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We study single-image super-resolution algorithms for photons at collider experiments based on generative adversarial networks. We treat the energy depositions of simulated electromagnetic showers of photons and neutral-pion decays in a toy electromagnetic calorimeter as 2D images and we train super-resolution networks to generate images with an artificially increased resolution by a factor of four in each dimension. The generated images are able to reproduce features of the electromagnetic showers that are not obvious from the images at nominal resolution. Using the artificially-enhanced images for the reconstruction of shower-shape variables and of the position of the shower center results in significant improvements. We additionally investigate the utilization of the generated images as a pre-processing step for deep-learning photon-identification algorithms and observe improvements in the case of training samples of small size. [ABSTRACT FROM AUTHOR]

Charged particle beams driven to ultra-high dose rates (UHDRs) have been shown to offer potential benefits for future clinical applications, particularly in the reduction of normal-tissue toxicity. Studies of the so-called FLASH effect have shown promise, generating huge interest in high dose rate radiation studies. With laser-driven proton beams, where the duration of the proton burst delivered to a sample can be as short as hundreds of picoseconds, the instantaneous dose rates are several orders of magnitude higher than those used for conventional radiotherapy. The dosimetry of these beam modalities is not trivial, with conventional active detectors, such as ionisation chambers, experiencing saturation effects making them unusable at the extremely high dose rates. Calorimeters, measuring the radiation-induced temperature rise in an absorber, offer an ideal candidate for the dosimetry of UHDR beams. However, their application in the measurement of laser-driven UHDR beams has so far not been trialled, and their effective suitability to work with the quasi-instantaneous and inhomogeneous dose deposition patterns and the harsh environment of a laser-plasma experiment has not been tested. The measurement of the absorbed dose of laser-driven proton beams was conducted in a first-of-its-kind investigation, employing the VULCAN-PW laser system of the Central Laser Facility (CLF) at the Rutherford Appleton Laboratory (RAL), using a small-body portable graphite calorimeter (SPGC) developed at the National Physical Laboratory (NPL) and radiochromic films. A small number of shots were recorded, with the corresponding absorbed dose measurements resulting from the induced temperature rise. The effect of the electromagnetic pulse (EMP) generated during laser–target interaction was assessed on the system, showing no significant effects on the derived signal-to-noise ratio. These proof-of-principle tests highlight the ability of calorimetry techniques to measure the absorbed dose for laser-driven proton beams. [ABSTRACT FROM AUTHOR]

Objective. Proton therapy is highly sensitive to range uncertainties due to the nature of the dose deposition of charged particles. To ensure treatment quality, range verification methods can be used to verify that the individual spots in a pencil beam scanning treatment fraction match the treatment plan. This study introduces a novel metric for proton therapy quality control based on uncertainties in range verification of individual spots. Approach. We employ uncertainty-aware deep neural networks to predict the Bragg peak depth in an anthropomorphic phantom based on secondary charged particle detection in a silicon pixel telescope designed for proton computed tomography. The subsequently predicted Bragg peak positions, along with their uncertainties, are compared to the treatment plan, rejecting spots which are predicted to be outside the 95% confidence interval. The such-produced spot rejection rate presents a metric for the quality of the treatment fraction. Main results. The introduced spot rejection rate metric is shown to be well-defined for range predictors with well-calibrated uncertainties. Using this method, treatment errors in the form of lateral shifts can be detected down to 1 mm after around 1400 treated spots with spot intensities of 1 × 107 protons. The range verification model used in this metric predicts the Bragg peak depth to a mean absolute error of 1.107 ± 0.015 mm. Significance. Uncertainty-aware machine learning has potential applications in proton therapy quality control. This work presents the foundation for future developments in this area. [ABSTRACT FROM AUTHOR]

Background: Electron synchrotrons produce x‐ray beams with dose rates orders of magnitude greater than conventional x‐ray tubes and with beam sizes on the order of a few millimeters. These characteristics put severe challenges on current dosimeters to accurately realize absorbed dose or air kerma. Purpose: This work seeks to investigate the suitability of a novel aluminum‐based calorimeter to determine absorbed dose to water with an uncertainty significantly smaller than currently possible with conventional detectors. A lower uncertainty in the determination of absolute dose rate would impact both therapeutic applications of synchrotron‐produced x‐ray beams and research investigations. Methods: A vacuum‐based calorimeter prototype with an aluminum core was built, matching the beam profile of the 140 keV monochromatic x‐ray beam, produced by the Canadian Light Source Biomedical Imaging and Therapy beamline. The choice of material and overall calorimeter design was optimized using FEM thermal modeling software while Monte Carlo radiation transport simulations were used to model the impact of interactions of the radiation beam with the detector components. Results: Corrections for both the thermal conduction and radiation transport effects were of the order of 3% and the simplicity of the geometry, combined with the monochromatic nature of the incident x‐ray beam, meant that the uncertainty in each correction was ≤0.5%. The calorimeter performance was found to be repeatable over multiple irradiations of 1 Gy at the ± 0.6% level, and no systematic dependence on environmental effects or total dose was observed. Conclusion: The combined standard uncertainty in the determination of absorbed dose to aluminum was estimated to be 0.8%, indicating that absorbed dose to water, the ultimate quantity of interest, could be determined with an uncertainty on the order of 1%. This value is an improvement over current techniques used for synchrotron dosimetry and comparable with the state‐of‐the art for conventional kV x‐ray dosimetry. [ABSTRACT FROM AUTHOR]

