Abstract
The variation of spectral index α 51.4 with luminosity (P 1.4) was investigated for Fanaroff and Riley type II galaxies and also for type I and type I/II galaxies. To reduce the effect of the redshift dependence of luminosity, samples which did not have widely different median redshifts were used and the data was binned into redshift ranges.
By a comparison of the median spectral indices in different redshift bins for FRII galaxies, no dependence of spectral index was formed on redshift. However, an increase in spectral index with increasing luminosity was found. The results for FRI and FRI/II galaxies were similar to those for the FRII galaxies.
References
Allington Smith, J. R.: 1982,Monthly Notices Roy. Astron. Soc. 199, 611.
Baars, J. W. M., Genzel, R., Pauliny Toth, I. I. K., and Witzel, A.: 1977,Astron. Astrophys. 61, 99.
Bridle, A. H., Kesteven, M. J. L., and Guindon, B.: 1972,Astrophys. Letters 11, 27.
Fanaroff, B. L. and Longair, M. S.: 1973,Monthly Notices Roy. Astron. Soc. 161, 393.
Fanaroff, B. L. and Longair, M. S.: 1974,Monthly Notices Roy. Astron. Soc. 167, 31p.
Gopal Krishna: 1988,Astron. Astrophys. 192, 37.
Katgert Merkelijn, J., Lari, C., and Padrielli, L.: 1980,Astron. Astrophys. Suppl. Ser. 40, 91.
Kellermann, K. I. and Pauliny Toth, I. I. K.: 1969,Astrophys. J. 155, L71.
Kuhr, H., Nauber, U., Pauliny Toth, I. I. K., and Witzel, A.: 1979, MPIfR preprint No. 55, Bonn.
Kuhr, H., Witzel, A., Pauliny Toth, I. I. K., and Nauber, U.: 1981,Astron. Astrophys. Suppl. 45, 367.
Laing, R. A. and Peacock, J. A.: 1980,Monthly Notices Roy. Astron. Soc. 190, 903.
Machalski, J. and Condon, J. J.: 1985,Astron. J. 90, 973.
Macklin, J. T.: 1982,Monthly Notices Roy. Astron. Soc. 199, 1119.
Peacock, J. A. and Wall, J. V.:Monthly Notices Roy. Astron. Soc. 194, 331.
Robertson, J. G.: 1973,Australian J. Phys. 26, 403.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Onuora, L.I. The variation of spectral index with luminosity for radio galaxies. Astrophys Space Sci 162, 349–352 (1989). https://doi.org/10.1007/BF00640750
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00640750