Experimental study of neutron response of a moderated superheated drop detector

Conference · Mon Dec 31 23:00:00 EST 1990 · Transactions of the American Nuclear Society; (United States)

OSTI ID:7015873

Wang, C K ^[1]

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1. Kansas State Univ., Manhattan (United States)

A neutron dosimeter using superheated drops in a gel matrix was invented by Apfel. Similar products using superheated drops in firm polymer have also been developed. The SDD-100 or BD-100, which uses Freon-12 for the superheated drops, is the most widely used neutron dosimeter because it was claimed that the neutron response function of such a dosimeter is nearly dose equivalent; i.e., the number of bubbles generated by an SDD-100 or a BD-100 after exposure with neutrons is directly proportional to the dose equivalent (e.g., {mu}Sv). An ideal dose-equivalent neutron dosimeter should be totally independent of the energies of incident neutrons. Detailed Monte Carlo calculations, however, revealed that the bare SDD-100 favorably responds to thermal neutrons and neutrons with energies between 70 and 700 keV; it does not respond as well to several-mega-electron-volt neutrons, and it poorly responds to neutrons with energies between 10 eV and 50 keV. It was also known that with additional polyethylene wrapped around it, the response of an SDD-100 to neutrons becomes considerably more dose equivalent. This is because the incoming neutrons with energies between 10 eV and 50 keV will first slow down or thermalize in the polyethylene and then reach the SDD-100 and trigger bubbles via the {sup 35}Cl(n,p){sup 35}S reactions. The optimum thickness of the polyethylene was judged to be 2.54 cm{sup 3}.

• OSTI ID: 7015873
• Report Number(s): CONF-911107--
• Journal Information: Transactions of the American Nuclear Society; (United States), Journal Name: Transactions of the American Nuclear Society; (United States) Vol. 63; ISSN TANSA; ISSN 0003-018X
• Country of Publication: United States
• Language: English

Related Subjects

440102* -- Radiation Instrumentation-- Radiation Dosemeters
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTINIDES
ALKALINE EARTH METALS
ALPHA DECAY RADIOISOTOPES
BARYONS
BEAMS
BERYLLIUM
BUBBLES
CALIFORNIUM 252
CALIFORNIUM ISOTOPES
COMPUTER CODES
DECAY
DOSE EQUIVALENTS
DOSES
DOSIMETRY
DROPLETS
EFFICIENCY
ELEMENTARY PARTICLES
ELEMENTS
ENRICHED URANIUM REACTORS
EVEN-EVEN NUCLEI
FERMIONS
FISSION
FREONS
FUNCTIONS
HADRONS
HALOGENATED ALIPHATIC HYDROCARBONS
HEATING
HEAVY NUCLEI
HEAVY WATER
HOMOGENEOUS REACTORS
HYDRIDE MODERATED REACTORS
HYDROGEN COMPOUNDS
IRRADIATION REACTORS
ISOTOPE PRODUCTION REACTORS
ISOTOPES
MEASURING INSTRUMENTS
METALS
MODERATORS
MONITORS
MONTE CARLO METHOD
NEUTRON BEAMS
NEUTRON FLUX
NEUTRON MONITORS
NEUTRON SOURCES
NEUTRON SPECTRA
NEUTRONS
NUCLEAR DECAY
NUCLEAR REACTIONS
NUCLEI
NUCLEON BEAMS
NUCLEONS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
OXYGEN COMPOUNDS
PARTICLE BEAMS
PARTICLE SOURCES
PARTICLES
PLUTONIUM
POLYETHYLENES
POLYMERS
POLYOLEFINS
PULSED REACTORS
RADIATION DOSES
RADIATION FLUX
RADIATION MONITORS
RADIATION SOURCES
RADIOISOTOPES
REACTORS
RESEARCH AND TEST REACTORS
RESPONSE FUNCTIONS
S CODES
SOLID HOMOGENEOUS REACTORS
SPECTRA
SPONTANEOUS FISSION
SPONTANEOUS FISSION RADIOISOTOPES
SUPERHEATING
THERMAL NEUTRONS
THERMAL REACTORS
TRANSURANIUM ELEMENTS
TRIGA TYPE REACTORS
TRIGA-2-KANSAS REACTOR
WATER
WATER COOLED REAC
YEARS LIVING RADIOISOTOPES