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  • 201.
    Dimitriou, Paraskevi
    et al.
    IAEA, Vienna.
    Hambsch, Franz-JosefEuropean Commission Joint Research Centre - JRC Directorate G – Nuclear Safety & Security, Geel, Belgium.Pomp, StephanUppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Fission Product Yields Data Current status and perspectives: Summary report of an IAEA Technical meeting2016Proceedings (redaktörskap) (Övrigt vetenskapligt)
    Abstract [en]

    A Technical Meeting on Fission Product Yields Data: current status and perspectives, was held from 23 to 26 May 2016, at the IAEA, Vienna. The purpose of the meeting was to review the current status of Fission Product Yield data, and discuss the progress in measurements, theories, evaluation and covariances. The presentations, technical discussions and recommendations of the meeting are given in detail in this summary report.

  • 202.
    Drenik, A.
    et al.
    Max Planck Inst Plasma Phys, Garching, Germany; Jozef Stefan Inst, Ljubljana, Slovenia.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, Nataliia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Natl Ctr Nucl Res NCBJ, Otwock, Poland.
    Analysis of the outer divertor hot spot activity in the protection video camera recordings at JET2019Ingår i: Fusion engineering and design, ISSN 0920-3796, E-ISSN 1873-7196, Vol. 139, s. 115-123Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hot spots on the divertor tiles at JET result in overestimation of the tile surface temperature which causes unnecessary termination of pulses. However, the appearance of hot spots can also indicate the condition of the divertor tile surfaces. To analyse the behaviour of the hot spots in the outer divertor tiles of JET, a simple image processing algorithm is developed. The algorithm isolates areas of bright pixels in the camera image and compares them to previously identified hot spots. The activity of the hot spots is then linked to values of other signals and parameters in the same time intervals. The operation of the detection algorithm was studied in a limited pulse range with high hot spot activity on the divertor tiles 5, 6 and 7. This allowed us to optimise the values of the controlling parameters. Then, the wider applicability of the method has been demonstrated by the analysis of the hot spot behaviour in a whole experimental campaign.

  • 203.
    Duan, Junfeng
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Furhter analysis about predicted levels of Be9 based on neutron double differential cross sections at Ep=18 MeV2012Ingår i: Proceedings of the 13th International Conference of Nuclear Reaction Mechanisms / [ed] Edited by Francesco Cerutti, Mark Chadwick, Alfredo Ferrari, and Toshihiko Kawano, with Simone Bottoni and Luna Pellegri, 2012, s. 81-88Konferensbidrag (Refereegranskat)
  • 204.
    Duan, Junfeng
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Pomp, Stephan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Alhassan, Erwin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gustavsson, Cecillia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Österlund, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Koning, Arjan
    Rochman, Dimitri
    Uncertainty Study of Nuclear Model Parameters for the n+Fe-56 Reactions in the Fast Neutron Region below 20 MeV2014Ingår i: Nuclear Data Sheets, ISSN 0090-3752, E-ISSN 1095-9904, Vol. 118, s. 346-348Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this work we study the uncertainty of nuclear model parameters for neutron induced Fe-56 reactions in the fast neutron region by using the Total Monte Carlo method. We perform a large number of TALYS runs and compare the calculated results with the experimental data of the cross sections to obtain the uncertainties of the model parameters. Based on the derived uncertainties another 1000 TALYS runs have been performed to create random cross section files. For comparison with the experimental data we calculate a weighted chi(2) value for each random file as well as the ENDF/B-VII. 1, JEFF-3.1, JENDL-4.0 and CENDL-3.1 data libraries. Furthermore, we investigate the optical model parameters correlation obtained by way of this procedure.

  • 205.
    Dumont, R. J.
    et al.
    CEA, IRFM, F-13108 St Paul Les Durance, France.
    Mailloux, J.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Aslanyan, V
    MIT, PSFC, 175 Albany St, Cambridge, MA 02039 USA.
    Baruzzo, M.
    Consorzio RFX, Corso Stati Uniti 4, I-35127 Padua, Italy.
    Challis, C. D.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Coffey, I
    Queens Univ, Dept Pure & Appl Phys, Belfast BT7 1NN, Antrim, North Ireland.
    Czarnecka, A.
    Inst Plasma Phys & Laser Microfus, Hery St 23, PL-00908 Warsaw, Poland.
    Delabie, E.
    Oak Ridge Natl Lab, Oak Ridge, TN USA.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Faustin, J.
    Ecole Polytech Fed Lausanne, SPC, CH-1015 Lausanne, Switzerland.
    Ferreira, J.
    Univ Lisbon, IST, Inst Plasmas & Fusao Nucl, Lisbon, Portugal.
    Fitzgerald, M.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Garcia, J.
    CEA, IRFM, F-13108 St Paul Les Durance, France.
    Giacomelli, L.
    Univ Milano Bicocca, Piazza Sci 3, I-20126 Milan, Italy.
    Giroud, C.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Hawkes, N.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Jacquet, Ph
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Joffrin, E.
    CEA, IRFM, F-13108 St Paul Les Durance, France.
    Johnson, T.
    KTH, EES, Fus Plasma Phys, SE-10044 Stockholm, Sweden.
    Keeling, D.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    King, D.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Kiptily, V
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Lomanowski, B.
    Aalto Univ, POB 14100, FIN-00076 Aalto, Finland.
    Lerche, E.
    Ass EUROFUS Belgian State, LPP ERM KMS, TEC Partner, Brussels, Belgium.
    Mantsinen, M.
    Barcelona Supercomp Ctr, Barcelona, Spain;ICREA, Barcelona, Spain.
    Meneses, L.
    Univ Lisbon, IST, Inst Plasmas & Fusao Nucl, Lisbon, Portugal.
    Menmuir, S.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    McClements, K.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Moradi, S.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Nabais, F.
    Univ Lisbon, IST, Inst Plasmas & Fusao Nucl, Lisbon, Portugal.
    Nocente, M.
    Univ Milano Bicocca, Piazza Sci 3, I-20126 Milan, Italy.
    Patel, A.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Patten, H.
    Ecole Polytech Fed Lausanne, SPC, CH-1015 Lausanne, Switzerland.
    Puglia, P.
    Ecole Polytech Fed Lausanne, SPC, CH-1015 Lausanne, Switzerland.
    Scannell, R.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Sharapov, S.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Solano, E. R.
    CIEMAT, Lab Nacl Fus, Madrid, Spain.
    Tsalas, M.
    ITER Org, Route Vinon Sur Verdon, F-13067 St Paul Les Durance, France;FOM Inst DIFFER, NL-3430 BE Nieuwegein, Netherlands.
    Vallejos, P.
    KTH, EES, Fus Plasma Phys, SE-10044 Stockholm, Sweden.
    Weisen, H.
    Ecole Polytech Fed Lausanne, SPC, CH-1015 Lausanne, Switzerland.
    Scenario development for the observation of alpha-driven instabilities in JET DT plasmas2018Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 58, nr 8, artikel-id 082005Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In DT plasmas, toroidal Alfven eigenmodes (TAEs) can be made unstable by the alpha particles resulting from fusion reactions, and may induce a significant redistribution of fast ions. Recent experiments have been conducted in JET deuterium plasmas in order to prepare scenarios aimed at observing alpha-driven TAEs in a future JET DT campaign. Discharges at low density, large core temperatures associated with the presence of internal transport barriers and characterised by good energetic ion confinement have been performed. ICRH has been used in the hydrogen minority heating regime to probe the TAE stability. The consequent presence of MeV ions has resulted in the observation of TAEs in many instances. The impact of several key parameters on TAE stability could therefore be studied experimentally. Modeling taking into account NBI and ICRH fast ions shows good agreement with the measured neutron rates, and has allowed predictions for DT plasmas to be performed.

