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The Opacity Project and the Iron Project

Published online by Cambridge University Press:  12 April 2016

Anil K. Pradhan
Anil K. Pradhan*
Affiliation:
Department of Astronomy, The Ohio State University, 174 West 18th Avenue, Columbus, OH 43210, USA

Abstract

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Systematic and large-scale calculation of accurate plasma opacities and atomic data by the Opacity Project and the Iron Project has applications in many areas of astrophysics. Analysis of EUVE observations using monochromatic opacities of elements calculated by the Opacity Project is described. Theoretical methods and atomic calculations are discussed briefly. Recent work related to ionization balance, photoionization and recombination, and the modeling of plasmas in local thermodynamic equilibrium (LTE) and non-LTE are discussed. New calculations for the important iron ions, under the Iron Project, are also described and their relevance to the more extensive non-LTE calculations is pointed out. The comprehensive radiative and collisional data sets from the Opacity and the Iron Projects should be applicable to a large number of sources in the EUV and other wavelength regions.

Type
XIII. Plasma Diagnostics
Information
International Astronomical Union Colloquium , Volume 152: Astrophysics in the Extreme Ultraviolet , 1996 , pp. 569 - 576
Copyright
Copyright © Kluwer 1996

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