A tissue equivalent proportional counter filled with a mixture of tissue equivalent gas and 3He for neutron monitoring.
Tissue equivalent proportional counters (TEPC) allow the measurement of the ambient dose equivalent H(*)(10) in mixed fields. IRSN has been studying the design and the response of a TEPC in terms of neutron H(*)(10). First, a cylindrical counter was filled with propane gas at a low pressure. H(*)(10) measured in monoenergetic neutron fields underestimated the reference (>50%) at low energies (< 500 keV). A small amount of (3)He was then added to the gas in order to increase the response. The underestimation observed decreased but the results (> 40%) were not totally complying with the objectives (< 20%). Finally the choice was made to improve the analysis of the microdosimetric spectra y.d(y) in order to identify the energy of the incident neutrons. The analysis allows a better estimate of H(*)(10). The aim of this article is to describe the TEPC and the effect of these methods of optimisation.
Chau
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Q
Institute for Radiological Protection and Nuclear Safety, BP 17-92262 Fontenay-aux-Roses, France. quang.chau@irsn.fr
Ménard
S
S
D040761:Biomimetic Materials / Q000737:chemistry* / Q000528:radiation effects*; D001822:Body Burden; D004307:Dose-Response Relationship, Radiation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005740:Gases / Q000737:chemistry*; D006371:Helium / Q000737:chemistry* / Q000528:radiation effects*; D007554:Isotopes / Q000737:chemistry; D009502:Neutrons; D011407:Propane / Q000737:chemistry / Q000528:radiation effects; D011829:Radiation Dosage; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D012062:Relative Biological Effectiveness
D005740:Gases; D007554:Isotopes; D006371:Helium; D011407:Propane