ONE OF THE MOST SIGNIFICANT CHALLENGES FACED WHEN CONSIDERING HUMAN OPERATIONS IN OUTER SPACE IS QUANTIFYING THE BIOLOGICAL RISK ASSOCIATED WITH THE SPACE RADIATION ENVIRONMENT. RADIATION TRANSPORT CODES ARE ONE OF THE TOOLS NECESSARY TO DETERMINE THIS RISK. THESE TRANSPORT CALCULATIONS DESCRIBE THE COUPLED PHENOMENA OF HOW A GIVEN RADIATION FIELD CHANGES AS IT MOVES THROUGH MATTER AND HOW THE MATTER IS PHYSICALLY AFFECTED BY THE PRESENCE OF THE RADIATION. NASA S DETERMINISTIC HIGH ENERGY AND HEAVY CHARGED PARTICLE TRANSPORT CODE HZETRN IS DEVELOPED AND MAINTAINED AT THE LANGLEY RESEARCH CENTER. DUE TO THE NATURE OF THE SPACE RADIATION ENVIRONMENT IT IS OF IMPORTANCE THAT THESE TRANSPORT CODES ARE ABLE TO DESCRIBE THE BREAKUP OF HEAVY IONS INTO SMALLER FRAGMENTS LIGHT IONS IN PARTICULAR AS THEY ARE MORE BIOLOGICALLY SIGNIFICANT. FOR THIS EVENT GENERATORS WITHIN RADIATION TRANSPORT CODES RELY ON NUCLEAR FRAGMENTATION CROSS SECTION MODELING CODES TO PREDICT THE PRODUCTS OF HIGH ENERGY NUCLEAR COLLISIONS. IN RECENT YEARS THE RELATIVISTIC ABRASION-ABLATION AND DEEXCITATION FRAGMENTATION MODEL RAADFRG HAS BEEN DEVELOPED IN A COLLABORATIVE EFFORT BETWEEN THE UNIVERSITY OF TENNESSEE AND THE NASA LANGLEY RESEARCH CENTER. INTEGRATING RAADFRG INTO THE HZETRN CODE WILL ENHANCE THE TRANSPORT CODE S ABILITY TO DESCRIBE SECONDARY PARTICLE PRODUCTION INCLUDING LIGHT ION PRODUCTION. THE INTEGRATION PROCESS BEGINS WITH A COMPREHENSIVE EVALUATION OF THE RAADFRG CODE S PERFORMANCE AGAINST A DATABASE OF MEASURED CROSS SECTIONS INCLUDING ANY MODIFICATIONS TO THE INTERNAL PHYSICS ROUTINES WITHIN THE MODEL IF WARRANTED. UPON COMPLETION OF THE PERFORMANCE EVALUATION THE FRAMEWORK COUPLING THE RAADFRG MODEL AND THE HZETRN CODE WILL BE DEVELOPED AND IMPLEMENTED. THE RESULTING CODE WILL BE VALIDATED AND BENCHMARKED. SUBSEQUENTLY FINAL PACKAGING OF THE RAADFRG-COUPLED VERSION OF THE HZETRN WILL BE ASSEMBLED INCLUDING DOCUMENTATION.

University System Of New Hampshire

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