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Sökning: WFRF:(Moszynski M.)

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1.
  • Sherratt, K., et al. (författare)
  • Predictive performance of multi-model ensemble forecasts of COVID-19 across European nations
  • 2023
  • Ingår i: eLIFE. - : eLife Sciences Publications Ltd. - 2050-084X. ; 12
  • Tidskriftsartikel (refereegranskat)abstract
    • Methods: We used open-source tools to develop a public European COVID-19 Forecast Hub. We invited groups globally to contribute weekly forecasts for COVID-19 cases and deaths reported by a standardised source for 32 countries over the next 1–4 weeks. Teams submitted forecasts from March 2021 using standardised quantiles of the predictive distribution. Each week we created an ensemble forecast, where each predictive quantile was calculated as the equally-weighted average (initially the mean and then from 26th July the median) of all individual models’ predictive quantiles. We measured the performance of each model using the relative Weighted Interval Score (WIS), comparing models’ forecast accuracy relative to all other models. We retrospectively explored alternative methods for ensemble forecasts, including weighted averages based on models’ past predictive performance.Results: Over 52 weeks, we collected forecasts from 48 unique models. We evaluated 29 models’ forecast scores in comparison to the ensemble model. We found a weekly ensemble had a consistently strong performance across countries over time. Across all horizons and locations, the ensemble performed better on relative WIS than 83% of participating models’ forecasts of incident cases (with a total N=886 predictions from 23 unique models), and 91% of participating models’ forecasts of deaths (N=763 predictions from 20 models). Across a 1–4 week time horizon, ensemble performance declined with longer forecast periods when forecasting cases, but remained stable over 4 weeks for incident death forecasts. In every forecast across 32 countries, the ensemble outperformed most contributing models when forecasting either cases or deaths, frequently outperforming all of its individual component models. Among several choices of ensemble methods we found that the most influential and best choice was to use a median average of models instead of using the mean, regardless of methods of weighting component forecast models.Conclusions: Our results support the use of combining forecasts from individual models into an ensemble in order to improve predictive performance across epidemiological targets and populations during infectious disease epidemics. Our findings further suggest that median ensemble methods yield better predictive performance more than ones based on means. Our findings also highlight that forecast consumers should place more weight on incident death forecasts than incident case forecasts at forecast horizons greater than 2 weeks.
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2.
  • Jaworski, G., et al. (författare)
  • The New Neutron Multiplicity Filter NEDA and Its First Physics Campaign with AGATA
  • 2019
  • Ingår i: Acta Physica Polonica B. - 0587-4254 .- 1509-5770. ; 50:3, s. 585-590
  • Tidskriftsartikel (refereegranskat)abstract
    • A new neutron multiplicity filter NEDA, after a decade of design, R&D and construction, was employed in its first physics campaign with the AGATA spectrometer. Properties and performance of the array are discussed.
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3.
  • Valiente-Dobon, J. J., et al. (författare)
  • NEDA-NEutron Detector Array
  • 2019
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 927, s. 81-86
  • Tidskriftsartikel (refereegranskat)abstract
    • The NEutron Detector Array, NEDA, will form the next generation neutron detection system that has been designed to be operated in conjunction with gamma-ray arrays, such as the tracking-array AGATA, to aid nuclear spectroscopy studies. NEDA has been designed to be a versatile device, with high-detection efficiency, excellent neutron-gamma discrimination, and high rate capabilities. It will be employed in physics campaigns in order to maximise the scientific output, making use of the different stable and radioactive ion beams available in Europe. The first implementation of the neutron detector array NEDA with AGATA 1 pi was realised at GANIL. This manuscript reviews the various aspects of NEDA.
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4.
  • Fahlander, Claes, et al. (författare)
  • Excited States in 103Sn: Neutron Single-particle Energies with Respect to 100Sn
  • 2001
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813 .- 1089-490X. ; 63:2
  • Tidskriftsartikel (refereegranskat)abstract
    • Gamma-ray lines from Sn-103 have been identified for the first time using EUROBALL and ancillary detectors. The level scheme of Sn-103 has been established by means of particle-gated gamma gamma coincidences. The energy spacing between the g(7/2) and d(5/2) neutron single-particle orbitals is determined from the excited states in Sn-103.
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5.
  • Gadea, A., et al. (författare)
  • Observation of Ni-54 : Cross-conjugate symmetry in f(7/2) mirror energy differences
  • 2006
  • Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:15, s. 152501-
  • Tidskriftsartikel (refereegranskat)abstract
    • Gamma decays from excited states up to J(pi)=6(+) in the N=Z-2 nucleus Ni-54 have been identified for the first time. Level energies are compared with those of the isobars Co-54 and Fe-54 and of the cross-conjugate nuclei of mass A=42. The good but puzzling f(7/2) cross-conjugate symmetry in mirror and triplet energy differences is analyzed. Shell model calculations reproduce the new data but the necessary nuclear charge-dependent phenomenology is not fully explained by modern nucleon-nucleon potentials.
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6.
  • Palacz, M., et al. (författare)
  • Investigations of Neutron Deficient Nuclei Close to 100Sn with EUROBALL
  • 2001
  • Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254 .- 1509-5770. ; 32, s. 999-1003
  • Tidskriftsartikel (refereegranskat)abstract
    • Excited states of nuclei in the vicinity of Sn-100 have been studied using: the EUROBALL detector array. Gamma-ray lines from Sn-103 have been identified for the first time, and a level scheme of low-lying excited states of Sn-103 has been established. New constraints on energies of single particle orbitals with respect to the Sn-100 core are obtained.
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7.
  • Sohler, D, et al. (författare)
  • Maximally Aligned States in the Proton Drip Line Nucleus 106Sb
  • 2005
  • Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 753:3-4, s. 251-262
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin states in Sb-106 have been investigated in the Fe-54(Ni-58, 1α 1p1n) reaction by in-beam γ-spectroscopic methods using the EUROBALL detector array equipped with charged particle and neutron detectors. On the basis of measured γγ-coincidence relations, angular distributions, and linear polarization ratios a significantly extended level scheme has been constructed up to spin and parity I-π = (19(-)) and E-x ∼ 6.5 MeV. The experimental results are interpreted within the framework of the gdsh shell model using a realistic effective nucleon-nucleon interaction. Candidates for states with fully aligned angular momenta in the π(d(5/2), g(7/2))(1) v (d(5/2), g(7/2))(5) valence space are identified at 4338 and 5203 keV, as well as in the π(d(5/2), g(7/2))(1) V(d(5/2), g(7/2))(4)h(11/2)(1) space at 6087, 6573 and 6783 keV.
