Radiation Dosimetry Experiment (RaD-X): High-Altitude Balloon Flight Mission for Improving the Nairas Aviation Radiation Model

Abstract:

The NASA Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model is a real-time, global, physics-based model for predicting exposure to cosmic radiation to air travelers from both galactic and solar sources. Tabular and graphical data products from the prototype operational NAIRAS model have been available to the public since April 2011. An initial validation of the NAIRAS model was recently conducted by comparing predicted dose rates with tabulated reference aircraft measurement data and recent aircraft radiation measurements taken in 2008. However, aircraft measurements alone do not provide an unambiguous constraint on the model such that the predominant source of uncertainty in the NAIRAS model could be uniquely identified. High altitude measurements above the Pfotzer maximum are needed to characterize the extent to which the NAIRAS model can predict the cosmic radiation primaries, which are the source of the secondary particles that are responsible for radiation exposure at aircraft flight altitudes. The Radiation Dosimetry Experiment (RaD-X) is a NASA high-altitude balloon flight mission with the goal of improving model characterization of cosmic radiation primaries by taking dosimetric measurements above the Pfotzer maximum. A second goal of the RaD-X mission is to facilitate the pathway toward data assimilative predictions of atmospheric cosmic radiation exposure by identifying and characterizing low-cost radiation measurement solutions. RaD-X is scheduled for launch at Fort Sumner, NM in September 2015. Here we briefly describe the NAIRAS model, present the science and mission overview of the RaD-X mission, and show preliminary results from instrument beam tests and calibration.