Gas Electron Multipliers (GEM) are widely used as amplification stages in gaseous detectors exposed to high rates. The GEM consists of a polyimide foil which is coated by two thin copper layers. Charges collected into the holes or created during the amplification process may adhere to the polyimide part inside the holes. This is often accompanied by a change of the effective gain. The effect is commonly

High-pressure xenon (HPXe) ionization chamber is a high-energy-resolution radiation detector for gamma spectrometry with excellent physical properties. It has a wide range of operation temperatures, excellent radiation resistance, and long-life performance. Energy resolution is an important parameter of an HPXe gamma-ray spectrometer and has been investigated by scientists through experimental methods

The response of LaBr3(Ce) and LaCl3(Ce) scintillators to fast neutrons is investigated. Neutron-induced charged-particle reactions are observed in both materials when exposed to the fast neutrons produced by an AmBe source, with pulse-shape discrimination used to separate channels. LaBr3(Ce) is found to have the best separation between reaction channels, while LaCl3(Ce) has a significantly higher efficiency

The nuclear half-life of 235mU (the first metastable nuclear excited state of 235U) varies depending on chemical environments because the nucleus interacts only with outer-shell electrons in the nuclear internal conversion (IC) process due to its extremely low excitation energy at 76.737 ± 0.018 eV. Elucidating the mechanism of the half-life variation of this unique isomer would largely contribute

Latent image stability is one of the most important characteristics of nuclear emulsions for cosmic-ray imaging. The emulsions studied are composed of AgBrI grains (about 200 nm in diameter) with a benzothiazolium compound (Additive Ⅰ) as a new latent-image stabilizer, and characterized by means of photoelectron yield spectroscopy in air (PYSA). The results thus observed are discussed in the light

The interest in using the radiation detectors based on high resistive chromium-compensated GaAs (GaAs:Cr) in high energy physics and others applied fields has been growing steadily due to its numerous advantages over others classical materials. High radiation hardness at room temperature stands out and needs to be systematically investigated. In this paper an experimental study of the effect of 20

In this investigation, we have carried out the simulations of light output and the directionality of emission from scintillators coated with microlens arrays by using the ray-optics method. We systematically analyze the impact of an individual microlens at different positions on the light output intensity and the directional control, followed by an entire understanding of microlens arrays. It is found

Radiation damage of J-series silicon photomultipliers (SiPMs) has been studied in the context of using these photodetectors in future space-borne scintillation detectors. Several SiPM samples were exposed to 101.4 MeV protons, with 1 MeV neutron equivalent fluence ranging from 1.27×108 neq/cm2 to 1.23×1010 neq/cm2. After the irradiation, the SiPMs experienced a large increase in the dark current and

Nowadays more and more positron emission tomography (PET) detectors are constructed with a LYSO crystal array coupled to a silicon photomultiplier (SiPM) array. Due to the non-linearity of readout electronics and SiPM response, the energy calibration is needed to obtain the correct 511 keV photopeak position, energy resolution and precise γ photon interaction position. Different with conventional energy

A general-purpose digital data acquisition system (GDDAQ) has been developed at Peking University. This GDDAQ, composed of 16-channel Digital Pulse Processor Pixie-16 modules from XIA LLC, is a versatile, flexible, and easily expandable data acquisition system for nuclear physics research in China. The software used by this GDDAQ is based on the CERN ROOT framework and developed and tested in CentOS

A pulse stretcher providing a 5.2 keV quasi-continuous beam has been developed for use with a pulsed slow-positron beam generated by an electron linear accelerator operated with a repetition frequency of 50 Hz. Pulses of positrons, of width 1.2 µs, were trapped in a Penning–Malmberg trap and then gradually released downstream, stretching the pulse width to nearly 20 ms.

