International Journal of Astrophysics and Space Science

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Compact Steep-Spectrum Radio Sources and Ambient Medium Density

Received: 13 January 2015    Accepted: 06 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.

DOI 10.11648/j.ijass.20150301.11
Published in International Journal of Astrophysics and Space Science (Volume 3, Issue 1, February 2015)
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), 2024. Published by Science Publishing Group

Keywords

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

References
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Author Information
  • Department of Physics and Industrial physics, NnamdiAzikiwe University, Awka, Anambra State, Nigeria

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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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    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://download.sciencepg.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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