Analyses of Measurements from the CRaTER Instrument on the LRO Spacecraft using Space Radiation Transport Codes

In June 2009, the Lunar Reconnaissance Orbital (LRO) Spacecraft was launched to orbit Earth’s Moon. Objectives of this mission are to find potential safe landing sites, locate potential resources, test new technologies, and characterize the lunar radiation environment. Located on the LRO is the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument which is designed to characterize the lunar radiation environment, its biological impact on humans, and impact on equipment. CRaTER will provide a better and more accurate understanding of the lunar radiation environment by measuring linear energy transfer (LET). This lunar environment includes solar particle events (SPEs) and high energy galactic cosmic rays (GCRs). To predict and support CRaTER’s observed data, a comparison to benchmarked radiation transport codes is necessary. The goal of this dissertation is to compare CRaTER’s observed data to simulated results from the Monte Carlo code, High Energy Transport Code – Human Exploration and Development in Space (HETC-HEDS) and the deterministic code, High-Charge-and-Energy Transport (HZETRN). A central part of these analyses is separating the contributions of secondary particles, produced by nuclear interactions in the instrument, from the contributions of these incident primary ions. Also included is a simple analysis of the effects of escaping delta rays on the instrument output spectra.