1
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Torregrosa-Martin C, Ibarra A, Aguilar J, Ambi F, Arranz F, Arbeiter F, Bagnasco A, Becerril S, Bernardi D, Bolzon B, Botta E, Brenneis B, Cappelli M, Cara P, Castellanos J, Cosic D, De la Morena C, Diez A, Ericsson G, García A, García M, Garcinuño B, Gutiérrez J, Gutiérrez V, Jimenez-Rey D, Dezsi T, Ferreira MJ, Fiore S, Krolas W, Lorenzo R, Luque M, Maciá L, Marroncle J, Martin-Fuertes F, Marugán J, Maestre J, Meléndez C, Miccichè G, Mollá J, Moreno A, Nitti F, Núñez C, Ogando F, Pinna T, Oliver C, Podadera I, Prieto C, Prokopowicz R, Qiu Y, Rapisarda D, Regidor D, Rodríguez E, Sabogal A, Sánchez-Herranz D, Sanmarti M, Seguí L, Serikov A, Tadić T, Talarowska A, Wiacek U, Weber M, Valenzuela J, Zsakai A. Overview of IFMIF-DONES diagnostics: Requirements and techniques. Fusion Engineering and Design 2023. [DOI: 10.1016/j.fusengdes.2023.113556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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2
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Marcinkevicius B, Eriksson J, Hjalmarsson A, Conroy S, Ericsson G. Fuel ion ratio determination using the 14 MeV Tandem neutron spectrometer for JET DTE1 campaign discharges. Fusion Engineering and Design 2022. [DOI: 10.1016/j.fusengdes.2022.113259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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3
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Nocente M, Kiptily V, Tardocchi M, Bonofiglo PJ, Craciunescu T, Molin AD, De La Luna E, Eriksson J, Garcia J, Ghani Z, Gorini G, Hägg L, Kazakov Y, Lerche E, Maggi CF, Mantica P, Marcer G, Maslov M, Putignano O, Rigamonti D, Salewski M, Sharapov S, Siren P, Stancar Z, Zohar A, Beaumont P, Crombe K, Ericsson G, Garcia-Munoz M, Keeling D, King D, Kirov K, Nave MFF, Ongena J, Patel A, Perez von Thun C. Fusion product measurements by nuclear diagnostics in the Joint European Torus deuterium-tritium 2 campaign (invited). Rev Sci Instrum 2022; 93:093520. [PMID: 36182523 DOI: 10.1063/5.0101767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/20/2022] [Indexed: 06/16/2023]
Abstract
A new deuterium-tritium experimental, DTE2, campaign has been conducted at the Joint European Torus (JET) between August 2021 and late December 2021. Motivated by significant enhancements in the past decade at JET, such as the ITER-like wall and enhanced auxiliary heating power, the campaign achieved a new fusion energy world record and performed a broad range of fundamental experiments to inform ITER physics scenarios and operations. New capabilities in the area of fusion product measurements by nuclear diagnostics were available as a result of a decade long enhancement program. These have been tested for the first time in DTE2 and a concise overview is provided here. Confined alpha particle measurements by gamma-ray spectroscopy were successfully demonstrated, albeit with limitations at neutron rates higher than some 1017 n/s. High resolution neutron spectroscopy measurements with the magnetic proton recoil instrument were complemented by novel data from a set of synthetic diamond detectors, which enabled studies of the supra-thermal contributions to the neutron emission. In the area of escaping fast ion diagnostics, a lost fast ion detector and a set of Faraday cups made it possible to determine information on the velocity space and poloidal distribution of the lost alpha particles for the first time. This extensive set of data provides unique information for fundamental physics studies and validation of the numerical models, which are key to inform the physics and scenarios of ITER.
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Affiliation(s)
- M Nocente
- Department of Physics, University of Milano-Bicocca, Milan 20126, Italy
| | - V Kiptily
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - M Tardocchi
- Institute for Plasma Science and Technology, National Research Council, Milan 20125, Italy
| | - P J Bonofiglo
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - T Craciunescu
- Institute of Atomic Physics, Magurele-Bucharest 077125, Romania
| | - A Dal Molin
- Institute for Plasma Science and Technology, National Research Council, Milan 20125, Italy
| | - E De La Luna
- Laboratorio Nacional de Fusión, CIEMAT, Madrid 28040, Spain
| | - J Eriksson
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-75120, Sweden
| | - J Garcia
- CEA, IRFM, Saint Paul lez Durance 13115, France
| | - Z Ghani
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - G Gorini
- Department of Physics, University of Milano-Bicocca, Milan 20126, Italy
| | - L Hägg
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-75120, Sweden
| | - Y Kazakov
- Laboratory for Plasma Physics, LPP ERM/KMS, Brussels 1000, Belgium
| | - E Lerche
- Laboratory for Plasma Physics, LPP ERM/KMS, Brussels 1000, Belgium
| | - C F Maggi
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - P Mantica
- Institute for Plasma Science and Technology, National Research Council, Milan 20125, Italy
| | - G Marcer
- Department of Physics, University of Milano-Bicocca, Milan 20126, Italy
| | - M Maslov
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - O Putignano
- Department of Physics, University of Milano-Bicocca, Milan 20126, Italy
| | - D Rigamonti
- Institute for Plasma Science and Technology, National Research Council, Milan 20125, Italy
| | - M Salewski
- Department of Physics, Technical University of Denmark, Kgs. Lyngby 2800, Denmark
| | - S Sharapov
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - P Siren
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - Z Stancar
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - A Zohar
- Jožef Stefan Institute, Ljubljana 1000, Slovenia
| | - P Beaumont
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - K Crombe
- Laboratory for Plasma Physics, LPP ERM/KMS, Brussels 1000, Belgium
| | - G Ericsson
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-75120, Sweden
| | - M Garcia-Munoz
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville 41012, Spain
| | - D Keeling
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - D King
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - K Kirov
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - M F F Nave
- Instituto de Plasmas e Fusao Nuclear, IST, Universidade de Lisboa, Lisboa 1049-001, Portugal
| | - J Ongena
- Laboratory for Plasma Physics, LPP ERM/KMS, Brussels 1000, Belgium
| | - A Patel
- United Kingdom Atomic Energy Authority, Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
| | - C Perez von Thun
- Institute of Plasma Physics and Laser Microfusion, Warsaw 01-497, Poland
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4
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Sahlberg A, Eriksson J, Conroy S, Ericsson G, Hägg L, Giacomelli L, Belli F. Forward modeling of pile-up events in liquid scintillator detectors for neutron emission spectroscopy. Rev Sci Instrum 2021; 92:083502. [PMID: 34470438 DOI: 10.1063/5.0052260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
When using liquid scintillator detectors to measure the neutron emission spectrum from fusion plasmas, the problem of pile-up distortion can be significant. Because of the large neutron rates encountered in many fusion experiments, some pile-up distortion can remain even after applying traditional pile-up elimination methods, which alters the shape of the measured light-yield spectrum and influences the spectroscopic analysis. Particularly, pile-up events appear as a high-energy tail in the measured light-yield spectrum, which obfuscates the contribution that supra-thermal ions make to the energy spectrum. It is important to understand the behavior of such "fast ions" in fusion plasmas, and it is hence desirable to be able to measure their contribution to the neutron spectrum as accurately as possible. This paper presents a technique for incorporating distortion from undetected pile-up events into the analysis of the light-yield spectrum, hence compensating for pile-up distortion. The spectral contribution from undetected pile-up events is determined using Monte Carlo methods and is included in the spectroscopic study as a pile-up component. The method is applied to data from an NE213 scintillator detector at JET and validated by comparing with results from the time-of-flight spectrometer TOFOR, which is not susceptible to pile-up distortion. Based on the results, we conclude that the suggested analysis method helps counteract the problem of pile-up effects and improves the possibilities for extracting accurate fast-ion information from the light-yield spectrum.
