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• 51.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
LOCA Transient Tests at HRP2016Övrigt (Övrig (populärvetenskap, debatt, mm))
• 52.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Notes on the world energy supply2017Övrigt (Övrig (populärvetenskap, debatt, mm))
• 53.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Optimization of Equipment for Tomographic Measurements of Void Distributions using Fast Neutrons2011Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)

This licentiate thesis describes a novel nondestructive measuring technique for determiningspatial distributions of two-phase water flows. In Boiling Water Reactors, which compose themajority of the world's commercial nuclear reactors, this so called void distribution is of importance for safe operation.

The presented measurement technique relies on fast neutron transmission tomography using portable neutron generators. Varying hardware options for such an instrument based on this technique and a prototype instrument, which is under construction, are described. The main design parameters are detailed and motivated from a performance point of view. A Paretomultiple objective optimization of the count rate and image unsharpness is presented. The resulting instrument design comprises an array of plastic scintillators for neutron detection. Such detector elements allow for spectroscopic data acquisition and subsequent reduction of background events at low energy by means of introducing an energy threshold in the analysis.

The thesis includes two papers: In paper I, the recoil proton energy deposition distribution resulting from the interaction of the incoming neutrons is investigated for thin plastic scintillator elements. It is shown that the recoil proton losses have a large effect on the pulse height distribution and the intrinsic neutron detection efficiency is calculated for varying energy thresholds.

In paper II the performance of the planned FANTOM device is investigated using the particle transport code MCNP5. An axially symmetric phantom void distribution is modeled and there construction is compared with the correct solution. According to the solutions, the phantom model can be reconstructed with 10 equal size ring-shaped picture elements, with a precision of better than 5 void percent units using a deuterium-tritium neutron generator with a yield of 3 · 107 neutrons per second and a measurement time of 13 h. However, it should be noted that commercial neutron generators with a factor of 103 higher yields exist and that the measurement time could decrease to less than a minute if such a neutron generator would beutilized.

• 54.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Validation of axial flux profiles and development of a modified axial flux model using gamma scans of IFA-6772019Rapport (Övrigt vetenskapligt)
• 55.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Neutron Tomography Using Mobile Neutron Generators for Assessment of Void Distributions in Thermal Hydraulic Test Loops2015Konferensbidrag (Refereegranskat)

Detailed knowledge of the lateral distribution of steam (void) and water in a nuclear fuel assembly is of great value for nuclear reactor operators and fuel manufacturers, with consequences for both reactor safety and economy of operation. Therefore, nuclear relevant two-phase flows are being studied at dedicated thermal-hydraulic test loop, using twophase flow systems ranging from simplified geometries such as heated circular pipes to full scale mock-ups of nuclear fuel assemblies. Neutron tomography (NT) has been suggested for assessment of the lateral distribution of steam and water in such test loops, motivated by a good ability of neutrons to penetrate the metallic structures of metal pipes and nuclear fuel rod mock-ups, as compared to e. g. conventional X-rays, while the liquid water simultaneously gives comparatively good contrast. However, these stationary test loops require the measurement setup to be mobile, which is often not the case for NT setups. Here, it is acknowledged that fast neutrons of 14 MeV from mobile neutron generators constitute a viable option for a mobile NT system. We present details of the development of neutron tomography for this purpose at the division of Applied Nuclear Physics at Uppsala University. Our concept contains a portable neutron generator, exploiting the fusion reaction of deuterium and tritium, and a detector with plastic scintillator elements designed to achieve adequate spatial and energy resolution, all mounted in a light-weight frame without collimators or bulky moderation to allow for a mobile instrument that can be moved about the stationary thermal hydraulic test sections. The detector system stores event-to-event pulse-height information to allow for discrimination based on the energy deposition in the scintillator elements. Experimental results from the tomographic assessment of axially symmetric test objects are shown, as well as simulation results from a scaled up version of the instrument for nonsymmetrical objects in quarter fuel-bundle size objects. In conclusion, the application of tomography on inch-wide vertical pipes has been experimentally demonstrated and simulation results indicate that tomography of the void distribution in nonsymmetrical vertical flows in quarter BWR fuel bundles is also feasible.

• 56.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
OECD Halden Reactor Project, Inst Energy Technol, Box 173, NO-1751 Halden, Norway.
A computerized method (UPPREC) for quantitative analysis of irradiated nuclear fuel assemblies with gamma emission tomography at the Halden reactor2017Ingår i: Annals of Nuclear Energy, ISSN 0306-4549, E-ISSN 1873-2100, Vol. 110, s. 88-97Artikel i tidskrift (Refereegranskat)

The Halden reactor project (HRP) has recently developed a gamma emission tomography instrument dedicated for measurements of irradiated nuclear fuel in collaboration with Westinghouse and Uppsala University. This instrument is now assembled and the first experimental measurements have been performed on fuel assemblies irradiated in the Halden reactor. The objective of the instrument is to map the distribution of radioisotopes of interest in the fuel, e.g. 137Cs or 140La/Ba, and for this purpose, a spectroscopic high-purity Germanium detector has been selected, which enables the identification and tomographic reconstruction of separate isotopes by their characteristic gamma rays.

To gain from the analysis of the data from this new instrument, and in the future from other gamma emission tomography instruments for nuclear fuels, various reconstruction methods are available that vary in the accuracy and the amount of detail obtainable in the analysis. This paper presents the details of the working principles of a new code for gamma emission tomography, the UPPREC (UPPsala university REConstruction) code. It is a development in MATLABTM code with the aim to produce detailed quantitative images of the investigated fuel.

In this paper, the methods assembled for the analysis of data collected by this novel instrument are described and demonstrated and a benchmark is presented using single rod gamma scanning. It is shown that the UPPREC methodology improves the accuracy of the reconstructions by removing the errors introduced by the presence of highly attenuating fuel and structural material in the fuel assembly. With the introduction of UPPREC, detailed quantitative cross-sectional images of nuclide concentrations in nuclear fuel are now able to be obtained by nondestructive means. This has potential applications in both nuclear fuel diagnostics and in safeguards.

• 57.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
OECD Halden Reactor Project.
Feasibility Study of Using Gamma Emission Tomography for Identification of Leaking Fuel Rods in Commercial Fuel Assemblies2017Konferensbidrag (Refereegranskat)
• 58.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
OECD Halden Reactor Project. OECD Halden Reactor Project.
Inspection of a LOCA Test Rod at the Halden Reactor Project using Gamma Emission Tomography2016Ingår i: Top Fuel 2016 - LWR Fuels with Enhanced Safety and Performance, American Nuclear Society, 2016Konferensbidrag (Refereegranskat)

The LOCA test series IFA-650 conducted at the OECD Halden Reactor Project (HRP) has provided unique data on the performance of fuel rods during LOCA transients. One focus of the current investigations is the performance of the fuel in the ballooning stage of the LOCA transient. In this stage, relocation of fuel material is a possibility, in which case pellet fragments fall down to fill the void introduced by the increased volume of the ballooned cladding. This increases the heat load in that region, further promoting corrosion of the cladding. A special concern in the case of high-burnup fuels is the increasing number of small fuel fragments, which may be expected to cause a higher packing fraction in the ballooned region.

