Physics Of Eclipsing Binaries. IX. Spectroscopic module

TL;DR

This paper introduces a spectroscopic module for Phoebe that models stellar spectra using synthetic spectra grids, enabling detailed analysis of stellar atmospheres in binary and multiple star systems.

Contribution

It presents a new spectroscopic module for Phoebe that interpolates synthetic spectra and models limb darkening, applicable to various stellar systems.

Findings

Module allows modeling of spectra in normalized or absolute units.

Approximates limb darkening with an analytical law.

Suitable for single, binary, or multiple star systems.

Abstract

Spectroscopic observations constrain the fundamental properties of stellar atmospheres, in particular, the effective temperature, the gravitational acceleration, or the metallicity. In this work, we describe the spectroscopic module for Phoebe, which allows for modelling of spectra, either normalized, or in absolute units (${\rm W}\,{\rm m}^{-2}\,{\rm m}^{-1}$). The module is based on extensive grids of synthetic spectra, taken from literature, which are interpolated and integrated over the surface. As an approximation, we assume that limb darkening is given by an analytical law, while other effects (e.g., eclipses) are treated self-consistently. Our approach is suitable for single stars, binaries, or multiples, and can be further extended to systems with pulsating components. This draft refers to a development version of Phoebe, available at https://github.com/miroslavbroz/phoebe2/tree/spectroscopy2 . It is not yet included in the official Phoebe repository!