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Affiliation(s)
- A Sahlberg
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - J Eriksson
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - S Conroy
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - G Ericsson
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - L Hägg
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - L Giacomelli
- Istituto per la Scienza e la Tecnologia dei Plasmi, Consiglio Nazionale delle Ricerche, 20125 Milano, Italy
| | - F Belli
- ENEA C. R. Frascati, Dipartimento FSN, via E. Fermi 45, 00044 Frascati (Roma), Italy
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5
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Eriksson B, Conroy S, Ericsson G, Eriksson J, Giacomelli L, Hjalmarsson A, Weiszflog M. New method for time alignment and time calibration of the TOFOR time-of-flight neutron spectrometer at JET. Rev Sci Instrum 2021; 92:033538. [PMID: 33820020 DOI: 10.1063/5.0041126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 03/04/2021] [Indexed: 06/12/2023]
Abstract
The TOFOR time-of-flight (TOF) neutron spectrometer at the Joint European Torus (JET) is composed of 5 start (S1) and 32 stop (S2) scintillation detectors. Recently, the data acquisition system (DAQ) of TOFOR was upgraded to equip each of the 37 detectors with its own waveform digitizer to allow for correlated time and pulse height analysis of the acquired data. Due to varying cable lengths and different pulse processing pathways in the new DAQ system, the 160 (5 · 32) different TOF pairs of start-stop detectors must be time-aligned to enable the proper construction of a summed TOF spectrum. Given the time (energy) resolution required by the entire spectrometer system to measure different plasma neutron emission components, it is of importance to align the detector pairs to each other with sub-nanosecond precision. Previously, the alignment partially depended on using fusion neutron data from Ohmic heating phases of JET experimental pulses. The dependence on fusion neutron data in the time alignment process is, however, unsatisfactory as it involves data one would wish to include in an independent analysis for physics results. In this work, we describe a method of time-aligning the detector pairs by using gamma rays. Given the known geometry and response of TOFOR to gamma rays, the time alignment of the detector pairs is found by examining gamma events interacting in coincidence in both S1-S1 and S1-S2 detector combinations. Furthermore, a technique for separating neutron and gamma events in the different detector sets is presented. Finally, the time-aligned system is used to analyze neutron data from Ohmic phases for different plasma conditions and to estimate the Ohmic fuel ion temperature.
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Affiliation(s)
- B Eriksson
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20, Sweden
| | - S Conroy
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20, Sweden
| | - G Ericsson
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20, Sweden
| | - J Eriksson
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20, Sweden
| | - L Giacomelli
- Instituto de Fisica del Plasma "P. Caldirola," I-20126 Milano, Italy
| | - A Hjalmarsson
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20, Sweden
| | - M Weiszflog
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20, Sweden
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6
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Marcinkevicius B, Hjalmarsson A, Andersson Sundén E, Ericsson G. Thin foil proton recoil spectrometer performance study for application in DT plasma measurements. Rev Sci Instrum 2018; 89:10I107. [PMID: 30399976 DOI: 10.1063/1.5038924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 06/08/2018] [Indexed: 06/08/2023]
Abstract
The Thin foil Proton Recoil (TPR) technique has previously been used for deuterium-tritium fusion neutron diagnostics [N. P. Hawkes et al., Rev. Sci. Instrum. 70, 1134 (1999)] and is one of the candidates put forward for use in ITER as part of the high resolution neutron spectrometer (HRNS) system [E. A. Sundén et al., Nucl. Instrum. Methods Phys. Res., Sect. A 701, 62 (2013)]. For ITER, the neutron spectrometer's main purposes are to determine the fuel ion density ratio as well as the ion temperature in DT plasma. This work focuses on testing the capability of a proton telescope detector intended for use as part of the TPR spectrometer. The proton telescope has been tested using proton energies in the range of 3-8 MeV. The experimental results cover energy calibration, resolution estimation, and testing the spectrometer's capability to perform background separation using ΔE - E energy cuts. In addition, spectrometer performance in terms of signal to background ratios for ITER-like DT plasma conditions is estimated using Monte-Carlo simulations. Results show that the TPR spectrometer geometry dominates in determining the energy resolution and the ΔE - E energy cuts will significantly reduce the background. In addition, the estimated spectrometer count rates in ITER-like conditions fall below 20 kHz per detector segment.
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Affiliation(s)
- B Marcinkevicius
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - A Hjalmarsson
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - E Andersson Sundén
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - G Ericsson
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
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7
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Sjöstrand H, Sundén EA, Bertalot L, Conroy S, Ericsson G, Johnson MG, Giacomelli L, Gorini G, Hellesen C, Hjalmarsson A, Källne J, Popovichev S, Ronchi E, Weiszflog M, Tardocchi M. Fusion Power Measurement Using a Combined Neutron Spectrometer-Camera System at JET. Fusion Science and Technology 2017. [DOI: 10.13182/fst10-a9370] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Henrik Sjöstrand
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - E. Andersson Sundén
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - L. Bertalot
- ITER Diagnostic Division, ITER, Cadarache Centre, 13108 St. Paul lez Durance, France
| | - S. Conroy
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - G. Ericsson
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - M. Gatu Johnson
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - L. Giacomelli
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - G. Gorini
- Physics Department, Milano-Bicocca University, and Istituto di Fisica del Plasma del CNR, Milan, Italy (EURATOM-ENEA-CNR Association)
| | - C. Hellesen
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - A. Hjalmarsson
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - J. Källne
- JET-EFDA, Culham Science Centre, OX14 3DB, Abingdon, United Kingdom
| | - S. Popovichev
- EURATOM0UKAEA Fusion Association, Culham Science Centre, Abingdon, United Kingdom
| | - E. Ronchi
- JET-EFDA, Culham Science Centre, OX14 3DB, Abingdon, United Kingdom
| | - M. Weiszflog
- Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala, Sweden (EURATOM-VR Association)
| | - M. Tardocchi
- Physics Department, Milano-Bicocca University, and Istituto di Fisica del Plasma del CNR, Milan, Italy (EURATOM-ENEA-CNR Association)
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8
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Dressel S, Sandström C, Ericsson G. A meta-analysis of studies on attitudes toward bears and wolves across Europe 1976-2012. Conserv Biol 2015; 29:565-574. [PMID: 25412113 DOI: 10.1111/cobi.12420] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 07/29/2014] [Indexed: 06/04/2023]
Abstract
The ranges of wolves (Canis lupus) and bears (Ursus arctos) across Europe have expanded recently, and it is important to assess public attitudes toward this expansion because responses toward these species vary widely. General attitudes toward an object are good predictors of broad behavioral patterns; thus, attitudes toward wolves and bears can be used as indicators to assess the social foundation for future conservation efforts. However, most attitude surveys toward bears and wolves are limited in scope, both temporally and spatially, and provide only a snapshot of attitudes. To extend the results of individual surveys over a much larger temporal and geographical range so as to identify transnational patterns and changes in attitudes toward bears and wolves over time, we conducted a meta-analysis. Our analysis included 105 quantitative surveys conducted in 24 countries from 1976 to 2012. Across Europe, people's attitudes were more positive toward bears than wolves. Attitudes toward bears became more positive over time, but attitudes toward wolves seemed to become less favorable the longer people coexisted with them. Younger and more educated people had more positive attitudes toward wolves and bears than people who had experienced damage from these species, and farmers and hunters had less positive attitudes toward wolves than the general public. For bears attitudes among social groups did not differ. To inform conservation of large carnivores, we recommend that standardized longitudinal surveys be established to monitor changes in attitudes over time relative to carnivore population development. Our results emphasize the need for interdisciplinary research in this field and more advanced explanatory models capable of capturing individual and societal responses to changes in large carnivore policy and management.