  • 206.
    Duran, Ignacio
    et al.
    Universidade de Santiago de Compostela (USC), Santiago de Compostela, Spain.
    Ventura, A.
    Istituto Nazionale di Fisica Nucleare, Bologna, Italy.
    Lo Meo, S.
    Istituto Nazionale di Fisica Nucleare, Bologna, Italy; Agenzia Nazionale per le Nuove Tecnologie, Bologna, Italy.
    Tarrio, Diego
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Tassan-Got, L.
    Centre National de la Recherche Scientifique/IN2P3 - IPN-Orsay, France.
    Paradela, C.
    European Commission JRC - IRMM, Geel, Belgium.
    On the search for a (n,f) cross-section reference at intermediate energies2017Ingår i: ND 2016: INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY / [ed] Plompen, A; Hambsch, FJ; Schillebeeckx, P; Mondelaers, W; Heyse, J; Kopecky, S; Siegler, P; Oberstedt, S, Les Ulis: EDP Sciences, 2017, Vol. 146, artikel-id 02032Konferensbidrag (Refereegranskat)
    Abstract [en]

    The (n,f) cross-sections proposed as references by the IAEA for 235U, 238U and 209Bi are compared with a new analysis that combines the measurements performed at CERN-n_TOF of their cross-section ratios with new calculations done using Monte Carlo codes based on phenomenological models INCL+ +, GEMINI+ +, and ABLA07. The calculations are cross-checked with those for the (p,f) reactions, where experimental values are available. We have evaluated in this way the (n,f) cross sections for 238U, 235U and 209Bi, in the intermediate energy region going from 190 MeV to 2 GeV. Our results definitively discard the JENDL/HE-2007 evaluations above 300 MeV, falling inside the confidence corridor proposed by IAEA but for the points around 300–400 MeV where a discrepancy is to be noticed.

  • 207.
    Dzysiuk, Nataliia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Ericsson
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Modelling the neutron and gamma fluences at KR22013Rapport (Övrigt vetenskapligt)
  • 208.
    Dzysiuk, Nataliia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Design of a Backscatter 14-MeV Neutron Time-of-Flight Spectrometer for Experiments at ITER2014Ingår i: Fusion Reactor Diagnostics / [ed] Gorini, G; Orsitto, FP; Sozzi, C; Tardocchi, M, 2014, Vol. 1612, s. 145-148Konferensbidrag (Refereegranskat)
    Abstract [en]

    Neutron energy spectrometry diagnostics play an important role in present-day experiments related to fusion energy research. Measurements and thorough analysis of the neutron emission from the fusion plasma give information on a number of basic fusion performance quantities, on the condition of the neutron source and plasma behavior. Here we discuss the backscatter Time-of-Flight (bTOF) spectrometer concept as a possible instrument for performing high resolution measurements of 14 MeV neutrons. The instrument is based on two sets of scintillators, a first scatterer exposed to a collimated neutron beam and a second detector set placed in the backward direction. The scintillators of the first set are enriched in deuterium to achieve neutron backscattering. The energy resolution and efficiency of a bTOF instrument have been determined for various geometrical configurations. A preliminary design of optimal geometry for the two scintillator sets has been obtained by Monte Carlo simulations based on the MCNPX code.

  • 209.
    Dzysiuk, Nataliia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Kadenko, I.
    Gressier, V.
    Koning, A. J.
    Cross section measurement of the Tb-159(n, gamma)Tb-160 nuclear reaction2015Ingår i: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 936, s. 6-16Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The cross section of the Tb-159(n, gamma)Tb-160 reaction was measured in four mono-energetic neutron fields of energy 3.7, 4.3, 5.4, and 6.85 MeV, respectively, with the activation technique applied to metal discs of natural composition. To ensure an acceptable precision of the results all major sources of uncertainties were taken into account. Calculations of detector efficiency, incident neutron spectrum and correction factors were performed with the Monte Carlo code (MCNPX), whereas theoretical excitation functions were calculated with the TALYS-1.2 code and compared to the experimental cross section values. This paper presents both measurements and calculation leading to the cross section values.

  • 210.
    Eilers, Gerriet
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Persson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gustavsson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ryderfors, Linus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Mukhtar, Emad
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Salehpour, Mehran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    The Radiocarbon Intracavity Optogalvanic Spectroscopy Setup at Uppsala2013Ingår i: Radiocarbon, ISSN 0033-8222, E-ISSN 1945-5755, Vol. 55, nr 3-4, s. 237-250Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Accelerator mass spectrometry (AMS) is by far the predominant technology deployed for radiocarbon tracer studies. Applications are widespread from archaeology to biological, environmental, and pharmaceutical sciences. In spite of its excellent performance, AMS is expensive and complicated to operate. Consequently, alternative detection techniques for 14C are of great interest, with the vision of a compact, user-friendly, and inexpensive analytical method. Here, we report on the use of intracavity optogalvanic spectroscopy (ICOGS) for measurements of the 14C/12C ratio. This new detection technique was developed by Murnick et al. (2008). In the infrared (IR) region, CO2 molecules have strong absorption coefficients. The IR-absorption lines are narrow in line width and shifted for different carbon isotopes. These properties can potentially be exploited to detect 14CO2, 13CO2, or 12CO2 molecules unambiguously. In ICOGS, the sample is in the form of CO2 gas, eliminating the graphitization step that h is required in most AMS labs. The status of the ICOGS setup in Uppsala is presented. The system is operational but not yet fully developed. Data are presented for initial results that illustrate the dependence of the optogalvanic signal on various parameters, such as background and plasma-induced changes in the sample gas composition.

  • 211. Elter, Zsolt
    et al.
    Caldeira Balkeståhl, Li
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Grape, Sophie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Geometry-based Variance Reduction in simulations of Passive Gamma Spectroscopy from Spent Nuclear Fuel2018Konferensbidrag (Övrigt vetenskapligt)
  • 212. Elter, Zsolt
    et al.
    Caldeira Balkeståhl, Li
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Grape, Sophie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Nuclear safeguards verification of modelled BWR fuel using a multivariate analysis approach2018Konferensbidrag (Övrigt vetenskapligt)
  • 213. Elter, Zsolt
    et al.
    Caldeira Balkeståhl, Li
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Grape, Sophie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Partial defect identification in PWR spent fuel using Passive Gamma Spectroscopy2018Konferensbidrag (Refereegranskat)
  • 214.
    Englund, Sven
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Grini, Sigbjorn
    Univ Oslo, Ctr Mat Sci & Nanotechnol, Dept Phys, Gaustdalleen 23 A, N-0316 Oslo, Norway.
    Donzel-Gargand, Olivier
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Paneta, Valentina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Kosyak, Volodymyr
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Primetzhofer, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Scragg, Jonathan J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Platzer Björkman, Charlotte
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    TiN Interlayers with Varied Thickness in Cu2ZnSnS(e)(4) Thin Film Solar Cells: Effect on Na Diffusion, Back Contact Stability, and Performance2018Ingår i: Physica Status Solidi (a) applications and materials science, ISSN 1862-6300, E-ISSN 1862-6319, Vol. 215, nr 23, artikel-id 1800491Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, interlayers with varied thickness of TiN between Cu2ZnSnS(e)(4) (CZTS(e)) absorbers and Mo on soda-lime glass substrates are investigated for CZTS(e) thin film solar cells. Na diffusion is analyzed using Secondary Ion Mass Spectrometry and it is found that the use of thick TiN interlayers facilitates Na diffusion into the absorbers. The CZTS(e)/TiN/Mo interfaces are scrutinized using Transmission Electron Microscopy (TEM) Electron Energy Loss Spectroscopy (EELS). It is found that diffusion of chalcogens present in the precursor occurs through openings, resulting from surface roughness in the Mo, in the otherwise chemically stable TiN interlayers, forming point contacts of MoS(e)(2). It is further established that both chalcogens and Mo diffuse along the TiN interlayer grain boundaries. Solar cell performance for sulfur-annealed samples improved with increased thickness of TiN, and with a 200 nm TiN interlayer, the solar cell performance is comparable to a typical Mo reference. Pure TiN bulk contacts are investigated and shown to work, but the performance is still inferior to the TiN interlayer back contacts. The use of thick TiN interlayers offers a pathway to achieve high efficiency CZTS(e) solar cells on highly inert back contacts.

