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HINODE Operation Plan (HOP)

accepted on

20-dec-12


 HOP No.

 HOP title

HOP 0226

Diagnostics of Non-Maxwellian electron distributions in the solar corona

plan term

@ @

proposer

 name : Mackovjak, Dzifcakova, Dudik, Williams @  e-mail : mackovjak[at]fmph.uniba.sk
elena[at]asu.cas.cz
dudik[at]fmph.uniba.sk

contact person in HINODE team

 name : Williams @  e-mail : drw[at]mssl.ucl.ac.uk

 abstract of observational proposal
A commonly used assumption in interpretation of astrophysical spectra is that of Maxwellian distribution of particle energies. However, this assumption could be incorrect if the emitting system involves long-range or long-term interactions, or dynamic heating (e.g., Collier 2004, Leubner 2004, 2005, 2008). In the solar plasma, departures from Maxwellian distribution can occur at low plasma densities with strong gradient of plasma parameters or in the impulsive phase of solar flares. Moreover, a possible signature of dynamic heating in the solar corona should be a presence of non-Maxwellian distributions.

This proposal focuses on detection of the -distributions characterized by an asymptotically power-law high-energy tail. These distributions have been diagnosed in the Si III SUMER spectra of the transition region (Dzifcakova & Kulinova 2011), they provide better fit for the EIS line profiles (Lee et al. 2012), and are also observed in the solar wind (e.g. Maksimovic et al. 1997, Zouganelis 2008). We propose to use the diagnostic methods developed by Dzifcakova & Kulinova (2010) and Mackovjak et al. (2013), specifically designed for lines observed by the Hinode/EIS instrument. The selected lines involve line ratios that allow simultaneous determination of electron density, temperature and the value of .

 request to SOT
--

 request to XRT
Al-poly partial frame images encompassing the entire active region (512"x512"
or larger depending on the AR size), with cadence of ~3 min or longer, depending on telemetry allowance Al-poly, C-poly, Ti-poly, Be-thin, Be-med partial frame images at the beginning and end of the observation.

XRT observations will provide
- context information and allow for coalignment with other instruments,
- contraints for the high-temperatures in the DEM analysis based on the EIS+XRT data
- information about fast changes (heating events, brightenings) that could compromise the analysis of a particular 600s EIS exposure

 request to EIS
Scanning raster type
2" slit - to reduce errors due to photon statistics for very weak lines 60 s and 600 s exposures raster scanning the region 512" x 20" - the selected lines are very different in the number of counts. Both scans should observe the same region and without any interruptions, if possible.

For the main science observations, use studies KAPPA and KAPPA_SHORT. The slit should be located through the center of an active region near the center of the solar disk, encompassing the AR core, moss, and outlying coronal loops.

Because our exposures are very long, some additional calibration data will be required to monitor cosmic rays and hot/warm pixels.

Line list for diagnostics of for both scanning raster exposures

Ion Species and Wavelength (A) / Approximate Total Counts for Exposure (10 s)
(per pixel) - AR
Ca XVII 192.82 / 572.40
Fe XII 195.12 / 4240.80
He II 256.32 / 246.90
O IV 207.24 / 0.5
O IV 279.93 / 0.9
O V 271.04 /0.2
S X 180.73 / 3.6
S X 264.23 / 106.2
S XI 246.90 / 12.7
S XI 281.40 / 9.9
S XI 285.82 / 9.2
Ca XIV 193.87 / 163.1
Ca XV 176.92 / 0.7
Ca XV 200.98 / 71.2
Ar XIV 191.36 / 21.6
Ar XIV 194.39 / 67.4
Fe XI 182.17 / 61.2
Fe XI 188.23 / 747.9
Fe XI 257.77 / 7.9
Fe XII 186.85 / 222.0
Fe XIII 196.53 / 335.8
Fe XIII 202.04 / 729.6
Fe XIII 203.82 / 458.0

40" slot - the existing raster PRY_slot_context_v3 should be sufficient, FOV –
whole active region.

The observation should be run in following sequence:
1 x PRY_slot_context_v3, 1x KAPPA_SHORT, 1x KAPPA, 1 x KAPPA_SHORT, 1 x
PRY_slot_context_v3, Calibration observations

Repeating of whole observation in two consecutive days are desired (three days
in total). If necessary, this can be split across two OP periods.

 other participating instruments
SDO/AIA performing standard full-sun observations will supply additional information for temperature and DEM diagnostics.

SDO/HMI for magnetic field extrapolations

 remarks
Šimon Mackovjak will select pointing. Please, contact him before the running
of observations.
<kappa.def> <kappa_short.def>

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