Authorea

Matteo Cantiello added SETTING_UP_FOR_THE_PRESENTATION__.tex almost 9 years ago

Commit id: 344c2fdbd5b6cdc88d89bd0f9f01541d3451c8e1

deletions | additions

%[SETTING UP FOR THE PRESENTATION OF THE DATA OR MOVE REWORDED VERSION TO AFTER FIG1.] However, a puzzling phenomenon arose from the observation of a few dozen %[44 ~22\%] stars showing little or no power in the dipole modes[REF Mosser/Droopy]. %, [but providing %only tentative conclusions that this phenomona probably concerns stars %more massive than 1.3\msol for which strong coupling between envelope and %core modes would increase the mode mass, reducing the observed amplitude.] Recent theoretical work shows good agreement with this mode suppression being caused by a near 100\% dissipative energy loss occurring in the core, and shows that strong magnetic fields in the core create a "greenhouse" effect that produces the required energy loss [REF theory paper]. %and provides a mechanism that can cause such an effect in the %presence of a strong core magnetic field near the hydrogen-burning shell[ref %theory paper]. %[maybe some more forward perspective what this could bring us, setting up %for the data next?] Figure 1 shows the oscillation power spectra of red giants at three different evolution stages where the smallest and least evolved stars are to the right and the largest and most evolved stars are to the left. For `normal' stars (top panels), the observed integrated power in the dipole modes (red peaks) is typically about 50-60\% larger than for the radial modes (black peaks) as usual in Kepler observations [ref Ballot2011/Mosser2012LargeKepler]. However, at each stage of we find stars with significantly suppressed dipole modes (bottom panels). % a phenomena previously observerved in X red giants % [refMosser2012LargeKepler] and a subgiant star [ref Droopy].