  • 215.
    Englund, Sven
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik. Uppsala universitet.
    Paneta, Valentina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Primetzhofer, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ren, Yi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Donzel-Gargand, Olivier
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Larsen, Jes K
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Scragg, Jonathan J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Platzer Björkman, Charlotte
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Characterization of TiN back contact interlayers with varied thickness for Cu2ZnSn(S,Se)4 thin film solar cells2017Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 639, s. 91-97Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    TiN thin films have previously been used as intermediate barrier layers on Mo back contacts in CZTS(e) solar cells to suppress excessive reaction of the Mo in the annealing step. In this work, TiN films with various thickness (20, 50 and 200 nm) were prepared with reactive DC magnetron sputtering on Mo/SLG substrates and annealed, without CZTS(e) layers, in either S or Se atmospheres. The as-deposited references and the annealed samples were characterized with X-ray Photoelectron Spectroscopy, X-ray Diffraction, Time-of-Flight-Elastic Recoil Detection Analysis, Time-of-Flight-Medium-Energy Ion Scattering, Scanning Electron Microscopy and Scanning Transmission Electron Microscopy – Electron Energy Loss Spectroscopy. It was found that the as-deposited TiN layers below 50 nm show discontinuities, which could be related to the surface roughness of the Mo. Upon annealing, TiN layers dramatically reduced the formation of MoS(e)2, but did not prevent the sulfurization or selenization of Mo. The MoS(e)2 had formed near the discontinuities, both below and above the TiN layers. Another unexpected finding was that the thicker TiN layer increased the amount of Na diffused to the surface after anneal, and we suggest that this effect is related to the Na affinity of the TiN layers and the MoS(e)2 thickness.

  • 216.
    Ericsson, Göran
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Pomp, Stephan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Comments on the report" Indications of anomalous heat energy production in a reactor device containing hydrogen loaded nickel powder"[arXiv: 1305.3913] by G. Levi, E. Foschi, T. Hartman, B. Höistad, R. Pettersson, L. Tegner, H. EssenManuskript (preprint) (Övrigt vetenskapligt)
  • 217.
    Eriksson, Benjamin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Monte Carlo simulations of a back scatter time-of-flight neutron spectrometer for the purpose of concept testing.2018Studentarbete övrigt, 10 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The work focuses on Monte Carlo simulations for finding the optimal back scatter time-of-flight spectrometer design for concept testing at the NESSA facility at Uppsala University. The spectrometer consists of two scintillator detectors, D1 (placed in a neutron beam) and D2 (placed in front of D1), at some distance from each other. A fraction of the neutrons that impinge on D1 back scatter into D2 and information on the neutron energy distribution is acquired using the time-of-flight method. For the given constraints on geometry, resolution and efficiency a best resolution was found to be 6.6% with a corresponding efficiency of 1E-4 which gives a sufficient count rate for a neutron generator producing 1E+11 neutrons/s. In order to achieve a minimum of 10 000 counts/h with the same setup a D2 with an area of at least 7 cm^2 is required.

  • 218.
    Eriksson, Benjamin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Neutron field characterization using TFBCs and comparison to Monte Carlo simulations2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 219.
    Eriksson, Benjamin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Simulations of a back scatter time of flight neutron spectrometer for the purpose of concept testing at the NESSA facility.2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    A back scatter time of flight neutron spectrometer consisting of two scintillation detectors is simulated in Geant4 to examine whether it is possible to perform a proof of concept test at the NESSA facility at Uppsala University. An efficiency of ε = 2.45 · 10^-6 is shown to be large enough for a neutron generator intensity of 1.9 · 10^10 neutrons per second to achieve a minimal required signal count rate of 10000 counts per hour. A corresponding full width at half maximum energy resolution of 8.3% is found. The background in one of the detectors is simulated in MCNP and found to be a factor 62 larger than the signal for a given set of pulse height thresholds in the detectors. Measures to increase the signal to background ratio are discussed and an outlook for future work concerning testing the spectrometer at NESSA is presented.

  • 220.
    Eriksson, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Osäkerhetsanalys av PSA-resultat: Metodutveckling och parameterinventeringför osäkerhetsanalys av PSA-resultat2017Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This master thesis examines the possibility of performing asimplified uncertainty analysis on a probabilistic safety assessment(PSA) of the Oskarshamn 3 nuclear power plant. The aim of the thesiswas divided in two parts, first to examine the uncertainty parametersof a PSA-model for Oskarshamn 3 and the second part was to developand examine a simplified method of uncertainty analysis as comparedto a more regular method of Monte Carlo-simulation. The thesis ismostly concerned with examining the core damage frequency. Theexamination of uncertainty parameters showed that many parameterswere missing from the model and thus further investigation areneeded, if a full Monte Carlo is to be performed. The simplifiedmethod for uncertainty analysis that was developed consisted ofassuming a lognormal distribution for the frequency of basic eventsand then using the minimal cutset-list to calculate an approximationto the end distribution. The simplified method was then compared tothe Monte Carlo-analysis for Oskarshamn 2 for different MCS-lists anda preliminary uncertainty analysis was performed for Oskarshamn 3.

  • 221.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Fuel ion densities and distributions in fusion plasmas: Modeling and analysis for neutron emission spectrometry2012Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Neutrons produced in fusion reactions in a magnetically confined plasma carry information about the distributions and densities of the fuel ions in the plasma. This thesis presents work where various theoretical models of different fuel ion distributions in the plasma are used to calculate modeled components of the neutron energy spectrum. The calculated components can then be compared with measured data, either to benchmark and validate the model or to derive various plasma parameters from the experimental data. Neutron spectra measured with the spectrometers TOFOR and the MPR, which are both installed at the JET tokamak in England, are used for this purpose. The thesis is based on three papers.

    The first paper presents the analysis of TOFOR data from plasmas heated with neutral beams and radio frequency waves tuned to the third harmonic of the deuterium cyclotron frequency, which creates fast (supra thermal) ions in the MeV range. It is found that effects of the finite Larmor radii of the fast ions need to be included in the modeling in order to understand the data. These effects are important for fast ion measurements if there is a gradient in the fast ion distribution function with a scale length that is comparable to - or smaller than - the width of the field of view of the measuring instrument, and if this scale length is comparable to - or smaller than - the Larmor radii of the fast ions.

    The second paper presents calculations of the neutron energy spectrum from the T(t,n)4He reaction, for JET relevant fuel ion distributions. This is to to form a starting point for the investigation of the possibility to obtain fast ion information from the t-t neutron spectrum, in a possible future deuterium-tritium campaign at JET. The t-t spectrum is more challenging to analyze than the d-d and d-t cases, since this reaction has three (rather than two) particles in the final state, which results in a broad continuum of neutron energies rather than a peak. However, the presence of various final state interactions - in particular between the neutron and the 4He - might still allow for spectrometry analysis.

    Finally, in Paper III, a method to derive the fuel ion ratio, nt/nd, is presented and applied to MPR data from the JET d-t campaign in 1997. The trend in the results are consistent with Penning trap measurements of the fuel ion ratio at the plasma edge, but the absolute numbers are not the same. Measuring the fuel ion ratio in the core plasma is an important task for fusion research, and also a very complicated one. Future work should aim at measuring this quantity in several independent ways, which should then be cross checked against each other.

  • 222.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Neutron Emission Spectrometry for Fusion Reactor Diagnosis: Method Development and Data Analysis2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    It is possible to obtain information about various properties of the fuel ions deuterium (D) and tritium (T) in a fusion plasma by measuring the neutron emission from the plasma. Neutrons are produced in fusion reactions between the fuel ions, which means that the intensity and energy spectrum of the emitted neutrons are related to the densities and velocity distributions of these ions.

    This thesis describes different methods for analyzing data from fusion neutron measurements. The main focus is on neutron spectrometry measurements, using data used collected at the tokamak fusion reactor JET in England. Several neutron spectrometers are installed at JET, including the time-of-flight spectrometer TOFOR and the magnetic proton recoil (MPRu) spectrometer.

    Part of the work is concerned with the calculation of neutron spectra from given fuel ion distributions. Most fusion reactions of interest – such as the D + T and D + D reactions – have two particles in the final state, but there are also examples where three particles are produced, e.g. in the T + T reaction. Both two- and three-body reactions are considered in this thesis. A method for including the finite Larmor radii of the fuel ions in the spectrum calculation is also developed. This effect was seen to significantly affect the shape of the measured TOFOR spectrum for a plasma scenario utilizing ion cyclotron resonance heating (ICRH) in combination with neutral beam injection (NBI).

    Using the capability to calculate neutron spectra, it is possible to set up different parametric models of the neutron emission for various plasma scenarios. In this thesis, such models are used to estimate the fuel ion density in NBI heated plasmas and the fast D distribution in plasmas with ICRH.

