uu.seUppsala University Publications
Change search
Refine search result
1 - 28 of 28
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Håkansson, A
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Nuclear and Particle Physics. Department of Neutron Research. Department of Physics and Astronomy, Nuclear Physics.
    Bäcklin, A
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Nuclear and Particle Physics. Department of Neutron Research. Department of Physics and Astronomy, Nuclear Physics.
    Jacobsson Svärd, S
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Nuclear and Particle Physics. Department of Neutron Research. Department of Physics and Astronomy, Nuclear Physics.
    Jansson, P
    Hildingsson, L
    Strålningsmönster avslöjar manipulerat bränsle1998In: Nucleus, ISSN 1104-4578, no 3Article in journal (Other (popular scientific, debate etc.))
  • 2.
    Håkansson, A
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Nuclear and Particle Physics. Department of Neutron Research. Department of Physics and Astronomy, Nuclear Physics.
    Jacobsson Svärd, S
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Nuclear and Particle Physics. Department of Neutron Research. Department of Physics and Astronomy, Nuclear Physics.
    Bäcklin, A
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Nuclear and Particle Physics. Department of Neutron Research. Department of Physics and Astronomy, Nuclear Physics.
    Vad gammastrålning kan berätta om kärnbränsle2003In: KOSMOS , Årsbok för Svenska FysikersamfundetArticle in journal (Other (popular scientific, debate etc.))
  • 3.
    Håkansson, Ane
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Andersson, Camilla
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Jacobsson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Tomography as a means for Experimental Verification of the Integrity of Irradiated Nuclear Fuel1997Conference paper (Refereed)
  • 4.
    Håkansson, Ane
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jacobsson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    An experimental study of the neutron emission from spent PWR fuel1997Report (Other academic)
    Abstract [en]

    Measurements of the thermal and epithermal neutron emission from eleven 15x15 and fourteen 17x17 PWR fuel assemblies have been performed. In the measurements a FORK detector supplied by Euroatom was utilised. The neutron flux was observed to depend on the burnup to approximately the fourth power. Also the strong dependence on initial enrichment could be verified. The latter dependency suggests a possible method to determine the initial enrichment. Such a method is considered as an important feature of safeguard as well as in fuel processing at the planned encapsulation plant for spent nuclear fuel.

  • 5.
    Jacobsson, S
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Backlin, A
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Hakansson, A
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    A tomographic method for experimental verification of the integrity of spent nuclear fuel2000In: Applied Radiation and Isotopes, ISSN 0969-8043, E-ISSN 1872-9800, Vol. 53, no 4-5, p. 681-689Article in journal (Refereed)
    Abstract [en]

    A tomographic method for verification of the integrity of spent nuclear fuel assemblies has been developed. The gamma radiation field emanating from emitted radiation from within the assembly is recorded and utilised for reconstructing the internal source

  • 6.
    Jacobsson, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics.
    Andersson, Camilla
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics.
    A Tomographic Method for Experimental Verification of the Integrity of Spent Nuclear Fuel1999In: 4th Topical Meeting on Industrial Radiation and Radioisotope Measurement Applications, IRRMA'99: October 3-7, 1999, Velvet Cloak Inn, Raleigh, North Carolina, USA, American Nuclear Society, 1999Conference paper (Refereed)
  • 7.
    Jacobsson, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Andersson, Camilla
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    A Tomographic Method for Verification of the Integrity of Spent Nuclear Fuel1998Report (Other academic)
    Abstract [en]

    A tomographic method for experimental investigation of the integrity of usedLWR fuel has been developed. It is based on measurements of the gamma radiation fromthe fission products in the fuel rods. A reconstruction code of the algebraic type has beenwritten. The potential of the technique has been examined in extensive simulationsassuming a gamma-ray energy of either 0.66 MeV (137Cs) or 1.27 MeV (154Eu).The resultsof the simulations for BWR fuel indicate that single fuel rods or groups of rods replacedwith water or fresh fuel can be reliably detected independent of their position in the fuelassembly using 137Cs radiation. For PWR fuel the same result is obtained with the exceptionof the most central positions. Here the more penetrable radiation from 154Eu must be used inorder to allow a water channel to be distinguished from a fuel rod.

