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HINODE Operation Plan (HOP)

accepted on

30-jul-09

 HOP No.

  HOP title

HOP 0131
CORE: ToO: Helioseismology Observations of Coronal Hole with SOT

plan term

TOO
2009/10/11-2009/10/11
2009/10/24-2009/10/24

 　 　

proposer

  name : Harra, Zharkov & Sekii 　  e-mail : sekii[at]solar.mtk.nao.ac.jp

contact person in HINODE team

  name : Sekii 　  e-mail : sekii[at]solar.mtk.nao.ac.jp

 abstract of observational proposal
Short statement describing the observation and scientific justification: During this observation, the SOT continuously observes coronal hole boundary together with a patch of quiet Sun for at least 12 hours with constant cadence (about 1 min).  Taking continuous photospheric Dopplergrams of a coronal hole is needed for investigating the sub-photospheric properties of the CH by local helioseismology; apart from trying to establish the photospheric roots for the coronal feature by looking for subsurface flows and wave-speed in-homogeneities, we are also interested in seismic signatures of the open magnetic fields characteristic for coronal holes and in comparing such signatures with the results for plage region. Continuous observation of at least 12 hours is required to achieve good S/N ratio.

 request to SOT
~1-min cadence. Constant cadence is highly required for our helioseismology analyses.

Continuous observation for 12 hours at least.

Quiet Sun observations are needed for reference measurement. This is best achieved by observing the edge of the CH, making sure that a patch of quiet Sun is included in the FOV.

Ca II H measurements can be used for helioseismology of lower chromoshpere following Nagashima, et al, 2009 approach.
NFI: Fe I 557.6nm Dopplergram
BFI: Ca II H
If NFI takes 1024x512 Dopplergrams with 4x4 summing (Q65) and BFI takes 2048x1024 images with 2x2 summing (Q50) by using program ID:0x1f5( Mar 15 and Oct 11, 2008), estimated data volume is ~211Mbits per hour. We want to continue the observation at least 12 hours as long as telemetry permits.

Another choice is: only NFI takes 2048x1024 Dopplergrams with 2x2 summing for 12 hours. If the compression factor is set at Q75, estimated data volume is about 450Mbits per hour in this case.
SP: vector magnetograms covering NFI FOV

 request to XRT
XRT Bright point observations in dynamics mode if applicable

 request to EIS
Simultaneous EIS observations: study ID 391 but for equatorial CH (js_ch_400x256_v4)

Slit: 2"
Step Size: 2"
Exposure time: 160 sec

Lines: FeX, FeVIII, FeXI, CaXVII, FeXII, FeXIII, OV, HeII, FeXIV, Fe XIV, MgVII, OIV, FeXV

Pointing: Coronal Hole Boundary

 other participating instruments

 remarks
Time period of proposed observations, if required: No preference.

Time window in day, if required: No preference.

Target of interest: Coronal Hole Boundary, Bright Points (long lived). (TOO)

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