  • 223.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Lerche, E.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Van Eester, D.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Neutron spectrometry measurements of energetic deuterons in ICRF heated plasmas with the ITER-like wall at JET2014Ingår i: 41th EPS Conference on Plasma Physics 2014 (EPS 2014): Europhysics Conference Abstracts, 2014Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    At JET, experiments have been conducted in order to optimize the performance of ion cyclotron radio-frequency (ICRF) heating in the presence of the newly installed ITER-like wall. The ICRF was tuned to the cyclotron frequency of minority hydrogen (H), which is also the 2nd harmonic of the cyclotron frequency of deuterium (D). The relative H concentration was varied from a few percent up to about 25 percent in a series of plasma discharges and the neutron time-of-flight spectrometer TOFOR was used to measure the energy spectrum of neutrons from the D(D,n)3He reaction during these discharges. It could be seen that the signal from ICRF accelerated deuterons depended strongly on H concentration. This observation indicates that the ICRF power absorbed by D at the 2nd harmonic cyclotron resonance increases with decreasing H concentration. This is in qualitative agreement with theoretical expectations obtained from the plasma wave equation solver TOMCAT.

  • 224.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Castegnetti, Giuseppe
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Luca, Giacomelli
    Department of Physics, Università degli Studi di Milano-Bicocca, Milano, Italy.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Deuterium density profile determination at JET using a neutron camera and a neutronspectrometer2014Ingår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 85, nr 11, s. 11E106-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

  • 225.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Calculating fusion neutron energy spectra from arbitrary reactant distributions2016Ingår i: Computer Physics Communications, ISSN 0010-4655, E-ISSN 1879-2944, Vol. 199, s. 40-46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Directional Relativistic Spectrum Simulator (DRESS) code can perform Monte-Carlo calculations of reaction product spectra from arbitrary reactant distributions, using fully relativistic kinematics. The code is set up to calculate energy spectra from neutrons and alpha particles produced in the D(d, n)3He and T(d, n)4He fusion reactions, but any two-body reaction can be simulated by including the corresponding cross section. The code has been thoroughly tested. The kinematics calculations have been benchmarked against the kinematics module of the ROOT Data Analysis Framework. Calculated neutron energy spectra have been validated against tabulated fusion reactivities and against an exact analytical expression for the thermonuclear fusion neutron spectrum, with good agreement. The DRESS code will be used as the core of a detailed synthetic diagnostic framework for neutron measurements at the JET and MAST tokamaks.

  • 226.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gatu Johnson, M
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Pinches, S D
    Sharapov, S E
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    JET EFDA contributors, .
    Finite Larmor radii effects in fast ion measurements with neutron emission spectrometry2013Ingår i: Plasma Physics and Controlled Fusion, ISSN 0741-3335, E-ISSN 1361-6587, Vol. 55, nr 1, s. 015008-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    When analysing data from fast ion measurements it is normally assumed that the gyro-phase distribution of the ions is isotropic within the field of view of the measuring instrument. This assumption is not valid if the Larmor radii of the fast ions are comparable to—or larger than—the gradient scale length in the spatial distribution of the ions, and if this scale length is comparable to—or smaller than—the width of the field of view of the measuring instrument. In this paper the effect of such an anisotropy is demonstrated by analysing neutron emission spectrometry data from a JET experiment with deuterium neutral beams together with radiofrequency heating at the third harmonic of the deuterium cyclotron frequency. In the experiment, the neutron time-of-flight spectrometer TOFOR was used to measure the neutrons from the d(d,n) 3 He-reaction. Comparison of the experimental data with Monte Carlo calculations shows that the finite Larmor radii of the fast ions need to be included in the modelling to get a good description of the data. Similar effects are likely to be important for other fast ion diagnostics, such as γ -ray spectroscopy and neutral particle analysis, as well.

  • 227.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gatu Johnson, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Pinches, S.D.
    Sangaroon, Siriyaporn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sharapov, S.E.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Klimek, Iwona
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Finite Larmor radii effects in fast ion measurements as demonstrated using neutron emission spectrometry of JET plasmas heated with 3rd harmonic ICRF2011Ingår i: 38th EPS Conference on Plasma Physics 2011 (EPS 2011): Europhysics Conference Abstracts, 2011Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper demonstrates how the finite Larmor radii (FLR) of fast ions can affect fast ion measurements by studying data from the neutron time-of-flight spectrometer TOFOR. Neutron spectra were calculated from a model of the fast ion velocity distribution for a JET experiment with 3rd harmonic ICRF heating of deuterium beams. It was found that  FLR effects need to be considered to get a good description of the data,  if the Larmor radius of the fast ions are comparable to the width of the field of view of the instrument. This applies not only to results from neutron spectrometry but also to other types of fast ion diagnostics.

  • 228.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Giacomelli, L.
    CNR, Ist Fis Plasma, Milan, Italy.
    Gorini, G.
    CNR, Ist Fis Plasma, Milan, Italy;Univ Milano Bicocca, Dipartimento Fis G Occhialini, Milan, Italy.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Kiptily, V. G.
    Culham Sci Ctr, CCFE, Abingdon, Oxon, England.
    Mantsinen, M.
    BSC, Barcelona, Spain;ICREA, Pg Llus Companys 23, E-08010 Barcelona, Spain.
    Nocente, M.
    CNR, Ist Fis Plasma, Milan, Italy;Univ Milano Bicocca, Dipartimento Fis G Occhialini, Milan, Italy.
    Sahlberg, Arne
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Salewski, M.
    Tech Univ Denmark, Dept Phys, Lyngby, Denmark.
    Sharapov, S.
    Culham Sci Ctr, CCFE, Abingdon, Oxon, England.
    Tardocchi, M.
    CNR, Ist Fis Plasma, Milan, Italy.
    Measuring fast ions in fusion plasmas with neutron diagnostics at JET2019Ingår i: Plasma Physics and Controlled Fusion, ISSN 0741-3335, E-ISSN 1361-6587, Vol. 61, nr 1, artikel-id 014027Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fast ions in fusion plasmas often leave characteristic signatures in the neutron emission from the plasma. In this paper, we show how neutron measurements can be used to study fast ions and give examples of physics results obtained on present day tokamaks. The focus is on measurements with dedicated neutron spectrometers and with compact neutron detectors used in each channel of neutron profile monitors. A measured neutron spectrum can be analyzed in several different ways, depending on the physics scenario under consideration. Gross features of a fast ion energy distribution can be studied by applying suitably chosen thresholds to the measured spectrum, thus probing ions with different energies. With this technique it is possible to study the interaction between fast ions and MHD activity, such as toroidal Alfven eigenmodes (TAEs) and sawtooth instabilities. Quantitative comparisons with modeling can be performed by a direct computation of the neutron emission expected from a given fast ion distribution. Within this framework it is also possible to determine physics parameters, such as the supra-thermal fraction of the neutron emission, by fitting model parameters to the data. A detailed, model-independent estimate of the fast ion distribution can be obtained by analyzing the data in terms of velocity space weight functions. Using this method, fast ion distributions can be resolved in both energy and pitch by combining neutron and gamma-ray measurements obtained along several different sightlines. Fast ion measurements of the type described in this paper will also be possible at ITER, provided that the spectrometers have the dynamic range required to resolve the fast ion spectral features in the presence of the dominating thermonuclear neutron emission. A dedicated high-resolution neutron spectrometer has been designed for this purpose.

  • 229.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Neutron emission from a tritium rich fusion plasma: simulations in view of a possible future d-t campaign at JET2012Ingår i: 39th EPS Conference on Plasma Physics 2012 (EPS 2012): Europhysics Conference Abstracts, 2012Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

     Neutron energy spectra from the t(t,2n)4He (t-t) reaction has been calculated for different fuel ion distributions, in order to assess the possibility to use this reaction when analyzing neutron spectrometry data from plasmas with very high tritium fraction. The shape of the neutron spectrum is determined by three-body kinematics, and is modified by interactions between the reaction products, primarily between the neutron and the 4He. The results indicate that the analysis of a t-t spectrum will be more challenging than for the d-t and d-d reactions. However, for fast ions in the MeV range, produced e.g. by harmonic radiofrequency heating and neutral beam injection, it should still be possible to obtain fast ion information from the neutron spectrum.