Experiments to measure the electric and the magnetic moments of short-lived baryons using an internal target and two bent crystals in the vicinity of one of the existing LHC detectors were recently proposed, in the frame of the Physics Beyond Colliders Working Group at CERN. Investigating fixed-target physics in the LHC with in-vacuum solid targets is an unprecedented challenge. As a preparatory step

A Geant4 simulation has been carried out in order to determine the β-detection efficiency of a rare isotope beam implantation setup, for decay spectroscopy experiments, comprising a number of Double Sided Silicon Strip Detectors (DSSSDs) and two plastic scintillation detectors placed upstream and downstream. The absolute efficiency for the emitted β-particle detection from radioactive fragments implanted

Pulse shape discrimination, to distinguish between neutrons and gamma rays, is a very important classification task in thermonuclear fusion. Gaussian Mixture Models and probabilistic Support Vector Machines have been applied to hundreds of thousands of pulses obtained with a counter based on the NE213 liquid scintillator. The results of the two completely independent mathematical methods are in very

Single Crystal Diamond (sCD) are candidate neutron detectors for the ITER Radial Neutron Camera (RNC) due to their capability of performing both neutron counting and spectroscopy while withstanding high levels of radiation. This paper presents a study on methods of separation between neutron and gamma events, through the analysis of the pulse shapes of a 500μm thick sCD. Methods for gamma rejection

One of the factors that can contribute to the resolution of long, doped inorganic scintillators used for nuclear spectroscopy is the variation of the dopant concentration over the length the detector crystal. In this work an investigation of such potential variations in one of the CsI(Tl) scintillators used in the calorimeter, CALIFA, of the R3B experiment at FAIR, has been performed using particle

Fast timing detectors are an essential element in the experimental setup for time-of-flight (ToF) mass measurements of unstable nuclei. We have upgraded the scintillator detectors used in experiments at the National Superconducting Cyclotron Laboratory (NSCL) by increasing the number of photomultiplier tubes that read out their light signals to four per detector, and characterized them in a test experiment

CSES (China Seismo-Electromagnetic Satellite) is a Chinese-Italian space mission dedicated to monitoring of variations of the electromagnetic field and waves, plasma parameters, and particle fluxes induced by natural sources and artificial emitters in the near-Earth space. The satellite was launched from the Jiuquan Satellite Launch Center in the Gobi desert (Inner Mongolia, China) on 2, 2018. The

Reflectance of silicon photomultipliers (SiPMs) is an important aspect to understand large scale SiPM-based detector systems and evaluate the performance of SiPMs. We design and produce a new experimental setup to measure the reflectance in air or in a liquid at visible wavelengths for various samples. With the new setup, we establish the measurement methods and validate its measurement results. The

This paper describes the first performance tests and characterization of the detection chain of the Micro-channel X-ray Telescope (MXT), one of the instruments on board the French-Chinese mission SVOM for the study of Gamma-Ray Bursts. The MXT detector consists of a back-illuminated 450µm-thick fully-depleted frame-store silicon pnCCD, operating in the 0.2−10keV energy range. Featuring an imaging area

The growing interest in clarifying the controversial situation in the Dark Matter sector has driven the experimental efforts towards new ways to investigate the long-standing DAMA/LIBRA result. Among them, low-temperature calorimeters based on Na-containing scintillating crystals offer the possibility to clarify the nature of the measured signal via particle identification. Here we report the first

The GBAR experiment is designed to measure the free fall acceleration of antihydrogen atoms almost at rest. We have developed a time-of-flight (TOF) detector for the measurement of free fall time and annihilation position of antihydrogen atoms as well as for the rejection of cosmic ray muons. A scintillator array as a part of the TOF detector was installed and tested at the GBAR experimental hall.

Effects producing gain dilution in FreeElectron Laser devices are well documented. We develop here a unified point of view allowing the introduction of space charge effects, along with the gain deterioration due to inhomogeneous broadening contributions and discuss the relevant interplay. We outline future developments and comment on the possibility of including in the formalism effects of quantum

Pseudo-random number generators are the heart of Monte Carlo simulations. Generally, the quality of random number generators may affect the output of the simulation. Any GEANT4-based Monte Carlo tool has different random number generators. The GATE toolkit, a widely used package in nuclear medicine, also provides three generators for the users to select. In this study, we used the random number generators