The ALICE experiment at the LHC is designed to explore the hot and dense medium produced in heavy-ion collisions, the so-called quark–gluon plasma (QGP). Antineutron production is a poorly explored domain of high energy physics, although it is interesting in the context of hadrons decaying into antineutrons, the interaction of antineutrons with hadrons, and searching for bound states of antineutrons. We present a method for measuring antineutrons by the electromagnetic calorimeter PHOS of the ALICE experiment. An antineutron can be identified by the cluster shape and the energy deposition in the calorimeter, and its momentum can be reconstructed using the time-of-flight information. The proposed method was verified via the reconstruction of through decays and with an antineutron identified in the PHOS. [ABSTRACT FROM AUTHOR]

The LHCb Upgrade phase II conditions require a significant change of the detector systems including the electromagnetic calorimeter (ECAL), which must be capable to sustain high radiation doses in the innermost region and provide good time resolution. The central part of the ECAL will be substituted by spaghetti calorimeter (SPACAL). This paper presents the results of the first cast lead–polystyrene SPACAL prototypes studies performed at the CERN SPS and DESY test beam areas. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental studies conducted with the aim of determining the characteristics of the heat exchange of a dense layer of bulk material with surfaces and obtaining empirical dependences for average and local heat transfer coefficients during transverse flow through a dense layer of a submerged cylinder. Empirical dependences are valid in a wide range of changes in geometric and regime parameters within a satisfactory experimental error. The need for research in this area is due to the fact that most of the known literature data on heat exchange between dispersed material and the surface describes heat exchange with flows at a low concentration of dispersed material (dusty flows, gas suspension, fluidized beds). The heat exchange of a dense layer with a surface is devoted to a rather limited number of works carried out in the seventies and eighties, but even in these works there are contradictions not only of a quantitative, but also of a qualitative nature. In the presented work, the research was carried out on an experimental installation, made in the form of a rectangular vertical mine, in which, under the action of gravity, bulk material enters in the form of a dense layer. Determination of heat transfer coefficients was performed using the methods of stationary and regular thermal regimes. As a result of the generalization of experimental data, criterial dependences were obtained, which allow thermal calculation of tubular heat exchangers for heating (cooling) bulk materials moving in the form of a dense layer. The resulting dependencies are important for the chemical industry, at non-ferrous metallurgy enterprises, during heat treatment of materials and in other industries where there is a need to heat (cool) bulk materials in the relevant technological processes or for the purpose of heat utilization. [ABSTRACT FROM AUTHOR]

Objective. To report the use of a portable primary standard level graphite calorimeter for direct dose determination in clinical pencil beam scanning proton beams, which forms part of the recommendations of the proposed Institute of Physics and Engineering in Medicine (IPEM) Code of Practice (CoP) for proton therapy dosimetry. Approach. The primary standard proton calorimeter (PSPC) was developed at the National Physical Laboratory (NPL) and measurements were performed at four clinical proton therapy facilities that use pencil beam scanning for beam delivery. Correction factors for the presence of impurities and vacuum gaps were calculated and applied, as well as dose conversion factors to obtain dose to water. Measurements were performed in the middle of 10 × 10 × 10 cm3 homogeneous dose volumes, centred at 10.0, 15.0 and 25.0 g·cm−2 depth in water. The absorbed dose to water determined with the calorimeter was compared to the dose obtained using PTW Roos-type ionisation chambers calibrated in terms of absorbed dose to water in 60Co applying the recommendations in the IAEA TRS-398 CoP. Main results. The relative dose difference between the two protocols varied between 0.4% and 2.1% depending on the facility. The reported overall uncertainty in the determination of absorbed dose to water using the calorimeter is 0.9% (k = 1), which corresponds to a significant reduction of uncertainty in comparison with the TRS-398 CoP (currently with an uncertainty equal or larger than 2.0% (k = 1) for proton beams). Significance. The establishment of a purpose-built primary standard and associated CoP will considerably reduce the uncertainty of the absorbed dose to water determination and ensure improved accuracy and consistency in the dose delivered to patients treated with proton therapy and bring proton reference dosimetry uncertainty in line with megavoltage photon radiotherapy. [ABSTRACT FROM AUTHOR]

