Table of contents

We introduce a new statistical test based on the observed spacings of ordered data. The statistic is sensitive to detect non-uniformity in random samples, or short-lived features in event time series. Under some conditions, this new test can outperform existing ones, such as the well known Kolmogorov-Smirnov or Anderson-Darling tests, in particular when the number of samples is small and differences occur over a small quantile of the null hypothesis distribution. A detailed description of the test statistic is provided including a detailed discussion of the parameterization of its distribution via asymptotic bootstrapping as well as a novel per-quantile error estimation of the empirical cumulative distribution. Two example applications are provided, using the test to boost the sensitivity in generic "bump hunting", and employing the test to detect supernovae. The article is rounded off with an extended performance comparison to other, established goodness-of-fit tests.

A second monolithic silicon pixel prototype was produced for the MONOLITH project. The ASIC contains a matrix of hexagonal pixels with 100 μm pitch, readout by a low-noise and very fast SiGe HBT frontend electronics. Wafers with 50 μm thick epilayer of 350 Ωcm resistivity were used to produce a fully depleted sensor. Laboratory and testbeam measurements of the analog channels present in the pixel matrix show that the sensor has a 130 V wide bias-voltage operation plateau at which the efficiency is 99.8%. Although this prototype does not include an internal gain layer, the design optimised for timing of the sensor and the front-end electronics provides a time resolutions of 20 ps.

The GRAPES-3 experiment located in Ooty, India, samples the electron and muon components in extensive air showers using an array of plastic scintillator detectors and a muon telescope (G3MT) consisting of proportional counters to study the composition of primary cosmic rays (PCRs) as well as γ-ray sources in the TeV–PeV energy range. The G3MT is designed with an appropriate mass absorber to shield the electromagnetic and hadronic components in the shower and to detect muons above 1 GeV×sec(θ) energy, incident from a zenith angle θ. We developed a simulation framework based on the GEANT4 toolkit to evaluate the response of shower particles such as muons, γ-rays, electrons and hadrons in the G3MT. We discuss the geometric modeling of the G3MT using GEANT4 starting with the proportional counter. We estimated the punch-through contribution of hadrons in the G3MT. We compare the simulated muon multiplicity distributions with the observed ones assuming PCR composition from a four population supernova remnant acceleration model namely H4a.

The High Energy cosmic-Radiation Detection facility (HERD) is a calorimetry-based cosmic-ray detection mission on board China space station. A side-on transition radiation detector (TRD) focuses on the TeV energy range calibration of the HERD calorimeter with an error of less than 10% by measuring the Lorentz factor γ of high-energy cosmic-ray protons. A side-on TRD prototype was developed for the performance study and tested by Deutsches Elektronen-Synchrotron electron beams. In this paper, the Monte Carlo simulation based on GEANT4 was compared with the experiment results. All simulations were in good agreement with the test beam results.

The manual measurement system for internal stress of acrylic was designed and realized, which is based on photo-elastic principle and spectrometric method. The manual measurement system can support mobile and quantitative measurement, and plays an important role in the fields of material research and engineering project. With the extensive application of the stress measurement system, automation is required to promote measuring efficiency and overcome the shortcomings of the manual measurement system. Electric control turntable was chosen as the key component for automation and adopted in the automatic measurement system. The automatic measurement system is controlled by program and user interface for operation has also been improved. The automatic measurement system has been realized and used for measuring internal stress of acrylic in the laboratory, which achieved the expected effect. The components of the automatic measurement system, the user interface for control program and data processing, and the stress measurements of the acrylic samples by the automatic measurement system are discussed in this article.

In this study, we use Monte Carlo method to conduct simulation research on a time projection chamber (TPC) which used for fission cross-section measurement. Based on Garfield, SRIM, COMSOL and other platforms and software, we explore the physical process during its actual operation, and analyze the simulation data. We carry out α particle track measurement experiments with U-235 ultra-thin target, and the measured results are in good agreement with the simulation results. This paper focuses on the simulation and reconstruction of particle tracks at different emission angles, and introduces the concept of ballistic deficit to correct the experimental measurement results. The corrected 2D distribution of particle track length and energy is closer to the theoretical model than the uncorrected distribution.

X-ray and gamma fluxes from the high intensity laser-plasma interaction are extremely short, well beyond temporal resolution of any detectors. If laser pulses come repetitively, the single photon counting technique allows to accumulate the photon spectra, however, its relation to the spectrum of the initial fast electron population in plasma is not straightforward. We present efficient and fast approach based on the Geant4 package that significantly reduces computer time needed to re-construct the high energy tail of electron spectrum from experimental data accounting for the pileup effect. Here, we first tabulate gamma spectrum from monoenergetic electron bunches of different energy for a given experimental setup, and then compose the simulated spectrum. To account for the pileups, we derive analytical formula to reverse the data. We also consider errors coming from the approximation of the initial electron spectrum by the sum of monoenergetic impacts, the finite range of the electron spectrum, etc. and give estimates on how to choose modelling parameters to minimize the approximation errors. Finally, we present an example of the experimental data treatment for the case of laser-solid interaction using 50 fs laser pulse with intensity above 10¹⁸ W/cm².

In this study, we investigated the effects of the motor unit (MU) location and size and the fibres pennation on the ability of anisotropic and almost isotropic spatial filters used to detect surface electromyographic (EMG) signals to make a distinction between motor unit action potentials (MUAPs) generated from two MUs. The study was based on simulated MUAPs. The fibres orientation was performed by varying the fibres pennation angle (FPA).

The root mean square error (RMSE) between MUAPs generated from two MUs was used as a criterion to evaluate the ability of the investigated filters to distinguish between two generated MUAPs. The location of a MU was fixed and the second MU moved away from the first MU in the transversal direction for the first case and in the depth direction in the second case to take five different locations in every case.

We showed that the capability of the studied filters to more separate two MUAPs strongly depended on MU location, MU size and FPA. This capability of separation was best with large distances between the two MUs and with large sizes of them. Furthermore, the main survey of this work was that the BiTDD filter has the best ability of separation of two MUAPs than the other filters in a given FPA interval. The number of pennation angles in this interval is related to the location and size of the moved MU.

To drive plasma current non inductively, a Lower Hybrid Current Drive (LHCD) system with a passive-active multijunction (PAM) antenna for injecting lower hybrid wave (LHWs) has been designed, fabricated and to be integrated with ADITYA-U Tokamak. A fast electron population in the energy range of a few keV to several hundreds of keV is generated with the injection of the LHWs. These fast electrons interacting mainly with ions and electrons result in Hard X-Ray (HXR) emission called Fast Electron Bremsstrahlung acronym as FEB emission. A single channel FEB detection system is being used in the earlier experiment of LHCD in ADITYA-U tokamak. However, the single channel detection system can't provide a radial emissivity profile of HXR intensity distribution. In order to determine a radial emissivity profile, for the first time, a multichannel FEB detection system is designed for ADITYA-U tokamak. This paper describes the detailed conceptual design for the selection of suitable detectors, optimization of the collimators, shielding geometry, and low energy filtering cut-off. In the present design analysis, the soller collimator concept is considered over a simple pinhole camera system due to its several advantages. In order to optimize the multichannel FEB system parameters for the best possible performance, a forwarded modelling code has been used. The signal to background ratio at each detector location has been estimated for a few system parameters and reported herein.

Digital signal processing has shown promise as a reliable approach for nuclear radiation spectroscopy. In this paper, the charge-to-digital conversion technique was applied to neutron-gamma discrimination. The method is based on the direct comparison of the charge at the fast and slow components of the anode signal of the scintillator detector. The performance of the technique was tested using experimental investigation by ²⁵²Cf source and D-D neutron generator. The minimum detectable energy for reasonable separation was found to be around 0.2 MeVee. The FOM of the discrimination parameter was maximized by the optimum selection of the charge integration parameters. Excellent discrimination between neutron and gamma signals was confirmed by the presented setup. The results confirmed that the presented technique can replace analog nuclear electronics conventionally uses for pulse shape discrimination.

An essential metric for the quality of a particle-identification experiment is its statistical power to discriminate between signal and background. Pulse shape discrimination (PSD) is a basic method for this purpose in many nuclear, high-energy and rare-event search experiments where scintillation detectors are used. Conventional techniques exploit the difference between decay-times of the pulses from signal and background events or pulse signals caused by different types of radiation quanta to achieve good discrimination. However, such techniques are efficient only when the total light-emission is sufficient to get a proper pulse profile. This is only possible when adequate amount of energy is deposited from recoil of the electrons or the nuclei of the scintillator materials caused by the incident particle on the detector. But, rare-event search experiments like direct search for dark matter do not always satisfy these conditions. Hence, it becomes imperative to have a method that can deliver a very efficient discrimination in these scenarios. Neural network based machine-learning algorithms have been used for classification problems in many areas of physics especially in high-energy experiments and have given better results compared to conventional techniques. We present the results of our investigations of two network based methods viz. Dense Neural Network and Recurrent Neural Network, for pulse shape discrimination and compare the same with conventional methods.

