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Diamonds are very promising candidates for the neutron diagnostics in harsh environments such as fusion reactors because of their proven radiation hardness. In comparison to the standard neutron diagnostics currently used (i.e., fission chambers, silicon based detectors, scintillators) CVD diamonds are less sensitive to $\gamma $ rays, which represents a huge background in fusion devices. Furthermore, their low leakage current provides a high energy resolution. A CVD diamond based detector has been proposed for the measurement of the 14 MeV neutrons from DT fusion reaction. The prototype was arranged in a proton recoil telescope configuration, featuring a plastic converter in front of the sensitive volume, in order to induce the (n, n) reactions which generate the recoil protons. The segmentation of the sensitive volume, achieved using two crystals with two dedicated electronic readouts, allowed to perform measurements in coincidence, which suppressed the neutron-carbon elastic scattering background. A preliminary prototype was assembled and tested at FNG (Frascati Neutron Generator), showing promising results regarding efficiency and energy resolution. [ABSTRACT FROM PUBLISHER]

First neutron and X-ray beam tests on a novel 12-pixel singlecrystal diamond mosaic detector are presented and discussed. Preliminary characterization of single-pixel electronic properties, performed with α particles, results in charge carrier mobilities >2000 cm2 Vs-1 and saturation velocities of the order of 107 cm s-1. Signal stability over time, measured with a 241Am source (37 kBq activity), is longer than 5 h. Tests under an intense X-ray beam (1 Gy h-1 dose-rate) show a very good response uniformity (down to about 1% of relative standard deviation from mean value), suggesting a high level of pixel reproducibility at intermediate bias voltages (ranging from 20 to 100 V). Response uniformity reduces at voltages>200 V, due presumably to radiation-assisted detrapping effects. Preliminary results of 12-pixel simultaneous acquisitions of X-ray beam profiles and pulse height spectra under a fast neutron beam (14 MeV) are also presented. [ABSTRACT FROM AUTHOR]

This paper represents the first attempt to discuss the use of an artificial single-crystal diamond as a new microdosimeter. The Diamond MicroDosimeter (DMD) detecting region is a thin layer of highly controlled thickness (< 5~\mu m) and high purity intrinsic monocrystalline diamond grown over a backing boron doped monocrystalline diamond. This viable, small, compact and user-friendly device is able to obtain spectra of the energy deposition in sensitive volumes of the order of micrometer. The paper reports the first experimental tests performed to measure the dose distribution in terms of lineal energy and the simulation performed by the Monte Carlo code FLUKA to optimize the design of the new DMD. Advantages and shortcomings of the DMD are discussed. [ABSTRACT FROM PUBLISHER]

The use of wide-band-gap solid-state neutron detectors is expanding in environments where a compact size and high radiation hardness are needed, such as spallation neutron sources and next-generation fusion machines. Silicon carbide is a very promising material for use as a neutron detector in these fields because of its high resistance to radiation, fast response time, stability and good energy resolution. In this paper, measurements were performed with neutrons from the ISIS spallation source with two different silicon carbide detectors together with stability measurements performed in a laboratory under alpha-particle irradiation for one week. Some consideration to the impact of the casing of the detector on the detector's counting rate is given. In addition, the detector response to Deuterium-Deuterium (D-D) fusion neutrons is described by comparing neutron measurements at the Frascati Neutron Generator with a GEANT4 simulation. The good stability measurements and the assessment of the detector response function indicate that such a detector can be used as both a neutron counter and spectrometer for 2–4 MeV neutrons. Furthermore, the absence of polarization effects during neutron and alpha irradiation makes silicon carbide an interesting alternative to diamond detectors for fast neutron detection. [ABSTRACT FROM AUTHOR]