    The results of the simulations have been verified experimentally for a 8x8 BWRfuel assembly. Special equipment has been constructed and installed at the interim storageCLAB. The equipment allows the mapping of the radiation field around a fuel assemblywith the aid of a germanium detector fitted with a collimator with a vertical slit. Theintensities measured in 2 520 detector positions were used as input for the reconstructioncode used in the simulations. The results agreed very well with the simulations and revealedsignificantly a position containing a water channel in the central part of the assembly.

  • 8.
    Jacobsson, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Andersson, Camilla
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    A Tomographic Method for Verification of the Integrity of Spent Nuclear Fuel1998Report (Other academic)
  • 9.
    Jacobsson, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    A Tomographic Method for Verification of the Integrity of Spent Nuclear Fuel Assemblies - II: Experimental Investigation2001In: Nuclear Technology, ISSN 0029-5450, E-ISSN 1943-7471, Vol. 135, no 2, p. 146-153Article in journal (Refereed)
    Abstract [en]

    A tomographic method for verification of the integrity of used light water reactor fuel has been experimentally investigated. The method utilizes emitted gamma rays from fission products in the fuel rods. The radiation field is recorded in a large number of positions relative to the assembly, whereby the source distribution is reconstructed using a special-purpose reconstruction code.

    An 8 × 8 boiling water reactor fuel assembly has been measured at the Swedish interim storage (CLAB), using installed gamma-scanning equipment modified for the purpose of tomography. The equipment allows the mapping of the radiation field around a fuel assembly with the aid of a germanium detector fitted with a collimator with a vertical slit. Two gamma-ray energies were recorded: 662 keV (137Cs) and 1274 keV (154Eu). The intensities measured in 2520 detector positions were used as input for the tomographic reconstruction code. The results agreed very well with simulations and significantly revealed a position containing a water channel in the central part of the assembly.

  • 10.
    Jacobsson, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Tomographic measurements of thermal power in nuclear fuel rods: Stage 2 progress report December 19991999Report (Other academic)
    Abstract [en]

    This report presents recent progress in a project on tomographic measurements of thermal power in nuclear fuel rods, carried out at Uppsala University and funded via the Swedish Centre for Nuclear Technology, KTC. The project is executed in three stages, of which this report describes a set of studies made during the second stage.

    Experimental studies have been performed using a laboratory mock-up, modelling a fuel assembly of the BWR8x8 type, in which tomographic data collection is made using BGO scintillator detectors and a data-acquisition system based on single-channel analysers. Gamma-ray scattering has been identified as a major contributor to systematic errors in the measurement of relative activity contents in the 63 rods of the mock-up assembly. Since scattering causes build-up of radiation at lower energies, it may be taken into account in the tomographic analyses by introducing a so-called effective attenuation coefficient in the reconstruction models, being slightly lower than the theoretical coefficient. Studies show that this approach may enhance the precision in the measurement of relative rod-activity contents from about 3‑4% down to about 1.2‑1.4%.

    Data collection has also been performed using a separate, spectroscopic data-acquisition system, in a set of measurements where inactive rods have been used to introduce scattering in order to analyse its effects on the collected data. The results indicate that most of the adverse effects of scattering may be eliminated by deploying a spectroscopic system with peak analysis including background subtraction. Consequently, such a system should be considered for Stage 3 of this project.

    Simulation studies have also been executed to analyse the measurement uncertainties introduced by geometric deviations from the nominal positions of the four sections of a SVEA‑64 fuel assembly. It was found that the standard deviation of relative rod activities caused by the largest displacements allowed by the nominal gaps enclosing each section was about 0.5%, which may be considered acceptable.

  • 11.
    Jacobsson Svärd, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Osifo, Otasowie
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Willman, Christofer
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Jansson, Peter
    Non-destructive experimental determination of the pin-power distribution in nuclear fuel2003Conference paper (Other academic)
    Abstract [en]

    A need for validation of modern core-analysis codes with respect to the calculated pin-power distribution has been recognized. A non-destructive experimental method for such validation has been developed, based on a tomographic technique. Each axial node of the fuel assembly is measured separately and the relative pin-by-pin content of the direct fission product Ba-140 is determined. Investigations performed so far indicate that 1-2% (1 σ) accuracy can be obtained.