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8.
  • Egea Canet, F. J., et al. (författare)
  • A New Front-End High-Resolution Sampling Board for the New-Generation Electronics of EXOGAM2 and NEDA Detectors
  • 2015
  • Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 62:3, s. 1056-1062
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper presents the final design and results of the FADC Mezzanine for the EXOGAM (EXOtic GAMma array spectrometer) and NEDA (Neutron Detector Array) detectors. The measurements performed include those of studying the effective number of bits, the energy resolution using HP-Ge detectors, as well as timing histograms and discrimination performance. Finally, the conclusion shows how a common digitizing device has been integrated in the experimental environment of two very different detectors which combine both low-noise acquisition and fast sampling rates. Not only the integration fulfilled the expected specifications on both systems, but it also showed how a study of synergy between detectors could lead to the reduction of resources and time by applying a common strategy.
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9.
  • Egea Canet, F. J., et al. (författare)
  • Digital Front-End Electronics for the Neutron Detector NEDA
  • 2015
  • Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 62:3, s. 1063-1069
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper presents the design of the NEDA (Neutron Detector Array) electronics, a first attempt to involve the use of digital electronics in large neutron detector arrays. Starting from the front-end modules attached to the PMTs (PhotoMultiplier Tubes) and ending up with the data processing workstations, a comprehensive electronic system capable of dealing with the acquisition and pre-processing of the neutron array is detailed. Among the electronic modules required, we emphasize the front-end analog processing, the digitalization, digital pre-processing and communications firmware, as well as the integration of the GTS (Global Trigger and Synchronization) system, already used successfully in AGATA (Advanced Gamma Tracking Array). The NEDA array will be available for measurements in 2016.
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10.
  • Sohler, D, et al. (författare)
  • Neutron Excitations Across the N=50 Shell Gap in 102In
  • 2002
  • Ingår i: Nuclear Physics, Section A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 708:3-4, s. 181-189
  • Tidskriftsartikel (refereegranskat)abstract
    • The structure of In-102 has been investigated by in-beam gamma-spectroscopic methods. Knowledge on the excited states of this nucleus has significantly been extended. Three cascades of transitions were observed to exceed the spin-energy domain spanned by the pig(9/2)(-1)v(d(5/2),g(7/2))(3) configurations. The new high spin states at similar to 4 MeV excitation energy could be assigned to the pig(9/2)(-1)v(d(5/2), g(7/2))(2)h (11/2) configuration, while at least those at 4.733, 5.192 and 5.853 MeV most likely arise from the vg(9/2) --> vd(5/2), g(7/2) one-particle-one-hole excitation across the N = 50 shell closure.
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11.
  • Palacz, M, et al. (författare)
  • Highly efficient charged particle veto detector CUP
  • 2005
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 550:1-2, s. 414-424
  • Tidskriftsartikel (refereegranskat)abstract
    • A novel, highly efficient, plastic scintillator detector has been constructed. The primary application of the detector is to act as a veto device in heavy-ion-induced fusion-evaporation reactions, in which the structure of proton-rich nuclides is investigated by gamma-ray spectroscopy methods. The detector rejects events in which light charged particles, like protons and alpha particles, are emitted in the evaporation process, facilitating selection of reaction channels associated with emission of only neutrons. The detector was used in a EUROBALL experiment, with achieved efficiencies of 80% and 63% for protons and alpha particles, respectively. The design of the detector, its performance and limitations are discussed.
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12.
  • Pausch, G., et al. (författare)
  • RoSiB - a 4 pi silicon ball for charged-particle detection in EUROBALL
  • 2000
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 443:03-feb, s. 304-318
  • Tidskriftsartikel (refereegranskat)abstract
    • A 4 pi silicon bail for detection and identification of light charged particles in large multidetector gamma-arrays as EUROBALL is presented. The design is based on a N = 42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive material for gamma-rays is minimized to the detector thickness of 300 or 500 mu m and a 0.63 mm ceramic backing. The geometrical coverage is designed for about 90% of 4 pi. A pulse shape discrimination method with totally depleted detectors working in the reverse mount allows identifying protons and alpha-particles above an energy threshold of about 2 MeV. The performances of the ball were rested at the tandem - booster accelerator combination of the MPI Heidelberg in two experiments using the high-recoil reaction of 228 MeV Ni-58 + Ti-46 and the low-recoil reaction of 95 MeV O-16 + Ni-58. The two-dimensional spectra of zero-crossing (ZC) versus energy confirmed an excellent discrimination of protons and alpha-particles in all the detectors at different angles. The energy spectra of protons and alpha-particles measured in the experiments are presented. too. The gamma-spectra measured in coincidence with various combinations of emitted particles showed a high selectivity of the ball. The reduced total efficiency for protons of 59% and 55% and alpha-particles of 44% and 32% measured in a nuclear spectroscopy application is analyzed in a Monte-Carlo simulation (GEANT). It is due to a combined influence of a thick target needed to stop the recoiling residual nuclei and thick absorbers needed to protect the Si-detectors from scattered beam. The results along with the GEANT extrapolation to optimum experimental conditions confirm that RoSiB is a highly efficient and selective device for identification of rare reaction channels with heavy ions.
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13.
