HOP 0137

abstract of observational proposal

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.

request to SOT

The objective for SOT would be to provide information on the evolution of the magnetic field at high spatial resolution and high sensitivity. The cadence for the EIS observations will be one raster approximately every 2 hours. For SOT the cadence should be somewhat greater, approximately one magnetogram every 10-20 minutes, depending on the available telemetry. The field of view should match that of the EIS raster. Ca images should be taken periodically for help with co-alignment.

request to XRT

The objective for XRT will be to provide additional information on the evolution of the observed emission. The XRT cadence and field of view should be chosen to match SOT's cadence and field of view. XRT images should be taken in a single thin filter, such as Open/Al-Poly.

request to EIS

Context:
Run IUU_SLOT_104x216_Q65; slot imaging raster; three 28 s exposures at adjacent positions overlapping by 8”; sample a FoV of 104” x 216” in approx 90 s.

Network Observation:
Run HPW_QS_MAP_v2_DPCM. Size – 120 arcsec x 300 arcsec. Duration 130 minutes.
Pair of studies repeated throughout the day at a cadence that utilizes the EIS available daily telemetry allocation. Observe when target area is within ± 0.5 days of central meridian. Track continuously for one day, even through SAA. Use enhanced compression to fit better the telemetry allocation.

remarks

Program: EIS long-term programme. Run for one day at approximately one month intervals when QS conditions are available near central meridian

Target: Region of QS at or near disc centre. Ideally observe when target area is within ± 0.5 days of central meridian. As far as possible track continuously for one day.