    A measuring device has been constructed which, when fully equipped, is designed to measure a complete BWR assembly in 25 axial nodes within an eight-hour work shift. The applicability of the constructed device has been demonstrated in measurements at the Swedish BWR Forsmark 2 on irradiated fuel with a cooling time of 4-5 weeks. Data from the core-analysis code POLCA-7 have been compared to measured pin-by-pin contents of Ba-140. An agreement of 3.1% (1 σ) has been demonstrated.

    As compared to the conventional method, involving gamma scanning of individual fuel pins, this method does not require the fuel to be disassembled. Neither does the fuel channel have to be removed. The cost per measured fuel pin is in the order of 20 times lower than the conventional method.

  • 12.
    Jacobsson Svärd, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics. Kärnfysik.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics. Kärnfysik.
    Osifo, Otasowie
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Willman, Christofer
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Kärnfysik.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics. Kärnfysik.
    Nondestructive Experimental Determination of the Pin-Power Distribution in Nuclear Fuel Assemblies2005In: Nuclear Technology, ISSN 0029-5450, Vol. 151, no 1, p. 70-76Article in journal (Refereed)
    Abstract [en]

    A need for validation of modern production codes with respect to the calculated pin-power distribution has been recognized. A nondestructive experimental method for such validation has been developed based on a tomographic technique. The gamma-ray flux distribution is recorded in each axial node of the fuel assembly separately, whereby the relative rod-by-rod content of the fission product 140Ba is determined. Measurements indicate that 1 to 2% accuracy (1 sigma) is achievable.

    A device has been constructed for in-pool measurements at reactor sites. The applicability has been demonstrated in measurements at the Swedish boiling water reactor (BWR) Forsmark 2 on irradiated fuel with a cooling time of 4 to 5 weeks. Data from the production code POLCA-7 have been compared to measured rod-by-rod contents of 140Ba. An agreement of 3.1% (1 sigma) has been demonstrated.

    It is estimated that measurements can be performed on a complete BWR assembly in 25 axial nodes within an 8-h work shift. As compared to the conventional method, involving gamma scanning of individual fuel rods, this method does not require the fuel to be disassembled nor does the fuel channel have to be removed. The cost per measured fuel rod is estimated to be an order of magnitude lower than the conventional method.

  • 13.
    Jacobsson Svärd, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Uppsala University.
    Detection of Dislocated Individual Fuel Rods in a Nuclear Fuel Assembly using Tomographic Measurements1998Report (Other academic)
    Abstract [en]

    A method is suggested for identifying and quantifying possible dislocations of individual fuel rods in an irradiated nuclear fuel assembly. The method is designed for application in tomographic measurements of nuclear fuel assemblies. The source distribution of gamma radiation is reconstructed using a tomographic algorithm, in which the pixel pattern is adapted to the assembly geometry. By comparing the reconstructed source concentration in opposite parts of each fuel rod in the assembly, quantitative information may be obtained about possible dislocations.

    Theoretical considerations have been applied and data from simulations of a nuclear fuel assembly with single dislocated rods have been used in tomographic reconstructions. The investigations indicate that the method should be applicable for identification of dislocations larger than a few tenths of a mm.

  • 14.
    Jacobsson Svärd, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Uppsala University.
    Tomografisk bestämning av termisk effekt i kärnbränslestavar - Förstudie1996Report (Other academic)
    Abstract [sv]

    Denna rapport redovisar en förstudie av möjligheterna att med tomografisk mätning bestämma effektfördelningen i ett bränsleelement. Förstudien avses vara en första fas i en serie av tre, som, om utfallet successivt bedöms tillräckligt lovande, skall leda till en utprovad prototyp för tomografisk effektmätning.