Cone calorimeters are widely used to assess heat release parameters and flammability of combustible materials, but their use is limited for applications where the global equivalence ratio (GER) exceeds one, because they can only replicate burning in open conditions. The standardisation of the controlled atmosphere cone calorimeter (CACC) in the ISO/TS 5660-5:2020 offers an opportunity to investigate the potential advantages and limitations of this apparatus. This paper presents a detailed review of existing studies conducted using the CACC. The review is aimed at examining the importance of atmospheric control for bench-scale experimental methods and the research-based development of key features of the apparatus. In addition, it highlights the research yet to be carried out to optimise the use of CACC as a tool in fire science. The effects of various design parameters are discussed including the method used for GER control, the chimney, the chamber, the gas inflow rate and others. Despite standardisation, it is concluded that there is limited consensus on optimal CACC control variables. A lack of consensus has led to significantly different testing conditions even where researchers use the same materials and have similar research objectives. The lack of best practice, particularly with regards to a gas sampling location and the method of GER control, motivates the need for further research so as to improve the value of data collected, reduce uncertainty and optimise CACC reproducibility. [ABSTRACT FROM AUTHOR]

Isothermal control is the most basic and crucial function in the principle of a reaction calorimeter system and affects the speed and validity of the calorimetric experiment. However, the complex and uncertain working conditions in different reaction processes pose a challenge to the adaptability of temperature control algorithms. Aiming at the problem, a heat transfer model of the system is first established for temperature control design. From the simulation results, a prediction model based on equivalent mechanism parameters is determined for the control. Then, an integrated model predictive control (MPC) strategy is presented. To reduce the influence on the temperature control caused by the mismatch of the prediction model, a set of online parameter identification and adjustment methods is proposed. Simulations of the MPC control were implemented to analyze the control's performance. Experiments were also carried out to verify the advantages of the proposed strategy over the proportional-integral-derivative algorithm and demonstrate the role and efficiency of online identification. This control strategy can be applied to other laboratory-scale instruments with tank reactors. [ABSTRACT FROM AUTHOR]

Using the small-x improved transverse momentum dependent factorization (ITMD), which, for a general two-to-two massless scattering can be proved within the color glass condensate (CGC) theory for transverse momenta of particles greater than the saturation scale, we provide predictions for isolated forward photon and jet production in proton-proton and proton-nucleus collisions within the planned ALICE FoCal detector acceptance. We study azimuthal correlations, p T spectra, as well as normalized ratios of proton-proton cross sections for different energies. The only TMD distribution needed for that process is the "dipole" TMD gluon distribution, which in our computations is based on HERA data and undergoes momentum space BK evolution equation with DGLAP corrections and Sudakov resummation. We conclude, that the process provides an excellent probe of the dipole TMD gluon distribution in saturation regime. [ABSTRACT FROM AUTHOR]

A calorimeter for measuring heats of detonation at Lawrence Livermore National Laboratory is described. A calibration precision of 0.2 % at the 95 % confidence interval (CI) is reported. Sources of uncertainty are discussed, including nonequivalent sources, which are those arising from differences between calibration and experimental tests. The systematic error due to nonequivalent sources is bounded to 0.19–0.22 % of the measured heat for a standard detonation test where the confinement material is gold. The recommendation is to correct for the systematic error by adding 0.19 % to the reported value and adding 0.03 % to the uncertainty. It is demonstrated that the precision of a detonation test is variable with testing duration because a source of uncertainty resides in the thermodynamic correction factor k6, which accounts for the contribution to heat by stirring; the generated power is additive and therefore highly impacted by total test time. The relative proportion also varies with the magnitude of heat release and sample size, adding variance to the weight of the error arising from the correction factor. A full error analysis based on the described sources of uncertainty is developed. The methodology is applied to a test series on neat 2,4,6‐triamino‐1,3,5‐ trinitrobenzene (TATB), demonstrating an ultimate precision of 0.7 % (single test) for materials testing and a relative standard deviation of 1.8 %. [ABSTRACT FROM AUTHOR]

CUPID-Mo is a cryogenic detector array designed to search for neutrinoless double-beta decay (0νββ) of 100Mo. It uses 20 scintillating 100Mo-enriched Li2MoO4 bolometers instrumented with Ge light detectors to perform active suppression of α backgrounds, drastically reducing the expected background in the 0νββ signal region. As a result, pileup events and small detector instabilities that mimic normal signals become non-negligible potential backgrounds. These types of events can in principle be eliminated based on their signal shapes, which are different from those of regular bolometric pulses. We show that a purely data-driven principal component analysis based approach is able to filter out these anomalous events, without the aid of detector response simulations.

