Space Radiation Environment P. Nieminen, ESA/ESTEC, The Netherlands

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Space Radiation Environment P. Nieminen,
ESA/ESTEC, The Netherlands

• Overview
• Solar cosmic rays
• Trapped particles in the Earths magnetosphere
• Cosmic Rays
• Other sources
• SREM on ESA missions
• Conclusions

ESA Space Environment Effects Analysis Section
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Anomalous cosmic rays
Galactic and extra-galactic cosmic rays
Jovian electrons
Neutrinos
Solar X-rays
Trapped particles
Induced emission
Solar flare neutrons and g-rays
Solar flare electrons, protons, and heavy ions
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Solar cycles
Sunspot number from 1750
Yohkoh SXT 1991 and 1995
ESA Space Environment Effects Analysis Section
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Solar proton/ion events
SOHO EIT
New Mexico Ha image
Proton event on 20-23 April -98 ISO Star
Tracker fake counts
ESA Space Environment Effects Analysis Section
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SOHO LASCO instrument before the event...
and after.
ESA Space Environment Effects Analysis Section
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Trapped particles
The SAA
ESA Space Environment Effects Analysis Section
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Trapped particles
Electron spectra
Proton spectra
REM data
ESA Space Environment Effects Analysis Section
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Cosmic rays
Peak at 500 MeV
In space, long-term data from various missions
On ground, terrestrial source (cosmic ray
showers) Neutron monitor network
Anomalous CR
High-energy tail up to 1022 eV
ESA Space Environment Effects Analysis Section
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Exotic sources
Jovian electrons from Mercury to outer Solar
System
Knee at 20 MeV
Solar neutrons (at 1 AU 10 MeV and above)
ESA Space Environment Effects Analysis Section
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Standard Radiation Environment Monitor (SREM)
Aluminum
Tantalum
Silicon (detectors)
e-
Trade-off- Performance- Cost- Mass-
Volume
e-
(p)
D1
D2
Optimised Al-Ta Sandwich structure.
Simulation outcome modularity (D3)
- Electrons gt 0.5 MeV- Protons gt 10 MeV- Heavy
ions qualitatively
ESA Space Environment Effects Analysis Section
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Missions with SREM...
ESA Space Environment Effects Analysis Section
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Conclusions

• Space radiation environment highly complex and
  dynamic

• From DNA damage point of view, heavy ions have
  priority however other sources secondary
  emissions also need to be considered

• ESA-sponsored work on several space-specific
  modules completed or underway the toolkit has
  the required basic capabilities

ESA Space Environment Effects Analysis Section