14 MeV calibration of JET neutron detectors-phase 1: Calibration and characterization of the neutron source
Journal article, 2018

In view of the planned DT operations at JET, a calibration of the JET neutron monitors at 14 MeV neutron energy is needed using a 14 MeV neutron generator deployed inside the vacuum vessel by the JET remote handling system. The target accuracy of this calibration is 10% as also required by ITER, where a precise neutron yield measurement is important, e.g. for tritium accountancy. To achieve this accuracy, the 14 MeV neutron generator selected as the calibration source has been fully characterised and calibrated prior to the in-vessel calibration of the JET monitors. This paper describes the measurements performed using different types of neutron detectors, spectrometers, calibrated long counters and activation foils which allowed us to obtain the neutron emission rate and the anisotropy of the neutron generator, i.e.The neutron flux and energy spectrum dependence on emission angle, and to derive the absolute emission rate in 4π sr. The use of high resolution diamond spectrometers made it possible to resolve the complex features of the neutron energy spectra resulting from the mixed D/T beam ions reacting with the D/T nuclei present in the neutron generator target. As the neutron generator is not a stable neutron source, several monitoring detectors were attached to it by means of an ad hoc mechanical structure to continuously monitor the neutron emission rate during the in-vessel calibration. These monitoring detectors, two diamond diodes and activation foils, have been calibrated in terms of neutrons/counts within ± 5% total uncertainty. A neutron source routine has been developed, able to produce the neutron spectra resulting from all possible reactions occurring with the D/T ions in the beam impinging on the Ti D/T target. The neutron energy spectra calculated by combining the source routine with a MCNP model of the neutron generator have been validated by the measurements. These numerical tools will be key in analysing the results from the in-vessel calibration and to derive the response of the JET neutron detectors to DT plasma neutrons starting from the response to the generator neutrons, and taking into account all the calibration circumstances.

Neutron generator

Neutron calibration

Fusion reactor

Author

X. Litaudon

Culham Science Centre

S. Abduallev

Forschungszentrum Jülich

M. Abhangi

Institute for Plasma Research India

P. Abreu

Instituto Superior Tecnico

M. Afzal

Culham Science Centre

K.M. Aggarwal

Queen's University Belfast

T. Ahlgren

University of Helsinki

J. H. Ahn

The French Alternative Energies and Atomic Energy Commission (CEA)

L. Aho-Mantila

Technical Research Centre of Finland (VTT)

N. Aiba

National Institutes for Quantum and Radiological Science and Technology

M. Airila

Technical Research Centre of Finland (VTT)

R. Albanese

University of Naples Federico II

V. Aldred

Culham Science Centre

D. Alegre

Universidad Nacional de Educación a Distancia

E. Alessi

Istituto Di Fisica Del Plasma Piero Caldirola, Milan

P B Aleynikov

ITER Organization

A. Alfier

Consorzio Rfx

A. Alkseev

National Research Centre "Kurchatov Institute"

M. Allinson

Culham Science Centre

B Alper

Culham Science Centre

E. Alves

Instituto Superior Tecnico

G. Ambrosino

University of Naples Federico II

R. Ambrosino

University Parthenope

L. Amicucci

ENEA

V. Amosov

Troitsk Institute for Innovation and Fusion Research

E. Andersson Sundén

Uppsala University

M. Angelone

ENEA

M. Anghel

National Research and Development Institute for Cryogenics and Isotopic Technologies

C. Angioni

Max Planck Society

L. Appel

Culham Science Centre

C. Appelbee

Culham Science Centre

P. Arena

University of Catania

M. Ariola

University Parthenope

D. Alegre

The French Alternative Energies and Atomic Energy Commission (CEA)

S. Arshad

Fusion for Energy Joint Undertaking

A. Ash

Culham Science Centre

N. Ashikawa

National Institutes of Natural Sciences

V. Aslanyan

Massachusetts Institute of Technology (MIT)

O. Asunta

Aalto University

F. Auriemma

Consorzio Rfx

Y. Austin

Culham Science Centre

L. Avotina

University of Latvia

M.D. Axton

Culham Science Centre

C. Ayres

Culham Science Centre

M. Bacharis

Imperial College London

A. Baciero

Laboratorio Nacional de Fusion

D. Baião

Instituto Superior Tecnico

S. Bailey

Culham Science Centre

A. Baker

Culham Science Centre

I. Balboa

Culham Science Centre

M. Balden

Max Planck Society

N. Balshaw

Culham Science Centre

R. Bament

Culham Science Centre

J.W. Banks

Culham Science Centre

Y.F. Baranov

Culham Science Centre

M.A. Barnard

Culham Science Centre

D. Barnes

Culham Science Centre

M. Barnes

University of Oxford

R. Barnsley

ITER Organization

A. Baron Wiechec

Culham Science Centre

L.B. Orte

EUROfusion Programme Management Unit

M. Baruzzo

Consorzio Rfx

V. Basiuk

The French Alternative Energies and Atomic Energy Commission (CEA)

M. Bassan

ITER Organization

R. Bastow

Culham Science Centre

A. Batista

Instituto Superior Tecnico

P. Batistoni

ENEA

R. Baughan

Culham Science Centre

B. Bauvir

ITER Organization

L. Baylor

Oak Ridge National Laboratory

B. Bazylev

Karlsruhe Institute of Technology (KIT)

J. Beal

University of York

P.S. Beaumont

Culham Science Centre

M. Beckers

Forschungszentrum Jülich

B. Beckett

Culham Science Centre

A. Becoulet

The French Alternative Energies and Atomic Energy Commission (CEA)

N. Bekris

Culham Science Centre

M. Beldishevski

Culham Science Centre

K. Bell

Culham Science Centre

F. Belli

ENEA

M. Bellinger

Culham Science Centre

Belonohy

Max Planck Society

N. Ben Ayed

Culham Science Centre

N.A. Benterman

Culham Science Centre

H. Bergsåker

Royal Institute of Technology (KTH)

J. Bernardo

Instituto Superior Tecnico

M. Bernert

Max Planck Society

M. Berry

Culham Science Centre

L. Bertalot

ITER Organization

C. Besliu

Culham Science Centre

M. N. A. Beurskens

Max Planck Society

B. Bieg

Maritime University of Szczecin

J. Bielecki

Polish Academy of Sciences

T. Biewer

Oak Ridge National Laboratory

M. Bigi

Consorzio Rfx

P. Bílková

Czech Academy of Sciences

F. Binda

Uppsala University

A. Bisoffi

University of Trento

J. P. S. Bizarro

Instituto Superior Tecnico

C. Björkas

University of Helsinki

Dimitriy Yadykin

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Jan Weiland

Chalmers, Physics

Nuclear Fusion

0029-5515 (ISSN)

Vol. 58 2 026012

Subject Categories

Accelerator Physics and Instrumentation

Subatomic Physics

Fusion, Plasma and Space Physics

DOI

10.1088/1741-4326/aa98f6

More information

Latest update

4/2/2022 1