OPTAB: Public code for generating gas opacity tables for radiation hydrodynamics simulations

¹ Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa 236-0001, Japan
e-mail: hirose.shigenobu@gmail.com
² Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg, Germany
³ Astronomical Institute, Graduate School of Science, Tohoku University, Aoba, Sendai 980-8578, Japan
⁴ Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871, Japan

Received: 14 April 2021
Accepted: 3 December 2021

Abstract

We have developed a public code, OPTAB, that outputs Rosseland, Planck, and two-temperature Planck mean gas opacity tables for radiation hydrodynamics simulations in astrophysics. The code is developed for modern high-performance computing, being written in Fortran 90 and using Message Passing Interface and Hierarchical Data Format, Version 5. The purpose of this work is to provide a platform on which users can generate opacity tables for their own research purposes. Therefore, the code has been designed so that a user can easily modify, change, or add opacity sources in addition to those already implemented, which include bremsstrahlung, photoionization, Rayleigh scattering, line absorption, and collision-induced absorption. In this paper, we provide details of the opacity calculations in our code and present validation tests to evaluate the performance of our code.