The aim of the present study is to fabricate an economical, easily workable and environmentally friendly X-ray and gamma ray-shielding composites using a coating method. Nano- and micron-size powders of WO3, PbO and Bi2O3 were used as a substitution base for the shielding materials. After the synthesis of those materials, they were coated on fabric samples which were then exposed to an X-ray tube at

In this work we propose a method for the determination of the impact point of muons in scintillators using a novel type of self-organizative maps called Self-Equalizing Map (SEM) and comparing the relative pulse height obtained by four photomultipliers (PMTs) at each scintillator. Using two 1 m2 scintillators and calculating the impact point in both of them, we can also estimate the angle of incidence

The beam injection system of the Relativistic Heavy Ion Collider (RHIC) is the last section of the beam transfer line which transports the beam from the Alternating Gradient Synchrotron (AGS) to RHIC and comes under the acronym AtR (AGS to RHIC) (https://ieeexplore.ieee.org/document/749599, https://ieeexplore.ieee.org/abstract/document/749594). The Lambertson septum magnet is one of the magnetic elements

We report on the design, deployment, and first results from a scintillation detector deployed at the Murchison Radio-astronomy Observatory (MRO). The detector is a prototype for a larger array – the Square Kilometre Array Particle Array (SKAPA) – planned to allow the radio-detection of cosmic rays with the Murchison Widefield Array and the low-frequency component of the Square Kilometre Array. The

The time-of-flight (TOF) of an associated white neutron beam line exploiting back-streaming neutrons (Back-n) at China Spallation Neutron Source (CSNS) was obtained using a scintillator detector consisting of stilbene crystal, a photomultiplier tube (PMT), a screening can, and a high sampling rate oscilloscope. An original energy-count spectrum was acquired based on the time-of-flight method. Four

A laser calibration system was developed for monitoring and calibrating time of flight (TOF) scintillating detector arrays. The system includes setups for both small- and large-scale scintillator arrays. Following test-bench characterization, the laser system was recently commissioned in experimental Hall B at the Thomas Jefferson National Accelerator Facility for use on the new Backward Angle Neutron

Silicon neutron detectors can operate at low voltage and come with ease of fabrication and the possibility of integration of readout electronics and thus are attractive from an application point of view. In this paper, we have studied thermal neutron capture by silicon diodes coated with boron carbide (B4C). One of the surfaces of the diodes was covered with either natural B4C (natB4C) or with enriched

The Alpha Magnetic Spectrometer (AMS) is a high energy particle detector aboard the International Space Station. AMS precisely measures the fluxes of all cosmic-ray nuclei with charge from Z=1 to Z=28 and beyond. The AMS silicon tracker measures energy deposition of charged particles traversing over nine-layer silicon sensors, from L1 to L9. In this paper, the details of the AMS silicon tracker charge

The Back-n white neutron source at the China Spallation Neutron Source (CSNS) was put into operation in 2018, providing a good platform for the cross-section measurement of neutron induced light charged particle (lcp) emission (n,lcp) reactions. Currently, in order to detect and identify light charged particles produced in (n,lcp) reactions at Back-n, a silicon detector array has been developed as

The high-luminosity phase of the Large Hadron Collider (HL-LHC) will result in ten times higher particle background than measured during the first phase of LHC operation. In order to fully exploit the highly-demanding operating conditions during HL-LHC, the Compact Muon Solenoid (CMS) Collaboration will use Gas Electron Multiplier (GEM) detector technology. The technology will be integrated into the

Neutrons can induce background events in underground experiments looking for rare processes. Neutrons in a MeV range are produced in radioactive decays via spontaneous fission and (α,n) reactions, and by cosmic rays. Neutron fluxes from radioactivity dominate at large depths (>1 km w. e.). A number of computer codes are available to calculate cross-sections of (α,n) reactions, excitation functions

Solid-state (SS) amplifiers present many benefits and advantages that make this technology a good candidate to substitute traditional vacuum technology amplifiers. The evidence is that many large scientific facilities are upgrading their radiofrequency (RF) power systems, replacing tetrodes or IOTs (Inductive Output Tubes) by SS amplifiers. Following this tendency, SS technology has been selected for