A silicon photomultiplier (SiPM) coupled Cs₂LiYCl₆:Ce³⁺ (CLYC) detector was developed for neutron detection in the narrow, mixed radiation field. Studies show that the SiPM and scintillator will suffer a certain degree of damage in high-intensity irradiation environments. To evaluate the effects of the radiation damage, the detector was exposed to a zero-power research reactor. The thermal neutron exposures ranged from 0 up to 7.60 × 10⁷ n/cm². The performance specifications on the gamma ray and thermal neutron pulses,  ⁶Li(n, α)³H thermal neutron peaks, energy resolutions, and pulse shape discrimination were analyzed. The results showed that the standard gamma ray and thermal neutron pulses were slightly altered, the thermal neutron peak centroid reduced by 40%, the energy resolution of the  ⁶Li(n, α)³H thermal neutron peak deteriorated from 15% to 21%, and the figure of merit of pulse shape discrimination decreased from 1.41 to 1.16. These variation curves can be applied to evaluate and correct the detector irradiation damage.

Identification and discrimination between BGO and LSO scintillators is a fundamental target for handling parallax error within positron emission tomography (PET) applications by depth of interaction. An approach is built for discrimination and identification of BGO and LSO scintillator crystals. This approach is tested using a simulated BGO and LSO pulses. A Matlab Simulink model is implemented for simulation and creation of BGO and LSO scintillation pulses. The simulated pulses depend on ²²Na radiation source. The suggested approach has two different algorithms. The first algorithm uses both 1D-Walsh ordered fast Walsh-Hadamard transform (1WFWHT) and fast Chebyshev transform (FCHT) for extracting the features of crystal pulses. The optimum features are selected from 1WFWHT and FCHT using one of three optimization techniques that are binary dragonfly optimization (BDA), binary atom search optimization (BASO) and binary Harris Hawk optimization (BHHO). These optimized features are trained and tested using one of three based classifiers. These classifiers are Naive Bayes classifier (NBC), hierarchical prototype-based (HP) classifier and adaptive neuro-fuzzy inference system (ANFIS) classification. The ANFIS classifier achieves the best accuracy with all optimum (BASO, BDF and BHH) FCHT features. However, the NB classifier introduces the highest accuracy with all optimum (BASO, BDF and BHH) FWHT 1D features. The second algorithm uses the conventional neural network (CNN) for extracting the pulse features. Then, the deep neural network (DNN) is applied for training and testing of the captured pulses. The suggested algorithms are verified and compared in respect of statistical measures. The compared results confirm that the best accuracy and identification rate is accomplished using DNN algorithm. Besides, the DNN has better results compared to conventional classification techniques with optimum feature selection techniques in respect of time consumption. The proposed approach aids in the realisation of overcoming parallax inaccuracy in PET.

The CALICE Semi-Digital Hadron Calorimeter technological prototype completed in 2011 is a sampling calorimeter using Glass Resistive Plate Chamber (GRPC) detectors as the active medium. This technology is one of the two options proposed for the hadron calorimeter of the International Large Detector for the International Linear Collider. The prototype was exposed in 2015 to beams of muons, electrons, and pions of different energies at the CERN Super Proton Synchrotron. The use of this technology for future experiments requires a reliable simulation of its response that can predict its performance. GEANT4 combined with a digitization algorithm was used to simulate the prototype. It describes the full path of the signal: showering, gas avalanches, charge induction, and hit triggering. The simulation was tuned using muon tracks and electromagnetic showers for accounting for detector inhomogeneity and tested on hadronic showers collected in the test beam. This publication describes developments of the digitization algorithm. It is used to predict the stability of the detector performance against various changes in the data-taking conditions, including temperature, pressure, magnetic field, GRPC width variations, and gas mixture variations. These predictions are confronted with test beam data and provide an attempt to explain the detector properties. The data-taking conditions such as temperature and potential detector inhomogeneities affect energy density measurements but have small impact on detector efficiency.

We present the first characterization results of Timespot1, an ASIC designed in CMOS 28 nm technology, featuring a 32 × 32 pixel matrix with a pitch of 35 μm. Timespot1 is the first small-size prototype, conceived to readout fine-pitch pixels with single-hit time resolution below 50 ps_rms and input rates of several hundreds of kilohertz per pixel. Such experimental conditions will be typical of the next generation of high-luminosity collider experiments, from the LHC run5 and beyond. Each pixel of the ASIC includes a charge amplifier, a discriminator, and a Time-to-Digital Converter with a time resolution indicatively of 22.6 ps_rms and maximum readout rates (per pixel) of 3 MHz. To respect system-level constraints, the timing performance has been obtained keeping the power budget per pixel below 40 mW. The ASIC has been tested and characterised in the laboratory concerning its performance in terms of time resolution, power budget and sustainable rates. The ASIC will be hybridized on a matched 32 × 32 pixel sensor matrix and will be tested under laser beam and Minimum Ionizing Particles in the laboratory and at test beams. In this paper we present a description of the ASIC operation and the first results obtained from characterization tests concerning its performance.

The present paper sheds light on designing a new and high performance microstrip diplexer. The latter is based on new octagonal meandrous resonators combined with the connected common port, without adding any transmission line junction, in order to get a miniaturized structure. The suggested compact resonator is formed through combining the octagonal meandrous lines and coupled lines, which create a bandpass filter. These filters operate at 3.5 GHz and 5 GHz which make them suitable for 5G and Wi-Fi applications. Accordingly, an approximated equivalent LC model of the presented octagonal meandrous resonator is suggested and analyzed so as to validate the simulation results. On top of that, the suggested diplexer is compact, as it occupies only 0.0768 λ_g × 0.024 λ_g. Thus, it attained excellent performance in terms of S-Parameters as the transmission coefficients are about -1 dB and the reflection coefficient is about -20 dB at both channels, whereas the isolation is about -25 dB. Hence, the validation of theoretical and simulated results is carried out through measurements of the manufactured prototype.

In the medical field, X-ray computed tomography (CT) is used to determine the size of defects and damage in an examined object, and to diagnose infectious diseases. Generally, data captured by 3D X-ray CT are viewed as images in three directions (sagittal, axial, and coronal) on a computer. However, augmented reality, virtual reality, and mixed reality are emerging as alternatives for imaging captured data for 3D X-ray CT and are used for medical simulations and educational purposes. Although these techniques are capable of 3D expression, they are limited to the representation of the surface structure of the object. The original function required of these technologies is to check the tomographic image of a specific part of the object by specifying any direction and position in three dimensions. This study proposes a method of representation in which a 2D digital imaging communication image is superimposed on a surface-rendered cross-section of an object. In addition, it proposes a pointing system using motion capture and a spatial reality display. The observer can confirm the object from any direction and understand the structure spatially. It can be moved and rotated with movements similar to actually holding, grabbing, moving, and rotating with hands. Moreover, the cross-section can be observed in any direction. In addition, by matching the respective scales of the device and application, the object can be represented with an error of less than 1 mm in the horizontal, vertical, and depth directions with respect to the actual object. Therefore, the proposed method is an effective 3D representation method in 3D X-rays, which are voxel data containing internal information. Furthermore, this method can easily indicate the desired location where the cross-section image can be viewed in a CT image. This study will help improve the efficiency of 3D X-ray inspection and surgery in the medical field.

The measurement of neutrino magnetic moment larger than 10^-19μ_B would be a clear signature of physics beyond the standard model other than the existence of massive Dirac neutrinos. The use of a spherical proportional counter detector filled with gas at 40 bar located near a nuclear reactor would be a simple way to perform such a measurement exploiting the developments made on such a technology for the search of dark matter and neutrinoless double beta decay. Different targets can be used just by replacing the gas: xenon, CF₄ and argon were compared and the sensitivity in one year of data taking could reach the level of 4.3 × 10^-12μ_B, 6.5 × 10^-12μ_B, and 8.5 × 10^-12μ_B, respectively.

A Fractal metasurface-based absorber is designed to obtain a wideband absorption in THz frequency band. The developed absorber has a broadband absorption over more than 600 GHz bandwidth, from 0.6 THz to 1.2 THz, with a minimum absorption percentage of 70% and total absorption from 1 to 1.1 THz. The proposed fractal structure is investigated using a Modified Split Ring Resonator (MSRR). The absorption coefficient of the proposed fractal metasurface is compared with the modified initially SRR metasurface. The results indicate that by using fractal design, the metasurface operating band is summed up, resulting in a wide bandwidth. The absorption coefficient of the proposed fractal metasurface is studied using two different simulation software programs to ensure the obtained results, with a high agreement between the results of them. The designed metasurface has a similar absorption response for the different polarization of the incident wave. The impedance of the designed metasurface indicates that, for the operating band, the fractal metasurface has a surface impedance of around 377 Ω, indicating a good matching between the designed metasurface and air. Different incidence and polarization angles are studied with results showing its insensitivity to both of them. The designed metasurface is compared with previously published works, showing wider bandwidth, higher absorption, and incidence and polarization insensitivity. The proposed metasurface absorber can be used for biomedical applications.

