuemerie. Compact Steep-Spectrum Radio Sources and Ambient Medium Density. Int. J. Astrophys. Space Sci. 2015, 3(1), 1-6. doi: 10.11648/j.ijass.20150301.11

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AMA Style

Ezeugo Jeremiah Chukwuemerie. Compact Steep-Spectrum Radio Sources and Ambient Medium Density. Int J Astrophys Space Sci. 2015;3(1):1-6. doi: 10.11648/j.ijass.20150301.11

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@article{10.11648/j.ijass.20150301.11,
  author = {Ezeugo Jeremiah Chukwuemerie},
  title = {Compact Steep-Spectrum Radio Sources and Ambient Medium Density},
  journal = {International Journal of Astrophysics and Space Science},
  volume = {3},
  number = {1},
  pages = {1-6},
  doi = {10.11648/j.ijass.20150301.11},
  url = {https://doi.org/10.11648/j.ijass.20150301.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijass.20150301.11},
  abstract = {Analytical and statistical methods,with some plausible assumptions, have been used in this work to show presence of dense medium around compact steep-spectrum sources in our sample. This is done by carrying out regression analyses using our estimated jet’s internal densities (n_j ) and some other source parameters for possible deductions. Results indicate that n_j-D and n_j-n_e data (where D and n_e are respectively, observed source linear size and ambient medium density) show strong correlations and yield power-law relations of the forms, n_j~D^(-3.54±0.02) and n_j~n_e^(1.68±0.08). A comparison with obtained theoretical relations suggestively indicates presence of dense gases around these sources. In addition, a simple linear regression analysis of ν_p-n_j data shows that jet’s particles may be responsible (in addition to the ambient gases) for the observed spectral turnover characteristic of compact steep spectrum sources.},
 year = {2015}
}

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TY  - JOUR
T1  - Compact Steep-Spectrum Radio Sources and Ambient Medium Density
AU  - Ezeugo Jeremiah Chukwuemerie
Y1  - 2015/02/16
PY  - 2015
N1  - https://doi.org/10.11648/j.ijass.20150301.11
DO  - 10.11648/j.ijass.20150301.11
T2  - International Journal of Astrophysics and Space Science
JF  - International Journal of Astrophysics and Space Science
JO  - International Journal of Astrophysics and Space Science
SP  - 1
EP  - 6
PB  - Science Publishing Group
SN  - 2376-7022
UR  - https://doi.org/10.11648/j.ijass.20150301.11
AB  - Analytical and statistical methods,with some plausible assumptions, have been used in this work to show presence of dense medium around compact steep-spectrum sources in our sample. This is done by carrying out regression analyses using our estimated jet’s internal densities (n_j ) and some other source parameters for possible deductions. Results indicate that n_j-D and n_j-n_e data (where D and n_e are respectively, observed source linear size and ambient medium density) show strong correlations and yield power-law relations of the forms, n_j~D^(-3.54±0.02) and n_j~n_e^(1.68±0.08). A comparison with obtained theoretical relations suggestively indicates presence of dense gases around these sources. In addition, a simple linear regression analysis of ν_p-n_j data shows that jet’s particles may be responsible (in addition to the ambient gases) for the observed spectral turnover characteristic of compact steep spectrum sources.
VL  - 3
IS  - 1
ER  -

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Author Information

Ezeugo Jeremiah Chukwuemerie

Department of Physics and Industrial physics, NnamdiAzikiwe University, Awka, Anambra State, Nigeria

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APA Style

Ezeugo Jeremiah Chukwuemerie. (2015). Compact Steep-Spectrum Radio Sources and Ambient Medium Density. International Journal of Astrophysics and Space Science, 3(1), 1-6. https://doi.org/10.11648/j.ijass.20150301.11

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ACS Style

Ezeugo Jeremiah Chukwuemerie. Compact Steep-Spectrum Radio Sources and Ambient Medium Density. Int. J. Astrophys. Space Sci. 2015, 3(1), 1-6. doi: 10.11648/j.ijass.20150301.11

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AMA Style

Ezeugo Jeremiah Chukwuemerie. Compact Steep-Spectrum Radio Sources and Ambient Medium Density. Int J Astrophys Space Sci. 2015;3(1):1-6. doi: 10.11648/j.ijass.20150301.11

Copy | Download

@article{10.11648/j.ijass.20150301.11,
  author = {Ezeugo Jeremiah Chukwuemerie},
  title = {Compact Steep-Spectrum Radio Sources and Ambient Medium Density},
  journal = {International Journal of Astrophysics and Space Science},
  volume = {3},
  number = {1},
  pages = {1-6},
  doi = {10.11648/j.ijass.20150301.11},
  url = {https://doi.org/10.11648/j.ijass.20150301.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijass.20150301.11},
  abstract = {Analytical and statistical methods,with some plausible assumptions, have been used in this work to show presence of dense medium around compact steep-spectrum sources in our sample. This is done by carrying out regression analyses using our estimated jet’s internal densities (n_j ) and some other source parameters for possible deductions. Results indicate that n_j-D and n_j-n_e data (where D and n_e are respectively, observed source linear size and ambient medium density) show strong correlations and yield power-law relations of the forms, n_j~D^(-3.54±0.02) and n_j~n_e^(1.68±0.08). A comparison with obtained theoretical relations suggestively indicates presence of dense gases around these sources. In addition, a simple linear regression analysis of ν_p-n_j data shows that jet’s particles may be responsible (in addition to the ambient gases) for the observed spectral turnover characteristic of compact steep spectrum sources.},
 year = {2015}
}

Copy | Download

TY  - JOUR
T1  - Compact Steep-Spectrum Radio Sources and Ambient Medium Density
AU  - Ezeugo Jeremiah Chukwuemerie
Y1  - 2015/02/16
PY  - 2015
N1  - https://doi.org/10.11648/j.ijass.20150301.11
DO  - 10.11648/j.ijass.20150301.11
T2  - International Journal of Astrophysics and Space Science
JF  - International Journal of Astrophysics and Space Science
JO  - International Journal of Astrophysics and Space Science
SP  - 1
EP  - 6
PB  - Science Publishing Group
SN  - 2376-7022
UR  - https://doi.org/10.11648/j.ijass.20150301.11
AB  - Analytical and statistical methods,with some plausible assumptions, have been used in this work to show presence of dense medium around compact steep-spectrum sources in our sample. This is done by carrying out regression analyses using our estimated jet’s internal densities (n_j ) and some other source parameters for possible deductions. Results indicate that n_j-D and n_j-n_e data (where D and n_e are respectively, observed source linear size and ambient medium density) show strong correlations and yield power-law relations of the forms, n_j~D^(-3.54±0.02) and n_j~n_e^(1.68±0.08). A comparison with obtained theoretical relations suggestively indicates presence of dense gases around these sources. In addition, a simple linear regression analysis of ν_p-n_j data shows that jet’s particles may be responsible (in addition to the ambient gases) for the observed spectral turnover characteristic of compact steep spectrum sources.
VL  - 3
IS  - 1
ER  -

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