Detalles de publicación
PP 026119
SPAMMS: 3D spectroscopic modelling of stellar surfaces. II. Implementation of Kurucz and TLUSTY model atmospheres
(1) Instituto de Astrofísica de Canarias, c/ Vía Láctea, s/n, E-38205 La Laguna, Tenerife, Spain
(2) Departamento de Astrofísica, Universidad de La Laguna, E-38206 La Laguna, Tenerife, Spain
(3) Institute of Astronomy, KU Leuven, Celestijnlaan 200D, 3001 Leuven, Belgium
(4) Leuven Gravity Institute, KU Leuven, Celestijnenlaan 200D, box 2415, 3001 Leuven, Belgium
Context. Accurate modeling of stellar spectra is essential to derive the physical properties of stars. However, traditional model atmospheres often oversimplify key phenomena that break spherical symmetry — such as deformations due to rotation or multiplicity. The Spectroscopic PAtch Model for Massive Stars (SPAMMS) addresses these limitations by explicitly accounting for surface distortions, resulting in more realistic spectra for deformed stars. Yet, SPAMMS has been limited by the spectral types covered by its model atmosphere grids.
Aims. We aim to extend the parameter space of the stellar atmosphere grids available to the SPAMMS framework. By expanding the coverage of effective temperatures, surface gravities and metallicities, we enable the synthesis of spectra across a broader range of spectral types.
Methods. We computed specific intensities, I(λ,μ), for 101 emergent angles using PRISMAS (Pipeline of Radiative Intensity Synthesis for Meshed Atmospheric Surfaces). Built upon synple, PRISMAS employed pre-computed LTE and non-LTE model atmospheres, including two ATLAS9-Kurucz grids and the TLUSTY-based OSTAR2002 and BSTAR2006 models.
Results. The computed intensity grids span effective temperatures from 3500 to 55000K, and surface gravities between 0.0 and 5.0dex — covering the entire spectral range from O- to K-type stars. These grids also incorporate multiple metallicities (0–30Z☉) and microturbulent velocities (1, 3, 5, 10kms⁻¹), enabling detailed modeling of stars across diverse evolutionary stages. The spectral coverage extends from 3000 to 9000Å, spanning both the ultraviolet and optical regimes with a sampling of Δλ = 0.01Å. As a proof of concept, we used the new intensity grids to model with SPAMMS (i) a rapidly rotating B-type star, and (ii) an eclipsing Algol-type binary.
Conclusions. The implementation of LTE-Kurucz and NLTE-TLUSTY model atmospheres has significantly expanded the parameter space accessible to SPAMMS. The code can now generate realistic synthetic spectra for a wide range of stellar types and geometries, including non-spherical and multiple systems. Therefore, by explicitly modelling three-dimensional surface effects, SPAMMS reproduces key observational signatures across a broad range of stellar masses and effective temperatures — from O- to K-type stars.
Aims. We aim to extend the parameter space of the stellar atmosphere grids available to the SPAMMS framework. By expanding the coverage of effective temperatures, surface gravities and metallicities, we enable the synthesis of spectra across a broader range of spectral types.
Methods. We computed specific intensities, I(λ,μ), for 101 emergent angles using PRISMAS (Pipeline of Radiative Intensity Synthesis for Meshed Atmospheric Surfaces). Built upon synple, PRISMAS employed pre-computed LTE and non-LTE model atmospheres, including two ATLAS9-Kurucz grids and the TLUSTY-based OSTAR2002 and BSTAR2006 models.
Results. The computed intensity grids span effective temperatures from 3500 to 55000K, and surface gravities between 0.0 and 5.0dex — covering the entire spectral range from O- to K-type stars. These grids also incorporate multiple metallicities (0–30Z☉) and microturbulent velocities (1, 3, 5, 10kms⁻¹), enabling detailed modeling of stars across diverse evolutionary stages. The spectral coverage extends from 3000 to 9000Å, spanning both the ultraviolet and optical regimes with a sampling of Δλ = 0.01Å. As a proof of concept, we used the new intensity grids to model with SPAMMS (i) a rapidly rotating B-type star, and (ii) an eclipsing Algol-type binary.
Conclusions. The implementation of LTE-Kurucz and NLTE-TLUSTY model atmospheres has significantly expanded the parameter space accessible to SPAMMS. The code can now generate realistic synthetic spectra for a wide range of stellar types and geometries, including non-spherical and multiple systems. Therefore, by explicitly modelling three-dimensional surface effects, SPAMMS reproduces key observational signatures across a broad range of stellar masses and effective temperatures — from O- to K-type stars.