Feasibility assessment and applications development of a radiobiological dosimeter for space applications, phase 2

Radiobiological dosimeters were developed and evaluated for space applications. Basic properties and sensitivities of metal oxide semiconductor (MOS) dosimeters were studied and a flexible MOS dosimeter 12 cm long and 3 mm wide was developed for radiobiology experiments. Such a dosimeter could be placed inside biological specimens or incorporated in space suits. A heavy particle detector to detect galactic cosmic rays was also built and tested. The prototype detector consisted of an ion sensitive memory device mounted on a printed circuit board. In space radiation simulations using medical accelerators, the MOS dosimeter was found to have a steady response over the 3 to 17 MeV energy range. A linear response was measured for the flexible MOS dosimeter. Heavy ion experiments were conducted at the Harwell (U.K.) Tandem Generator to test the heavy particle detector. The detector was found to be very sensitive to the high linear energy transfer heavy ions, showing 100 percent efficiency for Cl, Si, and O. Spacebound experiments are being planned in which the dosimeters will be tested on the Mir space station and Biocosmos satellites.