  • 230.
    Eriksson, Jacob
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Nocente, Massimo
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Cazzaniga, Carlo
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ericsson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gorini, Giuseppe
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sharapov, Sergei
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Tardocchi, Marco
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dual sightline measurements of MeV range deuterons with neutron and gamma-ray spectroscopy at JET2015Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 55, nr 12, artikel-id 123026Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Observations made in a JET experiment aimed at accelerating deuterons to the MeV range by third harmonic radio-frequency (RF) heating coupled into a deuterium beam are reported. Measurements are based on a set of advanced neutron and gamma-ray spectrometers that, for the first time, observe the plasma simultaneously along vertical and oblique lines of sight. Parameters of the fast ion energy distribution, such as the high energy cut-off of the deuteron distribution function and the RF coupling constant, are determined from data within a uniform analysis framework for neutron and gamma-ray spectroscopy based on a one-dimensional model and by a consistency check among the individual measurement techniques. A systematic difference is seen between the two lines of sight and is interpreted to originate from the sensitivity of the oblique detectors to the pitch-angle structure of the distribution around the resonance, which is not correctly portrayed within the adopted one dimensional model. A framework to calculate neutron and gamma-ray emission from a spatially resolved, two-dimensional deuteron distribution specified by energy/pitch is thus developed and used for a first comparison with predictions from ab initio models of RF heating at multiple harmonics.

    The results presented in this paper are of relevance for the development of advanced diagnostic techniques for MeV range ions in high performance fusion plasmas, with applications to the experimental validation of RF heating codes and, more generally, to studies of the energy distribution of ions in the MeV range in high performance deuterium and deuterium-tritium plasmas.

  • 231.
    Eriksson, Moa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Förutsättningarna för ett parallellt generation IV system vid svensk nybyggnation av kärnkraft.2013Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    A new build in the Swedish nuclear power system would entail increased re-quirements for the proposed repository, which is adapted after the reactors of today. With a fast reactor, capable of burning nuclear waste, operating in parallel with the light water reactors, the increased requirements on the repository could be reduced.

    In this thesis, simulations of a light water reactor and a fast reactor have been performed by using the Monte Carlo code Serpent to investigate the changes in the fuel inventory. The light water reactor in the study is a boiling water reactor and the fast reactor of the type sodium-cooled fast reactor and they have been used for three different operation scenarios.

    By studying the fuel composition and the results from the simulations of the three scenarios conclusions can be drawn. Conclusions regarding the change of the fuel inventory and decay heat in Clab as well as the interim storage facility and in the repository. Depending on the operation alternative the changes dif-fered significantly and especially regarding the mass of burned actinides for different fuels in the fast reactor.

    The lowest increase of fuel assemblies was meet when using 50 years old fuel with 20MWd/kg U burnout and 2,0 % enrichment for start up of the fast reactor and 30 years old fuel assemblies with 50MWd/kg U burnout and 4,7 % enrichment for the further operation of the reactor.

    The increase of the number of fuel assemblies was 3174, which is equivalent to 641tons of heavy metal. Further this means an increase of the decay heat with 1,2MW.

    To decide whether or not it is possible to run a sodium-cooled fast reactor paral-lel with a light water reactor to compensate for the produced decay heat and fuel assemblies, further investigations concerning the deposit in the repository needs to be done.

  • 232.
    Eriksson, Olof
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Victor
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Metod för framställning av layouter till Forsmarks Kraftgrupp AB:s övervakningssystem2015Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This project has taken place at Forsmark nuclear power plant. To keep the powerplant safe, Forsmark utilizes two separate safety systems for monitoring alarms, firedetectors and video surveillance in all of the plant. In these systems, blueprints areused as background images to help locate where an alarm goes off. To generate theseimages, the blueprints need to be converted from their original file type into commonimage files. The process of doing this has up until now faltered and as a result thelayouts produced have had some major issues. Therefore, this project is carried outto develop a new standardized way of doing this, resulting in a manual to be used asguidance for making future layouts.

    After examining how it used to be done, we started from scratch and developed anew way of completing the task. The process now consisted of two parts: part onewhere preparations of the blueprints were being made and a second part where theconversion to an image was being finalized. Completing the layouts is easier and fasterthan before, and the image quality is much better. As it turned out, the two systemswere too different to use the same layout, thus leaving us making separate layouts forthe two. This is not a major issue, since the systems have separate administratorswho produce their own layouts.

    The manual is a step-by-step guide which thoroughly describes the process, withimages supporting the text.

  • 233. Fan, G. W.
    et al.
    Fukuda, M.
    Nishimura, D.
    Cai, X. L.
    Fukuda, S.
    Hachiuma, I.
    Ichikawa, C.
    Izumikawa, T.
    Kanazawa, M.
    Kitagawa, A.
    Kuboki, T.
    Lantz, Mattias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Mihara, M.
    Nagashima, M.
    Namihira, K.
    Ohkuma, Y.
    Ohtsubo, T.
    Ren, Zhongzhou
    Sato, S.
    Sheng, Z. Q.
    Sugiyama, M.
    Suzuki, S.
    Suzuki, T.
    Takechi, M.
    Yamaguchi, T.
    Xu, W.
    Density distribution of 8Li and 8B$ and capture reaction at low energy2015Ingår i: Phys. Rev. C, Vol. 91, artikel-id 014614Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reaction cross sections of 8Li on stable targets were measured at intermediate energies. With the existing experimental data of interaction cross sections at 790 MeV/nucleon the nucleon density distribution of 8Liwas extracted by the use of the modified Glauber model. Meanwhile, the existing data of 8B have been also reanalyzed. Structures of 8Li and 8B were compared through the density. On the basis of dilute surface densities, the discussion of 7Li(n,γ)8Li and 7Be(p,γ)8B capture reactions was performed within the framework of the direct capture reaction mechanism. The calculations agreed quite well with the experimental data as well as other analyses.

  • 234.
    Favalli, Andrea
    et al.
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    Vo, Duc
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    Grogan, B.
    Oak Ridge National Laboratory, Oak Ridge, TN, USA.
    Jansson, Peter
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Liljenfeldt, Henrik
    Oak Ridge National Laboratory, Oak Ridge, TN, USA.
    Mozin, Vladimir
    Lawrence Livermore National Laboratory, Livermore, CA, USA.
    Schwalbach, Peter
    European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg.
    Sjöland, Anders
    Swedish Nuclear Fuel and Waste Management Company.
    Tobin, S.J.
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    Trellue, Holly
    Los Alamos National Laboratory, Los Alamos, NM, USA.
    Vaccaro, Stefano
    European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg.
    Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden2016Ingår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 820, s. 102-111Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of the Next Generation Safeguards Initiative (NGSI)–Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI–SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute 137Cs count rate and the 154Eu/137Cs, 134Cs/137Cs, 106Ru/137Cs, and 144Ce/137Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity’s behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  • 235.
    Fluch, Ulrike
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Paneta, Valentina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Primetzhofer, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Ott, Sascha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Uniform distribution of post-synthetic linker exchange in metal-organic frameworks revealed by Rutherford backscattering spectrometry2017Ingår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 53, nr 48, s. 6516-6519Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rutherford backscattering spectrometry (RBS) has been used for the first time to study post-synthetic linker exchange (PSE) in metal-organic frameworks. RBS is a non-invasive method to quantify the amount of introduced linker, as well as providing a means for depth profiling in order to identify the preferred localization of the introduced linker. The exchange of benzenedicarboxylate (bdc) by similarly sized 2-iodobenzenedicarboxylate (I-bdc) proceeds considerably slower than migration of I-dbc through the UiO-66 crystal. Consequently, the I-bdc is found evenly distributed throughout the UiO-66 samples, even at very short PSE exposure times.

  • 236.
    Franzén, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Evaluation of Fuel Assembly Bow Penalty Peaking Factors for Ringhals 3: Based on a Cycle Specific Core Water Gap Distribution2017Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In recent years, fuel assembly bow in Ringhals 3 has started to increase again after lower levels of bow. Normally, the fuel assemblies are straight axially. One of the consequences of fuel assembly bow is perturbed power distribution across the core, resulting in smaller margins of safety during operation. A way of ensuring safe operation is add-on margins, penalties, dependent on bow amplitude, added to the power peaking factors. A new method of producing these penalties, based on realistic water gap distribution derived from measurements, was used.