The Belle II experiment at the SuperKEKB collider of KEK (Japan) started recording physics data in spring 2019 with all its subdetectors installed and with the goal of accumulating 50 ab−1 of e+e− collision events at the unprecedented instantaneous luminosity of 8×1035cm−2s−1, about 40 times larger than its predecessor. The Belle II vertex detector plays a crucial role in the broad Belle II physics

Passive CMOS pixel sensors in 150 nm CMOS technology offered by LFoundry were designed and assembled into hybrid pixel modules. Advantages of commercial CMOS processes are high throughput at comparatively low costs which makes them attractive for the usage of large-area detectors. Further benefits originate from multiple metal layers, metal–insulator–metal capacitors, and polysilicon layers which can

This paper reports on comprehensive efforts on uncertainty quantification and global sensitivity analysis for accelerator cavity design. As a case study object the TESLA shaped superconducting cavities, as produced for the European X-ray Free Electron Laser (EXFEL), are selected. The choice for these cavities is explained by the available measurement data that can be leveraged to substantiate the simulation

The possibility of using fast 14 MeV neutrons and the associated alpha particle technique, together with a library least-squares fitting technique to detect the various CW agents as well as explosives and narcotics were investigated. The Quality Assurance/Quality Control (QA/QC) procedures for neutron sensors were established and further developed for CW agents, with the aim to reduce the false positive

This work describes the design and realization of a radio frequency (RF) system with a single klystron to power two conjunct independent cavities, namely, an RF quadrupole (RFQ) and a drift tube linac (DTL). In contrast with a two-klystron scheme, an RF system that adopts a single-klystron scheme for two accelerating cavities exhibits simpler configuration, smaller occupation area, and lower cost.

As known, the detector response function in the detection of alpha particles is characterized by the following distributions: electronic excitation and ionization, electron–hole pair statistics, and electronic noise contribution. The distribution due to the ionization–excitation process is of particular relevance, because it is not Gaussian and contributes essentially to the asymmetry of the alpha

Over the years several rare-event search experiments have shown increasing interest to search for Fractionally Charged Particles (FCPs) within the data acquired in those experiments. This, in turn, has required the need for a framework to calculate accurately the energy loss expected from FCPs as they pass through the detector material. We have developed Monte Carlo methods within Geant4 to simulate

A semi-Lagrangian-type advection scheme, the constrained profile interpolation (CIP) method, is adopted to obtain a numerical solution of a drift–diffusion equation of photo-generated charge carriers in negatively biased, high-resistivity semiconductor detector materials. Transient current waveforms of high-resistivity CdZnTe measured by a time-of-flight (TOF) technique under different bias voltages

Detector gain saturation is a well-known issue with the chevron microchannel plate (MCP) detector configured with two MCPs, which is widely used in the time-of-flight (TOF) mass spectrometer. In these detectors, high-intensity signals saturate the gain stages, thus reducing the magnitude of subsequent signals. To solve this issue, we developed a new detector that combines an MCP with an avalanche diode

In 2016, the NATO Science for Peace and Security Programme funded research project ”Engineering Silicon Carbide for Border and Port Security” — E-SiCure was launched, its objective being the development of radiation-hard silicon carbide (SiC) based detectors of special nuclear materials (SNM), with the aim to enhance border and port security barriers. Detector prototypes based on SiC Schottky Barrier

This paper reports on the performance changes in CdTe:Cl semiconductor X-ray detectors seen after irradiation with 50 MeV protons up to a fluence of 1.6⋅1011cm−2. The rationale for the irradiation parameters is described. Performance was quantified before and after irradiations by obtaining X-ray spectra with a barium-133 radioactive source and detectors cooled to −20°C. Energy resolutions, electron

We report on the successful coupling of the Penning-trap mass spectrometry setup TRIGA-TRAP to the research reactor TRIGA Mainz. This offers the possibility to perform direct high-precision mass measurements of short-lived nuclei produced in neutron-induced fission of a 235U target located near the reactor core. An aerosol-based gas-jet system is used for efficient transport of short-lived neutron-rich