  • 15. Jansson, P
    et al.
    Håkansson, A
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Neutron Research. Department of Nuclear and Particle Physics. Department of Physics and Astronomy, Nuclear Physics.
    Bäcklin, A
    Department of Nuclear and Particle Physics. Department of Physics and Astronomy, Nuclear Physics.
    Detection of Partial Defects in Irradiated BWR Fuel Assemblies. A Preliminary Study2002In: INMM 43rd Annual Meeting (INMM),Orlando, Florida, USA, June 23-27, 2002, 2002Conference paper (Refereed)
  • 16.
    Jansson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Kärnfysik.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Kärnfysik.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Kärnfysik.
    Calculations of the Neutron Flux Outside BWR 8×8 Spent-Fuel Assemblies and the Sensitivity to Fuel Pin Diversion2004In: Nuclear Technology, ISSN 0029-5450, E-ISSN 1943-7471, Vol. 146, no 1, p. 58-64Article in journal (Refereed)
    Abstract [en]

    The possibility of detecting replaced fuel rods in a spent-fuel assembly by means of measurement of the emitted neutron- and gamma-ray radiation has been investigated by computer simulations. The radiation field outside a boiling water reactor 8 × 8 fuel assembly with varying patterns of fuel rods replaced with lead dummies was calculated using a simple model for the source distribution and the Monte Carlo code MCNP-4C for the radiation field. In particular, the sensitivity of the thermal neutron field as measured in a Fork detector to various replacement patterns was investigated. The results suggest a detection limit of 5% of the fuel mass replaced, i.e., 3 out of 63 rods, independently of the pattern of the replaced rods.

  • 17.
    Jansson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Gamma-ray measurements of spent PWR fuel and determination of residual power1997Report (Other academic)
    Abstract [en]

    The method for determining residual thermal power in spent BWR fuel described in ISV-4/97 have been used in an extended study where spent PWR fuel assemblies have been considered. The experimental work has been carried out at the interim storage CLAB. By using the 137Cs radiation it is shown in the present study that it is possible to experimentally determine the residual thermal power within 3%.

  • 18.
    Jansson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jacobsson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Gamma-Ray Spectroscopy Measurements of Decay Heat in Spent Nuclear Fuel2002In: Nuclear Science and Engineering, ISSN 0029-5639, Vol. 141, no 2, p. 129-139Article in journal (Refereed)
    Abstract [en]

    A method for determining the residual thermal power in spent nuclear fuel using gamma-ray spectroscopy is suggested. It is based on the correlation between the residual power and the 137Cs activity, which is nearly linear for fuel with cooling times between 10 and 50 yr. Using available data of calorimetrically measured values of the decay heat in 69 boiling water reactor and pressurized water reactor spent-fuel assemblies resulted in agreement with a standard deviation of 3%.

  • 19.
    Jansson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jacobsson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    A Method of Measuring Decay Heat in Spent Nuclear Fuel using Gamma-ray Spectroscopy2001In: Waste Management Symposium 2001 (WM'01), 2001Conference paper (Refereed)
    Abstract [en]

    In this paper, a method is presented for determining the decay heat in spent nuclear fuel by using gamma-ray spectroscopy. Using this method, the decay heat may be determined within ten minutes per assembly i.e. it is well suited for industrial applications in, for example, an encapsulation facility. The method has been tested and evaluated in the wet Swedish Central Storage for Spent Fuel, CLAB. Although only tested in a wet storage, the method should also be applicable for dry storage.

    The objective of developing the method was primarily to investigate possibilities to achieve a fast, robust and reasonable accurate determination of decay heat by gamma-ray measurements on fuel assemblies. Such a method could also be for verification of burnup and cooling time, for safeguard purposes prior to encapsulation, (1).

    So far, measurements and calculations on 35 BWR- and 34 PWR-assemblies, with various nuclear data, have been performed. The test measurements, using preliminary measuring equipment, have shown that the decay heat may be determined within an uncertainty of 3%.

  • 20.
    Jansson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jacobsson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Håkansson, A
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Tomographic measurement of thermal power in nuclear fuel: Stage 1 - Final report1998Report (Other academic)
    Abstract [en]

    This report summarises the results obtained in the first stage of a three-stage project on “Tomographic measurement of thermal power in nuclear fuel”, carried out at Uppsala University and funded via the Swedish Centre for Nuclear Technology, KTC. The goal of the three-stage project is to build a tomographic device and use it for non-destructive measurement of the pin-wise thermal power in nuclear fuel assemblies at a Swedish nuclear power plant.

