This combines observation plans for two different teams, one led by Habbal and Landi, and the other led by Sterling.
In addition, there will be two eclipses seen from Hinode:
Hinode Eclipse 1: 1st and 4th contact UT times 20:17:37.9 - 20:34:02.1 on 13 Nov, respectively.
Hinode Eclipse 2: 1st and 4th contact UT times 00:14:41.7 - 00:27:59.6 on 14 Nov, respectively.
OVERVIEW OF GROUND-BASED OBSERVATION PLANS:
A) Habbal & Landi Team:
The total eclipse taking place on 2012 November 13 (at around 20:30 UT) will be observed from the ground with a suite of filters designed to isolate and measure the intensity of visible lines from selected key ions like Fe X, XI, XIII and XIV between 5000 A to 11000 A. As the field of view of the observation extends from the limb up to 4 solar radii, these measurements will provide a unique window on the physical properties of the extended solar corona, providing us with AIA-like 2D images of the solar corona, which hold the additional advantages over AIA of 1) better spectral/temperature purity and 2) 10 times larger effective field of view.
Emission lines in the visible are formed by radiative scattering of disk emission starting from approximately 1.1 Rsun. The combination of visible spectral lines with 1) collisionally dominated EUV coronal lines from EIS and 2) visible observations of the background continuum will allow us to apply unique spectroscopic diagnostic techniques that will provide:
1 - The first ever empirical determination of fast and slow solar wind freeze-in heights for Fe;
2 - The empirical determination of the frozen-in Fe charge state composition to be directly compared with in-situ data;
3 - An empirical model of the fast and slow wind velocity, electron temperature and electron density profiles from the limb to the freeze-in region using the novel technique developed by Landi et al. 2012 (ApJ, 750, 159)
4 - Large scale distributions of plasma parameters (electron density, temperature and filling factor) in streamers and coronal holes.
COMP observations of the Fe XIII 10747 and 10800 line pair will allow the determination of the electron density below 1.5 solar radii to be compared with Hinode/EIS determinations, as well as cross-calibration between EIS, COMP and the eclipse observations.
We propose supporting observations from Hinode/EIS and Hinode/XRT during the eclipse, and for a few hours before and after the eclipse on 2012 November 13. The targets will be slowly evolving large-scale coronal structures (active region, streamer and coronal holes) before and after the eclipse. During the eclipse we would like to observe a prominence cavity at the limb, which will allow us to easily co-align EIS observations with eclipse images. In the absence of a cavity, we will observe an active region at the limb.
B) Sterling Team:
This team will observe the eclipse from the ground with a small group at Trinity Beach, near Cairns, Australia. Our observations will be of two types: medium resolution white light imaging of coronal plumes and cavities, and observations with polarizing filters to measure densities in the corona. The specific scientific objectives are twofold:
Project (1): Observe white-light coronal plumes, and compare with the source locations of X-ray jets. Raouafi et al. 2008 (ApJ, 682, L137) showed that over 90% of jets they observed occur at locations where polar plumes exist or soon form. We will use XRT to look for jets around the time of ground-based totality, to see whether there is a propensity for jets to occur around the bases of, e.g., the densest plumes (which would be the brightest plumes in white light, since the white-light intensity is strongly dependent upon density). The ground based observations will be done with a 106 mm aperture apochromatic refractor and Canon DSLR camera.
Project (2): we will use polarizing filters attached to a second Canon DSLR camera operating at a focal length of 800 mm. The polarizing data can be used to derive densities of coronal structures. In particular we would like to obtain densities of coronal cavities, and compare with coronal cavity properties obtained around the same time with EIS and XRT.
Specifically we request, from XRT: polar coronal hole observations appropriate for X-ray jet observations. These would be for a minimum of 2 hours, preferably one hour on either side of totality. Ideally the program would include ground-based totality time, but this is not essential for the scientific objectives (since the jets could presumably occur at any time within the plume during the plume's lifetime). A polar region to be targeted, with a preference for the north or the south pole being transmitted to the Hinode planners prior to the preliminary- and final-plan upload times. From EIS: Run of study gdz_plume1_2_300_50s (which is HOP 114 content) on one or two cavity targets. This could be run as soon as possible within a few hours of the ground-based totality time. Target locations will again be given to the Hinode planners prior to the times of the preliminary planning and final upload times.
Details of the requested Hinode observations are as follows.
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OVERVIEW OF HINODE OBSERVING PROGRAM
1) 13 Nov, 14:15---18:00 UT (can be shifted as needed to fit in EIS 3h 46m raster prior to synoptic). Streamer study. Limb pointing, at base of a streamer; targeting TBD by proposers.
2) 13 Nov, 18:00---18:10 UT (shifted as needed). Standard Hinode synoptic.
3) 13 Nov, 18:00---20:35 UT, Plume/jet observations. Include one EIS "coronal hole" scan.
Pointing at polar limb; north or south pole TBD by proposers.
4) 13 Nov, 20:15---20:40 UT, Hinode Eclipse 1; a public outreach program may be run (detailed plan and times from XRT team?).
5) 13 Nov, 20:40---22:00 UT, continue with (3) plume/jet study; only with XRT if EIS telemetry not available.
6) 13 Nov, 22:00---24:00 UT, observe a cavity. Cavity location TBD by proposers.
7) 14 Nov, 00:00---00:10 UT (shifted as needed). Standard Hinode synoptic.
8) 14 Nov, 00:10---00:31 UT, Hinode Eclipse 2; a public outreach program may be run (detailed plan and times from XRT team?).
9) 14 Nov, 00:35---01:45 UT, observe near-limb AR if available; alternatively observe a second cavity if available. Limb AR or cavity location TBD by proposers. Limb pointing.
End of eclipse observations.
Notes:
- All limb pointings to be as close as possible to the limb (15'').
- For EIS scans, the fine mirror mechanism can be used to point at targets.
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