| 1. |
- Andersson, P., et al.
(författare)
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An upgrade of the SCANDAL setup for measurements of elastic neutron scattering at 175 MeV
- 2010
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Ingår i: RADIATION MEASUREMENTS. - : Elsevier BV. ; 45:10, s. 1142-1144
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Konferensbidrag (refereegranskat)abstract
- The experimental setup SCANDAL used for measurements of the differential cross section for elastic and inelastic neutron scattering, has recently been upgraded with larger CsI scintillating detectors to enable measurements at energies up to 175 MeV. Measurements on Fe. Bi and Si have been carried out using the quasi mono-energetic neutron beam at the The Svedberg Laboratory, and data is under analysis. The experimental setup can be used for measurements on a wide range of target nuclei, including C and O, which are important for dosimetry applications. SCANDAL can also run in proton mode, for measurements of the (n,p) reaction. This paper describes the new experimental setup, and reports on its properties, such as energy resolution.
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| 2. |
- Bevilacqua, Riccardo, et al.
(författare)
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Light-ion Production from O, Si, Fe and Bi Induced by 175 MeV Quasi-monoenergetic Neutrons
- 2014
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Ingår i: Nuclear Data Sheets. - : Elsevier BV. - 0090-3752 .- 1095-9904. ; 119, s. 190-193
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Tidskriftsartikel (refereegranskat)abstract
- We have measured double-differential cross sections in the interaction of 175 MeV quasimonoenergetic neutrons with O, Si, Fe and Bi. We have compared these results with model calculations with INCL4.5-Abla07, MCNP6 and TALYS-1.2. We have also compared our data with PHITS calculations, where the pre-equilibrium stage of the reaction was accounted respectively using the JENDL/HE-2007 evaluated data library, the quantum molecular dynamics model (QMD) and a modified version of QMD (MQMD) to include a surface coalescence model. The most crucial aspect is the formation and emission of composite particles in the pre-equilibrium stage.
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| 3. |
- Bevilacqua, Riccardo, et al.
(författare)
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Light-Ion Production in the Interaction of 175 MeV Neutrons with Iron and Bismuth
- 2011
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Ingår i: Journal of the Korean Physical Society. - : Korean Physical Society. - 0374-4884 .- 1976-8524. ; 59:2, s. 1701-1704
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Tidskriftsartikel (refereegranskat)abstract
- We have measured double-differential (angle and energy) cross sections for light-ion (p, d, t, (3)He, and a) production in the interaction of quasi-monoenergetic 175 MeV neutrons with iron and bismuth. Measurements have been performed at the The Svedberg Laboratory, Uppsala (Sweden), using the Medley setup which allows low-energy thresholds and wide energy and angular ranges. Medley is a spectrometer system consisting of eight three-element telescopes placed at angles from 20 degrees to 160 degrees, in steps of 20 degrees. Each telescope is composed of two silicon surface barrier detectors and a CsI(Tl) scintillator, to perform particle identification, fully stop the produced light-ions and measure their kinetic energy. The time-of-flight was used to reduce the contribution from the low energy tail in the accepted incident neutron spectrum. We report double-differential production cross sections for protons, deuterons, tritons, (3)He and alpha particles and compare them with model calculations with TALYS-1.2.
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| 4. |
- Bevilacqua, Riccardo, 1974-, et al.
(författare)
-
Light-ion production in the interaction of 175 MeV neutrons with iron and bismuth
- 2011
-
Ingår i: Journal of Korean Physical Society.
-
Konferensbidrag (refereegranskat)abstract
- We have measured double-differential (angle and energy) cross sections for light-ion (p, d, t, 3He and α) production in the interaction of quasi-monoenergetic 175 MeV neutrons with iron and bismuth. Measurements have been performed at the The Svedberg Laboratory, Uppsala (Sweden), using the Medley setup which allows low-energy thresholds and wide energy and angular ranges. Medley is a spectrometer system consisting of eight three-element telescopes placed at angles from 20◦ to 160◦, in steps of 20◦. Each telescope is composed of two silicon surface barrier detectors and a CsI(Tl) scintillator, to perform particle identification,fully stop the produced light-ions and measure their kinetic energy. The time-of-flight was used to reduce the contribution from the low energy tail in the accepted incident neutron spectrum. We report double-differential production cross sections for protons, deuterons, tritons, 3He and α particles and compare them with model calculations with TALYS-1.2.
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| 5. |
- Bevilacqua, Riccardo, et al.
(författare)
-
Neutron induced light-ion production from iron and bismuth at 175 MeV
- 2010
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Ingår i: RADIATION MEASUREMENTS. - : Elsevier BV. ; 45:10, s. 1145-1150
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Konferensbidrag (refereegranskat)abstract
- We have measured light-ion (p, d, t, He-3 and alpha) production in the interaction of 175 MeV neutrons with iron and bismuth with low-energy thresholds and for a wide angular range (from 20 degrees to 160 degrees, in steps of 20 degrees). Measurements have been performed with the Medley setup, semi-permanently installed at the The Svedberg Laboratory, Uppsala (Sweden), where a quasi-monoenergetic neutron beam is available and well characterized. Medley is a conventional spectrometer system and consists of eight telescopes, each of them composed of two silicon surface barrier detectors, to perform particle identification, and a CsI(Tl) scintillator to fully measure the kinetic energy of the produced light-ions. We report preliminary double-differential cross sections for production of protons, deuterons and tritons in comparison with model calculations using TALYS-1.0 code. These show better agreement for the production of protons, while the theoretical calculations seem to overestimate the experimental production of deuterons and tritons.
