Waves play an important role in the heating of the corona and in the acceleration of the fast solar wind from Coronal Holes (CHs). Thus far, only long period (10-70 min) radiance fluctuations have been detected in plumes and inter-plume regions, but nothing is known about higher frequency and/or lower amplitude variations and, whether or not these waves have also a signature in line-widths and line-shifts of emission lines. During April 2007, a previous version of this study has shown some evidence of radiance fluctuations propagating outward with a speed of about 60 km/s. The fluctuations seem to show a periodicity of 7 to 8 min.
Based on that experience we would like to apply for one or two additional runs of a modified version of the study. The modifications are based on the analysis of the April 2007 data. The study duration is of about 5 hours, to be executed one or two times during the campaign. Because of the requested VTT support (important but not indispensable to achieve the proposed science goals), we would request observing time during the 08:00 to 14:00 UT time frame (VTT prime time 08:00 to 11:00 UT). VTT observing time ends on November 2, so we would like to allocate our observations in the 30 Oct_ 02 Nov 2007 timeframe, if possible.
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