Grain physics and rosseland mean opacities

Jason W. Ferguson, Amanda Heffner-Wong, Jonathan J. Penley, Travis S Barman, David R. Alexander

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Tables of mean opacities are often used to compute the transfer of radiation in a variety of astrophysical simula-tions, from stellar evolution models to protoplanetary disks. Often these tables, such as those in a recent paper by Ferguson and coworkers, are computed with a predetermined set of physical assumptions that may or may not be valid for a specific application. This paper explores the effects of several assumptions of grain physics on the Rosseland mean opacity in an oxygen-rich environment. We find that changing the distribution of grain sizes, either the power-law exponent or the shape of the distribution, has a marginal effect on the total mean opacity. We also explore the dif-ference in the mean opacity between solid homogenous grains and grains that are porous or conglomerations of several species. Changing the amount of grain opacity included in the mean by assuming a grain-to-gas ratio sig-nificantly affects the mean opacity, but in a predictable way.

Original languageEnglish (US)
Pages (from-to)261-266
Number of pages6
JournalAstrophysical Journal
Volume666
Issue number1 I
DOIs
StatePublished - 2007
Externally publishedYes

Fingerprint

opacity
physics
power law
grain size
oxygen
gas
protoplanetary disks
stellar evolution
distribution
effect
astrophysics
exponents
radiation
gases

Keywords

  • Astronomical data bases: miscellaneous
  • Dust, extinction
  • Equation of state
  • Methods: numerical

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Ferguson, J. W., Heffner-Wong, A., Penley, J. J., Barman, T. S., & Alexander, D. R. (2007). Grain physics and rosseland mean opacities. Astrophysical Journal, 666(1 I), 261-266. https://doi.org/10.1086/519783

Grain physics and rosseland mean opacities. / Ferguson, Jason W.; Heffner-Wong, Amanda; Penley, Jonathan J.; Barman, Travis S; Alexander, David R.

In: Astrophysical Journal, Vol. 666, No. 1 I, 2007, p. 261-266.

Research output: Contribution to journalArticle

Ferguson, JW, Heffner-Wong, A, Penley, JJ, Barman, TS & Alexander, DR 2007, 'Grain physics and rosseland mean opacities', Astrophysical Journal, vol. 666, no. 1 I, pp. 261-266. https://doi.org/10.1086/519783
Ferguson JW, Heffner-Wong A, Penley JJ, Barman TS, Alexander DR. Grain physics and rosseland mean opacities. Astrophysical Journal. 2007;666(1 I):261-266. https://doi.org/10.1086/519783
Ferguson, Jason W. ; Heffner-Wong, Amanda ; Penley, Jonathan J. ; Barman, Travis S ; Alexander, David R. / Grain physics and rosseland mean opacities. In: Astrophysical Journal. 2007 ; Vol. 666, No. 1 I. pp. 261-266.
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