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| 6. |
- Gustavsson, Cecilia, Dr, 1973-, et al.
(författare)
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Citizen science in radiation research
- 2020
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Ingår i: ND 2019. - : EDP Sciences. - 9782759891061
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Konferensbidrag (refereegranskat)abstract
- A growing trend in science is that research institutions reach out to members of the public for participating in research. The reasons for outreach are many, spanning from the desire to collect and/or analyse large sets of data efficiently, to the idea of including the general public on a very fundamental level in science-making and ultimately decision-making. The presented project is curriculum-based and carried out in 240 lower secondary school classes (pupils of age 13-16). The task, as designed by the participating universities, is to collect mushrooms, soil and animal droppings from different parts of Sweden, do preliminary sample preparation and analyses and send the samples to the university institutions for radioactivity measurement. Behind the project is a desire to compare today’s levels of 137Cs with those deposited right after the Chernobyl accident in 1986, but also to study the exchange of caesium between organisms as well as the impacts of biological and geological processes on uptake and retention. The scientific outcome is a geodatabase with the 137Cs activity (Bq/m2) present in the Swedish environment, where radioactivity data can be linked to the species (fungi, competing species, animals foraging), forest type, land type, land use and other environmental factors. The science question is of interest to the general public as foraging for mushrooms, as well as spending recreational time in forests is widely popular in Sweden. In this article, we will discuss the current status of the project and the observations we have made about how well the public can participate in scientific research. Focus will be on organization of the project, such as logistics, preparation of supportive material, feedback and communication between researchers and schools. We will present observations about the impact the project has had on the participants, based on quantitative and qualitative evaluations.
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| 7. |
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| 8. |
- Hirayama, S., et al.
(författare)
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Light-ion Production from a Thin Silicon Target Bombarded by 175 MeV Quasi Mono-energetic Neutrons
- 2011
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Ingår i: Journal of the Korean Physical Society. - : Korean Physical Society. - 0374-4884 .- 1976-8524. ; 59:2, s. 1447-1450
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Tidskriftsartikel (refereegranskat)abstract
- Double-differential production yields of light ions (p, d, t, (3)He, and alpha) from a thin silicon target induced by 175 MeV quasi mono-energetic neutrons were measured using the MEDLEY setup at the The Svedberg Laboratory (TSL) in Uppsala in order to benchmark evaluated nuclear data and nuclear reaction models. The MEDLEY is a conventional spectrometer system which consists of eight counter telescopes. Each telescope is composed of two silicon surface barrier detectors as the Delta E detectors and a CsI(Tl) scintillator as the E detector for particle identification. The telescopes are placed at angles from 20 degrees to 160 degrees in steps of 20 degrees. The measured double-differential yields of light ions are compared with PHITS calculations using the following nuclear reaction options: the high-energy nuclear data library (JENDL/HE-2007), the quantum molecular dynamics (QMD) model, and the intra-nuclear cascade (INC) model.
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| 9. |
- Jansson, Kaj, et al.
(författare)
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Designing an upgrade of the Medley setup for light-ion production and fission cross-section measurements
- 2015
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 794, s. 141-150
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Measurements of neutron-induced fission cross-sections and light-ion production are planned in the energy range 1-40 MeV at the upcoming Neutrons For Science (NFS) facility. In order to prepare our detector setup for the neutron beam with continuous energy spectrum, a simulation software was written using the Geant4 toolkit for both measurement situations. The neutron energy range around 20 MeV is troublesome when it comes to the cross-sections used by Geant4 since data-driven cross-sections are only available below 20 MeV but not above, where they are based on semi-empirical models. Several customisations were made to the standard classes in Geant4 in order to produce consistent results over the whole simulated energy range. Expected uncertainties are reported for both types of measurements. The simulations have shown that a simultaneous precision measurement of the three standard cross-sections H(n,n), 235U(n,f) and 238U(n,f) relative to each other is feasible using a triple layered target. As high resolution timing detectors for fission fragments we plan to use Parallel Plate Avalanche Counters (PPACs). The simulation results have put some restrictions on the design of these detectors as well as on the target design. This study suggests a fissile target no thicker than 2 µm (1.7 mg/cm2) and a PPAC foil thickness preferably less than 1 µm . We also comment on the usability of Geant4 for simulation studies of neutron reactions in this energy range.
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| 10. |
- Lantz, Mattias, 1971-, et al.
(författare)
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Gamma spectroscopy methodology for large amounts of environmental samples in Sweden 30 years after the Chernobyl accident
- 2020
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Ingår i: ND 2019. - : EDP Sciences. - 9782759891061
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Konferensbidrag (refereegranskat)abstract
- In a Swedish citizen science project, more than 200 elementary school classes participated in collecting fungi, soil samples, and droppings from deer and wild boar, from all over Sweden. The samples have been sent to a laboratory at Uppsala University where they are being analyzed through gamma spectroscopy with a shielded HPGe detector. The main objective is to scan the samples for 137Cs from the Chernobyl accident and compare the data with measurements from 1986, but uptake of naturally occuring radionuclides like 40K and radon daughters will also be determined. Together with the soil samples, transfer factors will be derived, and correlations for these factors will be sought for different species of fungi and soil types. The potential for correlating the results with different biological processes will also be investigated, in part through the collected animal droppings. This is a work in progress where the present status of the experimental setup and methodology are presented. Issues with the initial approach for corrections are discussed and preliminary results are presented.
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