In this work, a novel technique is presented for assessing the average density of the fuel material in the ballooned region of LOCA test rods. The investigation is based on non-destructive gamma emission tomography measurements, using the dedicated instrument recently developed at the HRP in collaboration with Westinghouse (Sweden) and Uppsala University. In this approach, the gamma radiation field surrounding the test rod has been measured with a narrowly collimated HPGe detector. Tomographic reconstruction of the data was performed, providing the radial gamma-ray source distribution within the measured volume, which reveals the fuel fragment distribution. From this, the density of the fuel in the measured volume (i.e., the packing fraction) may be calculated.

The technique has been used to investigate a LOCA test rod of the Halden Reactor Project LOCA series. The LOCA experiment was carried out about one month prior to the gamma tomography examination. The results show that the distribution of the relocated fuel can be imaged using gamma rays from fission products. The reconstructions of the 662 keV rays from 137Cs and 1596 keV from 140Ba/La are demonstrated. In addition, the peaks of activation products offer valuable information on the location of the test rig structures, which may be utilized in a quantitative tomographic reconstruction to assess the spatially resolved packing fraction.

• 59.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Halden Reactor Project. Halden Reactor Project.
Inspection of LOCA Test Rod IFA-650.15 Using Gamma Emission Tomography2016Rapport (Övrigt vetenskapligt)
• 60.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
OECD Halden Reactor Project. Halden Reactor Project.
Inspection of LOCA Test Rod IFA-650.16 Using Gamma Emission Tomography2018Rapport (Övrigt vetenskapligt)
• 61.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
OECD Halden Reactor Project. Halden Reactor Project.
Inspection of LOCA Test Rod IFA-650.16 Using Gamma Emission Tomography2019Konferensbidrag (Övrigt vetenskapligt)
• 62.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
OECD Halden Reactor Project. Halden Reactor Project.
Quantitative Gamma Emission Tomography Inspection of LOCA rod IFA-650.152017Ingår i: EHPG, 2017Konferensbidrag (Refereegranskat)
• 63.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Neutron tomography of axially symmetric objects using 14 MeV neutrons from a portable neutron generator2014Ingår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 85, nr 8, s. 085109-Artikel i tidskrift (Refereegranskat)

In nuclear boiling water reactor cores, the distribution of water and steam (void) is essential for both safety and efficiency reasons. In order to enhance predictive capabilities, void distribution assessment is performed in two-phase test-loops under reactor-relevant conditions. This article proposes the novel technique of fast-neutron tomography using a portable deuterium-tritium neutron generator to determine the void distribution in these loops.Fast neutrons have the advantage of high transmission through the metallic structures and pipes typically concealing a thermal-hydraulic test loop, while still being fairly sensitive to the water/void content. However, commercially available fast-neutron generators also have the disadvantage of a relatively low yield and fast-neutron detection also suffers from relatively low detection efficiency. Fortunately, some loops are axially symmetric, a property which can be exploited to reduce the amount of data needed for tomographic measurement, thus limiting the interrogation time needed.In this article, three axially-symmetric test objects depicting a thermal-hydraulic test loop have been examined; steel pipes with outer diameter 24 mm, thickness 1.5 mm and with three different distributions of the plastic material POM inside the pipes. Data recorded with the FANTOM fast-neutron tomography instrument have been used to perform tomographic reconstructions to assess their radial material distribution. Here, a dedicated tomographic algorithm that exploits the symmetry of these objects has been applied, which is described in the paper.Results are demonstrated in 20 rixel (radial pixel) reconstructions of the interior constitution and 2D visualization of the pipe interior is demonstrated. The local POM attenuation coefficients in the rixels were measured with errors (RMS) of 0.025, 0.020 and 0.022 cm-1, solid POM attenuation coefficient. The accuracy and precision is high enough to provide a useful indication on the flow mode, and a visualization of the radial material distribution can be obtained. A benefit of this system is its potential to be mounted at any axial height of a two-phase test section without requirements for pre-fabricated entrances or windows. This could mean a significant increase in flexibility of the void distribution assessment capability at many existing two-phase test loops.

• 64.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Neutron tomography for void distribution measurements2010Ingår i: ENC 2010 Transactions: Plant Operations, 2010, s. 40-45Konferensbidrag (Övrigt vetenskapligt)

Neutron tomography has previously been performed using large, stationary neutron sources such as reactors and spallation sources for applications where the object under study can be transported to the source. This paper accounts for the challenges met when applying neutron tomography using a portable accelerator driven neutron generator, which is required when studying non-transportable objects. In general, portable sources offer significantly lower neutron yields than stationary sources, implying the need for either longer measurement times or highly efficient measurement and/or analysis procedures.

The particular application investigated here is the mapping of steam distributions in water (void distribution), which is of high importance for the performance of nuclear fuel assemblies in boiling water reactors (BWR). The void distribution cannot be measured directly in a reactor core, so instead various electrically-heated thermal-hydraulic test loops are used. In these loops, void correlations can be determined in full-size fuel-assembly models, such as FRIGG in Sweden and DESIRE in Holland, but measurements are also performed in smaller, less complicated geometries. Previously, gamma tomography has been used to measure the void distribution in the FRIGG loop. However, improved capabilities to map the void distribution can be expected using neutrons because of their higher sensitivity to water relative to metal structures, as compared to gamma rays. At the same time, neutrons as probe also give rise to some challenges, such as high background from scattering.

This paper investigates the possibility to use neutron tomography at axially symmetric objects such as the HWAT test loop in Sweden, where an annular two-phase flow of water/void is confined and heated by a steel cylinder. Monte Carlo simulations of the HWAT geometry and a suggested measurement setup have been carried out, using the particle transport code MCNPX. A reconstruction technique which exploits the symmetries in the test loop has been developed, making it possible to reconstruct the internal void distribution from one single projection. A reconstruction is presented, which is based on simulated data corresponding to a 13-min measurement using a DT source emitting 2∙109 neutrons/s. The reconstruction offers a radial view of the local void fraction in 10 annular sections of HWAT, with uncertainties between 2 and 5 void percent units.

• 65.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Effects of proton escape on detection efficiency in thin scintillator elements and its consequences for optimization of fast-neutron imaging2011Ingår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 651, nr 1, s. 110-116Artikel i tidskrift (Refereegranskat)

Plastic scintillators are commonly used for neutron detection in the MeV energy range, based on n–p scattering and the subsequent deposition of recoil proton's kinetic energy in the detector material. This detection procedure gives a quasi-rectangular energy deposition distribution for mono-energetic neutrons, extending from zero to the neutron energy. However, if the detector sensitive element (DSE) is small, the energy deposition may be incomplete due to the recoil proton escape.

In the application of neutron imaging, here exemplified by fast-neutron tomography, two conflicting requirements have been identified: (1) thin DSEs are required to obtain high spatial resolution and (2) energy discrimination may be required to reduce the influence of neutrons being scattered into the DSEs, which generally occurs at lower energies. However, at small DSE widths, the reduction of energy deposition due to recoil proton escape may cause a significant decrease in detection efficiency when energy discrimination is applied.

