Substorm Associated Spikes in HighEnergy Particle Precipitation

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GloRiA
The Global Riometer Array
Farideh Honary, Andrew Kavanagh, Eric Donovan,
Emma Spanswick,, Steve Marple, and Arne Aasnes
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GloRiA
The Global Riometer Array
The objective of GloRiA is to combine riometer
data sets from around the world creating a
virtual array which can produce images of
high-energy electron precipitation on a global
scale.
GloRiA incorporates riometer data from programs
in the UK, Finland, Canada, US, Germany, Denmark,
Japan, Russia, Australia, South Africa, Italy,
Norway and China.
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GloRiA
The Global Riometer Array
The objective of GloRiA is to combine riometer
data sets from around the world creating a
virtual array which can produce images of
high-energy electron precipitation on a global
scale.
A virtual observatory (GAIA) is being developed
for easy access to summary optical and riometer
data. The first stage went online in September
2005.
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Global Auroral Imaging Access
http//gaia-vxo.org
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High-Energy Particles Sources
High-Energy Particle Measurements
(gt10keV)
In situ
Particle detectors (LANL, GOES, CRRES,
etc.) X-Ray Imagers (PIXIE)
Remote Space
Remote Ground-Based
Riometers (NORSTAR, SGO, IRIS, etc.)
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High-Energy Particles Sources
High-Energy Particle Measurements
(gt10keV)
In situ
Particle detectors (LANL, GOES, CRRES,
etc.) X-Ray Imagers (PIXIE)
Remote Space
Remote Ground-Based
Riometers (NORSTAR, SGO, IRIS, etc.)
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Riometer Measurements
Riometer Absorption
Baker et al. 1981
gt30 keV Electron Flux (geosynchronous)

• nearly continuously correlated data sets
  (riometer and geostationary electron
  measurements)

Remote sensing magnetospheric high-energy
electrons one objective of what we are doing
others are high-energy solar protons, structured
higher-energy aurora, etc.
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GloRiA
The Global Riometer Array
Global images that are very coarse grained
spatially, but with high time resolution,
continuous coverage, and in regions very high
spatial resolution.
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GloRiA
GloRiA Scientific objectives are

• Understand mesospheric chemistry changes due to
  energetic particle precipitation and X-ray
  flares.
• Investigate the role of energetic particle
  precipitation on the global atmospheric
  electrical circuit.
• Determine energy deposition into the mesosphere
  via energetic particles and their modulation by
  ULF waves on global scales.
• Investigate the role of energetic solar particles
  in stratospheric/mesospheric ozone destruction.
• Provide a direct measure of the morphology of
  precipitation
• Monitoring absorption drifts.
• Producing large scale maps of absorption
  including Inter-hemispheric and day/night side
  examination of precipitation.

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Riometer Measurements
Scale Sizes
The high-energy electron and proton precipitation
is organized on local and global scales and over
short and longer time scales.
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Riometer Measurements
Scale Sizes
For example - PCA during the Bastille Day
Storm. Data provided by Gloria members CANOPAS
(NORSTAR), SGO, Univ.of Maryland and Lancaster
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Riometer Measurements
Scale Sizes
For example the substorm onset CNA spike that
is possibly the fastest substorm onset signature
(Spanswick et al., 2005).
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Scale Sizes
For example the global evolution of the
injection.
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Substorm Injections
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Substorm Injections
Drifting Electron Clouds
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Conclusions

• GloRiA is an attempt to organize riometer
  observations and data to provide researchers with
  ready access to truly global network.
• We are currently working primarily with data from
  Finland and Canada, however GloRiA will involve
  instruments operated by numerous other countries
  in both hemispheres.
• In September 2005 an initial phase virtual
  observatory (GAIA) went online providing access
  to summary data from some GloRiA stations.
• There are a number of studies currently underway
  (substorm spikes, dispersionless injections,
  sawtooth events, ULF precipitation, etc) wherein
  we are doing new science with data from this
  useful instrument.