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Affiliation(s)
- S Dressel
- Department of Wildlife, Fish & Environmental Studies, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
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9
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Hellesen C, Skiba M, Dzysiuk N, Weiszflog M, Hjalmarsson A, Ericsson G, Conroy S, Andersson-Sundén E, Eriksson J, Binda F. Prospects for measuring the fuel ion ratio in burning ITER plasmas using a DT neutron emission spectrometer. Rev Sci Instrum 2014; 85:11D825. [PMID: 25430238 DOI: 10.1063/1.4890577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The fuel ion ratio nt/nd is an essential parameter for plasma control in fusion reactor relevant applications, since maximum fusion power is attained when equal amounts of tritium (T) and deuterium (D) are present in the plasma, i.e., nt/nd = 1.0. For neutral beam heated plasmas, this parameter can be measured using a single neutron spectrometer, as has been shown for tritium concentrations up to 90%, using data obtained with the MPR (Magnetic Proton Recoil) spectrometer during a DT experimental campaign at the Joint European Torus in 1997. In this paper, we evaluate the demands that a DT spectrometer has to fulfill to be able to determine nt/nd with a relative error below 20%, as is required for such measurements at ITER. The assessment shows that a back-scattering time-of-flight design is a promising concept for spectroscopy of 14 MeV DT emission neutrons.
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Affiliation(s)
- C Hellesen
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - M Skiba
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - N Dzysiuk
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - M Weiszflog
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - A Hjalmarsson
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - G Ericsson
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - S Conroy
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - E Andersson-Sundén
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - J Eriksson
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
| | - F Binda
- Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala, Sweden
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10
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Binda F, Ericsson G, Eriksson J, Hellesen C, Conroy S, Sundén EA. Forward fitting of experimental data from a NE213 neutron detector installed with the magnetic proton recoil upgraded spectrometer at JET. Rev Sci Instrum 2014; 85:11E123. [PMID: 25430302 DOI: 10.1063/1.4895565] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper, we present the results obtained from the data analysis of neutron spectra measured with a NE213 liquid scintillator at JET. We calculated the neutron response matrix of the instrument combining MCNPX simulations, a generic proton light output function measured with another detector and the fit of data from ohmic pulses. For the analysis, we selected a set of pulses with neutral beam injection heating (NBI) only and we applied a forward fitting procedure of modeled spectral components to extract the fraction of thermal neutron emission. The results showed the same trend of the ones obtained with the dedicated spectrometer TOFOR, even though the values from the NE213 analysis were systematically higher. This discrepancy is probably due to the different lines of sight of the two spectrometers (tangential for the NE213, vertical for TOFOR). The uncertainties on the thermal fraction estimates were from 4 to 7 times higher than the ones from the TOFOR analysis.
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Affiliation(s)
- F Binda
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - G Ericsson
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - J Eriksson
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - C Hellesen
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - S Conroy
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - E Andersson Sundén
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
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11
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Jacobsen AS, Salewski M, Eriksson J, Ericsson G, Hjalmarsson A, Korsholm SB, Leipold F, Nielsen SK, Rasmussen J, Stejner M. Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET. Rev Sci Instrum 2014; 85:11E103. [PMID: 25430282 DOI: 10.1063/1.4885477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR.
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Affiliation(s)
- A S Jacobsen
- Association Euratom - DTU, Technical University of Denmark, Department of Physics, Kgs. Lyngby, Denmark
| | - M Salewski
- Association Euratom - DTU, Technical University of Denmark, Department of Physics, Kgs. Lyngby, Denmark
| | - J Eriksson
- Association Euratom - VR, Uppsala University, Department of Physics and Astronomy, Uppsala, Sweden
| | - G Ericsson
- Association Euratom - VR, Uppsala University, Department of Physics and Astronomy, Uppsala, Sweden
| | - A Hjalmarsson
- Association Euratom - VR, Uppsala University, Department of Physics and Astronomy, Uppsala, Sweden
| | - S B Korsholm
- Association Euratom - DTU, Technical University of Denmark, Department of Physics, Kgs. Lyngby, Denmark
| | - F Leipold
- Association Euratom - DTU, Technical University of Denmark, Department of Physics, Kgs. Lyngby, Denmark
| | - S K Nielsen
- Association Euratom - DTU, Technical University of Denmark, Department of Physics, Kgs. Lyngby, Denmark
| | - J Rasmussen
- Association Euratom - DTU, Technical University of Denmark, Department of Physics, Kgs. Lyngby, Denmark
| | - M Stejner
- Association Euratom - DTU, Technical University of Denmark, Department of Physics, Kgs. Lyngby, Denmark
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12
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Klimek I, Cecconello M, Sharapov SE, Harrison J, Ericsson G. Determination of hydrogen/deuterium ratio with neutron measurements on MAST. Rev Sci Instrum 2014; 85:11E109. [PMID: 25430288 DOI: 10.1063/1.4889910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
On MAST, compressional Alfvén eigenmodes can be destabilized by the presence of a sufficiently large population of energetic particles in the plasma. This dependence was studied in a series of very similar discharges in which increasing amounts of hydrogen were puffed into a deuterium plasma. A simple method to estimate the isotopic ratio nH/nD using neutron emission measurements is here described. The inferred isotopic ratio ranged from 0.0 to 0.6 and no experimental indication of changes in radial profile of nH/nD were observed. These findings are confirmed by TRANSP/NUBEAM simulations of the neutron emission.
