Monitoring Cosmic Radiation Risk: Comparisons between Observations and Predictive Codes for Naval Aviation

Abstract : Utilizing a unique, Far West Technology Tissue Equivalent Proportional Counter (TEPC)-based system called the HAWK, the atmospheric radiation exposures of commercial air travelers and naval personnel were compared to the quantity predicted by commercially available radiation codes. The HAWK simulates a two micron-diameter somatic cell, measuring the lineal energy, absorbed dose, and dose equivalent based on the International Commission on Radiological Protection (ICRP)-60 recommendations. Prior to the flights, the HAWK detector response was modeled with MCNP5 and GEANT4. Later, the data were analyzed both to produce a dose rate as well as a total dose for the flight's duration. Over 40 hours of flight data was obtained on commercial aircraft in addition to several experiments on military and private aircraft. Flights were conducted across the continental United States, from Massachusetts to California. The military flights were conducted on an EA-6B Prowler from the Navy's VX-23 Squadron in Patuxent River, Maryland. Commercial aircraft altitudes reached a ceiling of approximately 38,000 feet while typical military operations were around 25,000 feet. During the flight, data including dose and dose equivalent rates were collected along with corresponding GPS data such as geodetic latitude, longitude, and altitude. The GPS data were then utilized as inputs for several commercially available radiation codes for assessing atmospheric radiation risk.