In this work, energy deposition distributions in small-size DSEs have been simulated for Deuterium–Deuterium (DD; 2.5 MeV) and Deuterium–Tritium (DT; 14.1 MeV) fusion neutrons. The intrinsic efficiency has been analyzed as a function of energy discrimination level for various detector widths. The investigations show that proton recoil escape causes a significant drop in intrinsic detection efficiency for thin DSEs. For DT neutrons, the drop is 10% at a width of 3.2 mm and 50% at a width of 0.6 mm, assuming an energy threshold at half the incident neutron energy. The corresponding widths for a DD detector are 0.17 and 0.03 mm, respectively.

Finally, implications of the proton escape effect on the design of a fast-neutron tomography device for void distribution measurements at Uppsala University are presented. It is shown that the selection of DSE width strongly affects the instrument design when optimizing for image unsharpness.

• 66.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Correction for dynamic bias error in transmission measurements of void fraction2012Ingår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 83, nr 12, s. 125110-Artikel i tidskrift (Refereegranskat)

Dynamic bias errors occur in transmission measurements, such as X-ray, gamma, or neutron radiography or tomography. This is observed when the properties of the object are not stationary in time and its average properties are assessed. The nonlinear measurement response to changes in transmission within the time scale of the measurement implies a bias, which can be difficult to correct for. A typical example is the tomographic or radiographic mapping of void content in dynamic two-phase flow systems. In this work, the dynamic bias error is described and a method to make a first-order correction is derived. A prerequisite for this method is variance estimates of the system dynamics, which can be obtained using high-speed, time-resolved data acquisition. However, in the absence of such acquisition, a priori knowledge might be used to substitute the time resolved data. Using synthetic data, a void fraction measurement case study has been simulated to demonstrate the performance of the suggested method. The transmission length of the radiation in the object under study and the type of fluctuation of the void fraction have been varied. Significant decreases in the dynamic bias error were achieved to the expense of marginal decreases in precision.

• 67.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Design and initial 1D radiography tests of the FANTOM mobile fast-neutron radiography and tomography system2014Ingår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 756, s. 82-93Artikel i tidskrift (Refereegranskat)

The FANTOM system is a tabletop sized fast-neutron radiography and tomography system newly developed at the Applied Nuclear Physics Division of Uppsala University. The main purpose of the system is to provide time-averaged steam-and-water distribution measurement capability inside the metallic structures of two-phase test loops for Light Water Reactor thermal-hydraulic studies using a portable fusion neutron generator. The FANTOM system provides a set of 1D neutron transmission data, which may be inserted into tomographic reconstruction algorithms to achieve a 2D mapping of the steam-and-water distribution.

In this paper, the selected design of FANTOM is described and motivated. The detector concept is based on plastic scintillator elements, separated for spatial resolution. Analysis of pulse heights on an event-to-event basis is used for energy discrimination. Although the concept allows for close stacking of a large number of detector elements, this demonstrator is equipped with only three elements in the detector and one additional element for monitoring the yield from the neutron generator.

The first measured projections on test objects of known configurations are presented. These were collected using a Sodern Genie 16 neutron generator with an isotropic yield of about 1E8 neutrons per second, and allowed for characterization of the instrument’s capabilities. At an energy threshold of 10 MeV, the detector offered a count rate of about 500 cps per detector element. The performance in terms of spatial resolution was validated by fitting a Gaussian Line Spread Function to the experimental data, a procedure that revealed a spatial unsharpness in good agreement with the predicted FWHM of 0.5 mm.

• 68.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Developments of time-of-flight and proton recoil neutron spectrometry techniques in view of a possible JET DT campaign and for ITER2011Ingår i: 38th EPS Conference on Plasma Physics 2011 (EPS 2011): Europhysics Conference Abstracts, 2011, s. 329-332Konferensbidrag (Refereegranskat)
• 69.
Cypress Semicond Inc, Cork, Ireland.;Univ Cyprus, Dept Elect & Comp Engn, CY-1678 Nicosia, Cyprus..
Single Event Transients and Pulse Quenching Effects in Bandgap Reference Topologies for Space Applications2016Ingår i: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 63, nr 6, s. 2950-2961Artikel i tidskrift (Refereegranskat)

An architectural performance comparison of bandgap voltage reference variants, designed in a 0.18 mu m CMOS process, is performed with respect to single event transients. These are commonly induced in microelectronics in the space radiation environment. Heavy ion tests (Silicon, Krypton, Xenon) are used to explore the analog single-event transients and have revealed pulse quenching mechanisms in analogue circuits. The different topologies are compared, in terms of cross-section, pulse duration and pulse amplitude. The measured results, and the explanations behind the findings, reveal important guidelines for designing analog integrated circuits, which are intended for space applications. The paper includes an analysis on how pulse quenching occurs within the indispensable current mirror, which is used in every analog circuit.

• 70.
Univ Cyprus, Dept Elect & Comp Engn, CY-1678 Nicosia, Cyprus.
Low-Power, Subthreshold Reference Circuits for the Space Environment: Evaluated with -rays, X-rays, Protons and Heavy Ions2019Ingår i: ELECTRONICS, ISSN 2079-9292, Vol. 8, nr 5, artikel-id 562Artikel i tidskrift (Refereegranskat)

The radiation tolerance of subthreshold reference circuits for space microelectronics is presented. The assessment is supported by measured results of total ionization dose and single event transient radiation-induced effects under -rays, X-rays, protons and heavy ions (silicon, krypton and xenon). A high total irradiation dose with different radiation sources was used to evaluate the proposed topologies for a wide range of applications operating in harsh environments similar to the space environment. The proposed custom designed integrated circuits (IC) circuits utilize only CMOS transistors, operating in the subthreshold regime, and poly-silicon resistors without using any external components such as compensation capacitors. The circuits are radiation hardened by design (RHBD) and they were fabricated using TowerJazz Semiconductor's 0.18 m standard CMOS technology. The proposed voltage references are shown to be suitable for high-precision and low-power space applications. It is demonstrated that radiation hardened microelectronics operating in subthreshold regime are promising candidates for significantly reducing the size and cost of space missions due to reduced energy requirements.

• 71. Andreou, Charalambos
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
A Subthreshold, Low-Power, RHBD Reference Circuit, for Earth Observation and Communication Satellites2015Ingår i: Circuits and Systems (ISCAS), 2015 IEEE International Symposium on, 2015, s. 2245-2248Konferensbidrag (Refereegranskat)

A low-power, wide temperature range, radiation tolerant CMOS voltage reference is presented. The proposed reference circuit exhibits a voltage deviation of 0.8mV for 3-MeV protons total ionization dose of 2Mrad and a voltage deviation of 3.8mV for 10-keV X-rays total ionization dose of 4Mrad while being biased at the nominal supply voltage of 0.75V during X-ray irradiation. In addition, the circuit consumes only 4 mu W and exhibits a measured Temperature Drift of 15ppm/degrees C for a temperature range of 190 degrees C (-60 degrees C to 130 degrees C) at the supply voltage of 0.75V. It utilizes only CMOS transistors, operating in the subthreshold regime, and poly-silicon resistors without using any diodes or external components such as compensating capacitors. The circuit is radiation hardened by design (RHBD), it was fabricated using TowerJazz Semiconductor's 0.18 mu m standard CMOS technology and occupies a silicon area of 0.039mm(2). The proposed voltage reference is suitable for high-precision and low-power space applications.