One of the decisive issues in the design and operation of cyclotrons is the choice of the beam extraction method. Typical methods are extraction by electrostatic extractors and by stripping. The former method requires DC high voltage electrodes which are notorious for high-voltage breakdowns. The latter method requires beams of atomic or molecular ions which are notorious for rest gas and Lorentz stripping. Here we discuss the conditions to be met such that a beam will leave the magnetic field of an isochronous cyclotron purely by fast acceleration.

The RIKEN RI (radioactive isotope) Beam Factory (RIBF) provides the world's most intense heavy ion beams exceeding 345 MeV/u and is the primary facility for in-flight RI beam generation. The RIBF has steadily improved its performance. In particular, the intensity of the uranium beam, which is critical for producing in-flight fission RI beams, has been dramatically increased by a factor of 240 compared to 2008. To further increase the intensity of the uranium beam, a new acceleration scheme using charge stripper rings (CSRs) has been proposed as a cost-effective way to increase charge stripping efficiency. In this paper, we discuss the key design issues of CSR and required upgrades of existing ring cyclotrons with the introduction of CSR and space-charge effects.

Stripping extraction of hydrogen molecular ions has gained interest in the cyclotron industry due to its high extraction efficiency. However, the magnetic field could result in undesired Lorentz dissociation of the hydrogen anion/molecular ions during acceleration. Studies of dissociation under electric fields comparable to that of a Lorentz-transformed magnetic field in a typical cyclotron (a few MV/cm) are sparse. Hence, in order to fill in the missing yet crucial information when designing a cyclotron, this work compiles and summarizes the study of Lorentz dissociation of H^-, H⁺₂ and H⁺₃ for stripping extraction in a cyclotron.

At IBA a high-intensity compact self-extracting cyclotron is being studied. There is no dedicated extraction device but instead, a special shaping of the magnetic iron and the use of harmonic coils to create large turn-separation. Proton currents up to 5 mA are aimed for. This would open new ways for large-scale production of medical radioisotopes. The main features of the cyclotron are presented. A major variable of the beam simulations is the space charge effect in the cyclotron centre. Using the SCALA-solver of Opera3D, we attempt to find the ion source plasma meniscus and the beam phase space and current extracted from it. With these properties known, we study the bunch formation and acceleration under high space charge condition with our in-house tracking code AOC. We also discuss a new tool that automates optimization of cyclotron settings for maximizing beam properties such as extraction efficiency.

Existing analytical models for transverse beam dynamics in isochronous cyclotrons are often not valid or not precise for relativistic energies. The main difficulty in developing such models lies in the fact that cross-terms between derivatives of the average magnetic field and the azimuthally varying components cannot be neglected at higher energies. Taking such cross-terms rigorously into account results in an even larger number of terms that need to be included in the equations. In this paper, a method is developed which is relativistically correct and which provides results that are practical and easy to use. We derive new formulas, graphs and tables for the radial and vertical tunes in terms of the flutter, its radial derivatives, the spiral angle and the relativistic gamma. Using this method, we study the 2ν_r = N structural resonance (N is number of sectors) and provide formulas and graphs for its stopband. Combining those equations with the new equation for the vertical tune, we find the stability zone and the energy limit of compact isochronous cyclotrons for any value of N. We confront the new analytical method with closed orbit simulations of the IBA C400 cyclotron for hadron therapy.

Compact H^- cyclotrons are used all across the globe to produce medical isotopes. Machines with external ion sources have demonstrated average extracted currents on the order of a few mA, although reported operational numbers are typically around 1 mA or below. To explore the possibility of extracting even more current from such cyclotrons, it is important to understand the mechanisms that drive intensity limits and how they scale. In this paper we review some of the key aspects of the beam dynamics in the central region of compact cyclotrons, including rf electric focusing and space charge effects. We derive the scaling of the phase acceptance with the rf gap voltage, harmonic number, etc. We also explore the scaling with different types of ions such as H^-, H⁺₂ and H⁺₃. We discuss the impact of mechanical erosion of the central region electrodes. Thoughout the paper, we use examples and experimental data from two compact H^- cyclotrons for reference: the TR-30 series and the TRIUMF 500 MeV machine.

We're concerned with future accelerators of high intensity protons for isotope production. To this end, we initiate a proposal to design an innovative superconducting H⁺₃ cyclotron TR150, aiming at proton energy of 70–150 MeV and proton current of ∼ 1.0 mA. Cyclotrons in this energy range are not developed world-wide; moreover numerous highly interesting and increasingly demanded radio­nuclides are in this energy range. Our machine shall be designed to accelerate H⁺₃ ion, the simplest and stable triatomic molecular ion, by injection from an external ion source and extraction by stripping. This has potential to extract proton beam of variable energies with very high extraction efficiency, and thus enables to simultaneously provide multiple proton beams for multiple external production targets. A baseline design of our machine and the beam dynamics studies are presented in this paper.

The MW class proton accelerators are expected to play important roles in many fields, attracting institutions to continue researching and tackling key problems. The continuous wave (CW) isochronous accelerator obtains a high-power beam with higher energy efficiency, which is very attractive to many applications. Scholars generally believe that the energy limitation of the isochronous cyclotron is ∼1 GeV. To get higher beam power by the isochronous machine, enhancing the beam focusing become the most important issue.

Adjusting the radial gradient of the average magnetic field makes the field distribution match the isochronism. When we adjust the radial gradient of the peak field, the first-order gradient is equivalent to the quadrupole field, the second-order, the hexapole field, and so on. Just like the synchrotron, there are quadrupoles, hexapole magnets, and so on, along the orbits to get higher energy, as all we know.

If we adjust the radial gradient for the peak field of an FFA's FDF lattice and cooperate with the angular width (azimuth flutter) and spiral angle (edge focusing) of the traditional cyclotron pole, we can manipulate the working path in the tune diagram very flexibly. During enhancing the axial focusing, both the beam intensity and the energy of the isochronous accelerator are significantly increased. Here a 2 GeV CW FFA with 3 mA of average beam intensity design is presented. It is essentially an isochronous cyclotron although we use 10 FDF lattices. The key difficulty is that the magnetic field and each order of gradient should be accurately adjusted in a large radius range.

As a high-power proton accelerator with high energy efficiency, we adopt high-temperature superconducting (HTS) technology for the magnets. 15 RF cavities with a Q value of 90000 provide energy gain per turn of ∼15 MeV to ensure the CW beam intensity reaches 3 mA. A 1:4 scale, 15-ton HTS magnet, and a 1:4 scale, 177 MHz cavity have been completed. The results of such R&D will also be presented in this paper.

An accurate and detailed field map is important for cyclotron beam dynamics studies. During the long history of cyclotron studies, many techniques have been developed by cyclotron pioneers for the treatment of median plane field map. In this paper, we take the TRIUMF 500 MeV cyclotron as an example to study the asymmetric field resulting from imperfect median plane symmetry. The "Gordon approach" and a highly accurate compact finite differentiation method are used to investigate the historical field survey data. The redundancy in the survey data is revealed by the expansion method, which also makes it possible to correct the error in the measurement. Finally, both the azimuthal field B_θ and the axial gradient of the axial field dB_z/dz in the median plane are corrected using the radial field map B_r. The influence of the correction is examined by recalculating the equilibrium orbit properties of the TRIUMF cyclotron. The result shows significantly increased vertical centering errors of the closed orbits. A further simulation study suggests that these centering errors can be reduced to below 1.5 cm by adjusting the trim coils' B_r field within the output limits of our trim coils' power supplies. The error in the measurement field data may explain why the calculated trim coils' settings during the cyclotron commissioning in 1974 encountered difficulty.

The linear coupling resonance ν_r - ν_z = 1 in a cyclotron is driven by the first harmonic in the radial gradient of the radial magnetic field. In the TRIUMF 500 MeV cyclotron, this resonance is encountered multiple times. When the circulating beam is off-centred radially passing through the resonance, the radial betatron oscillation can be converted into vertical oscillation, which can cause beam losses and radio-activation. We investigated this resonance with goal to correct it by using the available harmonic correction coils. Moreover, we improved the cyclotron vertical tune measurement by using trim coils to create a flat-top radial field, and thus confirmed an extra ν_r - ν_z = 1 coupling resonance passage as this is unexpected from the historical tune diagram. To avoid this passage, the local vertical tune is adjusted to stay farther away from the resonance line by using the trim coils axial field, but at the cost of a local excursion in isochronism. After the correction and the avoidance of this resonance, both the coherent and incoherent vertical oscillations are decreased, thus helping to reduce the machine tank spills under high intensity operation. In this paper, we present the results of calculations and simulations as well as measurements that we undertook.

