Hot-Star Models from 100 to 10,000 Angstroms

TL;DR

This paper discusses the development and application of theoretical spectral libraries for hot, massive stars across a wide wavelength range, crucial for population synthesis models like Starburst99.

Contribution

It presents new theoretical spectral libraries for hot stars from 100 to 10,000 Angstroms, addressing challenges posed by their rarity and complex radiation properties.

Findings

Libraries successfully model UV and X-ray spectra of hot stars

Comparison shows good agreement with observational data

Libraries improve the accuracy of population synthesis predictions

Abstract

The spectral libraries of hot, massive stars which are implemented in the population synthesis code Starburst99 are discussed. Hot stars pose particular challenges for generating libraries. They are rare, they have an intense radiation field and strong stellar winds, and a luminosity bias towards ultraviolet wavelengths. These properties require the utilization of theoretical libraries. Starburst99 uses static non-LTE models at 0.3 A resolution in the optical, spherically extended, expanding models at 0.4 A resolution in the satellite-ultraviolet, and blanketed, low-resolution radiation-hydrodynamical models in the extreme ultraviolet down to X-rays. I review the main features of each library, compare them to observations, and discuss their link with stellar evolution models.