The next generation of radioactive ion beam facilities, which will give experimental access to many exotic nuclei, are presently being developed. These facilities will make it possible to study very short lived exotic nuclei with extreme values of isospin far from the line of beta stability. Such nuclei will be produced with very low cross sections and to study them, new detector arrays are being developed. At the SPIRAL facility in GANIL a neutron detector array, the Neutron Wall, is located. In this work the Neutron Wall has been characterized regarding neutron detection efficiency and discrimination between neutrons and gamma rays. The possibility to increase the efficiency by increasing the high voltage of the photomultiplier tubes has also been studied. For SPIRAL2 a neutron detector array, NEDA, is being developed. NEDA will operate in a high gamma-ray background environment which puts a high demand on the quality of discrimination between neutrons and gamma rays. To increase the quality of the discrimination methods pulse-shape discrimination techniques utilizing digital electronics have been developed and evaluated regarding bit resolution and sampling frequency of the ADC. The conclusion is that an ADC with a bit resolution of 12 bits and a sampling frequency of 100 MS/s is adequate for pulse-shape discrimination of neutrons and gamma rays for a neutron energy range of 0.3-12 MeV.
Recently, the facilities of radioactive ion beam (RIB) combined with advanced detector systems provide us unique opportunity to probe the exotic properties of the nuclei with unusual neutron-to-proton ratio. In this article, a study of characterization of different types of ultra-fast timing detectors: a special type of gas detector (multi-strip multi-gap resistive plate chamber, MMRPC) ($σ$ $<$100 ps), scintillators array ( viz., $LaBr_3:Ce$) (timing resolution ($σ<$250 ps) are being presented. A brief discussion on usage of these different types of ultra-fast timing detector systems at radio…
Nowadays, the current threat of international terrorism is set to a severe level, demanding worldwide enhanced security. Radioactive materials that could be fashioned into a radiation dispersal device typically emit gamma rays, while fissile materials such as uranium and plutonium emit both neutrons and gamma rays via spontaneous or induced fission. Therefore, the detection and identification of hazardous materials has become increasingly important. We present the results of GEANT4 Monte Carlo simulation of an active neutron interrogation system based on highly segmented neutron/gamma-ray dete…
This paper presents the results of neutron flux measurements at two irradiation facilities of the TRIGA Mark II reactor at ENEA Casaccia Research Center, Italy. The goal of these measurements is to provide a complete characterization of neutron irradiation facilities for accurate and precise dose evaluation in radiation damage tests and, more generally, for all applications that need a good knowledge of neutron flux in terms of intensity, energy spectrum and spatial distribution. The neutron activation technique is used to measure the activation rates of several reactions, chosen so to cover t…
Collinear laser spectroscopy is one of the essential tools for nuclear-structure studies. It allows nuclear electromagnetic properties of ground and isomeric states to be extracted with high experimental precision. Radioactive-beam facilities worldwide strive to introduce such capabilities or to improve existing ones. Here we present the implementation of collinear laser spectroscopy at the ALTO research laboratory, along with data from successful off-line commissioning using sodium beam. The instrumental constituents are discussed with emphasis on simple technical solutions and maximized use …
We present the development of a specialized concrete for neutron shielding at neutron research facilities, based on the addition of hydrogen atoms in the form of polyethylene and also B$_{4}$C for enhancing the neutron capture properties of the concrete. We show information on the mechanical properties of the concrete and the neutronics, in particular it's relevance to modern spallation neutron sources, such as the European Spallation Source (ESS), currently under construction in Lund, Sweden. The new concrete exhibits a 15% lower mass density, a compressible strength of 50% relative to a stan…
