Radiation Spectrometer
Particle Spectrometer for GCR/SPE Characterization
A radiation spectrometer integrates a tissue-equivalent proportional counter and a silicon telescope detector stack to characterize galactic cosmic ray and solar particle event spectra across an energy range of 1 to 1000 MeV. Unshielded by a global magnetosphere, lunar installations face an unfiltered primary particle flux compounded by high-LET secondary neutrons. To calculate accurate, RBE-weighted doses across a 25-year operational lifetime, the 5-kilogram, 10-watt instrument differentiates protons, heavy ions, and electrons while utilizing an onboard alpha calibration source to maintain a linear energy transfer resolution of 1 keV/µm.
Tissue-equivalent proportional counter (TEPC) and silicon telescope characterising GCR/SPE particle spectrum for high-fidelity dose assessment.
Purpose
Tissue-equivalent proportional counter (TEPC) and silicon telescope characterising GCR/SPE particle spectrum for high-fidelity dose assessment.
Context
Child of L2-RAD-MON within the Lunar Ark system
Principles
- ▸TEPC measures linear energy transfer (LET) spectrum
- ▸Silicon telescope identifies proton vs heavy-ion vs electron
- ▸Combined data informs RBE-weighted dose
- ▸Calibration via onboard alpha source
- ▸Long-mission dataset valuable for radiation science
Typical implementations
- ▸Mars Curiosity RAD heritage
- ▸ESA Liulin spectrometer
- ▸JAXA SEDA-AP spectrometer (ISS)
Lunar considerations
- ▸High-LET secondary neutrons RBE underestimated previously (Sen 2024)
- ▸Lunar radiation environment characterised over decades
- ▸Long-life detectors with calibration sources
Specifications
Functional
| primary function | Tissue-equivalent proportional counter (TEPC) and silicon telescope characterising GCR/SPE particle spectrum for high-fidelity dose assessment. |
| energy range mev | 1, 1000 |
| let resolution kev um | 1 |
Physical
| mass kg | 5 |
| materials | TEPC, Si telescope detector stack, Pulse-shape electronics |
| vacuum compatibility | True |
Operational
| power consumption w | 10 |
| thermal range c | -40, 70 |
| lifetime years | 25 |
| mtbf hours | 200000 |
Interfaces
Provides
- Particle spectrum telemetry
- Long-term science archive
Requires
- Spectrometer (~10 W)
Cite this entry
Lunar Ark Codex. "Radiation Spectrometer" (L3-RAD-MON-SPEC). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-RAD-MON-SPEC
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.