    By comparing the new penalties with the currently used penalties, the currently used penalties were concluded to be around 10 percent smaller for both FdH, the radial power peaking factor penalty, and FQ, the local power peaking factor penalty. The currently used penalties hence are significantly lower.

    However, the conclusion should be seen as an indication, rather than directly implementable, since there is potential to evolve the method further and eliminate sources of error.

  • 237.
    Frazer, D.
    et al.
    Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA..
    Qvist, Staffan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA..
    Parker, S.
    Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA..
    Krumwiede, D. L.
    Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA..
    Caro, M.
    Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM USA..
    Tesmer, J.
    Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM USA..
    Maloy, S. A.
    Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM USA..
    Wang, Y. Q.
    Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM USA..
    Hosemann, P.
    Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA..
    Degradation of HT9 under simultaneous ion beam irradiation and liquid metal corrosion2016Ingår i: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 479, s. 382-389Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A potentially promising coolant/structural material pair for a liquid-metal-cooled fast reactors is lead bismuth eutectic (LBE) coolant with the ferritic/martensitic steel HT9. The challenge of deploying LBE, however, is the corrosive environment it creates for structural materials. This corrosion can be mitigated with precise oxygen content control in the LBE to allow for the growth of passive protective oxide layers on the surface of the steel. In this paper, results are reported from the Irradiation Corrosion Experiment II (ICE-II), which allowed the simultaneous irradiation of a sample while in contact with LBE. It was found that a characteristic multilayer structure with an outer Fe3O4 oxide and inner FeCr2O4 spinel was grown and the oxidation was significantly larger in the irradiated region when compared to the region that was only exposed to LBE corrosion. Possible mechanisms are discussed to help understand this irradiation enhanced corrosion behavior.

  • 238.
    Fritz, Malin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Control rod drop during hot zero power: RIA in BWR2013Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    During operation of nuclear power reactors reactivity initiated accidents (RIA) can occur, such as a control rod drop. If this occurs, the reactivity increase dramatically and leads to an increase in power, fuel enthalpy and fuel temperature. The fuel and reactor can be damaged. A methodology to simulate these accidents has been developed for Forsmark Nuclear Power Plant in cooperation with Westinghouse, referred to as the POLCA7 methodology. The POLCA7 methodology results in a limit for fuel failure regarding reactivity of the control rod that dropped in pcm/control rod percent. The limit is estimated from simulations in POLCA7, a static and deterministic code and POLCA-T, a dynamic code. The aim of this thesis is to evaluate the methodology and investigate what happens in a reactor if a control rod drops during hot zero power. Hot zero power is a phase during start-up, where the power is low (~2% of installed power) and the reactor have operation pressure and temperature.

    The POLCA7 methodology was applied on historic cycles in Forsmark. To evaluate the POLCA7 methodology the control rod drop was simulated in S3K, a dynamic software. The results from these cycles indicate that the limit for fuel failure set in the POLCA7 methodology in pcm/control rod percent is very conservative for fuel with low and medium burnup. Even though the limit is exceeded, the dynamic simulation in S3K shows that the fuel is far from failure regarding SSM limits in fuel enthalpy and cladding temperature. In this thesis new limits in POLCA7 has been generated, which is remarkably higher than the original limit from the POLCA7 methodology.

    To challenge the methodology, an unrealistic fuel design was simulated with fuel with high burnup surrounded by high reactive fuel. With this fuel design, the enthalpy limit from SSM was exceeded for the fuel with high burnup. The limit from the POLCA7 methodology was exceeded which indicate that the POLCA7 methodology meets the goal of detecting severe RIAs. Fuel with high burnup seems to be the most important fuel to investigate at a RIA simulation.

    Another discovery is that POLCA7 gives the most severe accident at 2% power, but in S3K it is given by 3-4% power. This is a problem with the POLCA7 methodology.

    Suggestions are made on how to lower the calculation time and improve the methodology. A control rod sequence that gives an even power distribution and a core with the fuel with high burnup in the periphery and only a few fresh fuels is preferred to avoid damage at a RIA. A control rod sequence was designed for the new cycle in Forsmark 1, in order to try to create a cycle without problems due to RIA. The new sequence was a success with no control rods exceeding the limit of 82 pcm/control rod percent, and it shows that conclusions about the impact of the sequence are correct.

    Conclusion is made that the methodology should be further investigated and there are good chances to develop a good and time efficient analysis in the future. One presented suggestion is to have a dynamic simulation of the incident instead of the axial simulation. The evaluation with SSM’s limits would then be direct.

  • 239.
    Fritzell, Anni
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    System aspects on safeguards for the back-end of the Swedish nuclear fuel cycle2008Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 240.
    Fritzell, Anni
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    van der Meer, Klaas
    Diversion path analysis for the Swedish geological repository2008Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The Swedish strategy to handle the spent fuel from the nuclear power plants isthe direct disposal in a geological repository. The safeguards regime covering allnuclear material in the state will be expanded to cover the new repository, whichwill require a novel safeguards approach due mainly to the inaccessibility of thefuel after disposal. The safeguards approach must be able to provide a high levelof assurance that the fuel in the repository not diverted, but must also be resourceefficient. An attractive approach with regards to use of resources is to monitoronly the access points to the repository, i.e. the openings. The implementationof such an approach can only be allowed if it is shown to be sufficiently secure.With the purpose of determining the applicability of this “black box” approach, adiversion path analysis for the Swedish geological repository has been carried out.The result from the analysis shows that all credible diversion paths could be cov-ered by the black-box safeguards approach provided that the identified boundaryconditions can be met.

  • 241. Fukuda, M.
    et al.
    Takechi, M.
    Nishimura, D.
    Mihara, M.
    Matsumiya, R.
    Matsuta, K.
    Minamisono, T.
    Ohtsubo, T.
    Ohkuma, Y.
    Shimbara, Y.
    Suzuki, S.
    Watanabe, R.
    Izumikawa, T.
    Momota, S.
    Suzuki, T.
    Yamaguchi, T.
    Kuboki, T.
    Hachiuma, I.
    Namihira, K.
    Nakajima, S.
    Kobayashi, K.
    Sumikama, T.
    Miyashita, Y.
    Yoshinaga, K.
    Tanaka, K.
    Aoi, N.
    Fukuda, N.
    Inabe, N.
    Kameda, D.
    Kubo, T.
    Kusaka, K.
    Lantz, Mattias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. RIKEN Nishina Center.
    Ohnishi, T.
    Ohtake, M.
    Suda, T.
    Takeda, H.
    Yanagisawa, Y.
    Yoshida, A.
    Yoshida, K.
    Ozawa, A.
    Moriguchi, T.
    Ohishi, H.
    Itoh, Y.
    Ishibashi, Y.
    Ogawa, K.
    Yasuda, Y.
    Geissel, H.
    Winkler, M.
    Sato, S.
    Kanazawa, M.
    Kitagawa, A.
    Reaction cross section studies at NIRS and RIBF2010Ingår i: American Institute of Physics Conference Series, American Institute of Physics, 2010, Vol. 1238, s. 270-273Konferensbidrag (Refereegranskat)
    Abstract [en]

    Reaction cross sections for stable nuclei at intermediate energies have been measured precisely and systematically. The data have been found to be reproduced nicely by the optical‐limit approximation of Glauber theory modified to include the nucleon multiple scattering effect and the Fermi‐motion effect. Applying this prescription, the nucleon density distribution of 17Ne has been studied. The surface structure of 8B and 11Be has been also studied using this prescription and hydrogen targets. Using the RIBF that has just started application to studies of exotic nuclei, neutron‐rich Ne isotopes around the Island of Inversion have been investigated through measurements of their interaction cross sections.

  • 242.
    Gabro, Dany
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Virtual Studies of Nuclear Fission: A comparison of n- and p- induced fission using GEF2017Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    A General Description of Fission Observables (GEF) version 2016/1.2 is a software which simulates various types of fission. The main objective of this project is to compare the proton induced fission with the neutron induced fission of the same fissioning system. The proton induced fission was recently introduced to GEF and is relatively untested. Furthermore another task is to study the energy dependence in the same compound nucleus. The project will focus on simulating and comparing 238U(p,f) with 238Np(n,f) and 239Np*(f) as well as 232Th(p,f) with 232Pa(n,f) and 233Pa*(f ). The simulations were also compared to experimental data acquired by the division of applied nuclear physics at Uppsala University. The results show that the p-induced channel behaves very similar to the Compound Nucleus (CN) channel in contrary with the (n,f) channel. However when comparing the simulated data to the experimental data, there seems to be clear differences.

