Electrical breakdown and optical emission properties of high pressure pulsed RF gas discharges

Conference · Wed Jun 01 00:00:00 EDT 1994

OSTI ID:10156829

Hunter, S R; Hurst, G S ^[1]; Gibson, W A ^[1]; Turner, J E; Hamm, R N ^[2]; Wright, H A ^[3]

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1. Pellissippi International, Oak Ridge, TN (United States)
2. Oak Ridge National Lab., TN (United States)
3. Consultec Scientific, Inc., Knoxville, TN (United States)

A fundamentally new technique for the measurement of the number of subexcitation electrons produced by the passage of ionizing radiation through a gas has ben developed by us during the past few years. The new detector is based on the digital characterization of the electrons in the particle track produced by the ionizing radiation where the charged particle track is registered by measuring the number of electrons found in given subvolumes of the gas in the ionization chamber. The track is thus characterized by a set of integers in each volume clement, from which parameters such as the track length and energy can be measured. We have specifically developed this technique for use in the field of microdosimetry, where the study of the fluctuations in the energy deposition in the charged particle track on the order of the molecular to cellular dimensions is important in understanding the chemical and biological effects of ionizing radiation. If the charged particle is a recoil nucleus produced by a neutron interaction, the energy deposited and the linear energy transfer can be inferred from this information, allowing the detector to act as neutron spectrometer. In this paper the experimental apparatus used to make these measurements and the optical and pulsed RF electric field optimization we have performed are described. Images of particle tracks produced by {alpha} and {beta} particles, and recoil protons from the interaction of high energy neutrons with hydrogenous materials, are also presented to illustrate the sensitivity and track imaging resolution. The quality of the information gained from the detector is a very sensitive function of the gas mixture constituents, purities and pressures used in the chamber, along with the magnitude, duration, and frequency of the pulsed RF electric field.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States); National Cancer Inst., Bethesda, MD (United States); Department of Health and Human Services, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 10156829
• Report Number(s): CONF-940414-3; ON: DE94012731; CNN: Grant CA45869-03
• Resource Relation: Conference: 7. international symposium on gaseous dielectrics,Knoxville, TN (United States),24-28 Apr 1994; Other Information: PBD: [1994]
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DOSIMETRY
GAS TRACK DETECTORS
DESIGN
IONIZING RADIATIONS
IONIZATION
BREAKDOWN
MEASURING METHODS
ENERGY DEPOSITION
LET
ALPHA PARTICLES
BETA PARTICLES
PARTICLE TRACKS
SECONDARY REACTIONS
560101
440103
661300
DOSIMETRY AND MONITORING
NUCLEAR SPECTROSCOPIC INSTRUMENTATION
OTHER ASPECTS OF PHYSICAL SCIENCE