  • Perot, B., et al. (författare)
  • Measurement of 14 MeV neutron-induced prompt gamma-ray spectra from 15 elements found in cargo containers
  • 2008
  • Ingår i: Applied Radiation and Isotopes. - : Elsevier BV. - 0969-8043 .- 1872-9800. ; 66:4, s. 421-434
  • Tidskriftsartikel (refereegranskat)abstract
    • Within the EURopean Illicit TRAfficking Countermeasures Kit (EURITRACK) project, the gamma-ray spectra produced in a series of materials by 14-MeV tagged-neutron beams have been collected in the inspection portal equipped with large volume Nal(Tl) detectors, in order to build a database of signatures for various elements: C, N, O, Na, Al, Si, Cl, K, Ca, Cr, Fe, Ni, Cu, Zn, Pb. The measured spectra have been compared with prediction from Monte Carlo simulations to verify the consistency of the relevant nuclear data inputs. This library of measured 14-MeV neutron-induced gamma-ray spectra is currently used in a data processing algorithm to unfold the energy spectra of the transported goods into elementary contributions, thus allowing material identification.
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14.
  • Perot, B., et al. (författare)
  • The EURITRACK project : Development of a tagged neutron inspection system for cargo containers
  • 2006
  • Ingår i: Proc SPIE Int Soc Opt Eng. - : SPIE. - 0819462691 - 9780819462695
  • Konferensbidrag (refereegranskat)abstract
    • The EURopean Illicit TRAfficing Countermeasures Kit project is part of the 6th European Union Framework Program, and aims at developing a neutron inspection system for detecting threat materials (explosives, drugs, etc.) in cargo containers. Neutron interaction in the container produces specific gamma-rays used to determine the chemical composition of the inspected material. An associated particle sealed tube neutron generator is developed to allow precise location of the interaction point by direction and time-of-flight measurements of the neutrons tagged by alpha-particles. The EURITRACK project consists in developing: a transportable deuterium-tritium neutron generator including a position sensitive alpha detector (8×8 matrix of YAP:Ce crystals coupled to a multi-anode photomultiplier), fast neutron and gamma-ray detectors, front-end electronics to perform coincidence and spectroscopic measurements, and an integrated software which manages neutron generator and detectors positioning, data acquisition and analysis. Hardware components have been developed and tested by the consortium partners. Current status of this work and provisional performances of the system assessed by Monte Carlo calculations are presented.
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15.
  • Skeppstedt, O, et al. (författare)
  • The EUROBALL neutron wall - design and performance tests of neutron detectors
  • 1999
  • Ingår i: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV. ; 421:3, s. 531-541
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • The mechanical design of the EUROBALL neutron wall and neutron detectors, and their performance measured with a Cm-246,Cm-248 fission source are described. The array consists of 15 pseudohexaconical detector units subdivided into three, 149 mm high, herme
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16.
  • Viesti, G., et al. (författare)
  • Scanning cargo containers with tagged neutrons
  • 2007
  • Ingår i: 7th Latin American Symposium on Nuclear Physics and Applications. - : American Institute of Physics (AIP). - 0735404615 - 9780735404618 ; , s. 57-62
  • Konferensbidrag (refereegranskat)abstract
    • A new Tagged Neutron Inspection System (TNIS) able to detect illicit materials such as explosives and narcotics in cargo containers has been developed within the EURopean Illicit TRAfficing Countermeasures Kit (EURITRACK) project. After the R&D phase, the inspection portal has been installed and commissioned at the Rijeka seaport in Croatia, where it has been operated in connection with the existing X-ray scanner for a first two-month demonstration campaign. Results obtained are presented and discussed in this paper.
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17.
  • Balcerzyk, M., et al. (författare)
  • Energy resolution and light yield non-proportionality of ZnSe : Te scintillator studied by large area avalanche photodiodes and photomultipliers
  • 2002
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 482:3, s. 720-727
  • Tidskriftsartikel (refereegranskat)abstract
    • The ZnSe: Te scintillator has been studied by means of a photomultiplier with an extended bialkali photocathode, a large area avalanche photodiode (LAAPD) and a PIN photodiode. The light output was determined to be 28 300+/-1700 photons/MeV. Results indicate good proportionality for light output versus gamma-ray energy. Measurements of the 662 keV gamma-ray energy spectrum recorded using a LAAPD resulted in an energy resolution of 5.4+/-0.3%. Based on these results, an intrinsic energy resolution of 3.3+/-0.7% has been calculated.
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18.
  • Moszynski, M., et al. (författare)
  • Energy resolution and non-proportionality of the light yield of pure CsI at liquid nitrogen temperatures
  • 2005
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 537:02-jan, s. 357-362
  • Tidskriftsartikel (refereegranskat)abstract
    • The energy resolution and non-proportionality of the light yield versus gamma-ray energy of pure CsI scintillators directly coupled to Large Area Avalanche Photodiodes (LAAPDs) and cooled down to the liquid nitrogen temperatures have been studied. A very high light output above 100 000 ph/MeV was measured. One of the samples showed nearly proportional light yield response versus energy of gamma-rays yielding energy resolution of 4.3-0.2% for 662 keV gamma-rays from a (CS)-C-137 source. The intrinsic resolution of the crystals versus energy of gamma-rays has been estimated by measurements of the number of primary electron-hole pairs generated in LAAPD by scintillation light. Inspection of the gamma-ray-induced emission spectra of tested samples allows discussing different shapes of non-proportionality curves observed with various samples of CsI.
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19.
  • Moszynski, M., et al. (författare)
  • Study of pure NaI at room and liquid nitrogen temperatures
  • 2003
  • Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 50:4, s. 767-773
  • Tidskriftsartikel (refereegranskat)abstract
    • Three pure NaI crystals grown in different batches by Scionix (The Netherlands) were studied at room and liquid nitrogen temperatures. The room temperature studies performed with photomultiplier readout covered measurements of emission spectra, photoelectrons yield and energy resolution. Moreover, the scintillation light poises were measured by single photon method. Two crystals showed the photoelectron yield of about 1000 phe/MeV measured at room temperature with an XP2020Q photomultiplier. The energy resolution of the 662 keV photopeak was measured to, be about 16% and was limited mainly by a low number of photoelectrons and a large nonproportionality of the light yield. The fast light pulse had the main decay time components of 1 and 5 ns. The high initial photon intensity of the tested NaI crystals revealed a good timing. resolution of about 140 ps obtained for Co-60 gamma-rays. At. liquid nitrogen temperatures the measurements of light yield and energy resolution were performed using An Advanced Photonix, Inc. avalanche photodiode readout A high light output above 80 000 ph/MeV was measured for the best of the tested crystals. The energy resolutions of the 662 kAV photopeak of the three crystals differ a lot, varying from an excellent value of 3.8% to 6.2%. This suggests that the measured, pies energy resolutions depend on the purity of the scintillator samples reflected in the emission spectral The studies that were performed demonstrate the attractive properties of pure NaI at both room and LN2 temperature.
