The K2 Asteroseismic KEYSTONE sample of Dwarf and Subgiant Solar-Like Oscillators. I: Data and Asteroseismic parameters

• Main Authors: Lund, Mikkel N, Basu, Sarbani, Bieryla, Allyson, Casagrande, Luca, Huber, Daniel, Hekker, Saskia, Viani, Lucas, Davies, Guy R, Campante, Tiago L, Chaplin, William J, Serenelli, Aldo M, Ong, J. M. Joel, Ball, Warrick H, Stokholm, Amalie, Bellinger, Earl P, Bazot, Michaël, Stello, Dennis, Latham, David W, White, Timothy R, Sayeed, Maryum, Børsen-Koch, Víctor Aguirre, Chontos, Ashley
• Format: Journal Article
• Language: English
• Published: 29-05-2024
• Subjects: Physics - Solar and Stellar Astrophysics
• DOI: 10.48550/arxiv.2405.15919

The KEYSTONE project aims to enhance our understanding of solar-like
oscillators by delivering a catalogue of global asteroseismic parameters
(${\Delta\nu}$ and ${\nu_{\rm max}}$) for 173 stars, comprising mainly dwarfs
and subgiants, observed by the K2 mission in its short-cadence mode during
campaigns 6-19. We derive atmospheric parameters and luminosities using
spectroscopic data from TRES, astrometric data from $\textit{Gaia}$, and the
infrared flux method (IRFM) for a comprehensive stellar characterisation.
Asteroseismic parameters are robustly extracted using three independent
methods, complemented by an iterative refinement of the spectroscopic analyses
using seismic ${\log g}$ values to enhance parameter accuracy. Our analysis
identifies new detections of solar-like oscillations in 159 stars, providing an
important complement to already published results from previous campaigns. The
catalogue provides homogeneously derived atmospheric parameters and
luminosities for the majority of the sample. Comparison between spectroscopic
${T_{\rm eff}}$ and those obtained from the IRFM demonstrates excellent
agreement. The iterative approach to spectroscopic analysis significantly
enhances the accuracy of the stellar properties derived.