• 72.
Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Genomik. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Genomik.
Mitochondrial sequence analysis for forensic identification using Pyrosequencing technology2002Ingår i: BioTechniques, ISSN 0736-6205, E-ISSN 1940-9818, Vol. 32, nr 1, s. 124-6, 128, 130-3Artikel i tidskrift (Refereegranskat)

Over recent years, requests for mtDNA analysis in the field of forensic medicine have notably increased, and the results of such analyses have proved to be very useful in forensic cases where nuclear DNA analysis cannot be performed. Traditionally, mtDNA has been analyzed by DNA sequencing of the two hypervariable regions, HVI and HVII, in the D-loop. DNA sequence analysis using the conventional Sanger sequencing is very robust but time consuming and labor intensive. By contrast, mtDNA analysis based on the pyrosequencing technology provides fast and accurate results from the human mtDNA present in many types of evidence materials in forensic casework. The assay has been developed to determine polymorphic sites in the mitochondrial D-loop as well as the coding region to further increase the discrimination power of mtDNA analysis. The pyrosequencing technology for analysis of mtDNA polymorphisms has been tested with regard to sensitivity, reproducibility, and success rate when applied to control samples and actual casework materials. The results show that the method is very accurate and sensitive; the results are easily interpreted and provide a high success rate on casework samples. The panel of pyrosequencing reactions for the mtDNA polymorphisms were chosen to result in an optimal discrimination power in relation to the number of bases determined.

• 73. Ankowski, A
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. INFN Milano.
Energy reconstruction of electromagnetic showers from π0 decays with the ICARUS T600 liquid argon TPC2010Ingår i: Acta Physica Polonica B, ISSN 0587-4254, E-ISSN 1509-5770, Vol. 41, nr 1, s. 103-125Artikel i tidskrift (Refereegranskat)

We discuss the ICARUS T600 detector capabilities in electromagnetic shower reconstruction through the analysis of a sample of 212 events, coming from the 2001 Pavia surface test run, of hadronic interactions leading to the production of π0 mesons. Methods of shower energy and shower direction measurements were developed and the invariant mass of the photon pairs was reconstructed. The (γ,γ) invariant mass was found to be consistent with the value of the π0 mass. The resolution of the reconstructed π0 mass was found to be equal to 27.3%. An improved analysis, carried out in order to clean the full event sample from the events measured in the crowded environment, mostly due to the trigger conditions, gave a π0 mass resolution of 16.1%, significantly better than the one evaluated for the full event sample. The trigger requirement of the coincidence of at least four photo-multiplier signals favored the selection of events with a strong pile up of cosmic ray tracks and interactions. Hence a number of candidate π0 events were heavily contaminated by other tracks and had to be rejected. Monte Carlo simulations of events with π0 production in hadronic and neutrino interactions confirmed the validity of the shower energy and shower direction reconstruction methods applied to the real data.

• 74.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Harbin Inst Technol, Sch Chem & Chem Engn, MIIT Key Lab Crit Mat Technol New Energy Convers, Harbin 150001, Heilongjiang, Peoples R China. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
Electrochromic WO3 thin films attain unprecedented durability by potentiostatic pretreatment2019Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 7, nr 6, s. 2908-2918Artikel i tidskrift (Refereegranskat)

Electrochromic windows and glass facades are able to impart energy efficiency jointly with indoor comfort and convenience. Long-term durability is essential for practical implementation of this technology and has recently attracted broad interest. Here we show that a simple potentiostatic pretreatment of sputterdeposited thin films of amorphous WO3-the most widely studied electrochromic material-can yield unprecedented durability for charge exchange and optical modulation under harsh electrochemical cycling in a Li-ion-conducting electrolyte and effectively evades harmful trapping of Li. The pretreatment consisted of applying a voltage of 6.0 V vs. Li/Li+ for several hours to a film backed by a transparent conducting In2O3: Sn layer. Associated compositional and structural modifications were probed by several techniques, and improved durability was associated with elemental intermixing at the WO3/ITO and ITO/glass boundaries as well as with carbonaceous solid-electrolyte interfacial layers on the WO3 films. Our work provides important new insights into long-term durability of ion-exchange-based devices.

• 75.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
Galvanostatic ion de-trapping rejuvenates oxide thin films2015Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 7, nr 48, s. 26387-26390Artikel i tidskrift (Refereegranskat)

Ion trapping under charge insertion-extraction is well-known to degrade the electrochemical performance of oxides. Galvano-static treatment was recently shown capable to rejuvenate the oxide, but the detailed mechanism remained uncertain. Here we report on amorphous electrochromic (EC) WO3 thin films prepared by sputtering and electrochemically cycled in a lithium-containing electrolyte under conditions leading to severe loss of charge exchange capacity and optical modulation span. Time-of-flight elastic recoil detection analysis (ToF-ERDA) documented pronounced Li+ trapping associated with the degradation of the EC properties and, importantly, that Li+ detrapping, caused by a weak constant current drawn through the film for some time, could recover the original EC performance. Thus, ToF-ERDA provided direct and unambiguous evidence for Li+ detrapping.

• 76.
Rhein Westfal TH Aachen, Mat Chem, D-52074 Aachen, Germany.;GTT Technol, Herzogenrath, Germany..
Rhein Westfal TH Aachen, Mat Chem, D-52074 Aachen, Germany.. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Rhein Westfal TH Aachen, Mat Chem, D-52074 Aachen, Germany.. Rhein Westfal TH Aachen, Mat Chem, D-52074 Aachen, Germany.. Rhein Westfal TH Aachen, Mat Chem, D-52074 Aachen, Germany..
Unprecedented thermal stability of inherently metastable titanium aluminum nitride by point defect engineering2017Ingår i: MATERIALS RESEARCH LETTERS, ISSN 2166-3831, Vol. 5, nr 3, s. 158-169Artikel i tidskrift (Refereegranskat)

Extreme cooling rates during physical vapor deposition (PVD) allow growth of metastable phases. However, we propose that reactive PVD processes can be described by a gas-solid paraequilibrium defining chemical composition and thus point defect concentration. Weshow that this notion allows for point defect engineering by controlling deposition conditions. As example we demonstrate that thermal stability of metastable (Ti, Al) Nx, the industrial benchmark coating for wear protection, can be increased from 800 degrees C to unprecedented 1200 degrees C by minimizing the vacancy concentration. The thermodynamic approach formulated here opens a pathway for thermal stability engineering by point defects in reactively deposited thin films.