In this paper we demonstrate that cyclotrons can be made to have precisely constant betatron tunes over wide energy ranges. In particular, we show that the horizontal tune can be made constant and does not have to follow the Lorentz factor γ, while still perfectly satisfying the isochronous condition. To make this demonstration we developed a technique based on the calculation of the betatron tunes entirely from the geometry of realistic non-hard-edge closed orbits. We present two particular cyclotron designs, one compact cyclotron and one ring cyclotron. The compact cyclotron design is backed up by a 3-dimensional finite element magnet calculation, that we also present here.

The statistical σ-matrix approach is used to derive general envelope equations for ellipsoidal bunches with space charge in isochronous and non-isochronous fixed-field accelerators (FFAs) These accelerators couple the radial and longitudinal phase spaces due to momentum dispersion induced by the space charge effect. This generates a rotation of the bunch around the local vertical axis which is known in the field as the vortex effect. A special invariant of the vortex is found which represents its total angular momentum with respect to its center. For the isochronous cyclotron, a special solution of the envelope equations is found which describes a circular bunch with equal radial and longitudinal RMS sizes. The existence of this solution is a direct consequence of the circular symmetry of the single particle Hamiltonian in a co-moving coordinate frame. The stationary solution of the circular bunch fixes the relation between bunch sizes and accelerated current (or the total charge per bunch) for given emittances. The general envelope equations may easily be implemented in existing numerical envelope codes.

Muon Tomography is a promising technique for detecting the presence of high atomic number (Z) material, using naturally available cosmic muons. The reconstruction algorithms used in Muon Tomography need to process a considerably high number of muon tracks to reconstruct the image of the object under test. This makes the image reconstruction process computation-intensive and time-consuming. The algorithms to process the muon tracks are event-based algorithms, where all the events are independent and can be processed in any order. The traditional form of parallelism tries to distribute a small segment of work to multiple computing cores, but does not utilize the data level parallelism. The event-based algorithm can be processed on vector architecture and can provide a path to better utilize the data level parallelism. This approach provides another level of parallelism on standard computers without the need for specialized hardware. In this paper, we have tried to exploit the vector architecture provided by the current generation of CPUs to implement the vectorized version of Point of Closest Approach (PoCA) reconstruction algorithm for Muon Tomography. Results are presented using different vector instruction sets, for single-precision and double-precision calculations.

Polytetrafluoroethylene (PTFE) is an excellent diffuse reflector widely used in light collection systems for particle physics experiments. In noble element systems, it is often coated with tetraphenyl butadiene (TPB) to allow detection of vacuum ultraviolet scintillation light. In this work this dependence is investigated for PTFE coated with TPB in air for light of wavelengths of 200 nm, 260 nm, and 450 nm. The results show that TPB-coated PTFE has a reflectance of approximately 92% for thicknesses ranging from 5 mm to 10 mm at 450 nm, with negligible variation as a function of thickness within this range. A cross-check of these results using an argon chamber supports the conclusion that the change in thickness from 5 mm to 10 mm does not affect significantly the light response at 128 nm. Our results indicate that pieces of TPB-coated PTFE thinner than the typical 10 mm can be used in particle physics detectors without compromising the light signal.

This study is focused on an investigation of the performance of the Short Strip module developed by the ATLAS Inner Tracker (ITk) strip collaboration using electron beams of energy 5.4 GeV and 5.8 GeV at the DESY-II Testbeam Facility. The noise at +30 °C and -30 °C was measured. The ratio of the two measurements is compared with a circuit-model calculation. The measured noise at -30 °C is compared with the maximum noise that would correspond to an acceptable signal-to-noise ratio after the expected radiation damage from operation at HL-LHC. The measured charge distributions at +30 °C and -30 °C are compared with GEANT4 simulations. The detection efficiency and noise-occupancy were measured as a function of threshold at both +30 °C and -30 °C. The average cluster width was measured as a function of threshold. Scans of detection efficiency versus threshold at different delay settings were used to reconstruct the pulse shape in time. The resulting pulse shape was compared with a circuit model calculation.

Performing accurate and reliable dosimetry in spatially fractionated beams remains a significant challenge due to the steep dose gradients and microscopic scale of features. This results in many conventional detectors and instrumentation being unsuitable for online dosimetry, necessitating frequent offline validation using radiochromic film.

In this study, the use of a Complementary Metal-Oxide-Semiconductor (CMOS) detector for evaluation of relative real-time dosimetry of proton minibeam radiation therapy (pMBRT) was investigated. The linearity of the CMOS detector was investigated by varying the proton beam current, with a comparison to a PTW 34001 Roos ionisation chamber used to carry out an independent check. It was found that the relative peaks and valleys of the pMBRT beam could be measured, with results comparable to EBT3XD film. The high sensitivity of the CMOS detector meant it was able to measure dose profiles from peak to valley regions, something not possible with the EBT3XD. The CMOS detector was compared to the treatment delivery log files, with correlation in beam position seen as the beam is scanned along each slit, but not across; and agreement in beam intensity, with the CMOS detector able to observe beam interruptions.

Lastly, the CMOS detector was used in conjunction with the NPL primary-standard proton calorimeter (NPL PSPC) for a preliminary study on combining the NPL PSPC with high resolution temporal information about the incident pMBRT beam. The ultimate aim of this approach is to facilitate detailed thermal modelling to reduce the overall uncertainty in the absolute dose measured from the calorimeter. In these experiments, saturation in the CMOS pixels prevented further thermal modelling of the radiation induced heat flow, however the instantaneous dose rate was observed to be comparable with the predicted NPL PSPC response obtained by masking the CMOS detector.

Finite element analysis (FEA) of ultrahigh vacuum ConFlat-type flange joints for both Wheeler's and CERN's models were carried out. These models differ in the angle of inclination between the two shelves of knife-edge. The main value of this research is a computer simulation for deformable flanges and gaskets because all analyses before this have been done for absolutely rigid flanges (non-deformable flanges) and deformable gaskets. The analysis variable parameters are the radius of rounding at the tip of the knife-edge (0.05 ... 0.2 mm), the angle between the shelves forming the knife-edge (70° and 90°) and the material properties of the copper ring (annealed and 1/4 hard). The calculation of bolted connections for tightening the flanges was also carried out as the experience has shown that during the tightening of bolts, they reach the yield point and begin to deform plastically. That leads to incomplete tightening of the flanges and, therefore incomplete sealing of the joint. The experimental research of the flanges tightening and the comparison with computer simulation results were carried out.

Filter stack spectrometers are widely employed in laser facilities for the spectrum measurement of bremsstrahlung photons. However, this method suffers from large uncertainty of unfolding due to its intrinsic limit resolution. For this, an optimization study on filter stack spectrometer is conducted. This procedure is implemented by a hybrid particle swarm optimization and genetic algorithm (PSO-GA). Monte-Carlo particle transport code Fluka is used for the simulation of the response matrix. Gravel algorithm, based on the least-square method, is used for the unfolding. For mono-energetic photons, this optimized filter stack spectrometer design provides a better energy resolution. For continuous distribution, this optimized filter stack spectrometer design yields a narrower unfolding solution space in the presence of measurement error.

The detection system of the Kyungpook National University Advanced Positronium Annihilation Experiment (KAPAE) has a 4π coverage with fine segmentation for measuring multi- photon decays of positronium to improve the charge (C), charge-parity (CP), and charge-parity-time reversal (CPT) violations in lepton sector as well as for studying rare decays. In addition, various exotic decays of positronium can be studied with the KAPAE detector. In the KAPAE, all aspects of the detector design, fabrication, and data analysis for physics studies related to positronium annihilation are covered. In this paper, we describe the above-mentioned first fully assembled detection system developed for KAPAE, which consists of a trigger and a gamma-ray detector. The newly proposed multi-layered trigger consists of a ²²Na positronium source deposited on a plastic scintillator and a silicon photomultiplier (SiPM), and the gamma-ray detector contains an aerogel at the centre in a nitrogen environment. The gamma-ray detector minimizes pile-up events by fine segmentation of 196 Bi₄Ge₃O₁₂ (BGO) crystal scintillators, whose scintillation lights from both sides are readout by the SiPM. The signals of a 392-channel SiPM are fed to a preamplifier followed by a 65 MHz flash analog-to-digital converter (FADC). In this paper, the KAPAE detector design, fabrication, and performance are presented.

