A Simplified Apparatus for Short-Term Irradiations at 77°K

A simplified inexpensive apparatus was devised to irradiate specimens at liquid nitrogen temperatures (∼77°K) in a Dewar system. Provisions were also made to maintain the specimen at LN₂ temperatures after irradiation for low temperature testing. Using the PSTR at a power level of 1 MW, a specimen can receive 10¹⁴ to 10¹⁵ n/cm² integrated fast flux during an irradiation where the Dewar system is filled once. In addition to being inexpensive, the irradiation technique tends to minimize dangers resulting from possible explosions.