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Affiliation(s)
- I Klimek
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - M Cecconello
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - S E Sharapov
- CCFE, Culham Science Centre, Abingdon, United Kingdom
| | - J Harrison
- CCFE, Culham Science Centre, Abingdon, United Kingdom
| | - G Ericsson
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
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13
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Eriksson J, Castegnetti G, Conroy S, Ericsson G, Giacomelli L, Hellesen C. Deuterium density profile determination at JET using a neutron camera and a neutron spectrometer. Rev Sci Instrum 2014; 85:11E106. [PMID: 25430285 DOI: 10.1063/1.4889907] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this work we estimate the fuel ion density profile in deuterium plasmas at JET, using the JET neutron camera, the neutron time-of-flight spectrometer TOFOR, and fusion reactivities modeled by the transport code TRANSP. The framework has been tested using synthetic data, which showed that the density profile could be reconstructed with an average accuracy of the order of 10 %. The method has also been applied to neutron measurements from a neutral beam heated JET discharge, which gave nd/ne ≈ 0.6 ± 0.3 in the plasma core and nd/ne ≈ 0.4 ± 0.3 towards the edge. Correction factors for detector efficiencies, neutron attenuation, and back-scattering are not yet included in the analysis; future work will aim at refining the estimated density.
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Affiliation(s)
- J Eriksson
- EURATOM-VR, Department of Physics and Astronomy, Uppsala University, Sweden
| | - G Castegnetti
- EURATOM-VR, Department of Physics and Astronomy, Uppsala University, Sweden
| | - S Conroy
- EURATOM-VR, Department of Physics and Astronomy, Uppsala University, Sweden
| | - G Ericsson
- EURATOM-VR, Department of Physics and Astronomy, Uppsala University, Sweden
| | - L Giacomelli
- Department of Physics, Università degli Studi di Milano-Bicocca, Milano, Italy
| | - C Hellesen
- EURATOM-VR, Department of Physics and Astronomy, Uppsala University, Sweden
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14
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Weiszflog M, Sangaroon S, Cecconello M, Conroy S, Ericsson G, Klimek I, Keeling D, Martin R, Turnyanskiy M. Conceptual design of a neutron camera for MAST Upgrade. Rev Sci Instrum 2014; 85:11E121. [PMID: 25430300 DOI: 10.1063/1.4891926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This paper presents two different conceptual designs of neutron cameras for Mega Ampere Spherical Tokamak (MAST) Upgrade. The first one consists of two horizontal cameras, one equatorial and one vertically down-shifted by 65 cm. The second design, viewing the plasma in a poloidal section, also consists of two cameras, one radial and the other one with a diagonal view. Design parameters for the different cameras were selected on the basis of neutron transport calculations and on a set of target measurement requirements taking into account the predicted neutron emissivities in the different MAST Upgrade operating scenarios. Based on a comparison of the cameras' profile resolving power, the horizontal cameras are suggested as the best option.
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Affiliation(s)
- M Weiszflog
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala, Sweden
| | - S Sangaroon
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala, Sweden
| | - M Cecconello
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala, Sweden
| | - S Conroy
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala, Sweden
| | - G Ericsson
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala, Sweden
| | - I Klimek
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala, Sweden
| | - D Keeling
- CCFE, Culham Science Centre, Abingdon, United Kingdom
| | - R Martin
- CCFE, Culham Science Centre, Abingdon, United Kingdom
| | - M Turnyanskiy
- ITER Physics Department, EFDA CSU Garching, Boltzmannstrae 2, D-85748 Garching, Germany
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15
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Cazzaniga C, Sundén EA, Binda F, Croci G, Ericsson G, Giacomelli L, Gorini G, Griesmayer E, Grosso G, Kaveney G, Nocente M, Perelli Cippo E, Rebai M, Syme B, Tardocchi M. Single crystal diamond detector measurements of deuterium-deuterium and deuterium-tritium neutrons in Joint European Torus fusion plasmas. Rev Sci Instrum 2014; 85:043506. [PMID: 24784606 DOI: 10.1063/1.4870584] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
First simultaneous measurements of deuterium-deuterium (DD) and deuterium-tritium neutrons from deuterium plasmas using a Single crystal Diamond Detector are presented in this paper. The measurements were performed at JET with a dedicated electronic chain that combined high count rate capabilities and high energy resolution. The deposited energy spectrum from DD neutrons was successfully reproduced by means of Monte Carlo calculations of the detector response function and simulations of neutron emission from the plasma, including background contributions. The reported results are of relevance for the development of compact neutron detectors with spectroscopy capabilities for installation in camera systems of present and future high power fusion experiments.
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Affiliation(s)
- C Cazzaniga
- Department of Physics "G. Occhialini," University of Milano Bicocca, Piazza della Scienza 3, Milano, Italy
| | - E Andersson Sundén
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - F Binda
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - G Croci
- Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano, Italy
| | - G Ericsson
- Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala, Sweden
| | - L Giacomelli
- Department of Physics "G. Occhialini," University of Milano Bicocca, Piazza della Scienza 3, Milano, Italy
| | - G Gorini
- Department of Physics "G. Occhialini," University of Milano Bicocca, Piazza della Scienza 3, Milano, Italy
| | - E Griesmayer
- Atominstitut, Vienna University of Technology, Austria
| | - G Grosso
- Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano, Italy
| | - G Kaveney
- Culham Centre for Fusion Energy, Culham OX143DB, United Kingdom
| | - M Nocente
- Department of Physics "G. Occhialini," University of Milano Bicocca, Piazza della Scienza 3, Milano, Italy
| | - E Perelli Cippo
- Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano, Italy
| | - M Rebai
- Department of Physics "G. Occhialini," University of Milano Bicocca, Piazza della Scienza 3, Milano, Italy
| | - B Syme
- Culham Centre for Fusion Energy, Culham OX143DB, United Kingdom
| | - M Tardocchi
- Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano, Italy
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16
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Skiba M, Weiszflog M, Hjalmarsson A, Ericsson G, Hellesen C, Conroy S, Andersson-Sundén E, Eriksson J, Binda F. Fully digital data acquisition system for the neutron time-of-flight spectrometer TOFOR at JET. Rev Sci Instrum 2012; 83:10D907. [PMID: 23130798 DOI: 10.1063/1.4734493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A prototype of a fully digital data acquisition system based on 1 Gsps 12 bit digitizers for the TOFOR fusion neutron spectrometer at JET is assessed. The prototype system enables the use of geometry-based background discrimination techniques, which are modeled, evaluated, and compared to experimental data. The experimental results are in line with the models and show a significant improvement in signal-to-background ratio in measured time-of-flight spectrum compared to the existing data acquisition system.
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Affiliation(s)
- M Skiba
- Department of physics and astronomy, Uppsala University, Sweden.
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17
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Hellesen C, Eriksson J, Conroy S, Ericsson G, Skiba M, Weiszflog M. Fuel ion ratio measurements in reactor relevant neutral beam heated fusion plasmas. Rev Sci Instrum 2012; 83:10D916. [PMID: 23130799 DOI: 10.1063/1.4738647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this paper, we present a method to derive n(t)/n(d) using the ratio of the thermonuclear neutron emission to the beam-target neutron emission. We apply it to neutron spectroscopy data from the magnetic proton recoil spectrometer taken during the deuterium tritium experiment at JET. n(t)/n(d)-values obtained using neutron spectroscopy are in qualitative agreement with those from other diagnostics measuring the isotopic composition of the exhaust in the divertor.