• 77.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Investigation of the properties of thin films grown via sputtering and resistive thermal evaporation: an Ion Beam Analysis (IBA) study2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)

I det här projektet produceras tunnfilmer med olika metoder i en uppställning för tunnfilmsdeposition och karaktäriseras sedan för att bedöma om maskinen är kapabel att producera filmer av tillräckligt bra kvalitet för att kunna användas i forskningssyften inom jonfysikgruppen på avdelningen för tillämpad kärnfysik på Uppsala Universitet. Både koppar och silverfilmer produceras med magnetronsputtring. Kopparfilmer produceras också med resistiv förångning. Deposition sker på Si(001)-substrat. Filmerna analyseras med Rutherford Backscattering Spectrometry (RBS) och Time of Flight- Elastic Recoil Detection Analysis (ToF-ERDA). Resultaten visar att depositionshastigheten för maskinen är snabbare än det som angetts av företaget som producerar maskinen. Renheten hos filmerna, dvs. koncentrationen av föroreningar, finnes vara inom en acceptabel nivå för forskningstillämpningar med en genomsnittlig syrekontamination på $1.53 \pm 0.05 %$ och kolkontamination på $0.53 \pm 0.02 %$ för sputtrade kopparfilmer. Sputtrade silverfilmer finnes ha en syrekontamination på $0.28 \pm 0.012 %$ och en kolkontamination på $0.41 \pm 0.023 %$. Förångade kopparfilmer finnes att ha en syrekontamination på $0.45 \pm 0.018 %$ och en kolkontamination på $0.31 \pm 0.013 %$. Spår av guld ($\prec 0.5 %$) hittades enbart i sputtrade filmer. Spår av väte kunde också hittas i både sputtrade och förångade filmer. De förångade filmerna finnes ha lägre syrekontamination än de sputtrade filmerna, men tillverkningsprocessen som används i projektet vid tillverkning av förångade filmer är inte lämplig att använda i produktion av tunnfilmer med specifika tjocklekar då det saknas data för att kunna hitta en depositionshastighet. Totalt sett är uppställningen kapabel att producera filmer av adekvat kvalitet för att de ska kunna användas inom avdelningen för produktion av filmer för forskning.

• 78.
Rajiv Gandhi Inst Petr Technol, Dept Phys, Jais, Amethi, India..
Rajiv Gandhi Inst Petr Technol, Dept Phys, Jais, Amethi, India.. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. IAEA, Nucl Phys & Nucl Data Evaluat, Vienna, Austria.
Systematic Nuclear Structure and Nuclear Reaction Studies Relevant to p-process2018Ingår i: Acta Physica Polonica B, ISSN 0587-4254, E-ISSN 1509-5770, Vol. 49, nr 1, s. 27-40Artikel i tidskrift (Refereegranskat)

The cross section and reaction rate of the proton and alpha capture reactions on Pd-102, Te-120, Xe-124,Xe-126, and Ba-130,Ba-132 have been calculated through TALYS in Hauser-Feshbach formalism using relativistic mean field densities. Nuclear structure studies have been also carried out for the nuclei under consideration. Results obtained in the present work for nuclear structure as well as nuclear reaction are in a fair agreement with the available experimental results.

• 79. Balitskii, Olexiy A.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Tuning the Localized Surface Plasmon Resonance in Cu2-xSe Nanocrystals by Postsynthetic Ligand Exchange2014Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 6, nr 20, s. 17770-17775Artikel i tidskrift (Refereegranskat)

Nanoparticles exhibiting localized surface plasmon resonances (LSPR) are valuable tools traditionally used in a wide field of applications including sensing, imaging, biodiagnostics and medical therapy. Plasmonics in semiconductor nanocrystals is of special interest because of the tunability of the carrier densities in semiconductors, and the possibility to couple the plasmonic resonances to quantum confined excitonic transitions. Here, colloidal Cu2-xSe nanocrystals were synthesized, whose composition was shown by Rutherford backscattering analysis and electron dispersive X-ray spectroscopy, to exhibit Cu deficiency. The latter results in p-type doping causing LSPRs, in the present case around a wavelength of 1100 nm, closely matching the indirect band gap of Cu2-xSe. By partial exchange of the organic ligands to specific electron trapping or donating species the LSPR is fine-tuned to exhibit blue or red shifts, in total up to 200 nm. This tuning not only provides a convenient tool for post synthetic adjustments of LSPRs to specific target wavelength but the sensitive dependence of the resonance wavelength on surface charges makes these nanocrystals also interesting for sensing applications, to detect analytes dressed by functional groups.

• 80. Bansah, C. Y.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Theoretical model for predicting the relative timings of potential failures in steam generator tubes of a PWR during a severe accident2013Ingår i: Annals of Nuclear Energy, ISSN 0306-4549, E-ISSN 1873-2100, Vol. 59, s. 10-15Artikel, forskningsöversikt (Refereegranskat)

During certain severe reactor accidents such as station-blackout accidents, countercurrent natural circulation flow could develop within the reactor coolant system. Natural circulation flow is very important because of transfer of decay energy from the core to other parts of the reactor coolant system. The associated heat-ups of the reactor coolant system structures can lead to pressure boundary failures with notable vulnerabilities in the pressurizer surge line, the hot leg nozzles and the steam generator tubes. The potential for a steam generator tube failure has been of particular concern because fission products could be released to the environment through such a failure. To solve the problem of steam generator tube failure, a computer code - Steam Generator Mitigation Program (SGMP), written in FORTRAN 95 computes the recirculation ratio (RR) and the mixing fraction (MF) which are the main parameters used in characterizing natural circulation. In the flow analysis, the RR and MF were respectively found to be 2.4 +/- 0.3 and 0.8 +/- 0.17. The results obtained showed that the natural circulation would delay the failure time of the steam generator tubes and is in good qualitative agreement with results from literature.

• 81. Batistoni, P.
14 MeV calibration of JET neutron detectors-phase 1: calibration and characterization of the neutron source2018Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 58, nr 2, artikel-id UNSP 026012Artikel i tidskrift (Refereegranskat)

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

• 82.
ENEA, Dipartimento Fus & Sicurezza Nucl, Via E Fermi 45, I-00044 Frascati, Roma, Italy..
CCFE, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England.. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. CCFE, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England.. Karlsruhe Inst Technol, POB 3640, D-76021 Karlsruhe, Germany.. CCFE, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England.. CCFE, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England.. Jozef Stefan Inst, Reactor Phys Dept, Jamova 39, SI-1000 Ljubljana, Slovenia.. CCFE, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England.. Culham Sci Ctr, JET Exploitat Unit, Abingdon OX14 3DB, Oxon, England.. ENEA, Dipartimento Fus & Sicurezza Nucl, Via E Fermi 45, I-00044 Frascati, Roma, Italy.. CCFE, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England.. CCFE, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England.. CIEMAT, Lab Nacl Fus, Madrid, Spain.. ENEA, Dipartimento Fus & Sicurezza Nucl, Via E Fermi 45, I-00044 Frascati, Roma, Italy.. EUROfus Consortium, Culham Sci Ctr, ITER Phys Dept, Abingdon OX14 3DB, Oxon, England..
Technological exploitation of Deuterium-Tritium operations at JET in support of ITER design, operation and safety2016Ingår i: Fusion engineering and design, ISSN 0920-3796, E-ISSN 1873-7196, Vol. 109, s. 278-285Artikel i tidskrift (Refereegranskat)

Within the framework of the EUROfusion programme, a work-package of technology projects (WPJET3) is being carried out in conjunction with the planned Deuterium-Tritium experiment on JET (DTE2) with the objective of maximising the scientific and technological return of DT operations at JET in support of ITER. This paper presents the progress since the start of the project in 2014 in the preparatory experiments, analyses and studies in the areas of neutronics, neutron induced activation and damage in ITER materials, nuclear safety, tritium retention, permeation and outgassing, and waste production in preparation of DTE2.