This work evaluates the effects of the acidity of montmorillonites on the thermal degradation process and in the cone calorimeter parameters of an intumescent composite constituted by polypropylene, ammonium polyphosphate (APP) and pentaerythritol (PER). The cone calorimeter tests showed that the absence of moderate-strength acidic sites is related to the increase in the peak of heat release rate. The composites were burnt at different key-temperatures and the residues were submitted to Fourier transform infrared spectroscopy, Solid State Nuclear Magnetic Resonance Spectroscopy and to X-ray diffraction. The results showed that the addition of the clay minerals is important to preserve the char at higher temperatures (over 430 °C) and that an excess of Brønsted sites over the Lewis ones with moderate-strength could lead to the increase of the esterification reactions between PER and APP. Besides, the addition of the clay minerals did not affect the mechanical properties of the composites. [ABSTRACT FROM AUTHOR]

• The constant, single variable (valve lift dependent), and double variable (valve lift and piston position dependent) flow and force coefficients were compared in a reciprocating compressor. • The constant flow and force coefficients can estimate the cyclic performances accurately. • The single variable and double variable models predict the valve dynamics, and the in-cylinder pressure picks more accurately than the constant model. • A 3-D CFD analysis of the discharge flow field with realistic valve geometry was performed. Enhancing the mathematical models always have been a critical issue in every field, and the reciprocating compressors are not exceptional. Flow and force coefficients are two empirical factors that help to calculate the mass flow rate through the valve and gas force, respectively. These coefficients can be considered constant values or valve lift dependent. However, in the discharge process, the piston is close to the top dead center, which may affect the discharge flow field and, subsequently, the coefficients. These coefficients should be determined by experiments or numerical simulations such as computational fluid dynamics (CFD). Experiments are expensive, and the exact geometry may not always be available to perform the CFD analysis. Also, CFD analysis for various valve lifts and piston positions is computationally expensive. This study studied the effect of constant, single variable (valve lift dependent) and double variable (valve lift and piston position dependent) coefficients on compressor performance and discharge valve movement in three operating conditions. A mathematical model was developed for this purpose, and a 3-D CFD simulation was used to compute the coefficients. To validate the results, a strain gauge and a calorimeter were used as measurement tools. The single and double variable models captured the valve behavior, and pressure picks better than the constant model. However, the constant model estimated the indicated power, cooling capacity, and COP with good accuracy. In predicting the discharge losses, the double variable model was the most reliable among the others. [ABSTRACT FROM AUTHOR]

The incorporation of fly ash in polybutyl succinate (PBS) and polybutyl adipate terephtalate (PBAT) in the partial replacement of ammonium polyphosphate and/or melamine polyphosphate is evaluated in the present work. Furthermore, the influence of the surface modification of fly ash with two silanes and titanate coupling agents was also studied. Cone calorimeter experiments, pyrolysis combustion flow calorimeters (PCFCs), and UL94V tests were used to assess the fire performance of the composites. Scanning electronic microscopy, X-microanalysis, and X-ray diffractometry analysis were carried out on cone calorimeter residues in order to access the fire-retardant mode of action. The formation of new components due to the presence of fly ash was highlighted by X-ray diffractometry, indicating the synergistic effects between the flame-retardant system and fly ash. The X-microanalysis results showed that the main fraction of initial phosphorous is present in the cone calorimeter residue, indicating that the proposed system acts in a condensed phase. [ABSTRACT FROM AUTHOR]

Recently, with the extensive use of lithium-ion batteries (LIBs) in particular important areas such as energy storage devices, electric vehicles (EVs), and aerospace, the accompanying fire safety issues are also emerging and need to be taken into account seriously. Here, a series of experiments for LIB packs with five kinds of pack sizes (1 × 1, 1 × 2, 2 × 2, 2 × 3, 3 × 3) and three types of different state of charge (SOC) (100%, 50%, and 0%) were carried out using a cone calorimeter. Relevant fire parameters such as heat release rate (HRR), mass loss, and concentrations of CO, CO2, and O2 were investigated. Remarkably similar combustion phenomena with intermittent jets were observed for LIB packs with 50% SOC and 100% SOC. The total mass loss (TML) and the peak value of HRR (pHRR) showed a similar positive correlation relationship of a power function with the surface area of the exposed heat source. For battery packs with 100% SOC, the pHRR of 3 × 3 cell module even increased by about 8 times to 12 kW. The content of toxic gas CO was evaluated by determining fractional effective dose (FED). It could be concluded that when the pack size was smaller than 2 × 3, the FED was below 1 for battery packs with 50% SOC and 100% SOC. This study can help predict the development patterns and fire risk of more large-scale battery fires and further diminish the thermal runaway (TR) hazard during an accident. [ABSTRACT FROM AUTHOR]

