Misclassified B stars in the Kepler field

TL;DR

This study identifies and corrects misclassifications of B stars in the Kepler field, revealing inaccuracies in the Kepler Input Catalog and providing refined stellar parameters through spectroscopic analysis.

Contribution

It uncovers four misclassified B stars in Kepler data and demonstrates improved parameter estimation using LAMOST spectra.

Findings

Confirmed systematic errors in KIC stellar parameters.

Identified four misclassified B stars previously labeled as A-type variables.

Provided detailed spectroscopic and frequency analysis of these stars.

Abstract

Stellar fundamental parameters are important in the asteroseismic study of Kepler light curves. However, the most used estimates in the Kepler Input Catalog (KIC) are not accurate enough for hot stars. Using a sample of B stars from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectral survey, we confirmed the systematic underestimation in KIC effective temperature and overestimation in KIC surface gravity. The good agreement between LAMOST and other follow-up observations proved the accuracy of effective temperature and surface gravity of B stars derived from LAMOST low-resolution spectra. By searching through LAMOST data, we found four misclassified main-sequence B stars in the Kepler field, which had been previously classified as A-type variables. We present spectroscopic and detailed frequency analysis of these four stars based on LAMOST spectra and Kepler photometry.