EIS Science Goals: The First Three Months'

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EIS Science Goals The First Three Months.

• Louise Harra
• Mullard Space Science Laboratory
• University College London

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SCIENCE GOALS

• Coronal heating - to determine the physical
  mechanisms responsible for coronal heating in the
  quiet Sun and active regions (e.g. detect
  magnetic reconnection, wave heating).
• Transient Phenomena - to determine the physical
  mechanisms responsible for transient phenomena,
  such as solar flares, coronal mass ejections,
  jets, network brightenings (e.g. determine energy
  transport and mass motions during transient
  events).
• Energy Transfer from the photosphere to the
  corona -to investigate the causal relationship
  between dynamics in the photosphere and coronal
  phenomena.

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Extreme-Ultraviolet Imaging Spectrometer (EIS)

• EIS Records Solar Extreme-Ultraviolet (EUV)
  Spectra That Contain Information on the Dynamics,
  Velocity, Temperature, and Density of the
  Emitting Plasma
• Spectra Are Obtained With High Spatial Resolution
• Spectra at Many Locations Within an Entire Solar
  Structure Can Be Recorded
• Spectra Are Obtained With Sufficient Time
  Resolution to Determine the Dynamics As a
  Function of Position Within Solar Flare and
  Active Region Loops
• EIS Is the First EUV Solar Spectrometer Capable
  of Obtaining High Spectral Resolution Data With
  Both High Spatial and Temporal Resolution

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EIS Science Planning Guide

• We are developing this on our web site
  www.mssl.ucl.ac.uk/espg.html
• Includes an EIS study form in order to play
  with your own personal observing plans.
• Includes a list of EIS studies produced by the
  EIS team
• Includes line lists and intensities in different
  regions of activity
• Includes a set of science data products
• Includes an initial science plan for the first 3
  months

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The first 3 months.

• Flare trigger and dynamics the first spatial
  determination of evaporation and turbulence in a
  flare
• Active region heatingthe first spatial
  determination of the velocity field in active
  region loops
• Coronal Mass Ejection Onsetfirst spatial
  velocity and dimming measurement at high temporal
  resolution
• Coronal Hole Boundariesthe first measurement of
  intensity and velocity field at the coronal hole
  boundary
• Quiet Sun Brighteningsfirst determination of the
  relationship between different categories of
  quiet Sun events.

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Flare Trigger/Dynamics
Evaporation - We know its happening, but where
from and what size?
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Flare Trigger/Dynamics
Inflow weve seen it once! But is it happening
all the time?
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Flare Trigger/Dynamics
What causes a flare? We have many
tantalizing hints - EIS will provide spatial
resolved preflare Vnt flow measurements.
TRACE 1600 CDS OV
TRACE 195 RHESSI 6-12keV
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Active Region Heating
What causes loop heating and dynamics? Accurate
line width and Doppler velocity measurements
over a range of velocities will provide critical
information.
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Coronal Mass Ejection Onset
We need to know the velocity and dimming profiles
over a range of temperatures to begin
to understand the CME onset (see Harra
Sterling, 2001)
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Coronal Mass Ejection Onset
Coronal waves are often seen related to CMEs
- what are the physical characteristics of these
waves?
CDS data is showing some tantalizing hints. See
Harra Sterling 2003
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Coronal Hole Boundaries
The CH boundaries are not well understood -
we will be able to determine the velocity field
at this important region.
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Quiet Sun Events
Are explosive events and blinkers the same
phenomena? We will be able to measure velocities
at good spatial resolution.
OV
45,000km
7,500 km
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Conclusions

• I have concentrated on what EIS can do for us in
  the first few months - combining these
  observations with SOT and XRT will provide new
  and exciting science.
• We intend to track targets for long periods of
  time (at least a day on each target).
• If there is an active region we will track it. If
  not we will carry out the CME onset on filaments,
  QS and CH studies.