The Gothard Observatory Synthetic Stellar Photometry Database

¹ ELTE Eötvös Loránd University, Gothard Astrophysical Observatory, Szent Imre H. u. 112., Szombathely 9700, Hungary
² MTA-ELTE Lendület “Momentum” Milky Way Research Group, Szent Imre H. u. 112., Szombathely 9700, Hungary
³ HUN-REN-ELTE Exoplanet Research Group, Szent Imre H. u. 112., Szombathely 9700, Hungary
⁴ HUN-REN CSFK, Konkoly Observatory, Konkoly Thege Miklós út 15-17, Budapest 1121, Hungary
⁵ HUN-REN Stellar Astrophysics Research Group, Szegedi út, Kt. 766, Baja 6500, Hungary

^★ Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 14 October 2025
Accepted: 17 December 2025

Abstract

Context. To determine stellar luminosities and radii, it is necessary to know the total bolometric fluxes emitted by stars - or equivalently their bolometric corrections (BCs) - as accurately as possible.

Aims. The aim of this paper is to present and describe a new database of synthetic stellar magnitudes and BCs for 752 filters from 78 ground- and space-based instruments calculated using the most recent version of the BOSZ synthetic stellar spectral library.

Methods. From the entire grid of BOSZ theoretical spectra, our synthetic magnitudes in the Vega magnitude system were determined using the corresponding species Python routines.

Results. The database spans effective temperatures from 2800 to 16 000 K, log g from −0.5 to 5.5, metallicities from −2.5 to 0.75, [α/M] from −0.25 to 0.5, [C/M] from −0.75 to 0.5, and reddening up to A_V = 3.1 mag. Using high-resolution (R = 50 000) synthetic spectra allowed us to precisely track the effects of abundances on stellar BCs and luminosities.

Conclusions. By applying the new BCs to 192 000 APOGEE stars, we calculated luminosities and demonstrated that neglecting carbon can introduce up to ±0.2% errors in luminosity. The new Gothard Observatory Synthetic Stellar Photometry Database may enable more accurate fundamental parameter determinations for large stellar samples using a vast amount of past, present, and upcoming surveys, such as Gaia, LSST, and the Roman Space Telescope.