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HINODE Operation Plan (HOP)

accepted on

24-May-07


 HOP No.

 HOP title

HOP 0019

a) Search for fast magnetoacoustic waves in active region loops & b) Loop density measurement (target of opportunity)

plan term

target of opportunity

@ @

proposer

 name : J. G. Doyle
E. O'Shea
@  e-mail : jgd[at]star.arm.ac.uk

contact person in HINODE team

 name : J. L. Culhane @  e-mail : jlc[at]mssl.ucl.ac.uk

 abstract of observational proposal
Science case a): Using the strongest lines present in the EIS spectrum, we look for fast magnetoacoustic waves in active region loops. We use a small number of lines to try and keep the cadence of the observations as low as possible. We note, for example, that Roberts et al. (1984) predict the fast sausage wave to have a period of the order of one second. We shall find out the signature of different modes of the fast acoustic oscillations, i.e., kink and sausage modes of the oscillations. The measurements of oscillation period and other observational parameters, along with basic flux tube MHD theory and coronal seismology, will allow us the more sophisticated easurements of the magnetic field in solar atmosphere with Hinode. We attempt here to find these fast oscillations using EIS and as a test of the EIS temporal resolution.The additional observations with very hot flare lines will also explore the hot loop oscillations and give a chance to study its possible drivers. We use the 40" slot so as to obtain images of the active region loops. We will look for material flows/waves in these loops at speeds appropriate to those of fast MHD waves, e.g., using difference images.
Science case: Here we will measure densities in the active region loops in the form of time series obtained with the 40" slot. These densities are necessary in order to enable us to obtain estimates of magnetic field strength in the magnetic loops, using the periods of oscillation previously measured from the arm_fastslot_waves study. These observations are also interesting as a test of the different density diagnostic present in the EIS spectrum. We will test three different diagnostics here, Fe XII 186.9/195.1, Fe XIII 203.8/202.0 and Fe XIII 196.54/202/04. We are also interested in finding locations in the active region loops where there are localised density increases which may be indicators of magnetic reconnection.
Science case b): Here we will measure densities in the active region loops in the form of time series obtained with the 40" slot. These densities are necessary in order to enable us to obtain estimates of magnetic field strength in the magnetic loops, using the periods of oscillation previously measured from the arm_fastslot_waves study.

 request to SOT
a) SOT 100" x 50" FOV with G-band, Ca II H, and 6302 magnetograms at about 30 seconds cadence for the duration of the run; tracking

b) SOT 100" x 50" FOV with G-band, Ca II H, and 6302 magnetograms at about 30 seconds cadence for the duration of the run .. tracking

 request to XRT
a) Use XRT in a reduced FOV mode so that movies may be obtained of the active region in X-ray with a high cadence.
FOV: 384x384
Single filter (Al_poly) ~ 10s cadence
Context thicker filter (Al_Poly + Ti_Poly) every ~15 minutes
Lossless compression; tracking

b)Use XRT in a reduced FOV mode so that movies may be obtained of the active
region in X-ray with a high cadence.
FOV: 384x384
single filter (Al_poly) ~ 20s cadence
Context thicker filter (Al_Poly + Ti_Poly) every ~15 minutes
Lossless compression;  tracking

 request to EIS
a)
arm_raster_ar       duration  20m
arm_fastslot       duration  1h11m
arm_fastslot       duration  1h11m
arm_raster_ar       duration  20m
arm_fastslot       duration  1h11m
arm_fastslot_ar     duration  1h11m
arm_raster_ar       duration  20m
Total Duration: 5h42m
raster: arm_fastslot

Slit: 40" slot
Window height: 200 pixels
Window width: 56 pixels
Exposure time: 2s
Rotation compensation: off
No. of exposure sets: 1000
Total duration of study: 1h11m
Compression: JPEG(Q=98)
Data Rate: 48 kBits/s

Species    Wavelength  Total Counts    Window width
              (A)          (per pixel/s)
Ca XVII         192.82           57               56
Fe XII         195.12         424               56
He II           256.32           12               56
Si VII         275.35          12               56
Fe X           184.54           23               56
Fe XIII         203.8             46               56
Fe XV           284.16         126               56
FE XVI         262.9             30               56

raster:   arm_raster_ar
Window width: 56 pixels
Window height: 400 pixels
Exposure time: 25s for AR
Slit: 2" slit
Number of fine mirror steps: 40
Rotation compensation: Off
Total duration of study: 20m
Compression: lossless
Data rate: 54 kBits/s

Species    Wavelength (A)  Total Counts/pixel/s)   Window width
Ca XVII         192.82           57               56
Fe XII         195.12                  424                   56
He II           256.32           12               56
Mg VI           270.40              1             56
Si VII         275.35                         12               56
Fe X           184.54           23               56
Fe XII         186.88           22               56
Fe XIII         203.8             46               56
Fe XIII         202.04           73               56
Fe XV           284.16                  126               56
Ca XIV         193.87           16               56

b)
arm_raster_ar             20m
arm_loop_ne_slot        1h28m
arm_loop_ne_slit         24m
arm_loop_ne_slot        1h28m
arm_loop_ne_slit         24m
arm_raster_ar               20m
Total Duration:             4h25m

raster:  arm_loop_ne_slot
Target: Active region on disk with many visible loops
Slit: 40" slot
Window height: 400 pixels
Window width:  56 pixels
Exposure time: 15 sec
Rotation compensation: On
No. of exposure sets: 300
Total duration of study: 1h28m
Compression:  lossless
Data rate:46 kBits/s

Ion Species    Wavelength       Total Counts    Window width
              (A)                  (per pixel/s)
Ca XVII         192.82               57               56
Fe XII         195.12                424             56
He II           256.32                  12               56
Fe XII         186.88                  36               56
Fe XIII         196.54                  33               56
Fe XIII         203.8                    45               56
Fe XIII         202.04                  72               56

raster:  arm_loop_ne_slit
Target: Active region on disk with many visible loops
Slit: 2"
Window height: 400 pixels
Window width:  56 pixels
Exposure time: 45 sec
Rotation compensation: On
No. of exposure sets: 30
Total duration of study: 24m
Compression:  lossless
Data rate:16 kBits/s
Ion Species    Wavelength       Total Counts    Window width
                   (A)              (per pixel/s)
Ca XVII         192.82           57              56
Fe XII         195.12                    424              56
He II           256.32           12              56
Fe XII         186.88           36              56
Fe XIII         196.54           33              56
Fe XIII         203.8             45              56
Fe XIII         202.04           72              56

raster:   arm_raster_ar
Window width: 56 pixels
Window height: 400 pixels
Exposure time: 25s for AR
Slit: 2" slit
Number of fine mirror steps: 40
Rotation compensation: Off
Total duration of study: 20m
Compression: lossless
Data rate: 54 kBits/s

Species    Wavelength   Total Counts    Window width
              (A)                   (per pixel/s)
Ca XVII         192.82           57              56
Fe XII         195.12                    424              56
He II           256.32           12              56
Mg VI           270.40            1              56
Si VII         275.35           12              56
Fe X           184.54           23              56
Fe XII         186.88           22              56
Fe XIII         203.8             46              56
Fe XIII         202.04           73              56
Fe XV           284.16                    126              56
Ca XIV         193.87           16              56

 other participating instruments

 remarks
Target a): Active region on disk showing many distinct loops, area to be imaged must include evidence of loops

Target b): Active region on disk with many visible loops

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