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تسجيل مستخدم جديدBeyond Gaia: Asteroseismic Distances of M giants using Ground-Based Transient Surveys
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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 $sim$1 mmag to $sim$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 textit{Kepler} or the ongoing Transiting Exoplanet Survey Satellite (textit{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 textit{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 $sim$15$%$. Using stellar population synthesis models we predict that ATLAS and ASAS-SN can provide asteroseismic distances to $sim$2$times$10$^{6}$ galactic M giants out to typical distances of $20-50 ; rm{kpc}$, vastly improving the reach of Gaia and providing critical constraints for Galactic archaeology and galactic dynamics.
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