DIET is a 64-channel SiPM readout ASIC for TOF-PET and can measure energy and arrival time independently for each channel. With the increasing requirements for time measurement precision, the timing performance of the DIET chip has been fully evaluated in this paper. The noise sources in the time processing chain, especially in the TDC, were theoretically analysed, and a dedicated test system was built. The time jitter of the analogue front end and the TDC were measured and analysed. The test results show that the total jitters of the analogue front-end and the TDC are 24 ps and 22 ps RMS at 50 p.e. input signal, respectively. The percentages of the contribution by INL, thermal noise, and quantization noise of the TDC are 70%, 16.6%, and 13.4%, respectively. The DIET chip was also tested with SiPM and LYSO detectors. A CRT resolution of 244 ps FWHM was achieved using two single 3 × 3 × 16 mm³ crystals.

With the wide application of the coded-aperture gamma-ray camera in the field of nuclear radiation monitoring, research on its imaging performance of radioactive point sources has increasingly matured. However, because of the difficulty in obtaining complex radioactive plane sources with specific activity distributions, there is a lack of experimental research on imaging performance of such sources currently, the main focus being on simulation research and on-site imaging trials. In addressing the issue, we proposed a method to assess image quality of coded-aperture gamma-ray camera to such sources, and performed imaging experiments with a custom-made gamma-ray camera. Driven by a two-axis computer-numerical control (CNC) motion platform, a point source was moved through prescribed paths at a given velocity, from which a custom activity distribution plane source for coded-aperture imaging was constructed. Peak signal-to-noise ratio and structural index similarity were the two indicators used to evaluate the imaging quality of the plane source for seven distinct shapes. The results indicate that the imaging quality of the plane source imaged by our custom-made camera and constructed using our method is excellent with these two indicators being better than 17 dB and 0.996, respectively. Our method provides good reliability and practicality, and offers an alternative approach for assessing imaging quality of coded-aperture gamma-ray camera for complex radioactive plane sources.

We propose using a Genetic Algorithm to improve the efficiency of reflexive surfaces in devices where the receiver's position is different from the classic parabolic antenna. With this technique, we show that we can improve the efficiency of the ARAPUCA photodetector.

Inorganic scintillators are widely used for scientific, industrial and medical applications. The development of 3D printing with inorganic scintillators would allow the fast creation of detector prototypes for the registration of ionizing radiation, such as alpha, beta and gamma particles in thin layers of active material, and X-ray radiation. This article reports on the technical work and scientific achievements that aimed at developing a new inorganic scintillation filament to be used for the 3D printing of composite scintillator materials: study and definition of the scintillator composition; development of the methods for the inorganic scintillator filament production and further implementation in the available 3D printing technologies; study of the impact of the different 3D printing modes on the material scintillation characteristics. Also, 3D-printed scintillators can be used to produce combined detectors for high-energy physics.

A suitable neutron source is indispensable for boron neutron capture therapy (BNCT). This article proposes a design of beam shaping assembly (BSA) for an accelerator-based BNCT (AB-BNCT) epithermal neutron source facility using ⁷Li(p,n)⁷Be reaction, and the results show that all parameters of BSA meet the recommended values of International Atomic Energy Agency (IAEA). The dose distribution and parameters in the Snyder head phantom are calculated using the Monte Carlo simulations to evaluate the performance of the epithermal neutron beam.

Ultra-short, ultra-intense laser pulses can create extreme physical conditions for a wide range of applications in atomic and molecular physics, materials chemistry, and inertial-confinement fusion. However, laser-matter interactions can be accompanied by significant X-ray emission that introduces radiation risks to the nearby environment and personnel. It is usually to monitor the radiation dose during in high-intensity laser-target interactions with optically stimulated luminescence and thermo-luminescence devices. However, these passive methods cannot measure the radiation dose in real time, while most active dosimeters cannot accurately measure pulsed radiation doses. Here, transient pulse X-ray radiation doses are converted by CdWO₄ crystals into slow signals. Because the crystals have a 14-μs luminescence decay time, they can absorb sub-nanosecond X-ray pulses and release the energy at a 100-μs rate, thus reducing the linear-response pressure of subsequent devices. A pulse detector based on a CdWO₄ crystal, a phototube, and a custom signal-processing circuit was developed. Experiments were performed at the 45-TW femtosecond laser facility of the Laser Fusion Research Center. The detector deviation was less than ±20% relative to that of an ionization-chamber detector. This initially verified its feasibility for real-time pulsed X-ray radiation detection.

The Super Tau Charm Facility (STCF) is a proposed electron-positron collider working at √s = 2 ∼ 7 GeV, and the peak luminosity is designed to be above 0.5 × 10³⁵ cm^-2s^-1. The huge amount of scientific data brings great challenges to the offline data processing software, including the Monte Carlo simulation, calibration, reconstruction as well as the data analysis. To facilitate efficient offline data processing, the offline software of Super Tau Charm Facility (OSCAR) is developed based on SNiPER, a lightweight framework designed for HEP experiments, as well as a few state-of-art software in the HEP community, such as podio and DD4hep.

This paper describes the design and implementation of the core software of OSCAR, which provides the foundation for the development of complex algorithms to be applied on the large data sets produced by STCF, particularly the way to integrate the common HEP software toolkits, such as Geant4, DD4hep and podio, into SNiPER. The software framework also provides a potential solution for other lightweight HEP experiments as well.

A convolutional neural network (CNN) architecture is developed to improve the pulse shape discrimination (PSD) power of the gadolinium-loaded organic liquid scintillation detector to reduce the fast neutron background in the inverse beta decay candidate events of the NEOS-II data. A power spectrum of an event is constructed using a fast Fourier transform of the time domain raw waveforms and put into CNN. An early data set is evaluated by CNN after it is trained using low energy β and α events. The signal-to-background ratio averaged over 1–10 MeV visible energy range is enhanced by more than 20% in the result of the CNN method compared to that of an existing conventional PSD method, and the improvement is even higher in the low energy region.

To reduce the lower detection limit of ¹³N gas, we design a γ-γ coincidence measuring instrument including two detectors, a sampling vessel, and a summation and coincidence circuit in this work. The detector uses a 13 cm × 5 cm oversized Bi₄Ge₃O₁₂  (BGO) scintillator and 172 silicon photomultiplier (SiPM) tubes, which greatly reduce the instrument size while improving the coincidence detection efficiency. The ¹³N gas coincidence detection efficiency is improved by installing a multilayer metal absorber plate inside the cylindrical sampling vessel. Due to the short half-life of ¹³N gas, it cannot be stored for a long time; additionally, it is difficult to obtain. It is not possible to directly scale the coincidence detection efficiency of this instrument using a ¹³N gas source with known activity in engineering projects. Based on the spatial distribution of the relative efficiency of the sampling vessel and the absolute efficiency of the reference point, we use a combination of ²²Na solid point source experiments and Monte Carlo simulations to calculate the coincidence detection efficiency of this instrument for ¹³N gas in this work; the coincidence detection efficiency is approximately 4%, which meets the engineering design requirements.

Ultrasonic non-destructive testing (NDT) is one of the prominent field involving inspection to evaluate defects, cracks, deposition or fusion of welding materials and dimensional measurements of the test piece(s). Ultrasonic immersion scanning systems are useful for various industrial and metrological applications. The conventional immersion system uses a dedicated pulser receiver module for the excitation and detection of signal from transducer and a fast analog data acquisition card (DAQ) to acquire the raw data into computer. Rigorous digital signal processing and filtering is used to extract desired information from the raw data. In the present work, development of an ultrasonic immersion C-scan testing system, intended for industrial and metrological applications, is described. The developed system uses a commercial ultrasonic flaw detector (UFD) for the data acquisition rather than using pulser receiver and DAQ card to acquire ultrasonic information. The software for the same has been developed in Visual Basic .NET framework to control all five servo motor based axes of the ultrasonic immersion scanning tank. The developed software scans the sample automatically with parameters specified by the user. The parameters include echo amplitude, echo location, separation between two echoes, and ultrasonic attenuation. The developed software generates the data files that can later be used for further analysis using suitable data analysis software such as Origin or MS excel. The functionality of the developed system has been tested for the detection of flaws present in the material, testing for thickness variation and ultrasonic attenuation. The developed system is capable of detecting the location of defects within the resolution of ±0.01 mm. Ultrasonic transducer movement resolution of ±0.01 mm over the sample, results in to generation of a high quality image.

Silicon photonics technology promises significant improvements for fibre optic links of future upgrades of HEP experiments. Such systems will require high levels of radiation tolerance and silicon photonics modulators have been shown to be very robust when exposed to high levels of radiation under certain conditions. We demonstrate for the first time that changing the temperature of ring modulators during or after irradiation can significantly improve their performance.