• 83. Batistoni, P.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Benchmark experiments on neutron streaming through JET Torus Hall penetrations2015Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 55, nr 5, artikel-id 053028Artikel i tidskrift (Refereegranskat)

Neutronics experiments are performed at JET for validating in a real fusion environment the neutronics codes and nuclear data applied in ITER nuclear analyses. In particular, the neutron fluence through the penetrations of the JET torus hall is measured and compared with calculations to assess the capability of state-of-art numerical tools to correctly predict the radiation streaming in the ITER biological shield penetrations up to large distances from the neutron source, in large and complex geometries. Neutron streaming experiments started in 2012 when several hundreds of very sensitive thermo-luminescence detectors (TLDs), enriched to different levels in (LiF)-Li-6/(LiF)-Li-7, were used to measure the neutron and gamma dose separately. Lessons learnt from this first experiment led to significant improvements in the experimental arrangements to reduce the effects due to directional neutron source and self-shielding of TLDs. Here we report the results of measurements performed during the 2013-2014 JET campaign. Data from new positions, at further locations in the South West labyrinth and down to the Torus Hall basement through the air duct chimney, were obtained up to about a 40m distance from the plasma neutron source. In order to avoid interference between TLDs due to self-shielding effects, only TLDs containing natural Lithium and 99.97% Li-7 were used. All TLDs were located in the centre of large polyethylene (PE) moderators, with Li-nat and Li-7 crystals evenly arranged within two PE containers, one in horizontal and the other in vertical orientation, to investigate the shadowing effect in the directional neutron field. All TLDs were calibrated in the quantities of air kerma and neutron fluence. This improved experimental arrangement led to reduced statistical spread in the experimental data. The Monte Carlo N-Particle (MCNP) code was used to calculate the air kerma due to neutrons and the neutron fluence at detector positions, using a JET model validated up to the magnetic limbs. JET biological shield and penetrations, the PE moderators and TLDs were modelled in detail. Different tallying methods were used in the calculations, which are routinely used in ITER nuclear analyses: the mesh tally and the track length estimator with multiple steps calculations using the surface source write/read capability available in MCNP. In both cases, the calculated neutron fluence (C) was compared to the measured fluence (E) and hence C/E comparisons have been obtained and are discussed. These results provide a validation of neutronics numerical tools, codes and nuclear data, used for ITER design.

• 84. Batistoni, P.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
14 MeV calibration of JET neutron detectors-phase 2: in-vessel calibration2018Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 58, nr 10, artikel-id 106016Artikel i tidskrift (Refereegranskat)

A new DT campaign (DTE2) is planned at JET in 2020 to minimize the risks of ITER operations. In view of DT operations, a calibration of the JET neutron monitors at 14 MeV neutron energy has been performed using a well calibrated 14 MeV neutron generator (NG) deployed, together with its power supply and control unit, inside the vacuum vessel by the JET remote handling system. The NG was equipped with two calibrated diamond detectors, which continuously monitored its neutron emission rate during the calibration, and activation foils which provided the time integrated yield. Cables embedded in the remote handling boom were used to power the neutron generator, the active detectors and pre-amplifier, and to transport the detectors' signal. The monitoring activation foils were retrieved at the end of each day for decay gamma-ray counting, and replaced by fresh ones. About 76 hours of irradiation, in 9 days, were needed with the neutron generator in 73 different poloidal and toroidal positions in order to calibrate the two neutron yield measuring systems available at JET, the U-235 fission chambers (KN1) and the inner activation system (KN2). The NG neutron emission rates provided by the monitoring detectors were in agreement within 3%. Neutronics calculations have been performed using MCNP code and a detailed model of JET to derive the response of the JET neutron detectors to DT plasma neutrons starting from the response to the NG neutrons, and taking into account the anisotropy of the neutron generator and all the calibration circumstances. These calculations have made use of a very detailed and validated geometrical description of the neutron generator and of the modified. MNCP neutron source subroutine producing neutron energy-angle distribution for the neutrons emitted by the NG. The KN1 calibration factor for a DT plasma has been determined with +/- 4.2%' experimental uncertainty. Corrections due to NG and remote handling effects and the plasma volume effect have been calculated by simulation modelling. The related additional uncertainties are difficult to estimate, however the results of the previous calibration in 2013 have demonstrated that such uncertainties due to modelling are globally <= +/- 3%. It has been found that the difference between KN1 response to DD neutrons and that to DT neutrons is within the uncertainties in the derived responses. KN2 has been calibrated using the Nb-93(n,2n)Nb-92m and Al-27(n,a)Na-24 activation reactions (energy thresholds 10 MeV and 5 MeV respectively). The total uncertainty on the calibration factors is +/- 6% for Nb-93(n,2n)Nb-92m and +/- 8% Al-27(n,a)Na-24 (1 sigma). The calibration factors of the two independent systems KN1 and KN2 will be validated during DT operations. The experience gained and the lessons learnt are presented and discussed in particular with regard to the 14 MeV neutron calibrations in ITER.

• 85.
ENEA, Dept Fus & Technol Nucl Safety & Secur, I-00044 Frascati, Rome, Italy..
Culham Sci Ctr, CCFE, Abingdon OX14 3DB, Oxon, England.. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Jozef Stefan Inst, Reactor Phys Div, Jamova Cesta 39, SI-1000 Ljubljana, Slovenia.. Jozef Stefan Inst, Reactor Phys Div, Jamova Cesta 39, SI-1000 Ljubljana, Slovenia.. Inst Plasma Res, Gandhinagar 382428, Gujarat, India.. Jozef Stefan Inst, Reactor Phys Div, Jamova Cesta 39, SI-1000 Ljubljana, Slovenia.. Culham Sci Ctr, JET Exploitat Unit, Abingdon OX14 3DB, Oxon, England..
Calibration of neutron detectors on the Joint European Torus2017Ingår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 88, nr 10, artikel-id 103505Artikel i tidskrift (Refereegranskat)

The present paper describes the findings of the calibration of the neutron yield monitors on the Joint European Torus (JET) performed in 2013 using a Cf-252 source deployed inside the torus by the remote handling system, with particular regard to the calibration of fission chambers which provide the time resolved neutron yield from JET plasmas. The experimental data obtained in toroidal, radial, and vertical scans are presented. These data are first analysed following an analytical approach adopted in the previous neutron calibrations at JET. In this way, a calibration function for the volumetric plasma source is derived which allows us to understand the importance of the different plasma regions and of different spatial profiles of neutron emissivity on fission chamber response. Neutronics analyses have also been performed to calculate the correction factors needed to derive the plasma calibration factors taking into account the different energy spectrum and angular emission distribution of the calibrating (point) Cf-252 source, the discrete positions compared to the plasma volumetric source, and the calibration circumstances. All correction factors are presented and discussed. We discuss also the lessons learnt which are the basis for the on-going 14 MeV neutron calibration at JET and for ITER.

• 86. Battistoni, G
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
FLUKA Monte Carlo calculations for hadrontherapy application2013Ingår i: CERN-Proceedings-2012-002, 2013, s. 461-467Konferensbidrag (Refereegranskat)

Monte Carlo (MC) codes are increasingly spreading in the hadrontherapy community due to their detailed description of radiation transport and interaction with matter. The suitability of a MC code for application to hadrontherapy demands accurate and reliable physical models for the description of the transport and the interaction of all components of the expected radiation field (ions, hadrons, electrons, positrons and photons). This contribution will address the specific case of the general-purpose particle and interaction code FLUKA. In this work, an application of FLUKA will be presented, i.e. establishing CT (computed tomography)-based calculations of physical and RBE (relative biological effectiveness)-weighted dose distributions in scanned carbon ion beam therapy.

