Hinode Active Region Heating

Active Region heating

To observe the velocity field and density variations in an active region and relate results
to active region heating models. A wide range of active region science will be possible
with EIS, including the structure of coronal loops, searches for nanoflares,
identification of wave phenomena, measurement of coronal velocity fields. The programs
listed here provide general studies that are suitable for these science topics.

Consists of three different sit-and-stare sequences. Each sequence should be run on different
areas in the active region, including the neutral line, plage, sunspots and coronal loops.
The high effective area of EIS, particularly in the EIS-B channel, is especially suited to
uncovering rapid variability in coronal structures, and high cadence density measurements will
be possible for the first time.

Consists of two raster studies, both for a large scale overview of an active region, and a
higher cadence study of localised areas.

Is a deep exposure raster on an entire active region to determine the velocity fields in the corona.

In order to improve the cadence of the active region studies and take advantage of the high
sensitivity of EIS, each of the studies has the following parameters:

Wavelength windows: 16 pixels
Y=256" (along slit)
These allow 7 lines to be taken in a 4 sec exposure.
A context slot raster is recommended for each of the programs to be run
at the start and end of the sequence. This raster is defined as
Slit: 40" slot X=240"; 40" steps
Wavelength windows: 40 pixels
Exposure time: 10 sec
Duration: 1 min
Line list: (7 lines same as Program 1b)



Line	Wavelength
He II	256.32
Fe XI	188.23
Fe XII	195.12
Fe XIII	202.04
Fe XIII	203.83
Fe XV	284.16
Fe XXIV	192.03

Program 1a

Take the highest possible cadence observations in Fe XII 195 in order to use the high
effective area of EIS at this wavelength to search for dynamic coronal phenomena in a
new observation regime (2 sec cadence).

1. Slit: 1"
2. X=1" (no raster)
3. Exposure time: 1 sec
4. Duration: 2 sec
5. Line list: (1 line)
   
   

   Line	Wavelength
   Fe XII	195.12

Program 1b

Use 7 of the strongest EIS lines to search for dynamic phenomena at high cadence. In
particular EIS should allow high cadence density measurements for the first time using
the Fe XIII diagnostic.

1. Slit: 1"
2. X=1" (no raster)
3. Exposure time: 4 sec
4. Duration: 5 sec
5. Line list: (7 lines)
   
   

   Line	Wavelength
   He II	256.32
   Fe XI	188.23
   Fe XII	195.12
   Fe XIII	202.04
   Fe XIII	203.83
   Fe XV	284.16
   Fe XXIV	192.03

Program 1c

A longer exposure time allows a more detailed line list, including lines
from the transition (Fe VIII, Si VII), a complete set of iron lines from
Fe X to Fe XVI, and additional density diagnostics of Fe XII and Fe XIV.

1. Slit: 1"
2. X=1" (no raster)
3. Exposure time: 10 sec
4. Duration: 11 sec
5. Line list: (15 lines) same as Program 1b, plus:
   
   

   Line	Wavelength
   Fe VIII	185.21
   Si VII	275.35
   Fe X	184.54
   Fe XII	186.88
   Fe XIV	264.78
   Fe XIV	274.20
   Fe XVI	263.00
   Ca XVII	192.82

Program 2a

Use a large 256"x256" raster (size of a typical AR) in order to look for
global changes in an active region over several hours.

1. Slit: 1"
2. X=256"; 1" steps
3. Exposure time: 10 sec
4. Duration: 41 min
5. Line list: same as Program 1C

Program 2b

As above, but with a smaller raster in order to take detailed spectra of
dynamic phenomena in the active region.

1. Slit: 1"
2. X=60"; 1" steps
3. Exposure time: 10 sec
4. Duration: 10 min
5. Line list: same as Program 1C

Program 3

A large area, long exposure raster of an active region in order to
measure accurate velocity shifts of emission lines (Å 10,000 counts are
required to obtain velocity shifts accurate to 1 km/s).

1. Slit: 1"
2. X=256"; 1" steps
3. Exposure time: 40 sec
4. Duration: 3 hrs
5. Line list: same as Program 1C

Last Revised: Monday, 24-Jul-2006

Feedback and comments: webmaster