HOP 0379

HINODE Operation Plan (HOP)

accepted on

27-jun-2019

abstract of observational proposal

Main Objective: To characterize the coronal hole (polar or on-disk) photospheric magnetic field properties with the aim to improve the heliospheric open magnetic flux estimate.

Scientific Justification: The heliospheric open magnetic flux (OMF) based on moderate-resolution magnetograms was found to be grossly underestimated compared to in situ observation. Possible explanations include systematics in the spectropolarimetry inference. We propose to observe the coronal hole (CH) photospheric field using Hinode/SP (Fe I 630 nm) in coordination with BBSO/GST (Fe 1.56 μm). The high spatial/spectral resolution data probing two different heights will allow for a systematic investigation of various systematics (e.g., radial field assumption, stray light, noise), and are expected to improve the OMF estimate. This work is an integral component of a recent NSF grant, in which Hinode and NST data are used to train a PhD student in preparation for the imminent DKIST operation.

request to SOT

1. For polar CH, SOT-SP FoV 320” x 164”, Pixel size: 0.16”/pix, Binning: 1x1, Single side mode, exposure: 12.8 sec (16 Cycles). This is identical to HOP 0081.

2. For on-disk CH, the configuration is the same. FoV may be reduced to match the CH dimension.

3. Minimum output: one northern polar CH map and one on-disk CH (if available) map.

remarks

Dates:
1. September 19 - 23, 2019 (BBSO/GST allocated observing time)
2. Co-temporal observation with GST is desired but not required

Time window: 15:00 - 24:00 UT (BBSO noon at about 19:40 UT)

Target(s) of interest:
1. Polar CH or on-disk CH
2. On-disk CHs will be ToO. Locations can be estimated 1-2 days ahead using SDO data

The polar CH observation is identical to HOP 0081 (expected to run for 1-2 days in early September). Priority should be given to deeper integration over large FoV.