Deuterium density profile determination at JET using a neutron camera and a neutron spectrometer

Eriksson, J.; Castegnetti, G.; Conroy, S.; Ericsson, Göran; Giacomelli, L.; Hellesen, C.; Contributors, Jet‐Efda

doi:10.1063/1.4889907

Cited by 4 publications

(3 citation statements)

References 14 publications

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“…In a fusion plasma, the energy distribution of the neutrons is dependent on the velocity distribution of the reactants. [1][2][3][4] Neutron measurements can therefore be used to investigate the ion velocity distribution of the plasma ions, [5][6][7] which in turn helps in estimating other plasma parameters such as the ion temperature, 8,9 the ion densities, [10][11][12][13] the plasma rotation, 14 and the fraction of neutrons emitted in reactions between thermal ions to those emitted in reactions involving non-thermal fuel ions. 15,16 However, relating neutron measurements to these physics quantities requires modeling of the neutron spectra in the plasma,…”

Section: Introductionmentioning

confidence: 99%

Estimating the neutron yield in a deuterium plasma with the JET neutron camera

Hägg

Binda²,

Conroy

et al. 2023

Review of Scientific Instruments

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The JET neutron camera is a well-established detector system at JET, which has 19 sightlines each equipped with a liquid scintillator. The system measures a 2D profile of the neutron emission from the plasma. A first principle physics method is used to estimate the DD neutron yield that is based on JET neutron camera measurements and is independent of other neutron measurements. This paper details the data reduction techniques, models of the neutron camera, simulations of neutron transport, and detector responses used to this end. The estimate uses a simple parameterized model of the neutron emission profile. The method makes use of the JET neutron camera’s upgraded data acquisition system. It also accounts for neutron scattering near the detectors and transmission through the collimator. These components together contribute to 9% of the detected neutron rate above a 0.5 MeVee energy threshold. Despite the simplicity of the neutron emission profile model, the DD neutron yield estimate falls on average within 10% agreement with a corresponding estimate from the JET fission chambers. The method can be improved by considering more advanced neutron emission profiles. It can also be expanded to estimate the DT neutron yield with the same methodology.

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Section: Introductionmentioning

confidence: 99%

Estimating the neutron yield in a deuterium plasma with the JET neutron camera

Hägg

Binda²,

Conroy

et al. 2023

Review of Scientific Instruments

View full text Add to dashboard Cite

show abstract

“…For the International Thermonuclear Experimental Reactor (ITER) tokamak, Y n diagnosis and analysis is expected to provide crucial insight on plasmas, as well as information for protection and control [3]. Neutron diagnostics using the Joint European Torus (JET) neutron camera and the neutron time--of-fl ight spectrometer are used to estimate the fuel density profi le in the JET deuterium plasma [4]. This is key to the operation and control of a burning fusion plasma.…”

Section: Introductionmentioning

confidence: 99%

“…The reference is still neutron activation [1,5], which consists mainly of irradiating an indium sample at well-known geometries, with a known photon detection effi ciency, and measuring the neutron-induced activity. Knowledge of the neutron reaction cross section is essential for estimating the neutron fl ux [4,10].…”

Section: Introductionmentioning

confidence: 99%

A new concept of fusion neutron monitoring for PF-1000 device

et al. 2017

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The power output of plasma experiments and fusion reactors is a crucial parameter. It is determined by neutron yields that are proportional and directly related to the fusion yield. The number of emitted neutrons should be known for safety reasons and for neutron budget management. The PF-1000 is the large plasma facility based on the plasma focus phenomenon. PF-1000 is operating in the Institute of Plasma Physics and Laser Microfusion in Warsaw. Neutron yield changes during subsequent pulses, which is immanent part of this type device and so it must be monitored in terms of neutron emission. The reference diagnostic intended for this purpose is the silver activation counter (SAC) used for many years. Our previous studies demonstrated the applicability of radio-yttrium for neutron yield measurements during the deuterium campaign on the PF-1000 facility. The obtained results were compared with data from silver activation counter and shown linear dependence but with some protuberances in local scale. Correlation between results for both neutron monitors was maintained. But the yttrium monitor registered the fast energy neutron that reached measurement apparatus directly from the plasma pinch. Based on the preliminary experiences, the yttrium monitor was designed to automatically register neutron-induced yttrium activity. The MCNP geometrical model of PF-1000 and yttrium monitor were both used for calculation of the activation coefficient for yttrium. The yttrium monitor has been established as the permanent diagnostic for monitoring fusion reactions in the PF-1000 device.

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Recoil-proton track imaging as a new way for neutron spectrometry measurements

Liu

Zhang

et al. 2018

Sci Rep

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Recoil-proton track imaging (RPTI) is an attractive technique to optically record the tracks of recoil protons in scintillation gas by using realtime imaging devices. For the first time, its use as an online nuclear track detector for neutron spectrometry measurements (NSM) is explored. Based on the RPTI methodology for NSM, a very basic detector system is designed, consisting of the neutron-to-proton recoil system and proton track imaging system. Satisfactory performance of the RPTI neutron spectrometer has been examined with a series of Monte Carlo simulations. Moreover, using well-defined line-proton sources from a tandem accelerator, the capability of the detector for imaging proton tracks at the single-particle level in real time has been validated in preliminary experiments. From the clear single proton tracks in the images, the proton ranges were easily distinguished, and precise proton energy spectra were unfolded, laying a solid experimental foundation for the future implementation of NSM.

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Deuterium density profile determination at JET using a neutron camera and a neutron spectrometer

Cited by 4 publications

References 14 publications

Estimating the neutron yield in a deuterium plasma with the JET neutron camera

Estimating the neutron yield in a deuterium plasma with the JET neutron camera

A new concept of fusion neutron monitoring for PF-1000 device

Recoil-proton track imaging as a new way for neutron spectrometry measurements

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