Further correction to the STARFORGE methods paper: Planck-mean dust opacities

TL;DR

This paper updates the Planck-mean dust opacity model used in STARFORGE simulations to improve accuracy at low radiation temperatures and clarifies the roles of dust and radiation temperatures in setting dust opacity.

Contribution

It provides an improved calculation of dust opacities as functions of dust and radiation temperatures, with updated code and formulas for broader applicability.

Findings

Enhanced dust opacity model for low radiation temperatures

Clarification of dust and radiation temperature roles

Provision of code and formulas for practical use

Abstract

The model for the Planck-mean dust opacity $\kappa_{P}$ given in Appendix C of the STARFORGE simulations methods paper does not extrapolate well to low radiation temperature $T_{\rm rad}$, so we provide an updated calculation suitable for general use. We also clarify the role of the dust and radiation temperatures in setting the dust opacity, and provide code and calculations of the Planck- and Rosseland- mean dust opacity as a function of both the dust temperature $T_{\rm d}$ and the radiation temperature $T_{\rm rad}$.