===== Neutron 2024 =====
{{:projects:logo.png?200|}}
----
==== Program ====
10:00 - Zdeněk Matěj - MU (Pecák, Labuda, Hlavinka, Bleha, Szoktowski, Král)\\
10:30 - VF (Jančář, Čulen, Večeřák)\\
10:45 - UPT (Mikel, Jelínek, Zbožínek)\\
11:00 - VUT (Kubíček, Horna, Kolář)\\
11:15 - 11:30 - coffe break\\
11:30 - UNOB (Jánský, Janda) \\
11:45 - VŠB (Alexa)\\
12:00 - CVŘ (Košťál, Czakoj, Zmeškal, Losa)\\
12:30 - 13:30 - lunch\\
13:30 - MIT Boston (Forget)\\
14:00 - IAEA (Roberto Capote)\\
14:30 - Tu Dresden (Viebach)\\
14:45 - 16:30 - Coffe break + discussions...\\
==== Abstrakts ====
**Oldřich Pecák\\
Evaluation of FPGAs for nuclear particle transport simulators **\\
FPGAs provide a different computation model compared to CPUs and GPUs. In this short presentation, we discuss this model and its possible use in nuclear particle simulators like MCNP or OpenMC.
We then look at preliminary benchmark data using XSBench.
**Ján Labuda\\
Neutron-Gamma Analysis Software**\\
The presentation shows some future options made by the new version of the NGA
(neutron and gamma analysis) software, which should ease up its usage for the
experiments and a brief idea of the future usage will be shown, with some
abstract plan of the possible architecture.
** Vojtěch Szotkowski\\
Voltage Dividers for PMT**\\
This presentation will focus on the high-voltage distribution for the
photomultiplier tubes. Firstly, the basic principle of PMT will be explained.
Then, the different voltage divider configurations and their purposes will be
shown. Lastly, the current state of my work and the difficulties I experienced
during the PCB design will be presented.
**Matyáš Hlavinka\\
SVM classification in FPGA**\\
Building on the trailing edge gamma/neutron classification, this project aims
to use a support vector machine to enhance the accuracy of the discrimination.
The trained decision function is implemented and pipelined in a FPGA.
**Ondřej Bleha\\
Remote access for measuring equipment**\\
This short presentation focuses on how to securely connect to measuring equipment over LTE. I will show some hardware, network infrastructure and discuss how it's implemented.
** Aleš Jančář\\
Dosimetry of mixed fields of photons and neutrons**\\
In this post, you will be introduced to the meters for the characterization of mixed fields of photons and neutrons, which I jointly developed with FI and VUT Brno as part of subsidy projects. Next, we will introduce you to the secondary neutron irradiation room that we, as VF NUCLEAR, developed, manufactured and installed at PSI Zurich, Switzerland. The previously mentioned gauges were used to characterize the fields from the installed Am-Be sources.
** Břetislav Mikel\\
Ionizing radiation measurement with optical fibres**\\
We present research in gamma radiation measurements, where we try to use the properties of optical fibres for maximum separation of the detection and measurement part. This is mainly due to the focus on long-term continuous operation of high-activity radiation measurements. We present a state-of-the-art measurement system that can monitor ionising radiation with activities from tens of kBq to tens of TBq. We are currently extending our research into the area of the spectral resolution of radiation sources, where the use of optical fibres is a considerable challenge.
**Aleš Horna\\
Proportional counters**\\
Our efforts are directed towards the characterisation of various available proportional counters and processing of signals they produce. Factory-made as well as experimental counters are tested. The gaseous filling consists of hydrogen (H-1) and/or helium-3 (He-3). The output pulses are amplified by charge-sensitive preamplifiers. The counters are intended for the detection of neutrons, however they also show certain sensitivity to gamma radiation. The discrimination in between these two types is based on different values of the preamplifier output signal rise time. The applicability of this method is to be verified by exposing the counters to gamma and/or neutron fields created by appropriate radioactive sources. The output pulses are recorded by our own acquisition unit sending raw data (waveforms) into a computer and further processed with the use of MATLAB. The aim is to use hydrogen filled counters as a spectrometric detectors of neutron fluxes having the energy in hundred keV range.