  • 243.
    Gallart, D.
    et al.
    BSC, Barcelona, Spain.
    Mantsinen, M. J.
    BSC, Barcelona, Spain;ICREA, Barcelona, Spain.
    Challis, C.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Frigione, D.
    CRE Frascati, Assoc EURATOM ENEA, Frascati, Italy.
    Graves, J.
    Ecole Polytech Fed Lausanne, Ctr Rech Phys Plasmas, CH-1015 Lausanne, Switzerland.
    Belonohy, E.
    Max Planck Inst Plasma Phys, Garching, Germany.
    Casson, F.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Czarnecka, A.
    Assoc EURATOM IPPLM, Inst Plasma Phys & Laser Microfus, Warsaw, Poland.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Garcia, J.
    CEA, Ctr Etud Nucl Cadarache, Cadarache, France.
    Goniche, M.
    CEA, Ctr Etud Nucl Cadarache, Cadarache, France.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hobirk, J.
    Max Planck Inst Plasma Phys, Garching, Germany.
    Jaquet, P.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Joffrin, E.
    CEA, Ctr Etud Nucl Cadarache, Cadarache, France.
    Krawczyk, N.
    Assoc EURATOM IPPLM, Inst Plasma Phys & Laser Microfus, Warsaw, Poland.
    King, D.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Lennholm, M.
    European Comiss, B-1049 Brussels, Belgium.
    Lerche, E.
    ERM KMS, LPP, Brussels, Belgium.
    Pawelec, E.
    Opole Univ, Inst Phys, Ul Oleska 48, PL-45052 Opole, Poland.
    Saez, X.
    BSC, Barcelona, Spain.
    Sertoli, M.
    Max Planck Inst Plasma Phys, Garching, Germany.
    Sips, G.
    Max Planck Inst Plasma Phys, Garching, Germany.
    Solano, E.
    CIEMAT, Assoc EURATOM CIEMAT Fus, Madrid, Spain.
    Tsalas, M.
    EURATOM, FOM Inst DIFFER, POB 120, Nieuwegein, Netherlands.
    Vallejos, P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Valisa, M.
    Assoc Euratom ENEA Fus, Consorzio RFX, I-35137 Padua, Italy.
    Modelling of JET hybrid plasmas with emphasis on performance of combined ICRF and NBI heating2018Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 58, nr 10, artikel-id 106037Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the 2015-2016 JET campaigns, many efforts have been devoted to the exploration of high-performance plasma scenarios envisaged for DT operation in JET. In this paper, we review various key recent hybrid discharges and model the combined ICRF+NBI heating. These deuterium discharges with deuterium beams had the ICRF antenna frequency tuned to match the cyclotron frequency of minority H at the centre of the tokamak coinciding with the second harmonic cyclotron resonance of D. The modelling takes into account the synergy between ICRF and NBI heating through the second harmonic cyclotron resonance of D beam ions, allowing us to assess its impact on the neutron rate R-NT. For discharges carried out with a fixed ICRF antenna frequency and changing toroidal magnetic field to vary the resonance position, we evaluate the influence of the resonance position on the heating performance and central impurity control. The H concentration is varied between discharges in order to test its role in the heating performance. It is found that discharges with a resonance beyond similar to 0.15 m from the magnetic axis R-0 suffer from MHD activity and impurity accumulation in these plasma conditions. According to our modelling, the ICRF enhancement of R-NT increases with the ICRF power absorbed by deuterons as the H concentration decreases. We find that in the recent hybrid discharges, this ICRF enhancement varies due to a variation of H concentration and is in the range of 10%-25%. The modelling of a recent record high-performance hybrid discharge shows that ICRF fusion yield enhancement of similar to 30% and similar to 15% respectively can be achieved in the ramp-up phase and during the main heating phase. We extrapolate the results to DT and find that the best performing hybrid discharges correspond to an equivalent fusion power of similar to 7.0 MW in DT. Finally, an optimization analysis of the bulk ion heating for the DT scenario reveals around 15%-20% larger bulk ion heating for the He-3 minority scenario as compared to the H minority scenario.

  • 244.
    Garzotti, L.
    et al.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Challis, C.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Dumont, R.
    CEA, IRFM, F-13108 St Paul Les Durance, France.
    Frigione, D.
    ENEA CR Frascati, Unita Tecn Fus, Via E Fermi 45, I-00044 Rome, Italy.
    Graves, J.
    Ecole Polytech Fed Lausanne, Swiss Plasma Ctr, CH-1015 Lausanne, Switzerland.
    Lerche, E.
    Ecole Royale Mil Renaissancelaan, Lab Plasma Phys, Koninklijke Mil Sch, 30 Ave Renaissance, B-1000 Brussels, Belgium.
    Mailloux, J.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Mantsinen, M.
    Barcelona Supercomp Ctr, Barcelona, Spain;ICREA, Pg Lluis Co 23, Barcelona 08010, Spain.
    Rimini, F.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Casson, F.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Czarnecka, A.
    Inst Plasma Phys & Laser Microfus, Hery 23, PL-01497 Warsaw, Poland.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Felton, R.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Frassinetti, L.
    KTH, EES, Fus Plasma Phys, SE-10044 Stockholm, Sweden.
    Gallart, D.
    Barcelona Supercomp Ctr, Barcelona, Spain.
    Garcia, J.
    CEA, IRFM, F-13108 St Paul Les Durance, France.
    Giroud, C.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Joffrin, E.
    CEA, IRFM, F-13108 St Paul Les Durance, France.
    Kim, Hyun-Tae
    Culham Sci Ctr, EUROfus Programme Management Unit, Culham OX14 3DB, England.
    Krawczyk, N.
    Inst Plasma Phys & Laser Microfus, Hery 23, PL-01497 Warsaw, Poland.
    Lennholm, M.
    Culham Sci Ctr, EUROfus Programme Management Unit, Culham OX14 3DB, England.
    Lomas, P.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Lowry, C.
    Culham Sci Ctr, EUROfus Programme Management Unit, Culham OX14 3DB, England.
    Meneses, L.
    Univ Lisbon, Inst Plasmas & Fusao Nucl, Inst Super Tecn, Lisbon, Portugal.
    Nunes, I
    Univ Lisbon, Inst Plasmas & Fusao Nucl, Inst Super Tecn, Lisbon, Portugal.
    Roach, C. M.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Romanelli, M.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Sharapov, S.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Silburn, S.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Sips, A.
    Culham Sci Ctr, EUROfus Programme Management Unit, Culham OX14 3DB, England.
    Stefániková, E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi.
    Tsalas, M.
    FOM Inst DIFFER, Eindhoven, Netherlands.
    Valcarcel, D.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Valovic, M.
    Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.
    Scenario development for D-T operation at JET2019Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 59, nr 7, artikel-id 076037Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The JET exploitation plan foresees D-T operations in 2020 (DTE2). With respect to the first D-T campaign in 1997 (DTE1), when JET was equipped with a carbon wall, the experiments will be conducted in presence of a beryllium-tungsten ITER-like wall and will benefit from an extended and improved set of diagnostics and higher additional heating power (32 MW neutral beam injection + 8 MW ion cyclotron resonance heating). There are several challenges presented by operations with the new wall: a general deterioration of the pedestal confinement; the risk of heavy impurity accumulation in the core, which, if not controlled, can cause the radiative collapse of the discharge; the requirement to protect the divertor from excessive heat loads, which may damage it permanently. Therefore, an intense activity of scenario development has been undertaken at JET during the last three years to overcome these difficulties and prepare the plasmas needed to demonstrate stationary high fusion performance and clear alpha particle effects. The paper describes the status and main achievements of this scenario development activity, both from an operational and plasma physics point of view.