The DARWIN project aims to build and operate a next-generation observatory for dark matter and neutrino physics, featuring a time projection chamber with a proposed active target of 40 t of liquid xenon. As an R&D facility to test fundamental components of the future detector, Xenoscope, a full-scale vertical demonstrator with ∼400 kg of liquid xenon and up to 2.6 m electron drift length, was built at the University of Zurich. Its main objective is to demonstrate electron drift over unprecedented distances in liquid xenon—first in a purity monitor setup with charge readout, followed by a dual-phase time projection chamber. In this second phase, an array of 48 VUV4 MMPCs from Hamamatsu (model S13371-6050CQ-02) with a 12-channel readout will be placed above the liquid xenon column and operated as a light readout for the secondary proportional scintillation signals coming from extracted electrons in the time projection chamber. This work presents the design and development of the silicon photomultiplier array of Xenoscope, covering the structural and electronic design, sensor characterisation at cryogenic temperature and signal simulation.

Teaching quantum communication is a challenging task when involving different technical and engineering backgrounds. The use of an approach that exploits the knowledge of these profiles, as well as other technological resources available for demonstrations or exercises, enhances this teaching. This paper presents as an example the "Quantum Communications Lab" that took place at the 6th INFIERI Summer School in 2021. In this lab, the access to the Madrid Quantum Communication Infrastructure (MadQCI) was an important resource available.

CMAM is a multidisciplinary-oriented scientific facility based on the operation of a 5 MV tandem ion accelerator and a suite of six beamlines, along with complementary infrastructures and scientific tools. This work describes CMAM, highlighting some of the present and future collaborations and standing out radiobiology (in particular Proton-therapy) as a strategic research line with high societal relevance. Proton-therapy has been, since the last thirty years, an alternative to conventional radio-treatment to heal or control radio-resistant cancers or tumours near sensitive organs such as spinal cord or brain tumours. The research in this field has a multidisciplinary approach since biologist, chemists and physicist must work together to detangle the different effects that are produced by the radiation. Flexible facilities such as CMAM may play a very relevant role in order to develop further basic knowledge and as a training field for students to this type of investigation. As an example of this, a preliminary radiobiology experiment is briefly described, in which a non-alive material with a similar composition than a cell culture was used to see the effects of the radiation and it was developed the basic methodologies for dose delivery and proton range control. The experiment was also used as a training practice for students in the framework of the INFIERI school conducted at Universidad Autónoma de Madrid in Summer 2021.

Current generation of detectors using noble gases in liquid phase for direct dark matter search and neutrino physics need large area photosensors. Silicon based photo-detectors are innovative light collecting devices and represent a successful technology in these research fields. The DarkSide collaboration started a dedicated development and customization of SiPM technology for its specific needs resulting in the design, production and assembly of large surface modules of 20 × 20 cm² named Photo Detection Unit for the DarkSide-20k experiment. Production of a large number of such devices, as needed to cover about 20 m² of active surface inside the DarkSide-20k detector, requires a robust testing and validation process. In order to match this requirement a dedicated test facility for photosensors was designed and commissioned at INFN-Naples laboratory. The first commissioning test was successfully performed in 2021. Since then a number of testing campaigns were performed. Detailed description of the facility is reported as well as results of some tests.

We present a new state-of-the-art Triple Wavelength Spectrometer (TriWaSp), recently deployed on ST40, a high field low aspect ratio spherical tokamak. The TriWaSp has a range of possible applications due to its flexible design; the current configuration focuses on charge exchange recombination spectroscopy from carbon and neon impurities in the ST40 plasma. This paper discusses the detailed setup of the system and presents initial charge exchange ion temperature measurements using a single line of sight, which show good agreement with other ion temperature diagnostics. Building on these commissioning results and forward modelling of the system, a new observation geometry has been implemented for the next experimental campaign which will considerably improve the localisation of ion temperature and velocity profile measurements.

A method of automating the visual inspection of ATLAS upgrade strip modules is shown. The visual inspection of the hybrids is a time consuming part of the quality control during module production. A method of detecting and classifying the SMD components on the hybrids using an object detection neural network was investigated. The results show that the amount of hybrids that needed to be check by a human operator was reduced to around 10% of the batch. This hugely reduced the amount of time needed for human inspection and did find real mistakes done during the production of the hybrids.

After Run III the ATLAS detector will undergo a series of upgrades to cope with the harsher radiation environment and increased number of proton interactions in the High Luminosity LHC. One of the key projects in this suite of upgrades is the ATLAS Inner Tracker (ITk). The pixel detector of the ITk must be read out accurately and with extremely high rate. The Optosystem performs electrical-to-optical conversion of signals from the pixel modules. We present a general overview on the design of the Optosystem and recent results related to the performance of the data transmission chain, pivoted on the Optoboards, and to the radiation hardness of the ASICs housed on it.

The ATLAS trigger system includes a Level-1 (L1) trigger based on custom electronics and firmware, and a high-level software trigger running on off-the-shelf hardware. The L1 trigger system uses information from the forward detectors, the calorimeters and the muon trigger detectors. Once information from all muon trigger sectors has been received, trigger candidate multiplicities are calculated by the Muon-to-Central-Trigger-Processor Interface (MUCTPI). Muon multiplicity information is sent to the Central-Trigger-Processor (CTP) and trigger objects are sent to the L1 Topological Trigger Processor (L1Topo). The CTP combines the information received from the MUCTPI with the trigger information from the forward detectors, the calorimeters and the L1Topo, and takes the L1 trigger decision. As part of the ATLAS L1 trigger system upgrade for Run-3 of the Large Hadron Collider (LHC) a new MUCTPI has been designed and commissioned. We discuss the commissioning and operation of the new MUCTPI used in ATLAS from the beginning of Run-3. In particular, we describe the integration tests which have been carried out for the commissioning and operation of the new MUCTPI.

ST40 is a high field low-aspect ratio spherical tokamak built and operated by Tokamak Energy Ltd. Recent plasma operations were aimed at exploring operational scenarios to maximise the central plasma temperature and have culminated in the achievement of thermal ion temperatures of over 9 keV. This paper presents ion temperature and toroidal rotation measurements performed on ST40 during the 2021–22 campaign for a range of different scenarios. Several independent diagnostic systems are used, analysing their correlation and interpreting their differences using new diagnostic forward models.

Detectors for direct dark matter search using noble gases in the liquid phase as a detection medium need to be coupled to liquefaction, purification and recirculation systems. A dedicated cryogenic system has been assembled and operated at the INFN-Naples cryogenic laboratory with the aim to liquefy and purify the argon used as an active target in liquid argon detectors to study the scintillation and ionization signals detected by large SiPM arrays. The cryogenic system is mainly composed of a double wall cryostat hosting the detector, a purification stage to reduce the impurities below one part per billion level, a condenser to liquefy the argon, and a recirculation gas panel connected to the cryostat equipped with a custom gas pump. The main features of the cryogenic system are reported as well as the performance, long term operation and stability in terms of the most relevant thermodynamic parameters.

For the high-luminosity phase of the LHC, which begins operation in 2029, the current ATLAS inner detector will be replaced by a new tracker, the ITk. The ITk consists of two subdetectors, one using pixels and the second using silicon-strips, the ITk Strip detector. The HCC and AMAC chip are radiation-tolerant ASICs that contribute to the front-end readout, monitoring and control of the ITk Strip subsystem. Low temperature startups and low internal regulated voltage tests have been performed on HCC and AMAC to guarantee their reliability at edge operation conditions. In addition, to ensure the operation of the HCC and AMAC under a radiation heavy environment, gamma and x-ray irradiation campaigns were conducted. HCC and AMAC successfully operated at harsher conditions than the ones expected during the HL-LHC.

In the context of the high-luminosity upgrade of the LHC and ATLAS, the microstrip-tracking detector will be redesigned. The main building blocks are substructures with multiple sensors and their electronics. Each substructure will have a single interface to the off-detector system, the so-called End-of-Substructure (EoS) card. Its physical realisation is a set of printed circuit boards (PCBs). The PCB integrates ASICs and hybrids, which multiplex or demultipex the data and transmit with a rate up to 10 Gb/s or receive with a rate up to 2.5 Gb/s on optical fibres. These active parts are developed at CERN and are known as lpGBT and VTRx+. The EoS card integrates the active parts with the required electronics for the specified operation and within the mechanical constraints of the detector. In this paper critical design aspects such as the low-impedance powering scheme and the PCB setup are described. The EoS card has reached its final state for a series production, including the required setups for quality control. The achieved transmission quality on the 10 Gb/s links is presented.

