SPAMMS: 3D spectroscopic modelling of stellar surfaces. II. Implementation of Kurucz and TLUSTY model atmospheres

Abstract

Context. Accurate stellar spectra are essential to derive stellar properties. Traditional model atmospheres often oversimplify phenomena that break spherical symmetry, such as rotational deformation or multiplicity. The Spectroscopic PAtch Model for Massive Stars (SPAMMS) accounts for these effects, but its applicability has been limited by the spectral types covered by its model atmosphere grids. Aims. We aim to extend the parameter space of the model atmosphere grids available to SPAMMS, enabling spectral synthesis across a broader range of stellar types. Methods. We computed specific intensities, $I\left(\lambda ,\mu \right)$, for $101$ emergent angles using PRISMAS (Pipeline of Radiative Intensity Synthesis for Meshed Atmospheric Surfaces), and pre-computed LTE and non-LTE atmospheres from two ATLAS9-Kurucz grids and the TLUSTY-based OSTAR2002 and BSTAR2006 models. Results. The intensity grids cover effective temperatures from $3500$ to $55000\mathrm{K}$ and surface gravities from $0.0$ to $5.0\mathrm{dex}$, spanning O- to K-type stars. They include metallicities from $0$ to $30{\mathrm{Z}}_{\odot }$ and microturbulent velocities of $1$, $3$, $5$, and $10\mathrm{km}{\mathrm{s}}^{-1}$. The spectral range extends from $3000$ to $9000\mathring{\mathrm{A}}$ with $\Delta \lambda =0.01\mathring{\mathrm{A}}$. As a proof of concept, we modelled with SPAMMS a rapidly rotating B-type star and an eclipsing Algol-type binary. Conclusions. The new LTE-Kurucz and NLTE-TLUSTY grids substantially expand the parameter space accessible to SPAMMS. The code can now generate synthetic spectra for a broader range of stellar types and geometries, including rapidly rotating and multiple systems -- providing a more comprehensive framework for modelling non-spherical stellar surfaces.

Accepted for publication in A&A; 12 pages (+3 appendix pages), 7 figures (+3 appendix figures)