During extended intervals of Quiet Sun (QS) conditions, this programme seeks to observe the same area of chromospheric network for a long period so as to understand the long-term evolution of network elements and any related changes in coronal structures, particularly above the network cell boundaries. EIS will repeatedly obtain a combination of context images of the network in He II and other lines using a slot scan and detailed raster scans to cover an area of several network cells with the 1 arcsec slit and with exposure times of 60–90 s to register some of the weaker low temperature lines along with the major coronal lines. Line ratios will be employed to monitor plasma temperature and density at chromospheric and coronal temperatures. QS observations near disc centre will allow measurement of any related flow velocity patterns in the upper transition region and corona. SOT would provide Ca II images to register flows along with magnetograms to track the behavior of emerging flux and its interactions. XRT would take images at approximately one-minute cadence with the Al/Poly filter to provide continuing coronal context. The slot imaging part of this programme was run successfully over a five-day period in December/January 2008/09. |
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