  • 245. Gassner, T.
    et al.
    Schoepf, K.
    Sharapov, S. E.
    Kiptily, V. G.
    Pinches, S. D.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Deuterium beam acceleration with 3rd harmonic ion cyclotron resonance heating in Joint European Torus: Sawtooth stabilization and Alfven eigenmodes2012Ingår i: Physics of Plasmas, ISSN 1070-664X, E-ISSN 1089-7674, Vol. 19, nr 3, s. 032115-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Experiments on accelerating NBI-produced deuterium (D) beam ions from their injection energy of similar to 110 keV up to the MeV energy range with 3rd harmonic ion cyclotron resonance heating were performed on the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)]. A renewed set of nuclear diagnostics was used for analysing fast D ions during sawtooth stabilization, monster sawtooth crashes, and during excitation of Alfven eigenmodes (AEs) residing inside the q = 1 radius. The measurements and modeling of the fast ions with the nonlinear HAGIS code [S. D. Pinches et al., Comput. Phys. Commun. 111, 133 (1998)] show that monster sawtooth crashes are strongly facilitated by the AE-induced re-distribution of the fast D ions from inside the q = 1 radius to the plasma edge. [http://dx.doi.org/10.1063/1.3696858]

  • 246. Gavagnin, Marco
    et al.
    Wanzenboeck, Heinz D
    Belic, Domagoj
    Shawrav, Mostafa M
    Persson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gunnarsson, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Svedlindh, Peter
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Bertagnolli, Emmerich
    Magnetic force microscopy study of shape engineered FEBID iron nanostructures2014Ingår i: Physica Status Solidi (a) applications and materials science, ISSN 1862-6300, E-ISSN 1862-6319, Vol. 211, nr 2, s. 368-374Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The capability to control matter down to the nanoscale level in combination with the novel magnetic properties of nanomaterials have attracted increasing attention in the last few decades due to their applications in magnetic sensing, hard disc data storage and logic devices. Therefore, many efforts have been devoted to the implementation of both nanofabrication methods as well as characterization of magnetic nanoelements. In this study, Fe-based nanostructures have been synthesized on Si(100) by focused electron beam induced deposition (FEBID) utilizing iron pentacarbonyl as precursor. The so obtained nanostructures exhibit a remarkably high iron content (Fe>80at.%), expected to give rise to a ferromagnetic behaviour. For that reason, magnetic force microscopy (MFM) analyses were performed on the obtained FEBID Fe nanostructures. Moreover, object oriented micromagnetic framework (OOMMF) magnetic simulations have been executed to study the influence of the geometry on the magnetic properties of iron single-domain nanowires. FEBID is a mask-less nanofabrication method based on the injection of precursor gas molecules in proximity of the deposition area where their decomposition is locally induced by a focused electron beam.

  • 247. Gavagnin, Marco
    et al.
    Wanzenboeck, Heinz D.
    Wachter, Stefan
    Shawrav, Mostafa M.
    Persson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gunnarsson, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Svedlindh, Peter
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Stoeger-Pollach, Michael
    Bertagnolli, Emmerich
    Free-Standing Magnetic Nanopillars for 3D Nanomagnet Logic2014Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 6, nr 22, s. 20254-20260Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nanomagnet logic (NML) is a relatively new computation technology that uses arrays of shape-controlled nanomagnets to enable digital processing. Currently, conventional resist-based lithographic processes limit the design of NML circuitry to planar nanostructures with homogeneous thicknesses. Here, we demonstrate the focused electron beam induced deposition of Fe-based nanomaterial for magnetic in-plane nanowires and out-of-plane nanopillars. Three-dimensional (3D) NML was achieved based on the magnetic coupling between nanowires and nanopillars in a 3D array. Additionally, the same Fe-based nanomaterial was used to produce tilt-corrected high-aspect-ratio probes for the accurate magnetic force microscopy (MFM) analysis of the fabricated 3D NML gate arrays. The interpretation of the MFM measurements was supported by magnetic simulations using the Object Oriented MicroMagnetic Framework. Introducing vertical out-of-plane nanopillars not only increases the packing density of 3D NML but also introduces an extra magnetic degree of freedom, offering a new approach to input/output and processing functionalities in nanomagnetic computing.

  • 248. Gherendi, M.
    et al.
    Zoita, V. L.
    Craciunescu, T.
    Johnson, M. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi.
    Pantea, A.
    Baltog, I.
    Edlington, T.
    Hellesen, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Kiptily, V.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Murari, A.
    Popovichev, S.
    Neutron field parameter measurements on the JET tokamak by means of super-heated fluid detectors2012Ingår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 83, nr 10, s. 10E124-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The neutron field parameters (fluence and energy distribution) at a specific location outside the JET Torus Hall have been measured by means of super-heated fluid detectors (or bubble detectors) in combination with an independent, time-of-flight, technique. The bubble detector assemblies were placed at the end of a vertical line of sight at about 16 m from the tokamak mid plane. Spatial distributions of the neutron fluence along the radial and toroidal directions have been obtained using two-dimensional arrays of bubble detectors. Using a set of three bubble detector spectrometers the neutron energy distribution was determined over a broad energy range, from about 10 keV to above 10 MeV, with an energy resolution of about 30% at 2.5 MeV. The very broad energy response allowed for the identification of energy features far from the main fusion component (around 2.45 MeV for deuterium discharges).

  • 249.
    Giacomelli, L.
    et al.
    CNR, Ist Fis Plasma P Caldirola, Milan, Italy.
    Belli, F.
    ENEA CR Frascati, Dipartimento FSN, Rome, Italy.
    Binda, Federico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Milocco, A.
    Univ Milano Bicocca, Dipartimento Fis G Occhialini, Milan, Italy;Culham Sci Ctr, CCFE, Abingdon, Oxon, England.
    Popovicev, S.
    Culham Sci Ctr, CCFE, Abingdon, Oxon, England.
    Syme, D. B.
    Culham Sci Ctr, CCFE, Abingdon, Oxon, England.
    Neutron emission spectroscopy of D plasmas at JET with a compact liquid scintillating neutron spectrometer2018Ingår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 89, nr 10, artikel-id 10I113Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Neutron emission spectroscopy is a diagnostic technique that allows for energy measurements of neutrons born in nuclear reactions. The JET tokamak fusion experiment (Culham, UK) has a special role in this respect as advanced spectrometers for 2.5 MeV and 14 MeV neutrons have been developed here for the first time for measurements of the neutron emission spectrum from D and DT plasmas with unprecedented accuracy. Twin liquid scintillating neutron spectrometers were built and calibrated at the Physikalisch-Technische Bundesanstalt (PTB) (Braunschweig, Germany) and installed on JET in the recent years with tangential-equatorial (KM12) and vertical-radial (KM13) view lines, with the latter only recently operational. This article reports on the performance of KM12 and on the development of the data analysis methods in order to extract physics information upon D ions kinematics in JET auxiliary-heated D plasmas from 2.5 MeV neutron measurements. The comparison of these results with the correspondents from other JET neutron spectrometers is also presented: their agreement allows for JET unique capability of multi-lines of sight neutron spectroscopy and for benchmarking other 14 MeV neutron spectrometers installed on the same lines of sight in preparation for the DT experimental campaign at JET.

  • 250. Giacomelli, L.
    et al.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Gorini, G.
    Horton, L.
    Murari, A.
    Popovichev, S.
    Syme, D. B.
    Tomographic analysis of neutron and gamma pulse shape distributions from liquid scintillation detectors at Joint European Torus2014Ingår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 85, nr 2, s. 023505-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Joint European Torus (JET, Culham, UK) is the largest tokamak in the world devoted to nuclear fusion experiments of magnetic confined Deuterium (D)/Deuterium-Tritium (DT) plasmas. Neutrons produced in these plasmas are measured using various types of neutron detectors and spectrometers. Two of these instruments on JET make use of organic liquid scintillator detectors. The neutron emission profile monitor implements 19 liquid scintillation counters to detect the 2.45 MeV neutron emission from D plasmas. A new compact neutron spectrometer is operational at JET since 2010 to measure the neutron energy spectra from both D and DT plasmas. Liquid scintillation detectors are sensitive to both neutron and gamma radiation but give light responses of different decay time such that pulse shape discrimination techniques can be applied to identify the neutron contribution of interest from the data. The most common technique consists of integrating the radiation pulse shapes within different ranges of their rising and/or trailing edges. In this article, a step forward in this type of analysis is presented. The method applies a tomographic analysis of the 3-dimensional neutron and gamma pulse shape and pulse height distribution data obtained from liquid scintillation detectors such that n/gamma discrimination can be improved to lower energies and additional information can be gained on neutron contributions to the gamma events and vice versa.

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