Meredith L. Rawls edited Introduction.tex  over 9 years ago

Commit id: 7ba8221b7b755209f093e99ea0210c3b9425e18e

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% EBs are really awesome w/Kepler too  \emph{Kepler}'s primary science goal is to find Earth-like exoplanets orbiting sun-like stars \citep{bor10}. However, in addition to successes in planet-hunting and suitability for red giant asteroseismology, \emph{Kepler} is also incredibly useful for studies of eclipsing binary stars. In fact, \emph{Kepler} has discovered numerous long-period eclipsing systems from consistent target monitoring over several years. Eclipsing binaries are extremely important tools for understanding fundamental stellar properties, and in turn for testing stellar evolutionary models or determining distances. When radial velocity curves exist for both stars in an eclipsing binary, along with a well-sampled light curve, a full orbital solution can be found. Accurate masses and radii are straightforward to derive from such a solution; indeed, Kepler's third law applied in this way is the \emph{only} direct method for measuring stellar masses.  Taken together, red giants in eclipsing binaries (hereafter RG/EBs) that exhibit solar-like oscillations are an ideal testbed for asteroseismology. There are presently 15(?) 15  known RG/EBs that show solar-like oscillations \citep{gau13,gau14}. All of these have orbital periods ranging from tens to hundreds of days, and are found in the \emph{Kepler} field of view. % Overview of paper  In this paper, we present physical parametersfrom a photodynamic model  for the unique RG/EB KIC 9246715, which contains two red giant stars giants  in a 171.3-day orbital period. Interestingly, only eccentric orbit. Only  one of the two stars shows solar-like oscillations, and with a lower amplitude than expected. We find good agreement between eclipsing binary photodynamic  models and asteroseismology for the oscillating star's mass ($M_{\rm{EB}} ($M_{\rm{Phot}}  = 2.11 \pm 0.02 \ M_{\odot}$, $M_{\rm{seismo}} = 2.06 \pm 0.13 \ M_{\odot}$) and a notable discrepency in radius ($R_{\rm{EB}} ($R_{\rm{Phot}}  = 9.95 \pm 0.13 \ R_{\odot}$, $R_{\rm{seismo}} = 8.10 \pm 0.18 \ R_{\odot}$). With this in mind, we explore how the likely presence of star spots and moderate tidal effects influence the oscillations. In \S \ref{data}, we describe how we acquired acquire  and processed process  photometric and spectroscopic data, while and  \S \ref{rvs} explains our radial velocity extraction process. In \S \ref{atm}, we disentangle each star's contribution to the spectra to perform stellar atmosphere modeling. We then present our final orbital solution and physical parameters for KIC 9246715 in \S \ref{model}. Finally, \S \ref{discuss} compares our results with those from asteroseismology and discusses the connection between solar-like oscillations and effects such as star spots and tidal forces.