**Jiří Janda\\
The influence of oxygen on pulse shape discrimination at various solvents and phosphors**\\
The issue of oxygen quenching on the PSD ability/quality of liquid scintillation cocktails is addressed throughout the investigation of the effect of different solvents on PSD quality and light yield using different concentrations of the phosphor PPO+MSB. Two different atmospheric conditions were in the preparation of the samples, one consisted of air at standard temperature and pressure (STP) and the other was nitrogen. The second part of the work is focused on the influence of the phosphors on the PSD quality and light yield. The effect of only one phosphor with a large Stokes shift was investigated, as well as the effect of a secondary phosphor as a wavelength shifter within the used solvents, again prepared under a nitrogen atmosphere and ambient environment. The used solvents can be divided into three categories: a) classical (toluene, xylene, styrene), b) naphthalene derivates (Diisopropylnaphthalene (mixture of isomers), and 1-Methylnaphthalene) and c) Linear alkylbenzenes (Diethylbenzene, Dodecylbenzene, and Propylbenzene). Five phosphor groups were tested using different phosphors or mixtures of phosphors namely para terphenyl and 1,4-bis(5-phenyloxazol-2-yl) benzene (pTP+POPOP), 2,5-Diphenyloxazole and p-Bis(o-methylstyryl) benzene (PPO+MSB), 1-Phenyl-3-(2,4,6-trimethyl-phenyl)-2-pyrazoline (PYR), 2,5-Bis(5-tert-butyl-benzoxazol-2-yl)thiophene (THIO), and 2-(1-naftyl)-5-fenyloxazol (NPO). The first one is the oldest one with very good PSD ability, the second one is standard in PSD scintillators. The rest of them are experimental phosphores with large Stokes shifts without the need for a second phosphor (wavelength shifter).
**Jaroslav Jánský\\
Measurement of scintillator response to neutrons from cyclotron in the range up to 35 MeV **\\
At the cyclotron in Řež, we measured the responses of scintillators to neutrons with energies of 15.6, 19.69, 25.44, 30.175 and 35.7 MeV. We used three one-inch scintillators: crystalline stilbene, liquid PYR, and liquid THIO. The measurement was performed with the NGA-01 pulse analyzer, which is capable of discriminating neutrons and gamma rays. It was necessary to use minimal currents in the cyclotron source in order for our analyzer to be able to make good resolution. In the end, the measurement was successful that we managed to get the responses. From the responses, we evaluated points in the light yield curve for liquid scintillators PYR and THIO for energies above 20 MeV. From the response for the Stilben scintillator for neutrons with an energy of 30 MeV and below, we calculated a neutron spectrum using the NGA-01 internal unfolding routines, which agreed very well with the expected spectrum of neutrons from the cyclotron.
**Petr Alexa\\
Neutrons in Ostrava: 2012 - 2024**\\
We present a brief history of the neutron laboratory in Ostrava from the very beginning in 2012. Our research is focused on delayed and prompt neutron activation analysis for determination of bulk elemental composition of various samples, e.g. nanostructured magnetite-ceria-based composites, Heusler alloys, explosives and other illicit materials or hydrogen-rich materials. Neutron flux monitoring, tests of different techniques and detectors and dosimetrical cross sections measurements represent another research direction. In particular, we will mention the Texas convention method, stilbene scintillation spectrometers, NEUTRAK dosimeters and Timepix2 and Timepix3 detectors used for fast and thermal neutron discrimination, online monitoring and time-of-flight measurements.\\
This work is supported by SGS SP 2023/036 and SP 2024/016 projects financed by the Ministry of Education, Youth and Sports of the Czech Republic.