    Covered in the report are descriptions of the algorithms and software for tomographic reconstruction developed for the purpose, results of sensitivity studies for geometric uncertainties, tests of detector systems in a laboratory environment as well as on nuclear fuel at a reactor site, descriptions of a laboratory mock-up intended to be used in the second step of the project and estimations of the achievable uncertainty in measured relative pin-wise power using the suggested methods.

  • 21.
    Jansson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jacobsson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    A Feasibility Study of BGO Scintillation Detectors for Tomographic Measurements on Nuclear Fuel2000Report (Other academic)
    Abstract [en]

    A study of BGO detectors has been performed. The purpose of the study was to determine geometrical shape of the scintillator crystals in order to be suited for use in tomographic measurements on nuclear fuel. Computer calculations using Monte Carlo techniques were used. High count-rate experiments were performed on three nuclear fuel assemblies with the shapes of the crystals determined by the calculations. The resulting characteristics of the detectors show that they are suitable in a tomographic measurement.

  • 22.
    Jansson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jacobsson Svärd, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    A Device for Nondestructive Experimental Determination of the Power Distribution in a Nuclear Fuel Assembly2006In: Nuclear science and engineering, ISSN 0029-5639, E-ISSN 1943-748X, Vol. 152, no 1, p. 76-86Article in journal (Refereed)
    Abstract [en]

    There is a general interest in experimentally determining the power distribution in nuclear fuel. The prevalent method is to measure the distribution of the fission product 140Ba, which represents the power distribution over the last few weeks. In order to obtain the rod-by-rod power distribution, the fuel assemblies have to be dismantled.

    In this paper, a device for experimental nondestructive determination of the thermal rod-by-rod power distribution in boiling water reactor and pressurized water reactor fuel assemblies is described. It is based on measurements of the 1.6-MeV gamma radiation from the decay of 140Ba/La and utilizes a tomographic method to reconstruct the rod-by-rod source distribution. No dismantling of the fuel assembly is required.

    The device is designed to measure an axial node in 20 min with a precision of >2% (1). It is primarily planned to be used for validation of production codes for core simulation but may also be used for safeguards purposes.

  • 23. Matsson, Ingvar
    et al.
    Grapengiesser, Björn
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Kärnfysik.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Kärnfysik.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences. Kärnfysik.
    Fission Gas Release Determination Using an Anti-Compton Shield Detector1998In: Nuclear Technology, ISSN 0029-5450, Vol. 122, no 3, p. 276-283Article in journal (Refereed)
    Abstract [en]

    Poolside measurements of fission gas release (FGR) in fuel pins have been made using gamma-ray spectroscopy with a Ge detector, measuring 85Kr activity in the fuel rod plenum. The gamma-ray energy spectra from irradiated nuclear fuel are characterized by prominent Compton distributions that can obscure the weak 514-keV 85Kr peak. To improve the sensitivity, the detector has been provided with an anti-Compton shield of six Bi3Ge4O12 detectors. Laboratory tests of the detector system showed that the maximum peak-to-Compton (p/c) ratio was improved by a factor of ~6. The results of the poolside measurement p/c ratio showed a somewhat smaller improvement (a factor of ~4) because of scattered gamma radiation from the surrounding material. However, the precision in the poolside FGR measurements was improved substantially utilizing the Compton shield.

  • 24.
    Osifo, Otasowie
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Neutron Research, Applied Nuclear Physics.
    Jacobsson Svärd, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Willman, Christofer
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Lundqvist, Tobias
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Verification and determination of the decay heat in spent PWR fuel by means of gamma scanning2008In: Nuclear science and engineering, ISSN 0029-5639, E-ISSN 1943-748X, Vol. 160, no 1, p. 129-143Article in journal (Refereed)
    Abstract [en]

    Decay heat is an important design parameter at the future Swedish spent nuclear fuel repository. It will be calculated for each fuel assembly using dedicated depletion codes, based on the operator-declared irradiation history. However, experimental verification of the calculated decay heat is also anticipated. Such verification may, be obtained by, gamma scanning using the established correlation between the decay heat and the emitted gamma-ray intensity from Cs-137. In this procedure, the correctness of the operator-declared fuel parameters can be verified. Recent achievements of the gamma-scanning technique include the development of a dedicated spectroscopic data-acquisition system and the use of an advanced calorimeter for calibration. Using this system, the operator-declared burnup and cooling time of 31 pressurized water reactor fuel assemblies was verified experimentally, to within 2.2% (1 sigma) and 1.9% (1 sigma), respectively. The measured decay heat agreed with calorimetric data within 2.3% (1 sigma). whereby the calculated decay, heat was verified within 2.3% (1 sigma). The measuring time per fuel assembly was similar to 15 min. In case reliable operator-declared data are not available, the gamma-scanning technique also provides a means to independently measure the decay, heat. The results obtained in this procedure agreed with calorimetric data within 2.7% (1 sigma).