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20.
  • Palacz, M., et al. (författare)
  • N=50 Core Excited States Studied in the 96Pd Nucleus
  • 2012
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813 .- 1089-490X. ; 86:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The four-proton hole Pd-96 neighbor of the doubly-magic Sn-100 nucleus was studied in-beam, using a fusion-evaporation reaction of a Ni-58 beam on a Sc-45 target. States of Pd-96 were established up to an excitation energy of 9707 keV. A core-excited odd-parity isomer with T-1/2 = 37.7(1.1) ns was identified. Shell model calculations were performed in four different model spaces. Even-parity states of Pd-96 are very well reproduced in large-scale shell model (LSSM) calculations in which excitations are allowed of up to five g(9/2) protons and neutrons across the N = Z = 50 gap, to the g(7/2), d(5/2), d(3/2), and s(1/2) orbitals. The odd-parity isomer can be only qualitatively interpreted though, employing calculation in the full fpg shell model space, with just one particle-hole core excitation.
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21.
  • Palacz, M., et al. (författare)
  • Odd-Parity Sn-100 Core Excitations
  • 2013
  • Ingår i: Acta Physica Polonica B. - 0587-4254 .- 1509-5770. ; 44:3, s. 491-500
  • Tidskriftsartikel (refereegranskat)abstract
    • Odd-parity core excited states have been identified in two close neighbors of Sn-100: Pd-96 and Ag-97. This was done in an fusion-evaporation experiment, using a Ni-58 beam on a Sc-45 target. Even-parity core excited states in these nuclei are very well reproduced in large scale (LSSM) calculations in which particle-hole excitations are allowed with up to five g(9/2) protons and neutrons across the N = Z = 50 gap, to the g(7/2), d(5/2), d(3/2), and s(1/2) orbitals. The odd-parity states can only be qualitatively interpreted though, employing calculations in the full fpg shell model space, but with just one particle-hole core excitation allowed. A more complete model including odd-parity orbitals is need for the description of core excited states in the region of Sn-100. 
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22.
  • Pausch, G, et al. (författare)
  • RoSiB - a 4 pi silicon ball for charged-particle detection in EUROBALL
  • 2000
  • Ingår i: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV, AMSTERDAM. - 0168-9002. ; 443:2-3, s. 304-318
  • Tidskriftsartikel (refereegranskat)abstract
    • A 4 pi silicon bail for detection and identification of light charged particles in large multidetector gamma-arrays as EUROBALL is presented. The design is based on a N = 42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive
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23.
  • Borcan, C, et al. (författare)
  • First identification of excited states in the N = Z nucleus Br-70
  • 1999
  • Ingår i: EUROPEAN PHYSICAL JOURNAL A. - : SPRINGER VERLAG. ; 5:3, s. 243-246
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Excited states in the T-z = 0 nucleus Br-70 have been investigated using the reaction Ni-58(O-16,1p3n). gamma rays were detected with one EUROBALL CLUSTER detector and three single HPGe detectors. Charged particles and neutrons were registered with the Ro
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24.
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25.
  • Kapusta, M., et al. (författare)
  • Comparison of the scintillation properties of LSO : Ce manufactured by different laboratories and of LGSO : Ce
  • 2000
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 47:4, s. 1341-1345
  • Tidskriftsartikel (refereegranskat)abstract
    • We measured photoelectron yield, light output, decay times of the light pulses, cerium concentration, energy resolution and time resolution of LSO:Ce manufactured by different laboratories and LGSO:Ce. The LSO samples show excellent scintillation properties: high light output, close to 30,000 ph/MeV and good energy resolution of 7.3% FWHM for Cs-137 gamma-source full energy peak. Time resolution measured in geometry fulfilling the PET scanners requirements is equal to 450 ps. We also present results fi om the measurements with LGSO:Ce by Hitachi Chemical Co., which is of similar chemical composition to LSO. LGSO, at present stage of development, shows about 20% lower light output than LSO and energy resolution of 12.4% FWHM for 662 keV gamma-rays. LSO crystals used in our studies posses similar in scintillation properties, although we suppose that the details of the productions method are different due to the differences in Ce concentration. LGSO is a new and very promising scintillator due to lower background radiation in comparison to LSO, but it features worse energy resolution and smaller number of photoelectrons.
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26.
  • Klamra, Wlodzimierz, et al. (författare)
  • Studies of scintillation light nonproportionality of ZnSe(Te), CsI(Tl) and YAP(Ce) crystals using heavy ions
  • 2002
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 484:03-jan, s. 327-332
  • Tidskriftsartikel (refereegranskat)abstract
    • The scintillation light yield for ZnSe(Te), CsI(T1) and YAP(Ce) crystals have been studied with alpha particles, C-12 and Br-81 in the energy region 2.8-42.2 MeV. A nonproportional behavior was observed, mostly pronounced for alpha particles on YAP(Ce). The results are understood in terms of delta-rays effect.
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27.
  • Luo, X. L., et al. (författare)
  • Pulse pile-up identification and reconstruction for liquid scintillator based neutron detectors
  • 2018
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : ELSEVIER SCIENCE BV. - 0168-9002 .- 1872-9576. ; 897, s. 59-65
  • Tidskriftsartikel (refereegranskat)abstract
    • The issue of pulse pile-up is frequently encountered in nuclear experiments involving high counting rates, which will distort the pulse shapes and the energy spectra. A digital method of off-line processing of pile-up pulses is presented. The pile-up pulses were firstly identified by detecting the downward-going zero-crossings in the first-order derivative of the original signal, and then the constituent pulses were reconstructed based on comparing the pile-up pulse with four models that are generated by combining pairs of neutron and.. standard pulses together with a controllable time interval. The accuracy of this method in resolving the pile-up events was investigated as a function of the time interval between two pulses constituting a pile-up event. The obtained results show that the method is capable of disentangling two pulses with a time interval among them down to 20 ns, as well as classifying them as neutrons or gamma rays. Furthermore, the error of reconstructing pile-up pulses could be kept below 6% when successive peaks were separated by more than 50 ns. By applying the method in a high counting rate of pile-up events measurement of the NEutron Detector Array (NEDA), it was empirically found that this method can reconstruct the pile-up pulses and perform neutron-gamma discrimination quite accurately. It can also significantly correct the distorted pulse height spectrum due to pile-up events.
