Meredith L. Rawls edited Conclusion.tex  almost 9 years ago

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\section{Conclusions}\label{conclude}  Red giants are ideal beacons for probing We characterize  the Milky Way Galaxy via asteroseismology. However, more than half of cool stars should be in double red giant eclipsing  binary or multiple systems, so galactic studies must be done carefully due to external influences of binarity on solar-like oscillations. Detailed studies KIC 9246715 with a combination  of light curve + radial velocity modeling, stellar atmosphere modeling, and global asteroseismology, and investigate  the handful of known RG/EBs are crucial to ensure we understand role magnetic activity, tidal forces, and stellar evolution have had in creating  the physical properties system we observe today. KIC 9246715 represents a likely future state  of these galactic beacons. In fact, RG/EBs are similar-mass RG/EB systems and raises interesting questions about  the only stars that enable us to measure their global physical properties with two independent methods. interactions among magnetic activity, tides, and solar-like oscillations.  To this end, the double red giant eclipsing binary KIC 9246715 is a useful case study. The two stars in KIC 9246715  are nearly twins ($M_1 = 2.16 \pm 0.04\ M_{\odot}$, $M_2 = 2.14 \pm 0.03\ M_{\odot}$, $R_1 = 7.90 \pm 0.04 \ R_{\odot}$, $R_2 = 8.33 \pm 0.04 \ R_{\odot}$), yet we observe only one pair of solar-like oscillations. oscillations ($M = 2.17 \pm 0.13 \ M_{\odot}$, $R = 8.26 \pm 0.16 \ R_{\odot}$).  The oscillations are therefore  most likely from Star 2, theslightly  larger and cooler of the pair.  WRITE MORE WORDS HERE.  This supports the idea of magnetically-active stars having low-amplitude solar-like oscillations or none at all.  Our detailed light curve pair, which may also be less magnetically active than Star 1. Surface gravity measurements from photodynamic modeling  and radial velocity modeling...   The fact that only one star asteroseismology nearly agree (x and x, respectively), while the measured surface gravity from stellar atmosphere modeling  is oscillating points significantly higher (x). A discrepancy similar  to how tidal activity may affect oscillations. this is found in a population study comparing asteroseismic and spectroscopic surface gravities \citep{hol15}, but the physical cause is uncertain.  The stars were born and evolved together, but the present evolutionary state (red giant branch vs. red clump) is unclear. Tidal circularization timescales and radii from a stellar evolution model indicate that both stars should be on the red giant branch with an age of $7.28 \times 10^8$ years, while the oscillation mode period spacing---which is difficult to measure due to a weak and noisy oscillation spectrum---suggests the oscillating star may be on the red clump. Future work will examine this disagreement in more detail with precise ``peak-bagging'' of individual oscillation modes.  Red giants are ideal beacons for probing the Milky Way Galaxy via asteroseismology, so it is crucial that we understand the accuracy and precision of asteroseismically-derived physical parameters. Along the same lines, more than half of cool stars should be in binary or multiple systems, so galactic studies must be done carefully due to external influences of binarity on solar-like oscillations. Detailed studies of the handful of known RG/EBs are crucial to ensure we understand these galactic beacons. Future work will characterize the other 14 known oscillating RG/EBs as well as several non-oscillating RG/EBs. These have the potential to become some of the best-studied stars while simultaneously helping us better understand the structure of the Milky Way.