We report on an experiment conducted at the ESR storage ring aiming at the study of the X-ray emission of Xe 54 + ions colliding with Xe atoms at a beam energy of 50 MeV/u. The radiation resulting from the ion–atom interaction was observed using a high-resolution spectrometer based on metallic–magnetic calorimeter technology. In order to benchmark the capabilities of these detectors for high-precision atomic physics experiments, we identified several transitions from H-like and He-like xenon and determined their energies. Furthermore, the 1s-Lamb shift in Xe 53 + was estimated using the measured line energies. The results are compared with previous experimental studies and theoretical predictions. [ABSTRACT FROM AUTHOR]

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During a failure event, electrochemical cells can exhibit such characteristics as extreme high temperatures, deflagration, fire, venting of electrolyte and rapid uncontrolled disassembly. The cell's characteristics prior to, during, and after a destructive event are important in developing preventive and mitigating hazard steps. A novel measuring system based on isothermal calorimetry has been developed and utilized to further understand the worst-case event produced by large format electrochemical cells. This system allows for the containment of the reaction and its products while measuring the pressure and release rate of the gaseous product, as well as a complete thermal profile of the reaction. This paper provides a description of the calorimeter, calibration test results on its performance, test results, and empirical model from a selection of cells tested. The cells utilized in this developmental testing were Lithium Iron Phosphate and Lithium Cobalt Oxide cells ranging from 6 to 38 Ampere hour capacities and approximately 40 mm diameter, 170 mm height, and 0.35 kg each. This analytical system allows for a wide range of cells, chemistries, failure mechanisms and testing environments for lithium-ion cells, static or under load. Empirical models developed from this flexible and adaptive system will enable researchers to compare larger samples across material property boundaries to better predict the outcome of destructive chemical reactions. [ABSTRACT FROM AUTHOR]

The Future Circular Collider FCC-ee aims at unprecedented luminosities to be obtained with the crab-waist collision scheme. In this paper we describe the mechanical model of the interaction region layout including its assembly procedure. After a discussion on the requirements and constraints, we present the engineered design of the vacuum chamber with the cooling system, the bellows, the vertex and outer tracker detectors and their integration in a carbon-fibre lightweight support structure that will support also the luminosity calorimeter. [ABSTRACT FROM AUTHOR]

A 57 Fe nucleus in the solar core could emit a 14.4-keV monochromatic axion through the M1 transition if a hypothetical elementary particle, axion, exists to solve the strong CP problem. Transition edge sensor (TES) X-ray microcalorimeters can detect such axions very efficiently if they are again converted into photons by a 57 Fe absorber. We have designed and produced a dedicated TES array with 57 Fe absorbers for the solar axion search. The iron absorber is set next to the TES, keeping a certain distance to reduce the iron-magnetization effect on the spectroscopic performance. A gold thermal transfer strap connects them. A sample pixel irradiated from a 55 Fe source detected 698 pulses. In contrast to thermal simulations, we consider that the pulses include either events produced in an iron absorber or gold strap at a fraction dependent on the absorption rate of each material. Furthermore, photons deposited on the iron absorber are detected through the strap as intended. The identification of all events still needs to be completed. However, we successfully operated the TES with the unique design under iron magnetization for the first time. [ABSTRACT FROM AUTHOR]

The PreProcessor of the ATLAS Level-1 Calorimeter Trigger prepares the analogue trigger signals sent from the ATLAS calorimeters by digitising, synchronising, and calibrating them to reconstruct transverse energy deposits, which are then used in further processing to identify event features. During the first long shutdown of the LHC from 2013 to 2014, the central components of the PreProcessor, the Multichip Modules, were replaced by upgraded versions that feature modern ADC and FPGA technology to ensure optimal performance in the high pile-up environment of LHC Run 2. This paper describes the features of the new Multichip Modules along with the improvements to the signal processing achieved.

We describe a method used to calibrate the position- and time-dependent response of the MicroBooNE liquid argon time projection chamber anode wires to ionization particle energy loss. The method makes use of crossing cosmic-ray muons to partially correct anode wire signals for multiple effects as a function of time and position, including cross-connected TPC wires, space charge effects, electron attachment to impurities, diffusion, and recombination. The overall energy scale is then determined using fully-contained beam-induced muons originating and stopping in the active region of the detector. Using this method, we obtain an absolute energy scale uncertainty of 2% in data. We use stopping protons to further refine the relation between the measured charge and the energy loss for highly-ionizing particles. This data-driven detector calibration improves both the measurement of total deposited energy and particle identification based on energy loss per unit length as a function of residual range. As an example, the proton selection efficiency is increased by 2% after detector calibration.

