STEPARSYN: A Bayesian code to infer stellar atmospheric parameters using spectral synthesis

Context. STEPARSYN is an automatic code written in Python 3.X designed to infer the stellar atmospheric parameters T-eff, log g, and [Fe/H] of FGKM-type stars following the spectral synthesis method. Aims. We present a description of the STEPARSYN code and test its performance against a sample of la...

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Detalles Bibliográficos
Autores: Tabernero, H. M., Gómez Marfil, Emilio, Montes Gutiérrez, David, González Hernández, J. I.
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/71676
Acceso en línea:https://hdl.handle.net/20.500.14352/71676
Access Level:acceso abierto
Palabra clave:52
To-limb variation
Radial-velocities
Spectroscopic parameters
Galah survey
M dwarfs
Stars
Planet
Metallicities
Abundance
Search
Astrofísica
Descripción
Sumario:Context. STEPARSYN is an automatic code written in Python 3.X designed to infer the stellar atmospheric parameters T-eff, log g, and [Fe/H] of FGKM-type stars following the spectral synthesis method. Aims. We present a description of the STEPARSYN code and test its performance against a sample of late-type stars that were observed with the HERMES spectrograph mounted at the 1.2-m Mercator Telescope. This sample contains 35 late-type targets with well-known stellar parameters determined independently from spectroscopy. The code is available to the astronomical community in a GitHub repository. Methods. STEPARSYN uses a Markov chain Monte Carlo sampler to explore the parameter space by comparing synthetic model spectra generated on the fly to the observations. The synthetic spectra are generated with an spectral emulator. Results. We computed T-eff, log g, and [Fe/H] for our sample stars and discussed the performance of the code. We calculated an internal scatter for these targets of -12 +/- 117 K in T-eff, 0.04 +/- 0.14 dex in log g, and 0.05 +/- 0.09 dex in [Fe/H]. In addition, we find that the log g values obtained with STEPARSYN are consistent with the trigonometric surface gravities to the 0.1 dex level. Finally, STEPARSYN can compute stellar parameters that are accurate down to 50 K, 0.1 dex, and 0.05 dex for T-eff, log g, and [Fe/H] for stars with v sin i <= 30 km s(-1).