1. Geant4 Context from the point of view of The Space Environments and Effects Analysis Section
E.J. Daly

2. ESA Programmes http://www.esa.int/ Science (~14%)
Applications missions : Navigation (growing) Earth Observation (weather, etc.); Telecomms.
Manned Missions (International Space Station)
Launchers
R&D

3. Budgets (‘97) Earth Observation 24%; 632M Ecu Science 14%; 352M Ecu
General &… 10%; 270M Ecu
Telecomms 6.4%; 165M Ecu
Launchers 22%; 574M Ecu
Manned & microgravity 17% 466M Ecu

4. Astrophysics missions

5. Trends More demanding science missions
More sensitive components (“payloads” & “platforms”)
COTS (Commercial Off The Shelf) components
“Cheaper-faster-better”; “smaller-faster-cheaper”, etc…
man in space: career astronauts; long stays
{Avionics and air crew}
Operations in the “space radiation environment”

6. The Radiation Environment
Galactic Cosmic Rays
The Radiation Environment
Radiation Belts
Solar Energetic Particles

7. Space Weather "conditions on the sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can influence the performance and reliability of space-borne and ground-based technological systems and can endanger human life or health”

8. Effects on Space Systems: Radiation

9. Solar Energetic Events & Effects
SOHO
LASCO
Flare on sun
SOHO EIT
Coronal Mass Ejection
Sun’s disk
Cosmic-ray strikes on CCD

10. Solar Energetic Events & Effects

11. Solar Energetic Events & Effects
Solar energetic particles hit detectors

12. Equator-S Failure Back-up CPU Fails Enhanced Hot Electrons December 97
Primary CPU Fails
April 98
GOES Energetic Particle Data Courtesy NOAA

13. Geo- stationary Altitude
High
Colour-coded Dose Rate from REM on STRV in GTO
1994
1995
1996
1997
1998
Geo- stationary Altitude
Dose
Low
Outer Belt 4
Radial Distance (RE)
“Slot”
Earth’s Surface
Inner Belt

14. Hipparcos Radiation Background
Radial
geocentric
distance
Dec 89 - Feb 93
Apr. ‘90
Mar. ‘91
Nov. ‘91
May ‘92
GEO orbit
altitude
Earth’s surface

15. UoSAT SEU’s
mapped
Oct ‘89
Time behaviour

16. South Atlantic Anomaly
SEU:

17. Systems Becoming More Sensitive
Outlook
Need for tools
Demanding missions
- Science: Cluster-II, XMM, Integral, Rosetta, SMART-1, Mars Express…
- Applications: - telecom [incl. Artemis], constellations, navigation, EO [incl. Envisat]
- Space Station
New and old problems
More types of SEU’s
Radiation Background
Surface and internal charging
Solar array problems, …
Systems Becoming More Sensitive
- sensitive payloads
- high-performance components
- more and longer manned missions
- lightweight, low-cost

18. The Current Challenge Typical Focal Plane of an X-ray mission
A “typical” X-ray telescope
Typical Focal Plane of an X-ray mission

19. What can affect CCD’s on X-ray astronomy missions?
Radiation belt electrons?
Scattered in the mirror shells?
Effectiveness of Magnetic “brooms”
Electron damage mechanism? - NIEL?
Other particles? Protons, cosmics
path to CCD? wall penetration?
Proposal: set the problem up in Geant4 as a case-study for the week.