We report on the use of a kinetic-inductance traveling-wave parametric amplifier (KITWPA) as the first amplifier in the readout chain of a microwave superconducting quantum interference device (SQUID) multiplexer (μmux). This μmux is designed to multiplex signals from arrays of low temperature detectors, such as superconducting transition-edge sensor microcalorimeters. When modulated with a periodic flux-ramp to linearize the SQUID response, the flux noise improves, on average, from 1.6 μ Φ 0 / Hz with the KITWPA off to 0.77 μ Φ 0 / Hz with the KITWPA on. When statically biasing the μmux to the maximally flux-sensitive point, the flux noise drops from 0.45 μ Φ 0 / Hz to 0.2 μ Φ 0 / Hz . We validate this new readout scheme by coupling a transition-edge sensor microcalorimeter to the μmux and detecting background radiation. The combination of μmux and KITWPA provides a variety of new capabilities including improved detector sensitivity and more efficient bandwidth utilization. [ABSTRACT FROM AUTHOR]

Prediction of flammability characteristics of materials is possible via molar group contribution calculations. However, in most industries raw material composition is unknown and micro combustion calorimeter (MCC) is applied for measuring heat release rate (HRR) and calculates flammability characteristics. This work predicts HRR and flammability characteristics for complex formulations based on HRR from a reduced number of the individual constituents, all with unknown chemical composition. Water-based paints (> 15 components) with and without chemical interaction during thermal decomposition were predicted via linear combinations of component HRR and validated against experimental MCC data. Prediction of HRR and flammability characteristics was successful, and the obvious breakdown for reactive mixtures was confirmed. These results can be utilized as screening tool for flammability characteristics and identity component interaction in mixtures—which considerably enhances the strength of MCC in development of new materials. [ABSTRACT FROM AUTHOR]

In vivo determination of the skin's thermal properties is of growing interest. Several types of sensors are being designed and tested. In this field, we have developed a skin calorimeter for the determination of the heat flow, the heat capacity and the thermal resistance of the skin. The calorimeter calibration consists of the determination of the parameters of the model we have chosen to represent the behavior of the device. This model considers the heat capacity and the thermal resistance of the skin, which depend on the case (body zone, subject, physical state, etc.) and also have a strong time dependence. Therefore, this work includes a validation study with reference materials. Finally, it is concluded that the heat capacity determined is a function of the thermal penetration depth of the measurement characteristics. In the case of high thermal conductivity materials in which the thermal penetration is nearly total, the heat capacity obtained coincides with that of the reference material sample. [ABSTRACT FROM AUTHOR]

To study the oxidation characteristics of coal under different conditions of mixed particle sizes, a C80 microcalorimeter and ESR spectrometer were used to study the heat release characteristics and laws of free radical parameter changes for coal samples with different mixed particle sizes. Research indicates that a smaller average particle size in the mixed coal sample results in stronger low-temperature oxidation and greater heat release from coal and a smaller apparent activation energy and initial heat release temperature. The concentration of free radicals in coals increases with decreasing average particle size in the mixed coal samples. When the average particle size in the mixed coal sample increased from 0.09 mm to 0.246 mm, the cumulative heat release of the GJW coal sample and the YHP coal sample decreased by 36.67% and 20.13%, and the free radical concentration decreased by 4.34 × 1017/g and 3.66 × 1017/g. In addition, In the mixed coal samples, the mean particle size mutation value was 0.126, which makes the heat release characteristics of coal at this particle size opposite to the overall trend. Further analysis established the relationship model between the heat of different mixed particle sizes and the free radical concentration of different mixed particle sizes as follows: y = ax3+ bx2+ cx+d. [ABSTRACT FROM AUTHOR]