The Deep Underground Neutrino Experiment (DUNE) is a leading-edge, international experiment for neutrino science and proton decay studies. This experiment is looking for answers regarding several fundamental questions about the nature of matter and the evolution of the universe: origin of matter, unification of forces, physics of black holes. Two far detector prototypes using two distinct technologies have been developed at CERN. The prototypes are testing and validating the liquid argon time projection chamber technology (LArTPC). In neutrino physics, as well as in any experiment with rare in…
There is currently a big effort put into the operation and construction of world class neutron scattering facilities (SNS and SNS-TS2 in the US, J-PARC in Japan, ESS in Europe, CSS in China, PIK in Russia). On the other hand, there exists a network of smaller neutron scattering facilities which play a key role in creating a large neutron scattering community who is able to efficiently use the existing facilities. With the foreseen closure of the ageing nuclear research reactors, especially in Europe there is a risk of seeing a shrinking of the community who would then be able to use efficientl…
We introduce a novel thick-target concept tailored to the extraction of refractory 4d and 5d transition metal radionuclides of molybdenum, technetium, ruthenium and tungsten for radioactive ion beam production. Despite the more than 60-year old history of thick-target ISOL mass-separation facilities like ISOLDE, the extraction of the most refractory elements as radioactive ion beam has so far not been successful. In ordinary thick ISOL targets, their radioisotopes produced in the target are stopped within the condensed target material and have to diffuse through a solid material. Here, we pres…
Uranium fission chambers are commonly used for neutron beam monitoring in neutron research facilities. The challenges brought with the renewing or commissioning of new neutron facilities encourage to minimize the interaction between the monitor and the neutron beam. In order to characterize both their detection efficiency and transmission factor, several fission chambers, have been scanned on the CT1 monochromatic beam line of the ILL. Results show that the monitor transparency, measured at the center of the monitor, varies from 90% to 96%, and that the detection efficiency varies by as much a…
Direct Neutron Reactions in Storage Rings Utilizing a Supercompact Cyclotron Neutron Target
Instituto de Física Corpuscular (CSIC-Universitat de València)（粒子物理与核物理研究所（西班牙国家研究委员会-瓦伦西亚大学））；TRIUMF（特里厄姆夫实验室）；Department of Physics and Astronomy, University of Victoria（维多利亚大学物理与天文学系）；GSI Helmholtzzentrum für Schwerionenforschung GmbH（德国重离子研究中心）；Institut für Kernphysik, Universität zu Köln（科隆大学核物理研究所）
We present a detailed study on detector response to different radioactive sources and the measurements of non-reactor environmental backgrounds with the Indian Scintillator Matrix for Reactor Anti-Neutrinos (ISMRAN) detector setup consisting of 9$\times$10 Plastic Scintillator Bars (PSBs) array at BARC, Mumbai. These measurements are useful in the context of the ISMRAN detector setup, which will be used to detect the reactor anti-neutrinos (${\bar{\ensuremathν}}_{e}$) and measure its energy spectra, through the inverse beta decay (IBD) process. A GEANT4 based Monte Carlo (MC) simulation is use…
A new beamline for Resonant Excitation of Beams with Electromagnetic fields and Lasers (REBEL) and Stopping and Trapping of Radioactive Isotopes for Precision Experiments (STRIPE)
Detection of neutrons is becoming of the utmost importance, especially in the studies of radioactive waste and in homeland security applications. The crisis of 3He availability has required the development of innovative techniques. One solution is to develop light gas detectors for neutron counting to be used as portals for ports and airports. The neutron is converted on the Boron-coated cathode, releasing a charged particle, whose passage can be identified by the gas detector. While several technologies have been deployed in the past, the project μRANIA-V ( μRwell Advanced Neutron Identificat…
A novel experiment has been commissioned at the Weizmann Institute of Science for the study of weak interactions via a high-precision measurement of the beta-neutrino angular correlation in the radioactive decay of short-lived $^{6}$He. The facility consists of a 14 MeV $d+t$ neutron generator to produce atomic $^{6}$He, followed by ionization and bunching in an electron beam ion source, and injection into an electrostatic ion beam trap. This ion trap has been designed for efficient detection of the decay products from trapped light ions. The storage time in the trap for different stable ions …