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Affiliation(s)
- C Hellesen
- Department of Physics and Astronomy, Applied Nuclear Physics, Uppsala University, Sweden.
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18
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Sangaroon S, Cecconello M, Conroy S, Weiszflog M, Turnyanskiy M, Wodniak I, Ericsson G. Validation of neutron emission profiles in MAST with a collimated neutron monitor. Rev Sci Instrum 2012; 83:10D910. [PMID: 23126913 DOI: 10.1063/1.4732059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A neutron camera with liquid scintillator detectors is used in MAST to measure the neutron emissivity from D(d,n)(3)He reactions along collimated lines of sight. In this work, the measured recoil proton pulse height spectra generated in the detectors by the incident neutrons is modelled taking into account the energy spectrum of the generated neutrons, their spatial distribution and transport to the detectors as well as the detector's response function. The contribution of scattered neutrons to the pulse height spectrum is also modelled. Good agreement is found between the experimental data and the simulations. Examples are given showing the sensitivity of the recoil proton pulse height spectra to different observation angles with respect the neutral beam injection and the plasma rotation direction.
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Affiliation(s)
- S Sangaroon
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Sweden.
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19
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Månsson J, Bunnefeld N, Andrén H, Ericsson G. Spatial and temporal predictions of moose winter distribution. Oecologia 2012; 170:411-9. [PMID: 22437909 DOI: 10.1007/s00442-012-2305-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 03/06/2012] [Indexed: 11/25/2022]
Affiliation(s)
- J Månsson
- Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Sciences, Riddarhyttan, Sweden.
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20
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Moro F, Esposito B, Marocco D, Villari R, Petrizzi L, Sunden EA, Conroy S, Ericsson G, Johnson MG, Dapena M. Neutronic calculations in support of the design of the ITER High Resolution Neutron Spectrometer. Fusion Engineering and Design 2011. [DOI: 10.1016/j.fusengdes.2011.02.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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21
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Cecconello M, Turnyanskiy M, Conroy S, Ericsson G, Ronchi E, Sangaroon S, Akers R, Fitzgerald I, Cullen A, Weiszflog M. A neutron camera system for MAST. Rev Sci Instrum 2010; 81:10D315. [PMID: 21033841 DOI: 10.1063/1.3479038] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A prototype neutron camera has been developed and installed at MAST as part of a feasibility study for a multichord neutron camera system with the aim to measure the spatial and time resolved 2.45 MeV neutron emissivity profile. Liquid scintillators coupled to a fast digitizer are used for neutron/gamma ray digital pulse shape discrimination. The preliminary results obtained clearly show the capability of this diagnostic to measure neutron emissivity profiles with sufficient time resolution to study the effect of fast ion loss and redistribution due to magnetohydrodynamic activity. A minimum time resolution of 2 ms has been achieved with a modest 1.5 MW of neutral beam injection heating with a measured neutron count rate of a few 100 kHz.
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Affiliation(s)
- M Cecconello
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala, Sweden.
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22
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Murari A, Angelone M, Bonheure G, Cecil E, Craciunescu T, Darrow D, Edlington T, Ericsson G, Gatu-Johnson M, Gorini G, Hellesen C, Kiptily V, Mlynar J, Perez von Thun C, Pillon M, Popovichev S, Syme B, Tardocchi M, Zoita VL. New developments in the diagnostics for the fusion products on JET in preparation for ITER (invited). Rev Sci Instrum 2010; 81:10E136. [PMID: 21061488 DOI: 10.1063/1.3502038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Notwithstanding the advances of the past decades, significant developments are still needed to satisfactorily diagnose “burning plasmas.” D–T plasmas indeed require a series of additional measurements for the optimization and control of the configuration: the 14 MeV neutrons, the isotopic composition of the main plasma, the helium ash, and the redistribution and losses of the alpha particles. Moreover a burning plasma environment is in general much more hostile for diagnostics than purely deuterium plasmas. Therefore, in addition to the development and refinement of new measuring techniques, technological advances are also indispensable for the proper characterization of the next generation of devices. On JET an integrated program of diagnostic developments, for JET future and in preparation for ITER, has been pursued and many new results are now available. In the field of neutron detection, the neutron spectra are now routinely measured in the energy range of 1–18 MeV by a time of flight spectrometer and they have allowed studying the effects of rf heating on the fast ions. A new analysis method for the interpretation of the neutron cameras measurements has been refined and applied to the data of the last trace tritium campaign (TTE). With regard to technological upgrades, chemical vapor deposition diamond detectors have been qualified both as neutron counters and as neutron spectrometers, with a potential energy resolution of about one percent. The in situ calibration of the neutron diagnostics, in preparation for the operation with the ITER-like wall, is also promoting important technological developments. With regard to the fast particles, for the first time the temperature of the fast particle tails has been obtained with a new high purity Germanium detector measuring the gamma emission spectrum from the plasma. The effects of toroidal Alfven eigenmodes modes and various MHD instabilities on the confinement of the fast particles have been determined with a combination of gamma ray cameras, neutral particle analyzers, scintillator probe, and Faraday cups. From a more technological perspective, various neutron filters have been tested to allow measurement of the gamma ray emission also at high level of neutron yield.
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Affiliation(s)
- A Murari
- JET-EFDA, Culham Science Centre, OX14 3DB, Abingdon, United Kingdom
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23
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Hellesen C, Andersson Sundén E, Conroy S, Ericsson G, Eriksson J, Gatu Johnson M, Weiszflog M. Neutron spectroscopy results of JET high-performance plasmas and extrapolations to DT performance. Rev Sci Instrum 2010; 81:10D337. [PMID: 21058461 DOI: 10.1063/1.3502326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In a fusion reactor with high energy gain, the fusion power will be mainly thermonuclear (THN). Measurements of the THN neutron rate are a good performance indicator of a fusion plasma, requiring neutron emission spectroscopy (NES) measurements to distinguish thermal and nonthermal contributions. We report here on recent NES results from JET high-performance plasmas with high fractions (about 65%) of THN emission. The analysis is made with a framework for analyzing NES data, taking into account THN reactions and beam-target reactions. The results are used to extrapolate to the equivalent DT rates. Finally, we discuss the applicability of using NES in the deuterium phase of ITER, both for the extrapolations to ITER’s future DT performance as well as for the measurements of confined energetic ions.
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Affiliation(s)
- C Hellesen
- JET-EFDA, Culham Science Centre, OX14 3DB Abingdon, United Kingdom
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24
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Korsholm SB, Stejner M, Conroy S, Ericsson G, Gorini G, Tardocchi M, von Hellermann M, Jaspers RJE, Lischtschenko O, Delabie E, Bindslev H, Furtula V, Leipold F, Meo F, Michelsen PK, Moseev D, Nielsen SK, Salewski M. Development of novel fuel ion ratio diagnostic techniques. Rev Sci Instrum 2010; 81:10D323. [PMID: 21033847 DOI: 10.1063/1.3460634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
To overcome the challenge of measuring the fuel ion ratio in the core (ρ<0.3) of ITER, a coordinated effort aiming at developing diagnostic techniques has been initiated. The investigated techniques are novel uses or further development of existing methods such as charge exchange recombination spectrometry, neutron spectrometry, and collective Thomson scattering. An overview of the work on the three diagnostic techniques is presented.