Electrical cables must fulfil the Construction Product Regulation (CPR) by testing them according to EN 50,399. Nevertheless, an unfordable trial and error procedure could stem from the definition of new cables. To achieve a better understanding of fire behavior of cables, researchers have been using techniques such as bench and reduced scale tests and computational fire models result in a way to minimize trial and error process. The present work proposes the combination of bench scale tests, using cone calorimeters and fire simulation modeling. In a first step, the thermal characterization of the cable parts is carried out, and then, in a second step, use these data to model complete cable samples in cone calorimeter tests. The simulations are compared with experimental data of two already rated cables. This process is intended to discard erroneous configurations, which display in bench scale signs of misbehavior compared with rated cables. This would avoid the manufacture of the complete cable if the results do not fulfill the requirements, and eventually, proceed to its production and test in full-scale when they do. This work has been carried out with two multi-core cables and the materials they were made of, and the results showed: a) the inverse modeling process to characterize materials parts obtained a fairly accurate approach, with small inaccuracies in the peaks of the curves; b) two simulation models (simple and detailed) were able to reproduce in general terms the heat release rate curve; however, they released more energy than experimental tests and some discrepancies in the peaks were observed. Despite its simplicity, simple model obtained results fairly close to the experimental curves and took less time to simulate. [ABSTRACT FROM AUTHOR]

While awaiting direct velocity measurements of gas motions in the hot intracluster medium, we rely on indirect probes, including gas perturbations in galaxy clusters. Using a sample of ∼80 clusters in different dynamic states from Omega500 cosmological simulations, we examine scaling relations between the fluctuation amplitudes of gas density, δρ/ρ, pressure, δ P / P , X-ray surface brightness, Sunyaev–Zel'dovich (SZ) y-parameter, and the characteristic Mach number of gas motions, M 1d. In relaxed clusters, accounting for halo ellipticities reduces δρ/ρ or δ P / P by a factor of up to 2 within r 500 c . We confirm a strong linear correlation between δρ/ρ (or δ P / P) and M 1d in relaxed clusters, with the proportionality coefficient η ≈ 1. For unrelaxed clusters, the correlation is less strong and has a larger η ≈ 1.3 ± 0.5 (1.5 ± 0.5) for δρ/ρ (δ P / P). Examination of the M 1d − δρ/ρ relation shows that it is almost linear for relaxed clusters, while for the unrelaxed ones, it is closer to |$\delta \rho /\rho \propto M_{\rm 1d}^2$|⁠. In agreement with previous studies, we observe a strong correlation of M 1d with radius. Correcting for these correlations leaves a residual scatter in M 1d of ∼4(7) per cent for relaxed (perturbed) clusters. Hydrostatic mass bias correlates with M 1d as strongly as with δρ/ρ in relaxed clusters. The residual scatters after correcting for derived trends is ∼6−7 per cent. These predictions can be verified with existing X-ray and SZ observations of galaxy clusters combined with forthcoming velocity measurements with X-ray microcalorimeters. [ABSTRACT FROM AUTHOR]

Smoke is an important component of wildfires. Specifying the combustion process of different materials allows scientists to better prevent and adopt public health measures. This experimental study contributes to a better characterisation of the smoke emitted by two types of decking, wood and thermoplastic, commonly used in terraces. Emission factors were characterised using a cone calorimeter for different incident fluxes ranging from 10 to 50 kW/m2. The study showed that compared to wooden (pine) decking, thermoplastic (polypropylene) decking produces more gases and aerosols, less VOCs, but with a chemical composition that is more carcinogenic. [ABSTRACT FROM AUTHOR]

Whole‐room indirect calorimeters (WRICs) provide accurate instruments for the measurement of respiratory exchange, energy expenditure, and macronutrient oxidation. Here, we aimed to determine the validity and reproducibility of a 7500 L WRIC for the measurement of ventilation rates and resting metabolic rate (RMR). Technical validation was performed with propane combustion tests (n = 10) whereas biological reproducibility was tested in healthy subjects (13 women, 6 men, mean ± SD age 39.6 ± 15.3) in two 60 min measurements separated by 24 h. Subjects followed a run‐in protocol prior to measurements. The coefficient of variation (CV) and intraclass correlation coefficient (ICC) were calculated for ventilation rates of O2 (VO2), CO2 (VCO2), the respiratory quotient (RQ; VCO2/VO2), and RMR. Technical validation showed good validity with CVs ranging from 0.67% for VO2 to 1.00% for energy expenditure. For biological reproducibility, CVs were 2.89% for VO2; 2.67% for VCO2; 1.95% for RQ; and 2.68% for RMR. With the exception of RQ (74%), ICCs were excellent for VO2 (94%), VCO2 (96%) and RMR (95%). Excluding participants that deviated from the run‐in protocol did not alter results. In conclusion, the 7500 L WRIC is technically valid and reproducible for ventilation rates and RMR. [ABSTRACT FROM AUTHOR]

