Speaker
Description
As crewed deep-space exploration, including planned missions to the Moon and Mars, continues to advance, the long-term management of astronaut radiation exposure has become a critical issue. In particular, in-situ measurements of protons and heavy ions in the energy range from 15 MeV/n to 2 GeV/n, a range highly relevant to human radiation exposure, remain limited in the space environment. This motivates the development of compact instruments capable of measuring charged particles in this energy band.
Lunar-RICheS is a compact space-radiation spectrometer designed to meet this need. It is being developed through a collaboration among JAXA, RIKEN, and Tokyo University of Science. The instrument consists of a low-energy section based on a stack of silicon detectors and a high-energy section based on a Cherenkov detector. Each section is equipped with an upstream tracker consisting of two double-sided silicon strip detectors (DSSDs), which measure the trajectories of incident charged particles. In the high-energy section, the reconstructed particle trajectory is essential for analyzing the Cherenkov ring pattern.
We constructed a prototype DSSD tracking system and evaluated its performance using cosmic-ray muons. After establishing an alignment procedure to correct relative misalignments between detector planes, we evaluated both the intrinsic position resolution of the DSSDs and the track-extrapolation accuracy. The results demonstrate that the tracker achieves the position accuracy required for Lunar-RICheS.
In this contribution, we present the current status of Lunar-RICheS together with the analysis methods and results of the performance evaluation of the DSSD tracker.