Abstract
In March 2016 accelerator-based experiments colliding protons (0.4 and 0.8 GeV), helium (0.4 AGeV) and iron (0.4 and 0.8 AGeV) on thick aluminum targets with surface densities of 20, 40, and 60 g/cm2 were performed at the National Aeronautics and Space Administration Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory. Two targets were utilized in each experimental configuration. Hydrogen and helium ions were detected using organic liquid scintillators in conjunction with thin plastic scintillators at 10°, 30°, 45°, 60°, 80°, and 135° from beam axis. Time-of-flight techniques and pulse shape discrimination were used to identify light ion species in order to generate double differential energy spectra of the light ion fragments. Comparisons of these measured yields were compared with Monte Carlo calculations generated by MCNP6. These yields will be used to quantify uncertainty in radiation transport codes utilized in risk assessment for spaceflight missions with prolonged exposures to galactic cosmic rays.
Highlights
The radiation environment beyond the confines of Earth’s magnetosphere poses a significant risk for future manned missions
Current calculations of Radiation Exposure Induced Death (REID) suggest that increased shielding has a negligible ability to reduce cancer risks [1]. These estimates of risk are based on particle fluences simulated by deterministic radiation transport codes, which are verified and validated by fits to measurements of Galactic Cosmic Ray (GCR) ion fluences from probes in Earth’s atmosphere
The purpose of the experiment is to provide measurements of double differential light ions yields through thick targets composed of materials commonly selected to shield against GCR
Summary
The radiation environment beyond the confines of Earth’s magnetosphere poses a significant risk for future manned missions. These estimates of risk are based on particle fluences simulated by deterministic radiation transport codes, which are verified and validated by fits to measurements of GCR ion fluences from probes in Earth’s atmosphere. The limitations of the available data increase the uncertainties associated with transport calculations and subsequent risk assessments from GCR ions at higher energies.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have