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Affiliation(s)
- S B Korsholm
- Association EURATOM-Risø DTU, 4000 Roskilde, Denmark.
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25
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Ericsson G, Conroy S, Gatu Johnson M, Andersson Sundén E, Cecconello M, Eriksson J, Hellesen C, Sangaroon S, Weiszflog M. Neutron spectroscopy as a fuel ion ratio diagnostic: lessons from JET and prospects for ITER. Rev Sci Instrum 2010; 81:10D324. [PMID: 21058455 DOI: 10.1063/1.3502323] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The determination of the fuel ion ratio n(t)/n(d) in ITER is required at a precision of 20%, time resolution of 100 ms, spatial resolution of a/10, and over a range of 0.01<n(T)/n(D)<10. We use simplified but realistic Monte Carlo models of ITER to assess the possibility to use neutron emission spectroscopy (NES) for such measurements. We show that NES meets the requirements for ion temperatures T(i)>6 keV and for n(T)/n(D)<0.6. A crucial issue is the signal-to-background situation in the measurement of the weak 2.5 MeV emission from DD reactions in the presence of a background of scattered 14 MeV DT neutrons. Important experimental input and corroboration for this assessment are presented from the time-of-flight neutron spectrometer at JET where the presence of a strong component of backscattered neutrons is observed. Neutron emission components on ITER due to beam-thermal and tritium-tritium reactions can further enhance the prospects for NES.
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Affiliation(s)
- G Ericsson
- Department of Physics and Astronomy, Uppsala University (EURATOM-VR Association), SE-75120 Uppsala, Sweden.
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26
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Gatu Johnson M, Andersson Sundén E, Cecconello M, Conroy S, Ericsson G, Eriksson J, Gorini G, Hellesen C, Kiptily V, Nocente M, Sangaroon S, Sharapov SE, Tardocchi M, van Eester D, Weiszflog M. Neutron spectrometry of JET discharges with ICRH-acceleration of helium beam ions. Rev Sci Instrum 2010; 81:10D336. [PMID: 21058459 DOI: 10.1063/1.3502316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Recent experiments at JET aimed at producing 4He ions in the MeV range through third harmonic ion cyclotron resonance heating (ICRH) acceleration of 4He beams in a 4He dominated plasma. MeV range D was also present through parasitic ICRH absorption on residual D. In this contribution, we analyze TOFOR neutron spectrometer data from these experiments. A consistent description of the data is obtained with d(d,n)3He and 9Be(α,n)12C neutron components calculated using Stix distributions for the fast D and 4He, taking finite Larmor radius effects into account and with a ICRH power partition of P(D)(RF) = 0.01×P(4He)(RF), in agreement with TOMCAT simulations.
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Affiliation(s)
- M Gatu Johnson
- JET-EFDA, Culham Science Centre, OX14 3DB, Abingdon, United Kingdom.
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27
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Sjöstrand H, Andersson Sundén E, Conroy S, Ericsson G, Gatu Johnson M, Giacomelli L, Gorini G, Hellesen C, Hjalmarsson A, Popovichev S, Ronchi E, Tardocchi M, Weiszflog M. Gain stabilization control system of the upgraded magnetic proton recoil neutron spectrometer at JET. Rev Sci Instrum 2009; 80:063505. [PMID: 19572466 DOI: 10.1063/1.3109682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Burning plasma experiments such as ITER and DEMO require diagnostics capable of withstanding the harsh environment generated by the intense neutron flux and to maintain stable operating conditions for times longer than present day systems. For these reasons, advanced control and monitoring (CM) systems will be necessary for the reliable operation of diagnostics. This paper describes the CM system of the upgraded magnetic proton recoil neutron spectrometer installed at the Joint European Torus focusing in particular on a technique for the stabilization of the gain of the photomultipliers coupled to the neutron detectors. The results presented here show that this technique provides good results over long time scales. The technique is of general interest for all diagnostics that employ scintillators coupled to photomultiplier tubes.
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Affiliation(s)
- Henrik Sjöstrand
- Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, 75120 Uppsala, Sweden
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28
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Hellesen C, Sundén EA, Conroy S, Ericsson G, Giacomelli L, Hjalmarsson A, Johnsson MG, Källne J, Ronchi E, Weiszflog M, Ballabio L, Gorini G, Tardocchi M, Voitsekhovitch I. Validating TRANSP simulations using neutron emission spectroscopy with dual sight lines. Rev Sci Instrum 2008; 79:10E510. [PMID: 19068504 DOI: 10.1063/1.2965017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A method to generate modeled neutron spectra from bulk and fast ion distributions simulated by TRANSP has been developed. In this paper, modeled data generated from fuel ion distributions modeled with TRANSP is compared to measured data from two neutron spectrometers with different lines of sight; TOFOR with a radial one and the MPRu with a tangential one. The information obtained from the analysis of the measured neutron spectra such as the relative intensity of the emission from different ion populations places additional constraints on the simulation and can be used to adjust the parameters of the simulation.
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Affiliation(s)
- C Hellesen
- VR, Uppsala University, SE-75120 Uppsala, Sweden.
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29
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Giacomelli L, Hjalmarsson A, Källne J, Hellesen C, Tardocchi M, Gorini G, Van Eester D, Lerche E, Johnson T, Kiptily V, Conroy S, Andersson Sundén E, Ericsson G, Gatu Johnson M, Sjöstrand H, Weiszflog M. Neutron emission spectroscopy results for internal transport barrier and mode conversion ion cyclotron resonance heating experiments at JET. Rev Sci Instrum 2008; 79:10E514. [PMID: 19068506 DOI: 10.1063/1.2965009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The effect of ion cyclotron resonance heating (ICRH) on (3He)D plasmas at JET was studied with the time of flight optimized rate (TOFOR) spectrometer dedicated to 2.5 MeV dd neutron measurements. In internal transport barrier (ITB) plasma experiments with large 3He concentrations (X(3He)>15%) an increase in neutron yield was observed after the ITB disappeared but with the auxiliary neutral beam injection and ICRH power still applied. The analysis of the TOFOR data revealed the formation of a high energy (fast) D population in this regime. The results were compared to other mode conversion experiments with similar X(3He) but slightly different heating conditions. In this study we report on the high energy neutron tails originating from the fast D ions and their correlation with X(3He) and discuss the light it can shed on ICRH-plasma power coupling mechanisms.
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Affiliation(s)
- L Giacomelli
- Department of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden.