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28.
  • Luo, X. L., et al. (författare)
  • Test of digital neutron-gamma discrimination with four different photomultiplier tubes for the NEutron Detector Array (NEDA)
  • 2014
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 767, s. 83-91
  • Tidskriftsartikel (refereegranskat)abstract
    • A comparative study of the neutron-gamma discrimination performance of a liquid scintillator detector BC501A coupled to four different 5 in photomultiplier tubes (ET9390kb, R11833-100, XP4512 and R4144) was carried out Both the Charge Comparison method and the Integrated Rise-Time method were implemented digitally to discriminate between neutrons and gamma rays emitted by a Cf-252 source. In both methods, the neutron-gamma discrimination capabilities of the four photomultiplier tubes were quantitatively compared by evaluating their figure-of-merit values at different energy regions between 50 keVee and 1000 keVee. Additionally, the results were further verified qualitatively using time-of-flight to distinguish gamma rays and neutrons. The results consistently show that photomultiplier tubes R11833-100 and ET9390kb generally perform best regarding neutron-gamma discrimination with only slight differences in figure-of-merit values. This superiority can be explained by their relatively higher photoelectron yield, which indicates that a scintillator detector coupled to a photomultiplier tube with higher photoelectron yield tends to result in better neutron-gamma discrimination performance. The results of this work will provide reference for the choice of photomultiplier tubes for future neutron detector arrays like NEDA.
  •  
29.
  • Modamio, V., et al. (författare)
  • Digital pulse-timing technique for the neutron detector array NEDA
  • 2015
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 775, s. 71-76
  • Tidskriftsartikel (refereegranskat)abstract
    • A new digital pulse-timing algorithm, to be used with the future neutron detector array NEDA, has been developed and tested. The time resolution of four 5 in diameter photomultiplier tubes (XP4512, R4144, R11833-100, and ET9390-kb), coupled to a cylindrical 5 in by 5 in BC501A liquict scintillator detector was measured by employing digital sampling electronics and a constant fraction discriminator (CFD) algorithm. The zero crossing of the CM algorithm was obtained with a cubic spline interpolation, which was continuous up to the second derivative. The performance of the algorithm was studied at sampling rates of 500 MS/s and 200 MS/s. The time resolution obtained with the digital electronics was compared to the values acquired with a standard analog CFD. The result of this comparison shows that the time resolution from the analog and the digital measurements at 500 MS/s and at 200 MS/s are within 15% for all the tested photomultiplier tubes.
  •  
30.
  • Moszynski, M., et al. (författare)
  • Application of large area avalanche photodiodes to study scintillators at liquid nitrogen temperatures
  • 2003
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 504:03-jan, s. 307-312
  • Tidskriftsartikel (refereegranskat)abstract
    • Properties of Large Area Avalanche Photodiodes (LAAPDs) at liquid nitrogen (LN2) temperatures in application to study pure NaI, CsI and BGO scintillators are presented. All the tested crystals exhibited excellent performance at LN2 temperatures reflected by a high light output and very good energy resolution. The study showed that the LAAPD operating at LN2 temperatures is an excellent light readout device for testing different scintillators at low temperatures.
  •  
31.
  • Moszynski, M., et al. (författare)
  • Energy resolution and light yield non-proportionality of pure NaI scintillator studied with large area avalanche photodiodes at liquid nitrogen temperatures
  • 2002
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 486:02-jan, s. 13-17
  • Tidskriftsartikel (refereegranskat)abstract
    • The pure NaI crystal has been studied using a Large Area Avalanche Photodiode (LAAPD) at near liquid nitrogen (LN2) temperatures. The study showed a high light output of 44000+/-4000 photons/MeV (ph/MeV), the energy resolution of 5.9 +/- 0.2% for 661.6 keV gamma-rays from a Cs-137 source and a good proportionality of the light yield versus gamma-ray energy. It has been shown also that a cooled LAAPD is an excellent photodetector to study scintillators at near LN2 temperatures.
  •  
32.
  • Moszynski, M., et al. (författare)
  • Intrinsic energy resolution of pure NaI studied with large area avalanche photodiodes at liquid nitrogen temperatures
  • 2003
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 505:02-jan, s. 63-67
  • Tidskriftsartikel (refereegranskat)abstract
    • The energy resolution and non-proportionality of the light yield vs gamma-ray energy of pure NaI scintillators directly coupled to Large Area Avalanche Photodiodes (LAAPDs) and cooled down to the liquid nitrogen temperatures have been studied. Large improvements of energy resolution and nearly proportional light yield response have been obtained at very long shaping time constants. Energy resolution of 3.8+/-0.1% for 662 keV gamma-rays from a Cs-137 source was recorded at 50 mus integration time. The intrinsic resolution of the crystal vs energy of gamma-rays has been estimated by measurements of the number of primary electron-hole pairs generated in LAAPD by scintillation light.
  •  
33.
  • Swiderski, L., et al. (författare)
  • Scintillation response to gamma-rays measured at wide temperature range for Tl doped CsI with SiPM readout
  • 2019
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : ELSEVIER SCIENCE BV. - 0168-9002 .- 1872-9576. ; 916, s. 32-36
  • Tidskriftsartikel (refereegranskat)abstract
    • A custom design cryostat was constructed to study the temperature dependence of relative light yield and non-proportionality trends of scintillators between -182 degrees C and +152 degrees C. CsI:Tl crystal response to gamma-rays and X-rays was investigated between 14 keV and 662 keV. Scintillation light was detected by a SiPM device, which was installed on a copper frame separated from the crystal and the cooling rod to enable operating the device at room temperature. The scintillation efficiency of CsI:Tl is peaked at about room temperature. The light yield of CsI:Tl at temperature close to liquid nitrogen boiling point is reduced by a factor of 15 in comparison to room temperature conditions. The non-proportionality of CsI:Tl scintillation response is high at low temperatures and is getting more proportional with increasing temperature.
