Benchmarking Space Radiation Transport Codes Using Measured LET Spectra from the Crater Instrument on LRO

Lawrence W Townsend1, Jamie Porter1, Harlan E Spence2, Michael Joseph Golightly3, Sonya S Smith4, Nathan Schwadron5, Justin Christophe Kasper6, Anthony W Case7, J Bernard Blake8, Joseph E Mazur9, Mark Dixon Looper10 and Cary J Zeitlin11, (1)University of Tennessee Knoxville, Knoxville, TN, United States, (2)University of New Hampshire Main Campus, Space Science Center, Durham, NH, United States, (3)Assurance Technology Corporation, Carlisle, MA, United States, (4)University of New Hampshire, Durham, United States, (5)Los Alamos National Laboratory, Los Alamos, United States, (6)University of Michigan, Climate and Space Sciences and Engineering, Ann Arbor, United States, (7)Smithsonian Astrophysical Observatory, Cambridge, MA, United States, (8)The Aerospace Corporation, Space Sciences Department, El Segundo, CA, United States, (9)The Aerospace Corporation, Chantilly, VA, United States, (10)The Aerospace Corp, Los Angeles, United States, (11)Southwest Research Institute, Oakland, CA, United States
Abstract:
The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument on the Lunar Reconnaissance Orbiter (LRO) spacecraft measures the energy depositions by solar and galactic cosmic radiations in its silicon detectors. These energy depositions are converted to linear energy transfer (LET) spectra, which can contribute to benchmarking space radiation transport codes and also used to estimate doses for the Lunar environment. In this work the Monte Carlo transport code HETC-HEDS (High Energy Transport Code – Human Exploration and Development in Space) and the deterministic NASA space radiation transport code HZETRN2010 are used to estimate LET and dose contributions from the incident primary ions and their charged secondaries produced in nuclear collisions within the components of the CRaTER instrument. Comparisons of the calculated LET spectra with measurements of LET from the CRaTER instrument are made and clearly show the importance of including corrections to the calculated average energy deposition spectra in the silicon detectors using a Vavilov distribution function.
Back to: Ionizing Radiation Environments throughout the Solar System II