Meredith L. Rawls edited Discussion.tex  over 8 years ago

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\subsubsection{Mixed-modes analysis}  \label{subsubsec_mixed}  Based on the distribution of mixed \revise{$\ell = 0$} modes, \citet{gau14} reported that the oscillation pattern period spacing was typical of that of a star from the secondary red clump, i.e., a core-He-burning star that has not experienced a helium flash. However, this conclusion was based on a period spacing of $\Delta \Pi \simeq 150 \ \rm{sec}$, which is difficult to measure robustly from a noisy oscillation spectrum. Red giant branch stars have smaller period spacings than red clump stars, and ($\Delta \Pi = 150 \ \rm{sec}$, $\Delta \nu = 8.31 \ \mu \rm{Hz}$) puts the oscillating star on the very edge of the asteroseismic parameter space that defines the secondary red clump \citep{mos14}. Therefore, while asteroseismology does indicate the oscillator in KIC 9246715 is a red clump star, there is a large uncertainty attached to the classification. This result is supported statistically by \citet{mig14}, who report it is more likely to find red clump stars than red giant branch stars in asteroseismic binaries in \emph{Kepler} data. This is largely due to the fact that evolved stars spend more time on the horizontal branch than the red giant branch. We note that due to the large noise level of the mixed modes, we are unable to measure a core rotation rate in the manner of \citet{bec12} and \citet{mos12}.  \revise{MEREDITH MOVED THE PARAGRAPH ABOVE FROM SECTION \ref{subsubsec_main_osc} AND OMITTED THE CITATION TO (Mosser, Private Communication).}  {\textbf{ENRICO}}  For \revise{For  assessing the evolutionary stage of KIC~9246715 we have first performed a Bayesian fit to the individual oscillation modes of the star using the \textsc{D\large{iamonds}} code \cite{Corsaro14} \cite{cor14}  and the methodology for the peak bagging analysis of a red giant star presented by \cite{Corsaro15cat}. \cite{cor15}.  Then we have compared the set of the obtained frequencies of mixed dipole modes with those from the asymptotic relation proposed by Mosser, B., Goupil, M. J., Belkacem, K., et al. 2012b, A&A, 540, A143, which we computed using different values of $\Delta\Pi_1$, the period spacing of dipole gravity modes. The result showed a significant better matching when values of $\Delta\Pi_1$ around 200\,s were used, hence confirming that the star is settled on the He-burning phase of the stellar evolution. evolution.}  \subsubsection{Identifying the oscillating star}\label{identifying}  The asteroseismic mass and surface gravity are consistent with those from the ELC model for both stars, while the asteroseismic radius is only consistent with Star 2. Neither star's mean density agrees with the asteroseismic value, but Star 2 is much closer than Star 1. Overall, our asteroseismic analysis suggests the oscillating star is Star 2. However, we cannot definitely conclude this without considering the temperature dependence of the scaling relations. From \citet{gau13}, \citet{gau14}, and the present work, asteroseismic masses and radii were reported to be $(1.7 \pm 0.3 \ M_\odot, 7.7 \pm 0.4 \ R_\odot)$, $(2.06 \pm 0.13 \ M_\odot, 8.10 \pm 0.18 \ R_\odot)$, and $(2.17 \pm 0.12 \ M_\odot, 8.26 \pm 0.16 \ R_\odot)$, respectively. Among these, $\nu_{\rm{max}}$ does not vary much ($102.2, 106.4, 106.4 \ \mu\rm{Hz}$), and $\Delta \nu$ varies even less ($8.3, 8.32, 8.31 \ \mu\rm{Hz}$), while the assumed temperatures were 4699 K (from the KIC), 4857 K (from \citealt{hub14.2}), and 5000 K (this work).