• 87. Battistoni, G.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. INFN Milano, Chalmers University of Technology.
The FLUKA code and its use in hadron therapy2008Ingår i: Nuovo Cimento C Geophysics Space Physics C, Vol. 31, nr 1, s. 69-75Artikel i tidskrift (Refereegranskat)

FLUKA is a multipurpose Monte Carto code describing transport and interaction with matter of a, large variety of particles over a wide energy range ill complex geometries. FLUKA is successfully applied ill several fields, including, but not only particle physics, cosmic-ray physics, dosimetry, radioprotection, hadron therapy. space radiation, accelerator design and neutronics. Here we briefly review recent model developments and provide examples of applications to hadron therapy, including calculation of physical and biological dose for comparison with analytical treatment planning engines as well as beta(+)-activation for therapy monitoring by means of positron emission tomography.

• 88. Battistoni, G.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. INFN Milano, Chalmers University of Technology.
Secondary Cosmic Ray Particles due to GCR Interactions in the Earth’s Atmosphere2008Ingår i: Exotic Nuclei and Nuclear/Particle Astrophysics (II), American Institute of Physics, 2008, Vol. 972, s. 449-454Konferensbidrag (Refereegranskat)

Primary GCR interact with the Earth's atmosphere originating atmospheric showers, thus giving rise to fluxes of secondary particles in the atmosphere. Electromagnetic and hadronic interactions interplay in the production of these particles, whose detection is performed by means of complementary techniques in different energy ranges and at different depths in the atmosphere, down to the Earth's surface.

Monte Carlo codes are essential calculation tools which can describe the complexity of the physics of these phenomena, thus allowing the analysis of experimental data. However, these codes are affected by important uncertainties, concerning, in particular, hadronic physics at high energy. In this paper we shall report some results concerning inclusive particle fluxes and atmospheric shower properties as obtained using the FLUKA transport and interaction code. Some emphasis will also be given to the validation of the physics models of FLUKA involved in these calculations.

• 89. Battistoni, G.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. RIKEN Nishina Center.
Generator of neutrino-nucleon interactions for the FLUKA based simulation code2009Ingår i: American Institute of Physics Conference Series, American Institute of Physics, 2009, Vol. 1189, s. 343-346Konferensbidrag (Refereegranskat)

An event generator of neutrino-nucleon and neutrino-nucleus interactions has been developed for the general purpose Monte Carlo code FLUKA. The generator includes options for simulating quasi-elastic interactions, the neutrino-induced resonance production and deep inelastic scattering. Moreover, it shares the hadronization routines developed earlier in the framework of the FLUKA package for simulating hadron-nucleon interactions. The simulation of neutrino-nuclear interactions makes use of the well developed PEANUT event generator implemented in FLUKA for modeling of the interactions between hadrons and nuclei. The generator has been tested in the neutrino energy range from 0 to 10 TeV and it is available in the standard FLUKA distribution. Limitations related to some particular kinematical conditions are discussed. A number of upgrades is foreseen for the generator which will optimize its applications for simulating experiments in the CNGS beam.

• 90. Battistoni, G.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. RIKEN Nishina Center.
Neutrino Interactions with FLUKA2009Ingår i: Acta Physica Polonica B, ISSN 0587-4254, E-ISSN 1509-5770, Vol. 40, nr 9, s. 2491-2505Artikel i tidskrift (Refereegranskat)

A new neutrino interaction generator has been developed in FLUKA. The package, called NUNDIS (NeUtrino–Nucleon Deep Inelastic Scattering), is specifically built in order to be fully integrated with the hadronization and nuclear models of the FLUKA Monte Carlo code which were already successfully tested in hadronic interactions. This generator thus complements the already existing generator of quasi-elastic neutrino scattering. Here we describe the physics, sampling methods, and other specifics of NUNDIS, as well as the limitations of the code.

• 91. Battistoni, Giuseppe
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
FLUKA Capabilities and CERN Applications for the Study of Radiation Damage to Electronics at High-Energy Hadron Accelerators2011Konferensbidrag (Refereegranskat)

The assessment of radiation damage to electronics is a complex process and requires a detailed description of the full particle energy spectra, as well as a clear characterization of the quantities used to predict radiation damage. FLUKA, a multi-purpose particle interaction and transport code, is capable of calculating proton-proton and heavy ion collisions at LHC energies and beyond. It correctly describes the entire hadronic and electromagnetic particle cascade initiated by secondary particles from TeV energies down to thermal neutrons, and provides direct scoring capabilities essential to estimate in detail the possible risk of radiation damage to electronics. This paper presents the FLUKA capabilities for applications related to radiation damage to electronics, providing benchmarking examples and showing the practical applications of FLUKA at CERN facilities such as CNGS and LHC. Related applications range from the study of device effects, the detailed characterization of the radiation field and radiation monitor calibration, to the input requirements for important mitigation studies including shielding, relocation or other options.

• 92. Battistoni, Giuseppe
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
The Application of the Monte Carlo Code FLUKA in Radiation Protection Studies for the Large Hadron Collider2011Konferensbidrag (Refereegranskat)

The multi-purpose particle interaction and transport code FLUKA is integral part of all radiation protection studies for the design and operation of the Large Hadron Collider (LHC) at CERN. It is one of the very few codes available for this type of calculations which is capable to calculate in one and the same simulation proton-proton and heavy ion collisions at LHC energies as well as the entire hadronic and electromagnetic particle cascade initiated by secondary particles in detectors and beam-line components from TeV energies down to energies of thermal neutrons. The present paper reviews these capabilities of FLUKA in sketching the relevant physics models along with examples ofradiation protection studies for the LHC such as shielding studies for underground areas occupied by personnel during LHC operation and the simulation of induced radioactivity around beam loss points. Integral part of the FLUKA development is a careful benchmarking of specific models as well as the code performance in actual, complex applications which is demonstrated with examples of studies relevant to radiation protection at the LHC.

• 93.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
PWR fuel of high enrichment with erbia and enriched gadolinia2011Konferensbidrag (Refereegranskat)
• 94. Belli, Francesco
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Conceptual Design, Development and Preliminary Tests of a Compact Neutron Spectrometer for the JET Experiment2012Ingår i: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 59, nr 5, s. 2512-2519Artikel i tidskrift (Refereegranskat)

A Compact Neutron Spectrometer (CNS) has been developed to measure the neutron emission spectra in Joint European Torus (JET) fusion plasma experiments. The spectrometer, based on a liquid scintillation detector (BC501A), is equipped with a Digital Pulse Shape Discrimination (DPSD) acquisition system for neutron (n) and gamma-ray(gamma) separation. The CNS enables recording the n and gamma pulse height spectra (PHS) up to total count rates of similar to 10(6) s(-1). Energy resolution, after PHS unfolding, will be <2% for 14 MeV neutrons and <4% for 2.5 MeV neutrons. The work done by ENEA-Frascati and Physikalisch-Technische Bundesanstalt (PTB) respectively in the assembly and test of DPSD and scintillation detector, along with the first results obtained by the spectrometer in JET plasma experiments are presented. The experience obtained with CNS in JET will contribute to the development of neutron spectrometers suitable for applications in the International Thermonuclear Experimental Reactor (ITER).