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Ronchi E, Conroy S, Sundén EA, Ericsson G, Hjalmarsson A, Hellesen C, Johnson MG, Weiszflog M. A neural networks framework for real-time unfolding of neutron spectroscopic data at JET. Rev Sci Instrum 2008; 79:10E513. [PMID: 19068505 DOI: 10.1063/1.2953492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A determination of fast ion population parameters such as intensity and kinetic temperature is important for fusion reactors. This becomes more challenging with finer time resolution of the measurements, since the limited data in each time slice cause increasing statistical variations in the data. This paper describes a framework using Bayesian-regularized neural networks (NNs) designed for such a task. The method is applied to the TOFOR 2.5 MeV fusion neutron spectrometer at JET. NN training data are generated by random sampling of variables in neutron spectroscopy models. Ranges and probability distributions of the parameters are chosen to match the experimental data. Results have shown good performance both on synthetic and experimental data. The latter was assessed by statistical considerations and by examining the robustness and time consistency of the results. The regularization of the training algorithm allowed for higher time resolutions than simple forward methods. The fast execution time makes this approach suitable for real-time analysis with a time resolution limit in the microsecond time scale.
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Affiliation(s)
- E Ronchi
- VR, Uppsala University, SE-75120 Uppsala, Sweden.
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31
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Jones TTC, Brennan D, Pearce RJH, Stork D, Zastrow KD, Balshaw N, Bell AC, Bertalot L, Boyer H, Butcher PR, Challis CD, Ciric D, Clarke R, Conroy S, Darke AC, Davies N, Edlington T, Ericsson G, Gibbons C, Hackett LJ, Haupt T, Hitchin M, Kaye AS, King R, Kiptily VG, Knipe S, Lawrence G, Lobel R, Mason A, Morgan PD, Patel B, Popovichev S, Stamp M, Surrey E, Terrington A, Worth L, Young D. Technical and Scientific Aspects of the JET Trace-Tritium Experimental Campaign. Fusion Science and Technology 2005. [DOI: 10.13182/fst05-a922] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- T T C Jones
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - D Brennan
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - R J H Pearce
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - D Stork
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - K-D Zastrow
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - N Balshaw
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - A C Bell
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - L Bertalot
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
- Associazione EURATOM/ENEA sulla Fusione, Frascati, Italy
| | - H Boyer
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - P R Butcher
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - C D Challis
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - D Ciric
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - R Clarke
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - S Conroy
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
- EURATOM/VR Association, INF, Uppsala University, Uppsala, Sweden
| | - A C Darke
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - N Davies
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - T Edlington
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - G Ericsson
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
- EURATOM/VR Association, INF, Uppsala University, Uppsala, Sweden
| | - C Gibbons
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - L J Hackett
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - T Haupt
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - M Hitchin
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - A S Kaye
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - R King
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - V G Kiptily
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - S Knipe
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - G Lawrence
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - R Lobel
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - A Mason
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - P D Morgan
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - B Patel
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - S Popovichev
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - M Stamp
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - E Surrey
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - A Terrington
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - L Worth
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
| | - D Young
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB UK
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32
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Sousa J, Batista A, Combo A, Pereira R, Cruz N, Carvalho P, Varandas C, Conroy S, Ericsson G, Källne J. A PCI time digitizer for the new JET time-of-flight neutron spectrometer. Fusion Engineering and Design 2004. [DOI: 10.1016/j.fusengdes.2004.04.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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33
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Ericsson G, Heberlein TA. “Jägare talar naturens språk” (Hunters speak nature's language): A comparison of outdoor activities and attitudes toward wildlife among Swedish hunters and the general public. EUR J WILDLIFE RES 2002. [DOI: 10.1007/bf02192422] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Winter R, Gudmundsson P, Ericsson G, Willenheimer R. Left ventricular early diastolic inflow velocity and atrial ventricular plane downward velocity: useful parameters to test diastolic function in clinical practice? Diastolic parameters tested in a clinical setting. Eur J Echocardiogr 2001; 2:126-31. [PMID: 11882439 DOI: 10.1053/euje.2001.0083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
AIMS To study the clinical value of the colour-M-mode slope of the early diastolic left ventricular filling phase (Vp) and the early diastolic downward M-mode slope of the left atrioventricular plane displacement (EDS), compared with diastolic function assessed by traditional Doppler evaluation. METHODS AND RESULTS In 65 consecutive patients EDS and Vp were compared with a four-degree traditional diastolic function classification, based on pulsed Doppler assessment of the early to atrial transmitral flow ratio (E/A), the E-wave deceleration time (Edt), and the systolic to diastolic (S/D) pulmonary venous inflow ratio. Vp (P=0.006) and EDS (P=0.045) were related to traditional diastolic function (Kruskal--Wallis analysis). EDS showed a trend brake between the moderate and severe diastolic dysfunction groups by traditional Doppler evaluation. Vp and EDS correlated weakly in simple linear regression analysis (r=0.33). Vp and EDS discriminated poorly between normal and highly abnormal diastolic function. CONCLUSIONS Vp and EDS were significantly related to diastolic function by traditional Doppler evaluation. They were, however, not useful as single parameters of left ventricular diastolic function due to a small difference between normal and highly abnormal values, allowing for little between-measurement variability. Consequently, these methods for the evaluation of left ventricular diastolic function do not add significantly to traditional Doppler evaluation.
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Affiliation(s)
- R Winter
- Department of Cardiology, Malmö University Hospital, Lund University, Malmö, Sweden
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35
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Kallne J, Ballabio L, Frenje J, Conroy S, Ericsson G, Tardocchi M, Traneus E, Gorini G. Observation of the alpha particle "Knock-On" neutron emission from magnetically confined DT fusion plasmas. Phys Rev Lett 2000; 85:1246-1249. [PMID: 10991523 DOI: 10.1103/physrevlett.85.1246] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2000] [Indexed: 05/23/2023]
Abstract
Suprathermal fuel ions from alpha-particle knock-on collisions in fusion DT plasmas are predicted to cause a weak feature in the neutron spectrum of d+t-->alpha+n. The knock-on feature has been searched for in the neutron emission of high ( >1 MW) fusion-power plasmas produced at JET and was found using a magnetic proton recoil type neutron spectrometer of high performance. Measurement and predictions agree both in absolute amplitude and in plasma-parameter dependence, supporting the interpretation and model. Moreover, the results provide input to projecting alpha-particle diagnostics for future self-heated fusion plasmas.
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Affiliation(s)
- J Kallne
- Department of Neutron Research, Uppsala University, EURATOM-NFR Association, Uppsala, Sweden
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Elmér R, Berg M, Carlén L, Jakobsson B, Norén B, Oskarsson A, Ericsson G, Julien J, Thorsteinsen T, Guttormsen M, Lovhoiden G, Bellini V, Grosse E, Müntz C, Senger P, Westerberg L. K+ Emission in Symmetric Heavy Ion Reactions at Subthreshold Energies. Phys Rev Lett 1996; 77:4884-4886. [PMID: 10062659 DOI: 10.1103/physrevlett.77.4884] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Wratten SD, Mead-Briggs M, Gettinby G, Ericsson G, Baggott DG. An evaluation of the potential effects of ivermectin on the decomposition of cattle dung pats. Vet Rec 1993; 133:365-71. [PMID: 8256422 DOI: 10.1136/vr.133.15.365] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The parasiticide ivermectin has been administered to domestic livestock since 1981 to control internal and external parasites, including insects; some of the ivermectin is excreted unchanged in faeces. Concerns over the effects of ivermectin on dung-utilising insect populations and the potential for consequent persistence of dung on pastures have been raised. This paper presents the results of a study over two grazing seasons of the rate of decomposition of cattle dung pats exposed to normal environmental influences. The cattle had been treated at therapeutic levels with either an injectable or a sustained release bolus formulation of ivermectin. It was concluded that the rate of decomposition of the dung pats, the extent of their avoidance by the cows, the organic matter content of the soil and the populations of earthworms in the pastures were not affected by the use of ivermectin.