**Michal Košťál\\
Broomstick experiment at VR-1 reactor**\\
A deep neutron penetration experiments to study the particle transport in the thick layers of material are essential integral experiments from the point of view of nuclear data validation. The work described within manuscript refers to experimental effort to validate the deep transport through layers of copper. The methodology used for our experiment was firstly introduced by in ORNL in 1967 for oxygen, nitrogen, lead and carbon, when the samples were in pinhole-type geometry using the Tower Shielding Reactor II to maximize the non-collided neutron transmission.
**Tomáš Czakoj\\
Measurement of gamma field inside the biological concrete shielding of VVER-1000 Mock-Up**\\
The long-term operation of nuclear power reactors is a crucial concern due to the complexities and expenses associated with replacing key components, such as the reactor pressure vessel and reactor internals. Gamma radiation, a byproduct of nuclear reactions and radioactive decay, significantly influences the lifetime of these components. This radiation is responsible for various degradation pathways leading to void swelling in steel reactor components and cracking or other radiation damage in concrete structures. A study conducted at a full-scale mock-up of the VVER-1000 reactor at the LR-0 zero-power reactor employed HPGe and stilbene measurements to analyze gamma spectra behind the reactor pressure vessel and within concrete biological shielding.
**Marek Zmeškal\\
Measurement of spectrum and the total yield of secondary neutrons during production of 18F with 18O(p,n)18F reaction**\\
Positron emission tomography is widely spreading diagnostic technique, which needs production of radioisotopes for its use. The most used radiopharmaceutical utilizes 18F. It is produced by irradiation of enriched water with protons of 18 MeV. This production is also strong source of secondary neutrons, which are important for shielding but they could be also further used. A detailed description of the neutron source term is needed. The secondary neutron spectrum at different angles and also absolute yield of neutrons were measured at a special small target designed for this purpose at cyclotron U-120M.
**Evžen Losa\\
Project CHRONIC**\\
Nickel-chromium alloys gain importance in the technology of the accident-tolerant fuel design. Despite their applications in the stainless steel as a part of heavy reflector, they are usually not massively used in the cladding material of classical LWR reactors and therefore it is worth to study their impact on reactivity. Presentation will introduce findings from calculation and experimental studies at the VR-1 reactor focused on highly alloyed materials used as a dummies for Ni-Cr alloys.
**Gavin Ridley**\\
Unresolved resonance (URR) data for neutron transport calculations already stand as a major computational bottleneck in GPU-based Monte Carlo simulations due to the irregular memory access pattern presented by sampling from probability tables. With more highly resolved URR on the horizon for ENDF/BVIII.1, we propose a fresh look at simulating neutron transport in the URR region. Beyond the mathematically serendipity of our new approach, our new methods enable a 20x reduction in data requirements for representing unresolved resonances, maintain a GPU-friendly memory access pattern, and enable higher fidelity temperature dependence compared to conventional methods.
**Roberto Capote at al.\\
INDEN evaluation of copper isotopes **\\
New evaluation of neutron induced reactions on copper isotopes for neutron energies up to 20 MeV is discussed. The important role played by Cf-252(sf) neutron leakage experiments is highlighted. Changes in evaluated reaction data are reviewed and the latest integral performance is shown. This work is the basis of candidate copper evaluations submitted to ENDF/B-VIII.1 and JEFF-4 libraries.
**Marco Viebach\\
Current research at AKR-2**\\
The research and training reactor ARK-2 at TU Dresden, Germany, is a homogeneous, solid-matter moderated zero-power reactor. Besides the training of local and international students and professionals or the demonstration of the technology to the public, the AKR-2 offers a variety of experiments and applications and is involved in multiple research projects. A current major goal is the measurement of the AKR-2 neutron spectrum using activation analyses, neutron time-of-flight, and proton recoil detectors (proportional counters and scintillators) as needed for the determination of nuclear data with the pile oscillator and neutron transmission setups.
==== History ====
[[projects:neutron-2023|Neutron 2023]]