• 95.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
Evaluation of a microplasma source based on a stripline split-ring resonator2013Ingår i: Plasma sources science & technology (Print), ISSN 0963-0252, E-ISSN 1361-6595, Vol. 22, nr 5, s. 055017-Artikel i tidskrift (Refereegranskat)

In this paper, a stripline split-ring resonator microwave-induced plasma source, aimed for integration in complex systems, is presented and compared with a traditional microstrip design. Devices based on the two designs are evaluated using a plasma breakdown test setup for measuring the power required to ignite plasmas at different pressures. Moreover, the radiation efficiency of the devices is investigated with a Wheeler cap, and their electromagnetic compatibility is investigated in a variable electrical environment emulating an application. Finally, the basic properties of the plasma in the two designs are investigated in terms of electron temperature, plasma potential and ion density. The study shows that, with a minor increase in plasma ignition power, the stripline design provides a more isolated and easy-to-integrate alternative to the conventional microstrip design. Moreover, the stripline devices showed a decreased antenna efficiency as compared with their microstrip counterparts, which is beneficial for plasma sources. Furthermore, the investigated stripline devices exhibited virtually no frequency shift in a varying electromagnetic environment, whereas the resonance frequency of their microstrip counterparts shifted up to 17.5%. With regard to the plasma parameters, the different designs showed only minor differences in electron temperature, whereas the ion density was higher with the stripline design.

• 96.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
Operation characteristics and optical emission distribution of a miniaturized silicon through-substrate split-ring resonator microplasma source2014Ingår i: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 23, nr 6, s. 1340-1345Artikel i tidskrift (Refereegranskat)

There are many new microplasma sources being developed for a wide variety of applications, each with different properties tailored to its specific use. Microplasma sources enable portable instruments for, e.g., chemical analysis, sterilization, or activation of substances. A novel microplasma source, based on a microstrip split-ring resonator design with electrodes integrated in its silicon substrate, was designed, manufactured, and evaluated. This device has a plasma discharge gap with a controlled volume and geometry, and offers straightforward integration with other microelectromechancial systems (MEMS) components, e.g., microfluidics. The realized device was resonant at around 2.9 GHz with a quality factor of 18.7. Two different operational modes were observed with the plasma at high pressure being confined in the gap between the electrodes, whereas the plasma at low pressures appeared between the ends of the electrodes on the backside. Measurement of the angular distribution of light emitted from the device with through-substrate electrodes showed narrow emission lobes compared with a reference plasma source with on-substrate electrodes.

• 97. Bergmann, Olaf
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi.
Dynamics of Cell Generation and Turnover in the Human Heart2015Ingår i: Cell, ISSN 0092-8674, E-ISSN 1097-4172, Vol. 161, nr 7, s. 1566-1575Artikel i tidskrift (Refereegranskat)

The contribution of cell generation to physiological heart growth and maintenance in humans has been difficult to establish and has remained controversial. We report that the full complement of cardiomyocytes is established perinataly and remains stable over the human lifespan, whereas the numbers of both endothelial and mesenchymal cells increase substantially from birth to early adulthood. Analysis of the integration of nuclear bomb test-derived C-14 revealed a high turnover rate of endothelial cells throughout life (>15% per year) and more limited renewal of mesenchymal cells (<4% per year in adulthood). Cardiomyocyte exchange is highest in early childhood and decreases gradually throughout life to <1% per year in adulthood, with similar turnover rates in the major subdivisions of the myocardium. We provide an integrated model of cell generation and turnover in the human heart.

• 98.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Neutron-Induced Light-Ion Production from Iron and Bismuth at 175 MeV2011Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)

Radioactive waste management is one of the key issues in sustainability of nuclear energy production. Geological repositories represent today the most appropriate solution to long-term management of high-level radioactive waste. Strategies such as Partitioning and Transmutation of spent nuclear fuel may offer a positive impact on geological repositories, by reducing the mass of transuranium elements to be disposed and the time scale for their radiotoxicity. In this scenario, Accelerator Driven Systems (ADS) may play a relevant role as dedicated burners towards sustainable nuclear energy.

The NEXT project at Uppsala University contributes to a European effort to improve nuclear data knowledge for transmutation, providing the first experimental neutron induced data in the 100 to 200 MeV energy region. This thesis presents measurements of double-differential cross sections for production of light-ions in the interaction of 175 MeV quasi-monoenergetic neutrons with Fe and Bi. Results are compared with model calculations obtained with state-of-the-art nuclear reaction codes; TALYS-1.2, a modified version of JQMD, and MCNP6. Special focus in this work is given to pre-equilibrium emission of composite light-ions. A new energy dependence in the mechanisms described by the Kalbach systematics used in TALYS to account for composite particle emission in the pre-equilibrium stage is proposed. Data show also the need to include multiple pre-equilibrium emission of composite particles, a mechanism now included in TALYS only for protons and neutrons. The JQMD code was recently modified to include a surface coalescence model in the quantum molecular dynamics description of the formation of composite particles. Comparisons of the measured data with results from this modified JQMD code confirm the importance of coalescence mechanisms for the description of the emission spectra of composite particles. Finally, the neutron-induced data are compared with MCNP6 calculations, to contribute to the process of validation and verification of the code.

• 99.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
New neutron data measurements at 175 MeV for Accelerator Driven Systems2011Ingår i: Proceedings of the 2011 International Congress on Advances in Nuclear Power Plants: Performance & Flexibility: The Power of Innovation, 2011, s. 2828-2834Konferensbidrag (Refereegranskat)

We have compared TALYS, MCNP6 and quantum molecular dynamics model calculations with preliminary light-ion production data in the interaction of 175 MeV quasi-monoenergetic neutrons with Fe and Bi. Data were measured with the Medley setup at the The Svedberg Laboratory, in Uppsala – Sweden. These are the first neutron induced light-ion production data available in the 100 to 200 MeV energy region; these data are relevant for the development of accelerator-driven system technologies, and are needed to ensure a link between high and low energy processes. Model calculations are consistent with some results, but at the moment no code is able to fully predict  all the experimental data. Our results show the need of further investigation of neutron-induced reactions in this energy region, in particular to study the production of composite light ions.

• 100.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik. Uppsala universitet, The Svedberg-laboratoriet.
Study of pre-equilibrium emission of light complex particles from Fe and Bi induced by intermediate energy neutrons2011Ingår i: International Nuclear Physics Conference 2010: Nuclear Reactions, 2011, s. 082013-Konferensbidrag (Refereegranskat)

We have measured double differential cross sections (DDX) for emission of hydrogen- and helium-isotopes in the interaction of 175 MeV quasi-monoenergetic neutrons with Fe and Bi using the Medley setup at the The Svedberg Laboratory (Uppsala, Sweden). We compared experimental DDX with calculations with the TALYS code, which includes exciton model and Kalbach systematics; the code fails to reproduce the emission of complex light-ions, generally overestimating it. We propose an correction for the application of the Kalbach phenomenological model in the TALYS code by introducing a new energy dependence for the nucleon transfer mechanism in the pre-equilibrium emission region. Our results suggest also evidence for multiple pre-equilibrium emission of composite particles at 175 MeV.

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