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Affiliation(s)
- S D Wratten
- Department of Biology, School of Biological Sciences, University of Southampton
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Armstrong TA, Bocquet JP, Ericsson G, Johansson T, Krogulski T, Lewis RA, Malek F, Maurel M, Monnand E, Mougey J, Nifenecker H, Passaneau J, Perrin P, Polikanov SM, Rey-Campagnolle M, Ristori C, Smith GA, Tibell G. Fission of heavy hypernuclei formed in antiproton annihilation. Phys Rev C Nucl Phys 1993; 47:1957-1969. [PMID: 9968650 DOI: 10.1103/physrevc.47.1957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Westlind-Danielsson A, Ericsson G, Sandell L, Elinder F, Arhem P. High concentrations of the neuroleptic remoxipride block voltage-activated Na+ channels in central and peripheral nerve membranes. Eur J Pharmacol 1992; 224:57-62. [PMID: 1333408 DOI: 10.1016/0014-2999(92)94818-g] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The actions of the neuroleptic compounds remoxipride, haloperidol and (-)-sulpiride on Na+ and K+ ion current flow were examined in rat CNS and frog PNS, using 86Rb+ ion flux and voltage-clamp techniques, respectively. By combining veratridine and high K(+)-evoked 86Rb+ efflux, it was determined that remoxipride blocked Na+ current flow in a concentration-dependent fashion in tissue pieces from either cerebral cortex or striatum (IC50 approximately 20 microM), leaving K+ current flow virtually unaffected. Similarly, haloperidol concentration dependently blocked Na+ current flow in both tissues (IC50 approximately 50 microM). (-)-Sulpiride did not have a significant effect. Direct actions of the compounds on voltage-gated Na+ and K+ channels were determined in voltage-clamp experiments. The findings confirmed the results of the ion flux measurements in that remoxipride (Kd approximately 300 microM) and haloperidol (Kd approximately 1.5 microM) reduced mainly the Na+ current, having little effect on the K+ current, whereas (-)-sulpiride did not have a measurable action. The relatively high concentrations of remoxipride or haloperidol needed to alter the Na+ current makes it unlikely that these actions are of importance at clinically relevant doses.
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Chen B, Armstrong TA, Lewis RA, Newton R, Smith GA, Bocquet JP, Malek F, Nifenecker H, Maurel M, Monnand E, Perrin P, Ristori C, Ericsson G, Johansson T, Tibell G, Rey-Campagnolle M, Polikanov S, Krogulski T, Mougey J. Neutron yields and angular distributions produced in antiproton annihilation at rest in uranium. Phys Rev C Nucl Phys 1992; 45:2332-2337. [PMID: 9967995 DOI: 10.1103/physrevc.45.2332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
Vocal abuse is the best-known etiological factor in contact ulcer. Other factors, such as hiatus hernia and gastroesophageal reflux have been discussed. A 12-year study of 58 male patients (mean age 52 years) with present or previous contact ulcers, is reported. Forty-three patients were investigated with esophageal function tests, ie, esophageal manometry including pH monitoring, acid-perfusion test, and acid-clearing test. Esophageal dysfunction was found in 74% which is significantly higher than the 30% found in the general population.
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Abstract
At the Hospital of Physical Medicine, Hornbaek, we analysed in retrospect 52 cases of myositis ossificans circumscripta (MOC) among 605 patients with para/tetraplegia. MOC proved significantly more common after total than after subtotal spinal cord injuries. MOC was not observed in any case above the motor level of the spinal cord lesion. This neurological relationship appears to "explain" the finding that MOC is more common in para/tetraplegia of traumatic origin (more complete spinal cord lesions) than among those caused by slipped discs or tumours. Twenty-five per cent of the patients ended up with fairly mild and 12% with more severe hip contractures, the latter causing recurrent, contralateral decubital ulcers over the ischial tuberosity and protracted hospitalization. To aid diagnosis, the authors suggest a simple programme for all para/tetraplegics. In our opinion, routine X-ray examination is not necessary. Intensified research into the causative factors and treatment is needed, not only to facilitate these patients' social adaptation, but also for socio-economic reasons.
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Atterhög JH, Ekelund LG, Ericsson G, Ahlborg B. Significance of primary T wave aberrations in the electrocardiogram of asymptomatic young men. Part II. Working capacity and anthropometric data. Ups J Med Sci 1980; 85:179-91. [PMID: 7245440 DOI: 10.3109/03009738009179186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Fifty-one healthy men, 18 - 19 years of age, with "organic" T wave aberrations (group T) were compared to 112 controls of the same age with normal electrocardiograms (Group A + B). Group T had increased heart rate and higher systolic and diastolic blood pressures. Their lower physical work capacity could be "explained" in multivariate analysis by their shorter height, smaller heart volume and lower total hemoglobin (the latter not constituting a significant difference between the groups). Multiple regression analysis indicated that differences in heart rate, systolic blood pressure and blood volumes explained differences between subjects with and without primary T wave aberrations. These variables are all influenced by changes in sympathetic discharge, whereas no variable representing performance or body dimensions contributed to the explanation.
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Atterhög JH, Ekelund LG, Ericsson G, Ahlborg B. Significance of primary T wave aberrations in the electrocardiogram of asymptomatic young men. Part 1. Electrocardiographic data. Ups J Med Sci 1980; 85:125-42. [PMID: 7245436 DOI: 10.3109/03009738009179180] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The electrocardiogram (ECG) at rest and during orthostasis and exercise in 51 healthy men 18-19 years of age without history or symptoms of heart disease, but with T wave aberrations in the ECG (group T) were compared to the normal ECGs of 112 controls of the same age. These aberrations (which literature suggests to be due to organic heart disease) consisted of either a notch in the T wave, especially in the midprecordial leads, that sometimes became inverted, or a low T wave without concomitant ST depression. The T wave aberrations at rest in group T were similar to what 25% of the controls evidenced during orthostasis (group B). Both group T and group B had signs of increased sympathetic tone at rest with a higher heart rate and systolic blood pressure than did the subjects with normal ECG both at rest and during orthostasis. These T wave aberrations disappeared for the majority during exercise. Both group T and group B had prolonged QTc intervals. Group T had increased R wave amplitudes which did not correlate to the severity of the T wave aberration or to systolic blood pressure. Our opinion is that primary T wave aberrations in the majority of these young men were because of increased sympathetic tone.
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Ahlborg B, Atterhög JH, Ekelund LG, Ericsson G. Pre-excitation in young men. Incidence, some anthropometric data and physical work capacity. Acta Med Scand 1974; 196:275-8. [PMID: 4429001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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46
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Ericsson G, Hammarberg B. [A study on language development of 4-year-old children in Stockholm]. Lakartidningen 1971; 68:6058-60. [PMID: 5159263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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