Beyond Gaia: Asteroseismic Distances of M giants using Ground-Based Transient Surveys
Abstract
Evolved stars near the tip of the red giant branch (TRGB) show solar-like oscillations with periods spanning hours to months and amplitudes ranging from 1 mmag to 100 mmag. The systematic detection of the resulting photometric variations with ground-based telescopes would enable the application of asteroseismology to a much larger and more distant sample of stars than is currently accessible with space-based telescopes such as Kepler or the ongoing Transiting Exoplanet Survey Satellite (TESS) mission. We present an asteroseismic analysis of 493 M giants using data from two ground-based surveys: the Asteroid Terrestrial-impact Last Alert System (ATLAS) and the All-Sky Automated Survey for Supernovae (ASAS-SN). By comparing the extracted frequencies with constraints from Kepler, the Sloan Digital Sky Survey Apache Point Observatory Galaxy Evolution Experiment (APOGEE), and Gaia we demonstrate that ground-based transient surveys allow accurate distance measurements to oscillating M giants with a precision of 15\%. Using stellar population synthesis models we predict that ATLAS and ASAS-SN can provide asteroseismic distances to 2×106 galactic M giants out to typical distances of 20-50 \; kpc, vastly improving the reach of Gaia and providing critical constraints for Galactic archaeology and galactic dynamics.