000004167 001__ 4167
000004167 005__ 20190405155349.0
000004167 037__ $$aSEMIN-2019-0020
000004167 100__ $$aDolla, Laurent
000004167 245__ $$aHinode/EIS measurements of the preferential heating of minor ions in the low corona to test the role of different wave-particle mechanisms
000004167 260__ $$c2019
000004167 269__ $$c2019-04-04
000004167 520__ $$aPreferential heating of minor, heavy ions has long been observed in the solar wind, both through in situ measurements from 0.3 to several Astronomical Unit and through remote-sensing observation closer to the Sun (up to a few solar radii). Wave-particle interactions (e.g. non-adiabatic acceleration by kinetic Alfvén waves, resonant interaction with ion-cyclotron waves...) are likely candidates to explain this heating, and could contribute to the heating of the solar corona and acceleration of the fast solar wind. As each kind of wave-particle interaction leads to different heating rates as a function of the ion charge-to-mass ratio (q/m), the analysis of the ion temperatures of different minor ions of the corona is a key to solve the heating and acceleration mechanisms of the fast solar wind. We extended the work of Dolla et al. (2008, 2009) by using the Hinode/EIS spectrometer to measure the spectral line widths of coronal ions the  above the solar limb. From the line widths we then derive the width of the kinetic distributions averaged along the line of sight, which is a combination of the ion temperature and any plasma motion like those induced by MHD waves. Our results confirm the trend of preferential heating of the ions: the lower the q/m, the higher the temperature. We compare this trend in coronal holes and quiet Sun regions and we also compare the temperatures of minor ions with those of the protons (as deduced from the asymptotic limit of the temperature at largest q/m) and of the electrons. 
000004167 536__ $$aPEA/$$c4000120800/$$f4000120800
000004167 594__ $$aSTCE
000004167 773__ $$tCmPA, KULeuven
000004167 8560_ $$flaurent.dolla@observatoire.be
000004167 980__ $$aSEMIN