  •  
34.
  • Swiderski, L., et al. (författare)
  • Temperature Dependence of CsI:T1 Scintillation Pulse Shapes from-183 degrees C to+90 degrees C Measured with a SiPM Readout
  • 2017
  • Ingår i: 2017 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE (NSS/MIC). - : IEEE. - 9781538622827
  • Konferensbidrag (refereegranskat)abstract
    • A custom designed cryostat was constructed to measure the response of a CsI:T1 scintillator in temperature range from -183 degrees C up to +90 degrees C. The light readout was realized using a SiPM developed by FBK in near ultraviolet high density (NUV-HD) technology. The crystal and the SiPM were installed on separated copper frames. The crystal was cooled down by liquid nitrogen, while the SiPM was kept at temperature close to room temperature. A separation of 1 mm was kept between the crystal and the photodetector to ensure thermal isolation. The temperature of the crystal could be varied by heaters on the scintillator frame and was continuously monitored using a coil shaped resistance thermometer. The CsI:T1 scintillation decay profiles were recorded in the entire temperature range provided by the cryostat.
  •  
35.
  • Swiderski, L., et al. (författare)
  • Temperature Dependence of CsI:Tl Scintillation Pulse Shapes from -183°C to +90°C Measured with a SiPM Readout
  • 2018
  • Ingår i: 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2017 - Conference Proceedings. - : Institute of Electrical and Electronics Engineers Inc.. - 9781538622827
  • Konferensbidrag (refereegranskat)abstract
    • A custom designed cryostat was constructed to measure the response of a CsI:Tl scintillator in temperature range from - 183 ^{circ}\mathrm {C} up to +90 ^{circ}\mathrm {C}. The light readout was realized using a SiPM developed by FBK in near ultraviolet high density (NUV-HD) technology. The crystal and the SiPM were installed on separated copper frames. The crystal was cooled down by liquid nitrogen, while the SiPM was kept at temperature close to room temperature. A separation of 1 mm was kept between the crystal and the photodetector to ensure thermal isolation. The temperature of the crystal could be varied by heaters on the scintillator frame and was continuously monitored using a coil shaped resistance thermometer. The CsI:Tl scintillation decay profiles were recorded in the entire temperature range provided by the cryostat.
  •  
36.
  • Söderström, Pär-Anders, 1980-, et al. (författare)
  • Neutron detection and gamma-ray suppression using artificial neural networks with the liquid scintillators BC-501A and BC-537
  • 2019
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : ELSEVIER SCIENCE BV. - 0168-9002 .- 1872-9576. ; 916, s. 238-245
  • Tidskriftsartikel (refereegranskat)abstract
    • In this work we present a comparison between the two liquid scintillators BC-501A and BC-537 in terms of their performance regarding the pulse-shape discrimination between neutrons and gamma rays. Special emphasis is put on the application of artificial neural networks. The results show a systematically higher gamma-ray rejection ratio for BC-501A compared to BC-537 applying the commonly used charge comparison method. Using the artificial neural network approach the discrimination quality was improved to more than 95% rejection efficiency of gamma rays over the energy range 150 to 1000 keV for both BC-501A and BC-537. However, due to the larger light output of BC-501A compared to BC-537, neutrons could be identified in BC-501A using artificial neural networks down to a recoil proton energy of 800 keV compared to a recoil deuteron energy of 1200 keV for BC-537. We conclude that using artificial neural networks it is possible to obtain the same gamma-ray rejection quality from both BC-501A and BC-537 for neutrons above a low-energy threshold. This threshold is, however, lower for BC-501A, which is important for nuclear structure spectroscopy experiments of rare reaction channels where low-energy interactions dominates.
  •  
37.
  • Gierlik, M., et al. (författare)
  • Comparative study of large NaI(Tl) and BGO scintillators for the EURopean illicit TRAfficking countermeasures kit project
  • 2005
  • Konferensbidrag (refereegranskat)abstract
    • One of the essential requirements of the Tagged Neutron Inspection System, which is the principle of the EURITRACK project, is an efficient and inexpensive gamma ray detector. For this purpose properties of cylindrical 3"×3" and 5"×5" BGO, and 3"×3", two different 5"×5", and a rectangular 5"×5" ×10" NaI(Tl) scintillators were explored. In this communication we report on light yield, energy and time resolution of the investigated crystals at high energies of γ-rays. Additionally, results of Monte Carlo simulations of the crystals' efficiencies are compared to peak-to-total ratios obtained experimentally for various combinations of PMTs and the scintillators.
  •  
38.
  • Gierlik, M., et al. (författare)
  • Comparative study of large NaI(Tl) and BGO scintillators for the EURopean Illicit TRAfficking Countermeasures Kit project
  • 2006
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 53:3, s. 1737-1743
  • Tidskriftsartikel (refereegranskat)abstract
    • The Tagged Neutron Inspection System, which is the principle of the EURITRACK project, requires efficient and inexpensive gamma-ray detectors. For this purpose, properties of 3 x 3 and 5 x 5 cylindrical BGO and NaI(TI) scintillators and of a 5 x 5 x 10 rectangular NaI(TI) scintillator were determined. 14 Light yield, energy and time resolution of the investigated crystals at the energy of few MeVs of gamma-rays are emphasized. Additionally, the crystals efficiencies calculated with Monte Carlo simulations are compared to peak-to-total ratios obtained experimentally for various combinations of PMTs and the scintillators.
  •  
39.
