Abstract
The purpose of this paper is to present a numerical technique to directly compute the Chandrasekhar'sH (μ)-function for anisotropic scattering in terms of the roots of the characteristic equations as well as the quadrature points of a certain degreen employed to approximate the definite integral involved in the basic equation. The principal feature of the algorithm proposed here is a compact computer code to enumerate n C m combinations ofn distinct integers {1,...,n} takenm at a time. With these quantities available, the coefficients of the polynomial equation of the characteristics equation can be readily computed for any given characteristic function, so that a standard technique such as the Laguerre method can be applied to find all the roots.
It is shown that the results obtained for some representativeH(μ)-functions using the present technique with relatively low-order formula (e.g.,n=7) are sufficiently accurate for all practical purposes.
Similar content being viewed by others
References
Abhyankar, K. D. and Fymat, A. L.: 1969,J. Quant. Spectr. Rad. Trans. 9, 1563.
Barman, S. K.: 1989,J. Quant. Spectr. Rad. Trans. 41, 221.
Bond, G. R. and Siewert, C.: 1971,Astrophys. J. 164, 97.
Bosma, P. B. and de Rooij, W. A.: 1983,Astron. Astrophys. 126, 283.
Carlstedt, J. L. and Mullikin, T. W.: 1966,Astrophys. J. Suppl. 12, 449.
Chandrasekhar, S.: 1960,Radiative Transfer, Dover Publ., Inc., New York, 393 pp.
Domke, H.: 1988,J. Quant. Spectr. Rad. Trans. 39, 283.
Ganapol, B.: 1990,J. Quant. Spectr. Rad. Trans. 44, 289.
Ivanov, V. V.: 1973,Transfer of Radiation in Spectral Lines, NBS Special Publication 385, US Government Printing Office, Washington, D.C., pp. 461.
Kourganoff, V.: 1963,Basic Methods in Transfer Problems (with I. W. Busbridge), Dover Publ. Inc., New York, 281 pp.
Kriese, J. T. and Siewert, C. E.: 1971,Astrophys. J. 164, 389.
Kuščer, I. and McCormick, N. J.: 1974, in J. G. Kuriyan (ed.),UCLA Int. Conf. Radiat. Remote Probing Atmos., Western Periodicals Co., North Hollywood, Ca, p. 196.
Lenoble, J.: 1985,Radiative Transfer in Scattering and Absorbing Atmospheres, A. Deepak Publishing, Hampton, Va., 300 pp.
Press, W. H., Flannery, B., Teukolsky, S. A., and Vetterling, W. T.: 1986,Numerical Recipes, Cambridge University Press, Cambridge, 818 pp.
Rutily, B. and Bergeat, J.: 1985,J. Quant. Spectr. Rad. Trans. 33, 373.
Rutily, B. and Bergeat, J.: 1987,J. Quant. Spectr. Rad. Trans. 38, 47.
Sobolev, V. V.: 1975,Light Scattering in Planetary Atmospheres (translated by W. M. Irvine), Pergamon Press, New York, 256 pp.
Stamnes, K., Tsay, S., Wiscombe, W., and Jayaweera, K.: 1988,Applied Optics 27, 2502.
Van de Hulst, H. C.: 1980,Multiple Light Scattering: Tables, Formulas, and Applications, Academic Press, New York, Vols. 1 and 2, 739 pp.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kawabata, K., Satoh, T. & Ueno, S. A direct numerical approach to the Chandrasekhar'sH-functions for arbitrary characteristic functions. Astrophys Space Sci 182, 249–260 (1991). https://doi.org/10.1007/BF00645005
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00645005