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

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\subsection{Comparison with asteroseismology}\label{seismo}  Because both stars in KIC 9246715 are evolved giants with convective envelopes, we expect both to exhibit solar-like oscillations. These should be observable as p-modes in \emph{Kepler} long-cadence data. However, when \citet{gau13} and \citet{gau14} analyzed the oscillation The average large frequency separation of such  modes $\Delta \nu$ has been shown  to estimate global asteroseismic parameters, only one set scale with the square root  ofmodes was found. Of  the 15 oscillating red giants in eclipsing binaries in mean density of  the \emph{Kepler} field, KIC 9246715 is star, while  the only one with a pair frequency  of giant stars (the rest are composed maximum oscillation power $\nu_{\rm{max}}$ carries information about the physical conditions near the surface  of a giant the  star anda main sequence star). The oscillation spectrum  is shown in Figure \ref{fig:seismo}. \citet{gau14} note that the mode amplitudes are low ($A_{\rm{max}} \simeq 6.6$ ppm), report photometric variability as large as 2\%, a function of surface gravity  and speculate that star spots temperature \citep{cha13}. These so-called scaling relations  may be responsible for inhibiting oscillations on the smaller star. They also report $M = 2.06 \pm 0.13 \ M_{\odot}$ used to estimate a star's density  and $R = 8.10 \pm 0.18 \ R_{\odot}$ using the asteroseismic scaling relations surface gravity:  \begin{equation}  \left( \frac{R}{R_\odot} \frac{\rho}{\rho_{\odot}}  \right) \simeq \left(\frac{\nu_{\rm{max}}}{\nu_{\rm{max,\odot}}} \right) \left(  \frac{\Delta \nu}{\Delta \nu_\odot} \right)^{-2} \left( \frac{T_{\rm{eff}}}{T_{\rm{eff,\odot}}} \right)^{0.5}  \end{equation}\label{radeq} \nu_{\odot}} \right)^{2}  \label{density}  \end{equation}  and  \begin{equation}  \left( \frac{g}{g_{\odot}} \right) \simeq \left( \frac{\delta \nu_{\rm{max}}}{\delta \nu_{\rm{max}, \odot}} \right) \left{( \frac{T_{\rm{eff}}}{T_{\rm{eff}, \odot}} \right)}^{1.5}.  \label{gravity}  \end{equation}  However, when \citet{gau13} and \citet{gau14} analyzed the oscillation modes to estimate global asteroseismic parameters, only one set of modes was found. Of the 15 oscillating red giants in eclipsing binaries in the \emph{Kepler} field, KIC 9246715 is the only one with a pair of giant stars (the rest are composed of a giant star and a main sequence star). The oscillation spectrum is shown in Figure \ref{fig:seismo}. \citet{gau14} note that the mode amplitudes are low ($A_{\rm{max}} \simeq 6.6$ ppm), report photometric variability as large as 2\%, and speculate that star spots may be responsible for inhibiting oscillations on the smaller star. They also report $M = 2.06 \pm 0.13 \ M_{\odot}$ and $R = 8.10 \pm 0.18 \ R_{\odot}$ by rearranging the scaling relations in Equations \ref{density} and \ref{gravity}:  \begin{equation}\label{radeq}  \left( \frac{R}{R_\odot} \right) \simeq \left( \frac{\nu_{\rm{max}}}{\nu_{\rm{max,\odot}}} \right) \left( \frac{\Delta \nu}{\Delta \nu_\odot} \right)^{-2} \left( \frac{T_{\rm{eff}}}{T_{\rm{eff,\odot}}} \right)^{0.5}  \end{equation}  and  \begin{equation}\label{masseq}  \left(  \frac{M}{M_\odot} \right) \simeq {\left( \frac{\nu_{\rm{max}}}{\nu_{\rm{max,\odot}}} \right)}^{3} \left( \frac{\Delta \nu}{\Delta \nu_\odot} \right)^{-4} \left( \frac{T_{\rm{eff}}}{T_{\rm{eff,\odot}}} \frac {T_{\rm{eff}}} {T_{\rm{eff,\odot}}}  \right)^{1.5}. \end{equation}\label{masseq} \end{equation}  It is important to note the strong temperature dependence of these relations. WRITE SOMETHING ABOUT NEW M AND R ESTIMATES WITH BETTER TEMPERATURE INPUTS HERE. The masses and radii for both stars in KIC 9246715 are consistent with the asteroseismic values, so we unfortunately cannot use KIC 9246715 to draw conclusions about the accuracy the scaling relations. We speculate on which star is the oscillator and further explore the binary's co-evolutionary history in Section \ref{context}.