  • Klamra, Wlodzimierz, et al. (författare)
  • Light yield non-proportionality of undoped YAP scintillator
  • 2009
  • Ingår i: Journal of Instrumentation. - : IOP Publishing. - 1748-0221. ; 4
  • Tidskriftsartikel (refereegranskat)abstract
    • Scintillation properties of undoped YAP crystal were studied. The emission spectra show a very intense light component at 360 nm. Analysis of the light pulse shape resulted in five components, four of them, with time constants of 38+/-2 ns, 92+/-3 ns, 7.5+/-0.5 mu s and 24+/-3 mu s, representing high light intensity. The light yield was found to be temperature dependent, N-ph=3090+/-130 ph/MeV at liquid nitrogen temperature and N-ph=1440+/-60 ph/MeV at room temperature. Also the light yield non-proportionality shows temperature dependence and is more pronounced at room temperature.
  •  
40.
  •  
41.
  • Swiderski, L., et al. (författare)
  • Boron-10 loaded BC523A liquid scintillator for neutron detection in the border monitoring
  • 2007
  • Ingår i: 2007 IEEE Nuclear Science Symposium & Medical Imaging Conference. - : IEEE. - 1424409233 - 9781424409235 ; , s. 1389-1395
  • Konferensbidrag (refereegranskat)abstract
    • A BC523A liquid scintillator loaded with boron-10 was tested as a detector for both fast and thermal neutrons. Pulse shape discrimination (PSD) method based on a zero-crossing principle was applied to distinguish between neutron and gamma radiation. High quantum efficiency Photonis XP5500B photomultiplier was used to enhance light detection from the scintillator. This allowed a good registration of the energy spectrum of neutron capture events on boron-10, corresponding to about 60 keVee. The applied PSD method proved to be useful for n/γ discrimination. A good resolving power of the method was achieved even without gating on neutron capture events. A comparison with a standard BC501A liquid scintillator was done to evaluate thermal neutrons detection efficiency in BC523A.
  •  
42.
  • Swiderski, L., et al. (författare)
  • Boron-10 Loaded BC523A Liquid Scintillator for Neutron Detection in the Border Monitoring
  • 2008
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 55:6, s. 3710-3716
  • Tidskriftsartikel (refereegranskat)abstract
    • A BC523A liquid scintillator loaded with boron-10 was tested as a detector for both fast and thermal neutrons. A pulse shape discrimination (PSD) method based on a zero-crossing principle was applied to distinguish between neutron and gamma radiation. High quantum efficiency Photonis XP5500B photomultiplier was used to enhance light detection from the scintillator. This allowed a good registration of the energy spectrum of neutron capture events on boron-10, corresponding to about 60 keV gamma-rays. The applied PSD method proved to be useful for n/gamma discrimination. A good resolving power of the method was achieved even without gating on neutron capture events. A comparison with a standard BC501A liquid scintillator was done to evaluate thermal neutrons detection efficiency in BC523A.
  •  
43.
  • Swiderski, L., et al. (författare)
  • CsI:T1 Scintillation Pulse Shapes Measured with a SiPM Photodetector in a Liquid Nitrogen Cryostat
  • 2016
  • Ingår i: 2016 IEEE NUCLEAR SCIENCE SYMPOSIUM, MEDICAL IMAGING CONFERENCE AND ROOM-TEMPERATURE SEMICONDUCTOR DETECTOR WORKSHOP (NSS/MIC/RTSD). - : IEEE. - 9781509016426
  • Konferensbidrag (refereegranskat)abstract
    • A custom designed cryostat was constructed to measure the response of a CsI:T1 scintillator at temperatures close to the boiling point of liquid nitrogen (LN2). The scintillation light was collected by an HUV-HD SiPM from FBK with 6x6 mm(2) area and 25x25 mu m(2) cell pitch. The crystal size was 5x6x7 mm(3). All surfaces except the one facing the SiPM were covered with Teflon tape to enhance light collection by the photodetector. The performance of the experimental setup was verified at room temperature using analog electronics for signal processing. The crystal was mounted on a copper frame placed inside the LN2 cryostat. Since our goal was to measure the scintillation decay profiles, and the SiPM response at low temperatures becomes substantially slower than that observed at room temperature, the SiPM was mounted on a separate copper frame connected with the outer housing to keep it close to room temperature. The separation between the crystal surface and the SiPM was about 1.5 mm at room temperature, and it became smaller once the setup was cooled down to LN2 temperature, but even so the crystal and the photodetector were still separated. This approach allowed us to analyze scintillation pulse shapes of CsI:T1 at LN2 temperatures. An energy spectrum of 662 keV gamma-rays from a Cs-137 source was also recorded. The light yield of the CsI:T1 sample at LN2 temperature stands at about 6 % divided by 8 % of the value observed at room temperature.
  •  
44.
  • Swiderski, L., et al. (författare)
  • CsLTl scintillation pulse shapes measured with a SiPM photodeteetor in a liquid nitrogen cryostat
  • 2017
  • Ingår i: 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop, NSS/MIC/RTSD 2016. - : Institute of Electrical and Electronics Engineers (IEEE).
  • Konferensbidrag (refereegranskat)abstract
    • A custom designed cryostat was constructed to measure the response of a CsI:Tl scintillator at temperatures close to the boiling point of liquid nitrogen (LN 2 ). The scintillation light was collected by an HUV-HD SiPM from FBK with 6×6 mm 2 area and 25×25 μm 2 cell pitch. The crystal size was 5×6×7 mm 3 . All surfaces except the one facing the SiPM were covered with Teflon tape to enhance light collection by the photodetector. The performance of the experimental setup was verified at room temperature using analog electronics for signal processing. The crystal was mounted on a copper frame placed inside the LN 2 cryostat. Since our goal was to measure the scintillation decay profiles, and the SiPM response at low temperatures becomes substantially slower than that observed at room temperature, the SiPM was mounted on a separate copper frame connected with the outer housing to keep it close to room temperature. The separation between the crystal surface and the SiPM was about 1.5 mm at room temperature, and it became smaller once the setup was cooled down to LN 2 temperature, but even so the crystal and the photodetector were still separated. This approach allowed us to analyze scintillation pulse shapes of CsI:Tl at LN 2 temperatures. An energy spectrum of 662 keV γ-rays from a 137 Cs source was also recorded. The light yield of the CsI:Tl sample at LN 2 temperature stands at about 6 % ÷ 8 % of the value observed at room temperature.
  •  
45.
