Accession Number : AD0433633

Title :   PROTOTYPE OF A PORTABLE MICROCALORIMETER FOR MEASUREMENT OF ABSORBED DOSE,

Corporate Author : NAVAL RADIOLOGICAL DEFENSE LAB SAN FRANCISCO CA

Personal Author(s) : Schleiger, E. R. ; Goldstein, N.

Report Date : 06 JAN 1964

Pagination or Media Count : 20

Abstract : A prototype of a compact, portable microcalorimeter was built which measures ionizing radiation dose rates as low as 3 aluminum rads/min. The absorber and temperature sensing system are similar to those described in USNRDL-TR621, but the temperature controlled bath described therein has been replaced by an aluminum isothermal shield bolted to the bottom surface of a copper reservoir containing liquid nitrogen. Both the shield and the reservoir are contained in a vacuum chamber. Calibration of the absorber is accomplished by observing the response of an imbedded thermistor when the calorimeter is placed in a gamma-ray field of known exposure level provided by a 200-curie Co60 source. Plans are presented for extending this method of temperature control to a smaller microcalorimeter (outside diameter 2.25 in.) which will increase the portability and minimize attenuation of the radiation field. (Author)

Descriptors :   *CALORIMETERS, *RADIATION MEASURING INSTRUMENTS, DOSAGE, TEMPERATURE, ABSORPTION, CALIBRATION, THERMISTORS, DOSE RATE, SENSITIVITY, STABILITY.

Distribution Statement : APPROVED FOR PUBLIC RELEASE