Oscillation mode frequencies of 61 main sequence and subgiant stars observed by Kepler

TL;DR

This paper presents detailed oscillation mode frequencies for 61 main sequence and subgiant stars observed by Kepler, using advanced analysis methods to improve stellar modeling and asteroseismic studies.

Contribution

It introduces a methodology for extracting and validating mode frequencies from multiple analysis methods and provides a comprehensive dataset for stellar oscillations.

Findings

Mode frequencies for 61 stars with error estimates

Development of a combined frequency extraction methodology

Assessment of fit quality using likelihood and Bayesian methods

Abstract

Solar-like oscillations have been observed by Kepler and CoRoT in several solar-type stars, thereby providing a way to probe the stars using asteroseismology. We provide the mode frequencies of the oscillations of various stars required to perform a comparison with those obtained from stellar modelling. We used a time series of nine months of data for each star. The 61 stars observed were categorised in three groups: simple, F-like and mixed-mode. The simple group includes stars for which the identification of the mode degree is obvious. The F-like group includes stars for which the identification of the degree is ambiguous. The mixed-mode group includes evolved stars for which the modes do not follow the asymptotic relation of low-degree frequencies. Following this categorisation, the power spectra of the 61 main sequence and subgiant stars were analysed using both maximum likelihood estimators and Bayesian estimators, providing individual mode characteristics such as frequencies, linewidths, and mode heights. We developed and describe a methodology for extracting a single set of mode frequencies from multiple sets derived by different methods and individual scientists. We report on how one can assess the quality of the fitted parameters using the likelihood ratio test and the posterior probabilities. We provide the mode frequencies of 61 stars (with their 1-sigma error bars), as well as their associated echelle diagrams.