Radiation and Fault Tolerance for Neuromorphic Computing

• The solar wind emanating from the sun is a stream of energetic electrons and protons and ions that are the primary ionizing radiation contributions.

• The Earth’s magnetosphere significantly reduces radiation exposure and mutes the effects of solar flares out to 65K Km orbital altitude.

• The radiation environment is highly dependent upon mission profile: for example geosynchronous orbits can see 50 times the radiation dose of a polar orbit due to reduction of
atmospheric/magnetospheric shielding.

• In LEO, the magnetosphere shields the Earth by creating trapped Van Allen radiation belts consisting of electrons and protons, which create a challenging radiation environment confined to specific regions.

• Even for LEO, radiation dose can vary by a factor of 30 or more from a quiet sun to a solar flare.

• Galactic Cosmic Rays (GCRs) are also present at very high energy, but at low rates.

• Radiation effects on semiconductors are highly dependent upon particles species, energy and
flux.

• Therefore, radiation tolerance requirements will vary with mission profile and duration.