Flight prototype of a solid state neutron dosimeter for space applications

A major impediment to the accurate measurement of neutron dose experienced by astronauts arises from the sensitivity of most neutron dosimeters to the large fluxes of protons which occur during a typical space mission. As a result, measurement of the neutron dose has remained largely an unsolved problem. Under NASA sponsorship, we have developed a special PIN diode that has good response to neutrons while being relatively insensitive to other forms of ionizing radiation. This new sensor has been incorporated into a very compact flight instrument to provide high quality real time measurement of neutron dose. The dosimeter is capable of measuring and periodically recording fast neutron dose (E_n⩾140 keV) from 50 microgray to tens of milligrays (5 mRads to several Rads) over a flight of up to 14 days with an accuracy of ±17.5 micrograys (±1.75 mRads) or better. The latest measurements of the PIN diode performance, with a detailed description of the overall instrument, are presented