Measuring the Balmer Jump and Effective Gravity in FGK Stars

TL;DR

This paper presents a spectroscopic method to accurately determine the effective gravity in FGK stars by analyzing the Balmer jump, overcoming limitations of photometric techniques across various metallicities and reddenings.

Contribution

It introduces a simple spectroscopic approach to measure log g in late-type stars using Balmer jump comparisons with synthetic spectra, improving accuracy over photometric methods.

Findings

Spectroscopic measurements of Balmer jump yield precise log g values.

Method effective across different metallicities and reddening conditions.

Provides a practical technique for stellar parameter determination.

Abstract

It is difficult to accurately measure the effective gravity (log g) in late-type stars using broadband (eg. UBV or SDSS) or intermediate-band (uvby) photometric systems, especially when the stars can cover a range of metallicities and reddenings. However, simple spectroscopic observational and data reduction techniques can yield accurate values for log g through comparison of the Balmer jumps of low-resolution spectra with recent grids of synthetic flux spectra.