  • Swiderski, L., et al. (författare)
  • Further Study of Boron-10 Loaded Liquid Scintillators for Detection of Fast and Thermal Neutrons
  • 2010
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 57:1, s. 375-380
  • Tidskriftsartikel (refereegranskat)abstract
    • Boron-10 loaded liquid scintillators were studied in order to improve n/gamma separation. Pulse shape discrimination (PSD) was implemented by means of a zero-crossing (ZC) method to distinguish between gamma-rays and fast/slow neutrons. Significant progress was done for BC523A2 and EJ339A2 scintillators loaded with reduced amount of B-10 (2% and 2.5%, respectively), as compared to the results obtained earlier with BC523A loaded with 4.4% of B-10. The improvement was probably caused by the reduction of B-10 content, as indicated in the reported study. A B-10 loaded scintillator EJ309B5 based on non- flammable liquid was also studied, showing the best separation of thermal neutron capture events from fast neutrons, gamma-rays and noise.
  •  
46.
  • Syntfeld-Kazuch, A., et al. (författare)
  • Non-proportionality and Energy Resolution of CsI(Tl)
  • 2007
  • Ingår i: 2006 IEEE Nuclear Science Symposium Conference Record. - : IEEE. - 1424405610 - 9781424405619 ; , s. 1144-1149
  • Konferensbidrag (refereegranskat)abstract
    • Experimental studies of CsI(Tl) crystals with different amount of Tl activator are presented. Such properties like non-proportionality, energy resolution and number of photoelectrons per 1 MeV-γ were inspected at two different shaping time constants, i.e. 3 and 12 μs. A CsT(Tl) crystal was coupled to the XP5212 PMT with a photocathode blue sensitivity of 12.2μA/lmF. Six GsI(Tl) crystals of different size were tested. Among them three samples were of known Tl concentration which amounted roughly 0.05, 0.1 and 0.25 mol%. The data analysis showed much more proportional character of the crystal response, higher number of photoelectrons/MeV-γ, and what follows better overall energy resolution obtained for 12 μs time constant for all tested samples. Calculated intrinsic resolution improved at longer shaping time constant as well, indicating that for CsI(Tl) crystals more proportional response implies better intrinsic energy resolution of the host crystal. In contrast, intrinsic resolution at low energy region (below about 30 keV) deteriorated for the longer shaping time constant. An α/γ ratio was also measured for each tested CsI(Tl) crystal in order to find any indication to an explanation of the intrinsic resolution deterioration for low energy photons at the 12 μs integration time.
  •  
47.
  • Klamra, Wlodzimierz, et al. (författare)
  • Extensive studies on light yield non-proportional response of undoped CeF3 at room and liquid nitrogen temperatures
  • 2013
  • Ingår i: Journal of Instrumentation. - 1748-0221. ; 8:6, s. P06003-
  • Tidskriftsartikel (refereegranskat)abstract
    • In this paper properties of various undoped CeF3 scintillators were investigated at room and liquid nitrogen (LN2) temperatures. The study was focused on measurements of radioluminescence spectra, decay time, non-proportional response to X-and gamma-rays, energy and intrinsic resolution at different temperature environment. Surprisingly, all the tested pure CeF3 crystals show non-proportional response up to 5.1 MeV gamma ray energy, which is contrary to the typical nonproportionality observed below 100 keV for most of the inorganic scintillators. The investigation of the phenomenon occurring in CeF3 scintillators would be another step to get a better knowledge of the scintillators nature, which still has not been entirely understood.
  •  
48.
  • Klamra, Wlodzimierz, et al. (författare)
  • Light yield nonproportionality of doped CeF3 scintillators
  • 2014
  • Ingår i: Journal of Instrumentation. - 1748-0221. ; 9, s. P07013-
  • Tidskriftsartikel (refereegranskat)abstract
    • In this paper measurements of emission spectra, light output and nonproportional response of CeF3 scintillators doped with Ca, Sr, Ba and Pr were conducted. Results showed degradation of the light output for the doped samples in comparison with an undoped CeF3. For each scintillator the nonproportional response on gamma radiation showed unusual lack of saturation at 100 keV, as observed previously for undoped CeF3 samples.
  •  
49.
  • Klamra, Wlodzimierz, et al. (författare)
  • Properties of CdWO4 and ZnWO4 at Liquid Nitrogen Temperature
  • 2009
  • Ingår i: 2009 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-5. - 9781424439614 ; , s. 1561-1565
  • Konferensbidrag (refereegranskat)abstract
    • Two samples of 10 mm diameter and 10 mm height CdWO4 (CdWO) and ZnWO4 (ZnWO) scintillators were studied at room (RT) and liquid nitrogen (LN2) temperature. At room temperature the crystals were coupled to a Photonis XP3212 photomultiplier. During experiments in liquid nitrogen a Large Area Avalanche Photodiode (LAAPD) was used as a photodetector. Measurements of light output, non-proportionality of the light yield and intrinsic resolution as a function of gamma-ray energies were performed at both temperatures. The non-proportionality for the two crystals, likely CaWO4, reveals temperature dependence, to reach the same values at LN2 temperature. Intrinsic energy resolution for both crystals was also changed at LN2 comparing to the data collected at RT. The intrinsic energy resolution was improved below 100 keV and deteriorated for higher energies.
  •  
50.
  • Klamra, Wlodzimierz, et al. (författare)
  • Properties of CdWO4 and ZnWO4 scintillators at liquid nitrogen temperature
  • 2012
  • Ingår i: Journal of Instrumentation. - 1748-0221. ; 7:3, s. P03011-
  • Tidskriftsartikel (refereegranskat)abstract
    • Two samples of 10 mm diameter and 10 mm height CdWO4 and ZnWO4 scintillators were studied at room and liquid nitrogen temperatures. At room temperature the crystals were coupled to a Photonis XP3212 photomultiplier. During experiments at low temperatures a Large Area Avalanche Photodiode was used as a photodetector. Measurements of light output, c of the light yield and intrinsic resolution as a function of gamma-ray energies were performed at both temperatures. The non-proportionality for the two crystals reveals temperature dependence, showing a more proportional behavior at liquid nitrogen temperature. Intrinsic energy resolution values for both crystals also show temperature dependence.
  •  
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