patrick gaulme edited Discussion.tex  almost 9 years ago

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{\frac{g}{g_{\odot}}} \simeq {\left( \frac{\nu_{\rm{max}}}{\nu_{\rm{max}, \ \odot}} \right)} {\left( \frac{T_{\rm{eff}}}{T_{\rm{eff}, \ \odot}} \right)}^{1/2}.  \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 as well as its representation as an \'echelle diagram is shown in Figure \ref{fig:seismo} (I'LL SEND THE PLOTS). The mode amplitudes are quite low ($A_{\rm{max}}(l=0) \simeq 14$ ppm, and not 6.6 as erroneously reported by \citealt{gau14}) with respect to the 20 ppm we expectby supposing only one star oscillates,  based on the mode amplitude scaling relations (CORSARO ET AL 2013). 2013), and by supposing only one star oscillates.  Besides, the light curve displays a significant photometric relative variability as large as 2\% peak-to-peak. \citet{gau14} speculated that star spots may be responsible for inhibiting oscillations on the smaller star, as they observed on other five systems. Even though the star's oscillation was analyzed by \citet{gau14}, we reestimated $\nu_{\rm{max}}$ and $\Delta\nu$ in the same way, but by using the whole \textit{Kepler} dataset (Q0 to Q17). Differences with respect to previous estimates are minute but we keep the new ones as reference: $\nu_{\rm{max}} = 106.4 \pm 0.8$ and $\Delta\nu=8.31\pm0.01$. To determine mass, radius, surface gravity, and mean density, we use the scaling relations after correction of $\Delta\nu$ for the red-giant regime (CITE MOSSER 2012). In few words, instead of directly plugging the observed $\Delta\nu_{\rm{obs}}$ into the scaling equations, we estimate the asymptotic large spacing $\Delta\nu_{\rm{as}}$ as follows: $\Delta\nu_{\rm{as}} = \Delta\nu_{\rm{obs}} (1 + \zeta)$, where $\zeta = 0.038$. They also report $M = 2.06 \pm 0.13 \ M_{\odot}$ and $R = 8.10 \pm 0.18 \ R_{\odot}$ by assuming $T_{\rm{eff}} = 4857 \ \rm{K}$ and rearranging Equations \ref{density} and \ref{gravity} to yield  %\begin{equation} \label{radeq}