In the decommissioning of the Fukushima Daiichi Nuclear Power Station (FDNPS), the retrieval of the nuclear fuel debris is a critical step, and the localization of these debris speeds up the decommissioning operation and prevents criticality. Our work focused on the passive gamma-ray analysis (PGA) of the nuclear fuel debris based on measuring gamma rays with an energy greater than 1 MeV. The PGA requires

A 10Be beam having intensities up to 3 enA has been accelerated at the Tandem of the Laboratori Nazionali del Sud in Catania. The used 10Be was chemically extracted from a proton irradiated graphite target used for muon production at the Paul Scherrer Institute. In order to maximise the extracted current using a minimum amount of isotope, several preparatory tests, needed to optimise the preparation

As a new astronomical telescope for cosmic rays, DArk Matter Particles Explorer (DAMPE) have been operated in-orbit for more than four years since it was launched at the end of 2015. It could measure electron and gamma-ray ranging from 5 GeV to 10TeV to explore the brand new astrophysical phenomenon. As a very high energy telescope, the working lifetime is significant to accumulate high statistics

The present study focuses on the implementation of two X-ray phase contrast imaging (XPCI) techniques: free-space propagation (FSP) and single mask edge illumination (SM-EI) with a microfocus polychromatic X-ray source and a Timepix3 photon-counting detector with a CdTe sensor. This detector offers high spatial resolution, high detection efficiency and it is able to simultaneously record information

The timing and spectral characteristics of four highly efficient, slow fluors are presented for liquid scintillator solutions using linear alkylbenzene (LAB) as the primary solvent. The mixtures exhibit high light yields, but with rise times of several ns or more and decay times on the order of tens of ns. Consequently, such liquid scintillator mixtures can be used for effective separation of Cherenkov

In the context of the development of novel Thick GEM based detectors of single photons, the high spatial resolution optical system, nicknamed Leopard, providing a detailed surface scanning of these electron multipliers, has been used for a set of systematic measurements of their key properties. In particular, gain uniformity and photoelectron extraction dependence on geometry and electric field configuration

The technique for estimating the incident neutron energy distribution from emitted prompt gamma intensities from a system placed in a neutron field is validated using experimental data. A cylinder of high density polyethylene (HDPE) kept inside another cylinder of borated HDPE (BHDPE) placed in a neutron beam and the prompt gamma emissions are detected using a lead shielded NaI(Tl) detector based spectrometer

The Time-over-Threshold (ToT) analog-to-digital signal processing approach provides a power-efficient and cost-effective technique to extract all relevant information from detectors in high-energy physics and Positron Emission Tomography (PET) imaging. In this work, three calibration methods were investigated to correct the inherent nonlinear response of the ToT data using 1) γ-ray sources of various

The design and test results for a prototype laboratory device capable of condensing and solidifying gases is presented. This equipment is a new approach to the fabrication of NH3 material for polarized target experiments in nuclear physics experiments. The formed solids have a cylindrical geometry with 32 mm diameter and 50 mm height. With Computational Fluid Dynamics (CFD) analysis we designed and

In this work, we optimized the performance of a gallium nitride (GaN)-based n/p junction betavoltaic cell irradiated by the radioisotope nickel-63 (Ni63). In particular, we developed a lab-made software starting from an analytical model that takes into account a set of fundamental physical parameters for the cell structure. The simulations reveal that, by using a Ni63 radioisotope source with a 25

With the charged-particle decay spectroscopy extended to the proton drip-line region, half-lives of nuclei of interest decrease rapidly. Consequently, severe signal piling-up resulting from the implanted ions and their successive decays in position sensitive detectors become more and more common. To extract the spectroscopic information from the pile-up pulses with good accuracy, a digital pulse analysis

Mammography, ultrasound and magnetic resonance imaging are commonly used to diagnose breast cancer. However these imaging techniques produce a significant number of false positive results and lead to unnecessary biopsies. According to the American Cancer Society, more than 50% of breast biopsies turn out negative. Complementary non invasive diagnostic techniques, such as X-ray Diffraction (XRD), are