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 expect by supposing only one star oscillates, based on the mode amplitude scaling relations (CORSARO ET AL 2013). 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}