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HINODE Operation Plan (HOP)

accepted on


 HOP No.

 HOP title

HOP 0376

Polar Plume Observations During the 2019 July 2 Total Solar Eclipse

plan term


@ @


 name : Sterling, Pasachoff @  e-mail : alphonse.sterling[at]nasa.gov, jay.m.pasachoff[at]williams.edu

contact person in HINODE team

 name : Savage, Watanabe, De Pontieu @  e-mail : sabrina.savage[at]nasa.gov, watanabe.tetsuya[at]nao.ac.jp, bdp[at]lmsal.com

 abstract of observational proposal
Main Objective: Observations of solar polar plumes in X-rays, to supplement ground-based visible-light observations of the total solar eclipse of 2019 July 2 from Chile.

Scientific Justification: The coronal intensity in white light is a strong function of density alone, while the coronal intensity seen from Hinode/XRT is dependent on temperature and density. We want to know whether XRT-observed coronal features such as X-ray jets have a propensity to occur in the densest plumes. We can address this by combining the ground-based and space-based observations during the eclipse. Our focus is on the study of coronal jets (e.g., Sterling et al. 2015, Nature, 523, 437), and their possible connection to plumes (e.g., Raouafi et al. 2008, ApJ, 682L, 137, Hanaoka et al. 2018, ApJ, 860, 142; also see Pasachoff et al. 2008, ApJ, 682, 638, and Pasachoff et al. 2015, ApJ, 800, 90).

 request to SOT

 request to XRT
TARGET: First choice is a PCH. If no PCH is available, then target should be quiet-Sun polar region. If two PCHs are visible, then the one in which the hole is largest and/or best visible (gdarkesth in EUV and X-ray images) should be selected.

TIMING: Request >~ 2 hours (longer if possible) on polar coronal hole (or polar quiet Sun) region, before and after totality. It is sufficient to have the observations within a few hours of totality (20:39 UT in Chile).

FIELD OF VIEW: 512x512 desired (384x384 acceptable)
EXPOSURE TIME: Long exposure time (AEC setting = 2)
FILTERS: Al/poly and Al/mesh.
CADENCE: About 30 seconds between images would be acceptable.
CONTEXT IMAGES: In addition to the PCH images, it is vital to have full-Sun  

XRT images for context and alignment.  These could be obtained with a typical XRT synoptic observation sequence, but as a minimum images in two filters, Al_poly and Al_mesh, are required.  Two sets of images should be obtained, one prior to the ground-based eclipse, and another after the ground-based eclipse.

 request to EIS

 other participating instruments
IRIS requests:  
Complementary (to observe jets in PCHs).

Additional instrument coordination:  
Ground-based observations from Chile by the proposers.

Dates:  2019 July 2 (may extend into July 3).

Time window:  At least 2 hrs (ignoring Hinode eclipses) of PCH observations.  Preferably one 2-hr+ block before totality and a second 2-hr+ block after totality.  (Totality on the ground in Chile will be at ~20:39 UT).  In addition, two sets of XRT full-disk images should be taken for context in-between the two blocks.  

The sequences should be as close to totality as possible, but because plumes are persistent (lasting several hours), within a few hours of either side of totality is sufficient.

Target(s) of interest:  Polar plumes, and jets around those plumes, are the target.  Pointing should be at a polar coronal hole (PCH) region, similar to HOP 339.  If two PCHs are visible, select the one that is

Previous HOPs:  
HOP 339.  (Data from that HOP were used in Hanaoka et al. 2018, ApJ, 860, 142.)

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