OBTAINING A SYSTEM OF DOSIMETRY. Report No. 14 (Final) for Period September 28, 1956 to March 31, 1959

Technical Report · Mon Mar 16 04:00:00 EST 1959

OSTI ID:4241411

Taimuty, S I

Progress is reported in the development of dosimetry systems for use with electron beams and gamma sources during the irradiation of foods and food products. The dose range to be measured is from 10/sup 4/ to 10/sup 7/ rads at dose rates up to 5 x 10/sup 8/ rads/min. A literature survey was made and 18 integrating dosimeters were chosen for experimental evaluation. Included were four aqueous solutions, four luminescent solids, four glasses, two plastics, nitrous oxide gas, cyclohexane gas evolution, and acid production by chlorinated hydrocarbons. The performance of these dosimeters was rated against the desirable requirements. Only four of the dosimeters came close to meeting the requirements. Cobalt glass and ceric sulfate aqueous solution dosimeters were selected for further development. Continuous beam current and beam energy monitors were developed for use with electron accelerators. One of the current monitors is based on measurement of low energy secondary electrons emitted from the surface of a metallic foil in vacuo through which the total beam is transmitted. The device provides a linear response independent of energy over a wide range. Two energy monitoring techniques were developed based on measurements of beam intensity as a function of depth in irradiated materials. One technique utilizes a stack of aluminum foils or plates, each of which is insulated from its neighbors. The second technique involves the use of small secondary emission chambers, imbedded at various depths in waterfilled chambers, to monitor intensity as a function of depth. The continuous gamma source monitor consists of a spherical graphite cavity ionization chamber designed for satisfactory operation at dose rates as high as 107 rads/hr. (C.H.)

• Research Organization: Stanford Research Inst., Menlo Park, Calif.
• NSA Number: NSA-13-015274
• OSTI ID: 4241411
• Report Number(s): NP-7613
• Country of Publication: United States
• Language: English

Related Subjects

ACCELERATORS
ACIDS
ALUMINUM
CERIUM SULFATES
COBALT
CURRENTS
DIELECTRICS
DOSEMETERS
ELECTRON BEAMS
FOILS
FOOD
GAMMA RADIATION
GASES
GLASS
HEXANE
INSTRUMENTS
IONIZATION CHAMBERS
IRRADIATION
LUMINESCENCE
METALS
MONITORING
NITROGEN COMPOUNDS
ORGANIC CHLORINE COMPOUNDS
OXIDES
PERFORMANCE
POLYMERS
RADIATION DOSES
SOLIDS
SOLUTIONS
WATER