A new high-granularity endcap calorimeter, HGCAL, is foreseen to be installed later this decade in the CMS experiment. We present the design and performance of the Hexaboard, a complex hexagonal multi-layer PCB equipped with multiple HGCROC ASICs to read out the signals from silicon pads with low noise and large dynamic range. The Hexaboards are glued to silicon sensors and connect to their pads via wire bonds through holes in the PCBs. The Hexaboard also connects to mezzanine boards for powering, trigger and data concentration and transfer. More than ten variants of the Hexaboard are required to cover the circular fiducial area of the CMS endcaps. Detailed performance measurements, and comparative PCB simulations using Ansys SIwave, are presented.

In order to validate the design of the new all-silicon Inner Tracker (ITk) for ATLAS for the HL-LHC, a series of system tests has been performed, to assess the performance of prototype planar and 3D pixel modules arranged into serial power chains mounted onto realistic mechanical structures. In this paper, the prototype loaded local supports and test infrastructure is described and the key results presented.

The planned MALTA3 DMAPS designed in the standard TowerJazz 180 nm imaging process will implement the numerous process modifications, as well as front-end changes in order to boost the charge collection efficiency after the targeted fluence of 1 × 10¹⁵ 1 MeV n_eq/cm². The effectiveness of these changes have been demonstrated with recent measurements of the full size MALTA2 chip. With the original MALTA concept being fully asynchronous, a small-scale MiniMALTA demonstrator chip has been developed with the intention of bridging the gap between the asynchronous pixel matrix, and the synchronous DAQ. This readout architecture will serve as a baseline for MALTA3, with focus on improved timing performance. The synchronization memory has been upgraded to allow clock speeds of up to 1.28 GHz, with the goal of achieving a sub-nanosecond on-chip timing resolution. The subsequent digital readout chain has been modified and will be discussed in the context of the overall sensor architecture.

We present the design and the performance of MUX64, a 64-to-1 analogue multiplexer ASIC for the ATLAS High Granularity Timing Detector (HGTD). The MUX64 transmits one of its 64 inputs selected by six address lines for the voltages or temperatures being monitored to an lpGBT ADC channel. The prototype ASICs fabricated in TSMC 130 nm CMOS technology were prepared in wire-bonding and QFN88 packaging format. A total of 280 chips was examined for functionality and quality assurance. The accelerated aging test conducted at 85 °C shows negligible degradation over 16 days.

The MALTA family of Depleted Monolithic Active Pixel Sensor (DMAPS) produced in Tower 180 nm CMOS technology targets radiation hard applications for the HL-LHC and beyond. Several process modifications and front-end improvements have resulted in radiation hardness up to 2 × 10¹⁵ 1 MeV n_eq/cm² and time resolution below 2 ns, with uniform charge collection efficiency across the pixel of size 36.4 × 36.4 μm² with a 3 μm² electrode size. The MALTA2 demonstrator produced in 2021 on high-resistivity epitaxial silicon and on Czochralski substrates implements a new cascoded front-end that reduces the RTS noise and has a higher gain. This contribution shows results from MALTA2 on timing resolution at the nanosecond level from the CERN SPS test-beam campaign of 2021.

In this article, we present a front-end amplifier that is equipped with a precise, fast, and automated reset circuit responsible for two actions: restoring the charge-sensitive amplifier output voltage from a pulse level to baseline, and the analog-to-digital conversion of the pulse amplitude. Importantly, the circuit is self-clocking, which allows to take advantage of the modern submicrometer CMOS process, and thus speed-up the reset and conversion phases. Thanks to the proposed approach, the fast clock signal distribution and an independent analog-to-digital converter per channel are not required, saving both the power consumption and the silicon area. The presented circuitry was adopted into 100-pixel-shaped recording channels and sent for fabrication in the CMOS 28 nm process.

The electron density close to the extraction grids and the co-extracted electrons represent a crucial issue when operating negative ion sources for fusion reactors. An excessive electron density in the plasma expansion region can indeed inhibit the negative ion production and introduce potentially harmful electrons in the accelerator. Among the set of plasma and beam diagnostics proposed for SPIDER upgrade, a heterodyne microwave (mw) interferometer at 100 GHz is currently being explored as a possibility to measure electron density in the plasma extraction region. The major issue in applying this technique in SPIDER is the poor accessibility of the probing microwave beam through the source metal walls and the long distance of 4 m at which mw modules should be located outside the vacuum vessel. Numerical investigations in a full-scale geometry showed that the power transmitted through the plasma source apertures was above the signal-to-noise ratio threshold for the microwave module sensitivity. An experimental proof-of-principle of the setup to assess the possibility of signal phase detection was then performed. The microwave system was tested on an experimental full-scale test-bench mimicking SPIDER viewports accessibility constraints, including the presence of a SPIDER-like plasma. The outcome of first tests revealed that, despite the geometrical constraints, in certain conditions, the phase detection, and, therefore, electron density measurements are possible. The main issue arises from decoupling the one-pass signal from spurious multipaths generated by mw beam reflections, requiring signal cross correlation analysis. These preliminary tests demonstrate that despite the 4 m distance between the mw modules and the presence of metal walls, plasma density measurement is possible when the 80 mm diameter ports are available. In this contribution, we discuss the numerical simulations, the preliminary experimental tests and suggest design upgrades of the interferometric setup to enhance signal transmission.

Hybrid pixel detectors require a reliable and cost-effective interconnect technology adapted to the pitch and die sizes of the respective applications. During the ASIC and sensor R&D phase, especially for small-scale applications, such interconnect technologies need to be suitable for the assembly of single dies, typically available from Multi-Project-Wafer submissions. Within the CERN EP R&D programme and the AIDAinnova collaboration, innovative hybridisation concepts targeting vertex-detector applications at future colliders are under development. Recent results of two novel interconnect methods for pixel pitches of 25 µm and 55 µm are presented in this contribution — an industrial fine-pitch SnAg solder bump-bonding process adapted to single-die processing using support wafers, as well as a newly developed in-house single-die interconnection process based on Anisotropic Conductive Film (ACF). The fine-pitch bump-bonding process is qualified with hybrid assemblies from a recent bonding campaign at Frauenhofer IZM. Individual CLICpix2 ASICs with 25 µm pixel pitch were bump-bonded to active-edge silicon sensors with thicknesses ranging from 50 µm to 130 µm. The device characterisation was conducted in the laboratory as well as during a beam test campaign at the CERN SPS beam-line, demonstrating an interconnect yield of about 99.7%. The ACF interconnect technology replaces the solder bumps by conductive micro-particles embedded in an epoxy film. The electro-mechanical connection between the sensor and ASIC is achieved via thermocompression of the ACF using a flip-chip device bonder. The required pixel pad topology is achieved with an in-house Electroless Nickel Immersion Gold (ENIG) plating process. This newly developed ACF hybridisation process is first qualified with the Timepix3 ASICs and sensors with 55 µm pixel pitch. The technology can be also used for ASIC-PCB/FPC integration, replacing wire bonding or large-pitch solder bumping techniques. This contribution introduces the two interconnect processes and presents preliminary hybridisation results with CLICpix2 and Timepix3 sensors and ASICs.

Silicon carbide detectors represent an alternative to diamond detectors for fast neutron detection in harsh environments, especially fusion plasmas. Previous studies on thin prototypes (either 10 μm or 100 μm thick) suggested that thicker active volumes might be better suited for spectroscopy measurements, due to the higher chance of retaining the neutron interaction products inside the active volume. Therefore, in this work two 250 μm SiC prototypes are tested with alpha particles following the same process conducted in the past for thinner prototypes. A stable detection is demonstrated, along an energy resolution that, if projected to DT neutrons, could become the lowest achieved so far with a SiC detector (1.3%). Some difficulties in reaching a full depletion are highlighted, as long as perspectives of a partial polarization operation of the detectors.

We present a model of the ionization efficiency, or quenching factor, for low-energy nuclear recoils, based on a solution to Lindhard integral equation with binding energy and apply it to the calculation of the relative scintillation efficiency and charge yield for nuclear recoils in noble liquid detectors. The quenching model incorporates a constant average binding energy together with an electronic stopping power proportional to the ion velocity, and is an essential input in an analysis of charge recombination processes to predict the ionization and scintillation yields. Our results are comparable to NEST simulations of LXe and LAr and are in good agreement with available data. These studies are relevant to current and future experiments using noble liquids as targets for neutrino physics and the direct searches for dark matter.

This paper presents the design and test results of a Gigabit Cable Receiver ASIC called GBCR for the HL-LHC upgrade of the ATLAS Inner Tracker (ITk) pixel detector. Three prototypes (GBCR1, GBCR2, and GBCR3) have been designed in the CERN-identified 65 nm CMOS technology. GBCR receives seven (GBCR2) or six (GBCR3) channels (RX) each at 1.28 Gbps from the front-end readout chip RD53B via flex cables up to 1 meter and Twinax cables up to 5 meters and sends the equalized and retimed signals to lpGBT. Both GBCR2 and GBCR3 ASICs have two transmitting channels (TX) that pre-emphasize the signals from lpGBT before sending them to RD53B through the same cables. No Single-Event Upset (SEU) is observed in any tested channels of GBCR2 in a 400 MeV proton beam. The extrapolated bit error rate for the future HL-LHC application is below 8 × 10⁻¹⁶, significantly below the specified BER criterion. GBCR3 is designed to improve the immunity to single-event-upset by applying the Triple Modular Redundancy (TMR) technology to all RX channels. The retimed signals from GBCR3 have less total jitter than those from GBCR2 (35 ps versus 79 ps). Each receiver channel of GBCR3 consumes 75% more power than that of GBCR2.

