this is for holding javascript data
Matteo Cantiello edited Mode Visibility.tex
almost 9 years ago
Commit id: d343c1a008eafb52be7e358ca4fffac885d1813c
deletions | additions
diff --git a/Mode Visibility.tex b/Mode Visibility.tex
index bdfec35..3a193c3 100644
--- a/Mode Visibility.tex
+++ b/Mode Visibility.tex
...
where $\Delta \nu \simeq (2 t_{\rm cross})^{-1}$ \cite{Chaplin_2013} is the large frequency separation between overtone modes, and $\tau$ is the damping time of a radial mode with similar frequency. The value of $T^2$ can be calculated from a stellar model, whereas {\bf $\tau \approx 5 \! - \! 10 \, {\rm days}$} {\bf \cite{Dupret_2009,Corsaro_2012,Grosjean_2014,Corsaro_2015} } for stars ascending the RGB.
Most observed modes are near the frequency $\nu_{\rm max}$, which is determined by the evolutionary state of the star. On the RGB, more evolved stars generally have smaller $\nu_{\rm max}$.
Figure \ref{fig:moneyplot} compares our estimate for suppressed dipole mode visibility (equation \ref{eqn:vis}) with {\it Kepler} observations \cite{Mosser_2011,Garcia_2014}. The {\bf objects
classified identified by \cite{Mosser_2011} as
suppressed depressed dipole
modes (DDM)} modes} stars lie very close to our estimate. The striking agreement holds over a large baseline in $\nu_{\rm max}$ extending from the very early red giants KIC 8561221 \cite{Garcia_2014} and KIC 9073950 at high $\nu_{\rm max}$ to near the luminosity bump at low $\nu_{\rm max}$.
We conclude that the cores of stars with
suppressed {\bf depressed} dipole modes efficiently trap waves tunneling through the evanescent region. This is further supported by
the their normal $\ell=0$ mode visibility
in suppressed pulsators (because radial modes do not propagate within the inner core) and the lack (or perhaps smaller degree) of
suppression {\bfdepression} observed in $\ell=2$ modes by \cite{Mosser_2011}, because quadrupole modes have a smaller transmission coefficient $T$.
An additional consequence is that the larger effective damping rate for suppressed modes will lead to larger line widths in the oscillation power spectrum. The linewidth of a suppressed mode is $\tau^{-1} + \Delta \nu T^2_{\ell}$ and is generally much larger than that of a non--suppressed mode. The suppressed dipole modes in KIC 8561221 \cite{Garcia_2014} indeed have much larger linewidths than non-suppressed dipole modes in similar stars.
...