# Prospects for Galactic and stellar astrophysics with asteroseismology of giant stars in the TESS Continuous Viewing Zones and beyond

Prospects for Galactic and stellar astrophysics with asteroseismology of giant stars in the TESS Continuous Viewing Zones and beyond
See arXiv version
15 Pages (+6 Pages Appendices), 14 Figures (+3 in Appendices). Re-submitted to MNRAS following positive initial review. Full catalogue with seismic parameters, mass and age estimates available at this https URL

### Abstract

The NASA-$$\it{TESS}$$ mission presents a treasure trove for understanding the stars it observes and the Milky Way, in which they reside. We present a first look at the prospects for Galactic and stellar astrophysics by performing initial asteroseismic analyses of bright ($$G < 11$$) red giant stars in the $$\it{TESS}$$ Southern Continuous Viewing Zone (SCVZ). Using three independent pipelines, we detect $$\nu_{\mathrm{max}}$$ and $$\Delta\nu$$ in 41% of the 15,405 star parent sample (6,388 stars), with consistency at a level of $$\sim 2\%$$ in $$\nu_{\mathrm{max}}$$ and $$\sim 5\%$$ in $$\Delta\nu$$. Based on this, we predict that seismology will be attainable for $$\sim 3\times10^{5}$$ giants across the whole sky, subject to improvements in analysis and data reduction techniques. The best quality $$\it{TESS}$$-CVZ data, for 5,574 stars where pipelines returned consistent results, provide high quality power spectra across a number of stellar evolutionary states. This makes possible studies of, for example, the Asymptotic Giant Branch bump (AGBb). We demonstrate that mixed $$\ell=1$$ modes and rotational splitting are cleanly observed in the 1-year data set. By combining $$\it{TESS}$$-CVZ data with $$\it{TESS}$$-HERMES, $$\it{SkyMapper}$$, APOGEE and $$\it{Gaia}$$ we demonstrate the potential for Galactic archaeology studies using the data, which provides good age precision and accuracy that reproduces the age of high $$\mathrm{[\alpha/Fe]}$$ stars and relationships between mass and kinematics from studies based on $$\it{Kepler}$$. Better quality astrometry and simpler target selection than the $$\it{Kepler}$$ sample makes this data ideal for studies of the local star formation history and evolution of the Galactic disc. These results provide a strong case for detailed spectroscopic follow-up in the CVZs to complement that which has been (or will be) collected by current surveys. [Abridged]