  • 25.
    Tarvainen, Matti
    et al.
    Finnish Centre for Radiation and Nuclear Safety.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Calibration of the TVO spent BWR reference fuel assembly: Final report on the joint Task JNT61 of the Finnish and Swedish Support Propgrammes to IAEA Safeguards1992Report (Other academic)
  • 26.
    Vogt, Jan
    et al.
    Swedish Nuclear Fuel and Waste Management Co, SKB.
    Agrenius, Lennart
    Agrenius Ingenjorsbyra AB.
    Jansson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Jacobsson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Radiation Sciences.
    Measurements of Decay Heat and Gamma-ray Intensity of Spent LWR Fuel Assemblies1998In: IAEA International Symposium on Storage of Spent Fuel from Power Reactors, Vienna, Austria, November 1998, 1998Conference paper (Refereed)
  • 27.
    Willman, Christofer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Osifo, Otasowie
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jacobsson Svärd, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    A nondestructive method for discriminating MOX fuel from LEU fuel for safeguards purposes2006In: Annals of Nuclear Energy, ISSN 0306-4549, E-ISSN 1873-2100, Vol. 33, no 9, p. 766-773Article in journal (Refereed)
    Abstract [en]

    Plutonium-rich mixed oxide fuel (MOX) is increasingly used in thermal reactors. However, spent MOX fuel could be a potential source of nuclear weapons material and a safeguards issue is therefore to determine whether a spent nuclear fuel assembly is of MOX type or of LEU (Low Enriched Uranium) type.

    In this paper, we present theoretical and experimental results of a study that aims to investigate the possibilities of using gamma-ray spectroscopy to determine whether a nuclear fuel assembly is of MOX or of LEU type.

    Simulations with the computer code ORIGEN-ARP have been performed where LEU and MOX fuel types with varying enrichment and burnup as well as different irradiation histories have been modelled. The simulations indicate that the fuel type determination may be achieved by using the intensity ratio Cs-134/Eu-154.

    An experimental study of MOX fuel of 14 x 14 PWR type and LEU fuel of both 15 x 15 and 17 x 17 type is also reported in this paper. The outcome of the experimental study support the conclusion that MOX fuel may be discriminated from LEU fuel by measuring the suggested isotopic ratio.

  • 28.
    Willman, Christofer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics.
    Håkansson, Ane
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Neutron Research. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Osifo, Otasowie
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Neutron Research. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics.
    Bäcklin, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Jacobsson Svärd, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Neutron Research. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Nuclear and Particle Physics, Nuclear Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Nondestructive assay of spent nuclear fuel with gamma-ray spectroscopy2006In: Annals of Nuclear Energy, ISSN 0306-4549, Vol. 33, no 5, p. 427-438Article in journal (Refereed)
    Abstract [en]

    An important issue in nuclear safeguards is to verify operator-declared data of spent nuclear fuel. Various techniques have therefore been assigned for this purpose. A nondestructive approach is to measure the gamma radiation from spent nuclear fuel assemblies. Using this technique, parameters such as burnup and cooling time can be calculated or verified.

    In this paper, we propose the utilization of gamma rays from 137Cs, 134Cs and 154Eu to determine the consistency of operator-declared information. Specifically, we have investigated to what extent irradiation histories can be verified.

    Computer simulations were used in order to determine limits for detecting small deviations from declared data. In addition, the technique has been experimentally demonstrated on 12 PWR fuel assemblies.

    A technique for determining burnup and cooling time for fuel assemblies where no operator-declared information is available is also presented. In such a case, the burnup could be determined with 1.6% relative standard deviation and the cooling time with 1.5%.

1 - 28 of 28
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf