Proton recoil detector of fusion neutrons using natural diamond

Journal Article · Wed Jan 01 04:00:00 EST 1997 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1147668· OSTI ID:451820

Maqueda, R J; Barnes, C W; Han, S S; Staples, P A; Wagner, R S ^[1]

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1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

Diamond, with its high radiation damage resistance, is an attractive alternative to silicon for neutron measurements in next step fusion experiments. A 200-{mu}m-thick type IIa natural diamond with Ti/Au contacts was tested at the LAMPF-WNR facility by time-of-flight neutron energy identification. The crystal, having a carrier lifetime of up to 1 ns, was arranged in a low-energy-resolution, high-sensitivity proton recoil telescope consisting of a polyethylene radiator and a low-energy-proton Teflon filter. This arrangement is similar to the triton burnup monitor of Croft {ital et al.} [Rev. Sci. Instrum. {bold 64}, 1418 (1993)], where a silicon photodiode was used as a recoil proton detector. The observed sensitivity for 14 MeV neutrons (DT) is (1.25{plus_minus}0.15){times}10{sup {minus}3} counts/neutron. However, a high contribution of neutron-induced events in the diamond, mainly carbon (A=12) recoils, was observed. A one-dimensional calculation for the detector response to carbon recoil and proton deposition is compared to the measurements. Poor energy resolution of the diamond detector precludes pulse height discrimination between direct 2.5 MeV neutrons events and proton events corresponding to 14 MeV neutrons. Therefore, an overall DT/DD neutron sensitivity ratio of only {approximately}6.5 is achieved. This value is much lower than the ratio of 540 reported by Croft {ital et al.} in their silicon (A=28) monitor.

• Research Organization: Los Alamos National Laboratory
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 451820
• Report Number(s): CONF-960543--
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 1 Vol. 68; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
COMPUTERIZED SIMULATION
DEUTERON REACTIONS
DIAMONDS
ENERGY RESOLUTION
MEV RANGE
NEUTRON DETECTION
NEUTRON EMISSION
NEUTRON SPECTROMETERS
PLASMA DIAGNOSTICS
PROTON RECOIL DETECTORS
SEMICONDUCTOR DETECTORS
SENSITIVITY
THERMONUCLEAR REACTORS
TRITON REACTIONS
diamond
fusion reactor ignition
time of flight spectrometers