The production of radioactive isotopes by interactions of cosmic-ray particles with sodium iodide (NaI) crystals can produce radioactive backgrounds in detectors used to search for rare events. Through controlled irradiation of NaI crystals with a neutron beam that matches the cosmic-ray neutron spectrum, followed by direct counting and fitting the resulting spectrum across a broad range of energies, we determined the integrated production rate of several long-lived radioisotopes. The measurements were then extrapolated to determine the sea-level cosmogenic neutron activation rate, including t…
Ions with similar charge-to-mass ratios cannot be separated from existing beam profile monitors (BPMs) in nuclear facilities in which low-energy radioactive ions are produced due to nuclear fusion reactions. In this study, we developed a BPM using a microchannel plate and a charge-coupled device to differentiate the beam profiles of alpha-decaying radioactive isotopes from other ions (reaction products) produced in a nuclear reaction. This BPM was employed to optimize the low-energy radioactive francium ion (Fr+) beam developed at the Cyclotron and Radioisotope Center (CYRIC), Tohoku Universit…
Gamma Neutron Radioactive Source Identification in Water Cherenkov Detectors
Departamento de Física de Neutrones, Centro Atómico Bariloche（中子物理系，巴拉德奥切原子能中心）；Instituto Balseiro, CNEA-UNCuyo（巴尔塞罗研究所，CNEA-门多萨国立大学）；Escuela de Física, Universidad Industrial de Santander（桑坦德工业大学生物物理学院）；Departamento de Ciencias Básicas, Universidad Autónoma de Bucaramanga（巴兰基亚自治大学基础科学系）；Fractalis Adventures & piensas.xyz（Fractalis探险与piensas.xyz）；Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)（国家科学研究委员会）
The concept of the LAr TPC technology that is an excellent tracking - calorimeter detector will be used for the next generations of neutrino experiments. In this class of detectors both the scintillation light emitted and the charge produced by the ionization are used to detect and identify the characteristics of the primary particle. The reduction of the radioactive background, the knowledge of the sources and mechanisms of its production as well as the characteristics of the signals have as consequence the increase of the sensitivity of huge detectors and the capability to discriminate betwe…
Over the last decades, the field of thermal neutron detection has overwhelmingly employed He-3-based technologies. The He-3 crisis together with the forthcoming establishment of the European Spallation Source have necessitated the development of new technologies for neutron detection. Today, several promising He-3-free candidates are under detailed study and need to be validated. This validation process is in general long and expensive. The study of detector prototypes using neutron-emitting radioactive sources is a cost-effective solution, especially for preliminary investigations. That said,…
Extending the applicability of an open-ring trap to perform experiments with a single laser-cooled ion
首先建立了一个开环离子阱，也被称为透明阱，用于进行放射性离子的$β$ - $ν$相关实验。这种陷阱几何形状也非常适合使用激光冷却离子进行实验，有助于在格拉纳达大学TRAPSENSOR项目框架内开发新型彭宁陷阱。本项目的目标是使用单个$^{40}$ Ca $^+$离子作为单离子质谱的检测器。在该项目中，在不对初始电极配置进行任何修改的情况下，可以对$^{40}$ Ca $^+$离子进行多普勒冷却，从大云开始并达到单离子灵敏度。这个新的功能的陷阱可能是重要的，也为其他实验中产生的离子在放射性离子束（RIB）设施。在该出版物中，将描述阱和激光系统，以及它们相对于应用于大离子云直到单个离子的激光冷却的性能。
We have developed a neutron imaging sensor based on an INTPIX4-SOI pixelated silicon device. Neutron irradiation tests are performed at several neutron facilities to investigate sensor's responses for neutrons. Detection efficiency is measured to be around $1.5$\% for thermal neutrons. Upper bound of spatial resolution is evaluated to be $4.1 \pm 0.2 ~μ$m in terms of a standard deviation of the line spread function.
In this paper we present a method for obtention of neutron images with Commercial-Off-The-Shelf (COTS) CMOS image sensors through the activation of indium foils. This detection method has been designed specifically for the acquisition of thermal and epitermal neutron images in mixed beams with a high gamma flux, and also for the study of high radioactive samples that are usually placed into research reactor pools. We also present a technique to obtain multi-spectral neutron images taking advantage of the high neutron absorption cross-section of this material in the thermal energy range, as wel…