Silicon photomultipliers (SiPMs) are emerging as the photodetector technology to be used in upcoming noble liquid experiments. Newly developed SiPMs sensitive to vacuum ultraviolet (VUV) light will be directly used for the readout of scintillation photons (λ = 175 nm) from liquid xenon in future tonne-scale experiments, such as nEXO, searching for neutrinoless double beta decay in ¹³⁶Xe. In this research project, VUV-SiPMs from two different vendors are characterized using current–voltage (IV) and pulse-level measurements performed at TRIUMF, from room temperature to liquid xenon temperature. These data are analysed to extract the SiPM's features such as breakdown voltage, gain, crosstalk, afterpulsing and dark noise rates. The IV and pulse-level results are compared. A method is proposed for rapid quality control of large numbers of SiPM using IV measurements.

The Versatile Link⁺ project targeting the Phase 2 HL-LHC detector upgrades is entering the production phase. After several years of prototyping, the industrialisation of the Versatile Link⁺ Transceiver (VTRx⁺) was launched in 2021 and the production is scheduled to start in 2022. We describe the extensive qualification effort carried out and the quality assurance procedures put in place to monitor the manufacturing quality. We summarise the experience of the industrialisation and we present the plans for the production.

Future upgrades of the CERN Experiments and Accelerators require optical links capable of handling the large data volume generated in particle detectors and beam position (BPMs) sensors. Silicon Photonics optical transceivers are a promising candidate to process the required data rate as well as efficiently operate in the harsh radiation environment. We present the experimental characterisation of silicon modulators together with demonstration of optical transmitters based on custom designed Silicon Photonics integrated circuits.

In the framework of the ATLAS experiment's Phase-II Upgrade at the High-Luminosity Large Hadron Collider (HL-LHC), new and improved trigger hardware and algorithms will be implemented onto a single-level, 10 μs-latency architecture. The Global Trigger is a new subsystem which will bring event-filter capabilities by performing offline-like algorithms on full-granularity calorimeter data. The implementation of the functionality is firmware-focused and composed of several processing nodes, which are hosted on identical hardware, made up of an Advanced Telecommunications Computing Architecture (ATCA) front board, called Global Common Module (GCM), and a rear transition module (RTM), called Generic RTM (GRM). The GRM, which was developed to mitigate the risks deriving from the complex design and power management of the GCM, features an advanced Xilinx Versal Prime system-on-chip and can handle communication with the GCM and Front-End Link eXchange (FELIX) subsystem and trigger processors through 124 25.8 Gb/s transceiver links, for readout and control. Additionally, the GRM mounts a Low-Power GigaBit Transceiver (lpGBT) chip which enables emulation of the detector front-ends for integration tests. This paper presents the GRM hardware design and its testing.

The ATLAS experiment is constructing new all-silicon inner tracking system for HL-LHC. The strip detectors cover the radial extent of 40 to 100 cm. A new approach is adopted to use p-type silicon material, making the readout in n⁺-strips, so-called n⁺-in-p sensors. This allows for enhanced radiation tolerance against an order of magnitude higher particle fluence compared to the LHC. To cope with varying hit rates and occupancies as a function of radial distance, there are two barrel sensor types, the short strips (SS) for the inner 2 and the long strips (LS) for the outer 2 barrel cylinders, respectively. The barrel sensors exhibit a square, 9.8 × 9.8 cm², geometry, the largest possible sensor area from a 6-inch wafer. The strips are laid out in parallel with a strip pitch of 75.5 μm and 4 or 2 rows of strip segments. The strips are AC-coupled and biased via polysilicon resistors. The endcap sensors employ a "stereo-annulus" geometry exhibiting a skewed-trapezoid shapes with circular edges. They are designed in 6 unique shapes, R0 to R5, corresponding to progressively increasing radial extents and which allows them to fit within the petal geometry and the 6-inch wafer maximally. The strips are in fan-out geometry with an in-built rotation angle, with a mean pitch of approximately 75 μm and 4 or 2 rows of strip segments. The eight sensor types are labeled as ATLAS18xx where xx stands for SS, LS, and R0 to R5. According to the mechanical and electrical specifications, CAD files for wafer processing were laid out, following the successful designs of prototype barrel and endcap sensors, together with a number of optimizations. A pre-production was carried out prior to the full production of the wafers. The quality of the sensors is reviewed and judged excellent through the test results carried out by vendor. These sensors are used for establishing acceptance procedures and to evaluate their performance in the ATLAS collaboration, and subsequently for pre-production of strip modules and stave and petal structures.

Negative ions compact cyclotrons serve many applications and are known to be effective due to their simple and efficient extraction as well as the large circulating currents without the requirement of separated turns. TR30s are compact cyclotrons that have continued to experience impressive technological advances over the last few decades, driven primarily by medical isotope production needs. Their space charge limits are in the range of 1 to 2 mA, and we explored the combination of our machines' age and the challenges of maintaining their performances. Certain subsystems are detailed with specific examples from more than 30 years of around-the-clock, quasi continuous operations with TR30 cyclotrons. The subsystems' failures and their part in the overall downtime will be presented.

A summary of numerical modeling capabilities regarding high power cyclotrons and fixed field alternating gradient machines is presented. This paper focuses on techniques made available by the OPAL simulation code.

For this issue, papers on the topic of cyclotron beam physics have been solicited and chosen to highlight the main areas both of historic interest and of active research. I take the opportunity to outline the differences and similarities between cyclotron dynamics as compared to other accelerator types. As well, I try to introduce the major areas of interest, referring to papers in this issue, as appropriate.

This is a general information article of the ICFA Beam Dynamics Newsletter No. 84. It contains two forewords from the Editor-in-Chief and the issue editor, a workshop and conference report section, a recent Ph.D. thesis section, a forthcoming beam dynamics events section, and a section of announcements from the beam dynamics panel.

Precision measurements and new physics searches require massive computation in high energy physics experiments. Supercomputer remains one of the most powerful computing resources in various areas. Taking the BESIII experiment as an illustration, we deploy the offline software BOSS into the top-tier supercomputer "Tianhe-II" with the help of Singularity. With very limited internet connection bandwidth and without root privilege, we synchronize and maintain the simulation software up to date through CVMFS successfully, and an acceleration rate in a comparison of HPC and HTC is realized for the same large-scale task. We solve two problems of the real-time internet connection and the conflict of loading locker by a deployment of a squid server and using fuse in memory in each computing node. We provide a MPI python interface for high throughput (HT) parallel computation in Tianhe-II. Meanwhile, the program to deal with data output is also specially aligned so that there is no queue issue in the input/output (I/O) task. The acceleration rate in simulation reaches 80%, as we have done the simulation tests up to 15K processes in parallel.

The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multipurpose underground liquid scintillator detector, was proposed for the determination of the neutrino mass hierarchy as primary physics goal. The central detector will be submerged in a water Cherenkov detector to lower the background from the environment and cosmic muons. Radon is one of the primary background sources. Nitrogen will be used in several sub-systems, and a highly sensitive radon detector has to be developed to measure its radon concentration. A system has been developed based on ²²²Rn enrichment of activated carbon and ²²²Rn detection based on the electrostatic collection. This paper presents the detail of a μBq/m³ level ²²²Rn concentration measurement system and gives detailed information about how the adsorption coefficient was measured and how the temperature, flow rate, and ²²²Rn concentration affect the adsorption coefficient.

In the field of radiation detection in microdosimetry, the Tissue Equivalent Proportional Counters (TEPCs) are the key detector options in determining the radiation quality. In this paper, two different structures of TEPCs were introduced, and their electric field uniformity and angular dependence were disscussed. A planar cascaded GEM TEPC with sealed chamber was developed in the laboratory and the general materials used in the detector were tested for outgassing characteristics. The experimental results showed that the polyether ether ketone (PEEK) had the lowest outgassing rate among all tested materials and were selected as the main assembly materials of the TEPC detector. The ²⁴¹Am was used as the built-in radioactive source for detector calibration, and the detector gain characteristics were studied. The long-term operating stability was tested at working pressure of 54.72 kPa, with a gain consistency of better than 97.8% over 7 days (168 hours) and relative gain variation less than 1% over 4 days (96 hours).