Monte Carlo Simulations of Energy Losses by Space Protons in the CRaTER Detector
- Paper number
IAC-08.A1.4.6
- Author
Dr. Lawrence W. Townsend, The University of Tennessee, United States
- Coauthor
Dr. Hanna Moussa, The University of Tennessee, United States
- Coauthor
Mr. Youssef Charara, The University of Tennessee, United States
- Year
2008
- Abstract
The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) detector is designed to be carried on the Lunar Reconnaissance Orbiter (LRO) spacecraft, which scheduled for launch by the fall of 2008. The spacecraft will orbit the Moon in a polar orbit, at an altitude of 50 km, for a planned one year mission. In lunar orbit, CRaTER will be used to characterize the lunar radiation environment and its biological impacts on humans. Other LRO objectives include: (1) developing a high-resolution global, three-dimensional geodetic grid of the Moon and provide the topography necessary for selecting future landing sites; (2) assessing in detail the resources and environments of the Moon’s polar regions; and (3) conducting a high spatial resolution assessment of the Moon’s surface addressing elemental composition, mineralogy, and regolith characteristics.
The aim of the present work is to estimate the energy lost and the linear energy transfer (LET) in CRaTER from energetic protons, such as those found in solar energetic particle events and galactic cosmic ray environments. Simulations of detector responses to protons with energies between 300 MeV and 2 GeV are made using the recently-modified HETC-HEDS (High Energy Transport Code – Human Exploration and Development of Space) Monte Carlo radiation transport code. This work constitutes part of the characterization of the CRaTER detector. Calibration of the detector has been carried out using proton beams from the cyclotron at Massachusetts General Hospital, beams of protons and heavy ions from the LBNL 88" cyclotron, and Fe beams obtained at the NASA Space Radiation Laboratory (NSRL) at BNL. Simulations of these calibration runs are underway, as are data analyses from the calibration runs themselves. As a check on the validity of the results obtained from HETC-HEDS, energy loss and LET spectra for protons at incident energies of 300, 600 and 1000 MeV are obtained using the Monte Carlo Code System for Multiparticle and High Energy Applications (MCNPX) and compared with the HETC-HEDS predictions. In this work we briefly describe the CRaTER detector configuration. We then present the calculated energy losses and the LET in the two different volumes of tissue equivalent plastic detectors (TEP), within the CRaTER detector. Agreement between the code predictions for a variety of proton energies between 300 and 2000 MeV is found to be within approximately 10%.
- Abstract document
- Manuscript document
IAC-08.A1.4.6.pdf (🔒 authorized access only).
To get the manuscript, please contact IAF Secretariat.