A standard stellar library for evolutionary synthesis: I. Calibration of theoretical spectra

TL;DR

This paper introduces a hybrid library of synthetic stellar spectra calibrated to match empirical color-temperature relations, enhancing the accuracy of synthetic photometry across various stellar parameters.

Contribution

It presents a comprehensive, calibrated library of synthetic stellar spectra based on multiple model atmosphere grids, improving the realism and applicability of synthetic photometry.

Findings

The library covers extensive ranges in stellar parameters.

Calibration ensures synthetic colors match empirical data.

Flux spectra are provided with uniform wavelength resolution.

Abstract

A comprehensive hybrid library of synthetic stellar spectra based on three original grids of model atmosphere spectra by Kurucz (1995), Fluks et al. (1994), and Bessell et al. (1989, 1991) is presented. The combined library is intended for multiple-purpose synthetic photometry applications and is constructed in order (i) to cover the largest possible ranges in Teff, log g, and [M/H]), (ii) to provide flux spectra with useful resolution on the uniform grid of wavelengths, and (iii) to provide realistic synthetic broad-band colors for the largest possible parameter and wavelength ranges. For each value of the effective temperature and for each wavelength, we calculate the correction function that must be applied to a (theoretical) solar-abundance model flux spectrum which yields synthetic UBVRIJHKL colors matching the (empirical) color-temperature calibrations derived from observations. The calibration algorithm is designed to preserve the original differential grid properties implied by metallicity and/or luminosity changes in the new library. The corresponding color calibration is described in some detail.