The time and energy resolutions were measured for four prototypes of the PHOS electromagnetic calorimeter for the ALICE experiment at the Large Hadron Collider at CERN. Each prototype was made up of nine identical detection elements assembled as a 3 × 3 array. The detection element was based on a lead tungstate (PbWO4) scintillating crystal with a length of 180 mm and a cross section of 22 × 22 mm2, which was viewed from its end face by a photodetector. Avalanche photodiodes and silicon photomultipliers with different active areas (Hamamatsu, Japan) were used as photodetectors. The measurements were made with the electron component of secondary particle beams of the PS proton synchrotron at CERN in the momentum range of 1−10 GeV/c at a temperature of 17.5°C. [ABSTRACT FROM AUTHOR]

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Thermite films are typical energetic materials (EMs) and have great value in initiating explosive devices. However, research in thermite film preparation is far behind that of research in thermite powders. Electrophoretic deposition (EPD) is an emerging, rapid coating method for film fabrication, including of energetic composite films. In this work, a polytetrafluoroethylene (PTFE)/Al/CuO organic-inorganic hybrid energetic film was successfully obtained using the above method for the first time. The addition of lithocholic acid as a surfactant into the electroplating suspension enabled PTFE to be charged. The combustion and energy release were analyzed by means of a high-speed camera and differential scanning calorimetery (DSC). It was found that the combustion process and energy release of PTFE/Al/CuO were much better than that of Al/CuO. The main reason for the excellent combustion performance of the hybrid PTFE/Al/CuO system was that the oxidability of PTFE accelerated the redox reaction between Al and CuO. The prepared PTFE/Al/CuO film was also employed as ignition material to fire a BeKNO3 explosive successfully, indicating considerable potential for use as an ignition material in micro-ignitors. This study sheds light on the preparation of fluoropolymer-containing organic-inorganic hybrid energetic films by one-step electrophoretic deposition. [ABSTRACT FROM AUTHOR]

Continuous flow calorimeters are a promising tool in process development and safety engineering, especially for flow chemistry applications to characterize the heat release and kinetic parameters of rapid chemical reactions. In this study, the digital accompaniment of an isoperibolic flow calorimeter for characterization of exothermic reactions is presented. To support experimental planning and evaluation, computational fluid dynamic simulations are carried out for single-phase flow in the microreactor. The residence time distribution is obtained and used for estimation of conversion and temperature profiles along the microreactor channel. This leads to an integration of CFD simulations into the calorimeter's software-guided workflow reducing the experimental effort regarding the determination of thermokinetic data. The approach is tested for a highly exothermic test reaction, which provides further hints for future investigations. Article highlights: • Estimation of conversion and temperature profiles within a microscale calorimeter • Combination of CFD simulations and reactor performance estimation • Approach was tested for highly oxidation of sodium thiosulfate • Estimated conversion and temperature profiles are in good agreement with experimental data Graphical abstract [ABSTRACT FROM AUTHOR]

In this work, the flame retardancy influences of colemanite and boron oxide are investigated n huntite-hydromagnesite (HH) containing plasticized poly (lactic acid) (PLA) biocomposites. The composites are characterized using limiting oxygen index (LOI), horizontal (UL 94 HB) and vertical (UL-94 V) burning tests, mass loss calorimeter (MLC), and thermogravimetric analysis (TGA). The addition of colemanite causes enhanced fire retardancy performance with higher UL-94 V rating and LOI value and lower peak heat release rate (pHRR) value. V0 rating and the highest LOI value are observed with the addition 1 wt% colemanite. The samples get V1 rating for the loading amount of 3 and 5 wt% colemanite. When the concentration of colemanite reaches to 5 wt%, pHRR and average heat release rate (avHRR) values are lower than those of the reference sample. Addition of boron oxide causes improvement in LOI value. The highest LOI value (33.2) is observed in 5 and 10 wt% boron oxide containing samples. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to test proportional‐integral‐derivative (PID) control of air inflow rate in a whole‐room indirect calorimeter to improve accuracy in measuring oxygen (O2) consumption (V̇O2) and carbon dioxide (CO2) production (V̇CO2). Methods: A precision gas blender infused nitrogen (N2) and CO2 into the calorimeter over 24 hours based on static and dynamic infusion profiles mimicking V̇O2 and V̇CO2 patterns during resting and non‐resting conditions. Constant (60 L/min) versus time‐variant flow set by a PID controller based on the CO2 concentration was compared based on errors between measured versus expected values for V̇O2,V̇CO2, respiratory exchange ratio, and metabolic rate. Results: Compared with constant inflow, the PID controller allowed both a faster rise time and long‐term maintenance of a stable CO2 concentration inside the calorimeter, resulting in more accurate V̇CO2 estimates (mean hourly error, PID: −0.9%, 60 L/min = −2.3%, p < 0.05) during static infusions. During dynamic infusions mimicking exercise sessions, the PID controller achieved smaller errors for V̇CO2 (mean: −0.6% vs. −2.7%, p = 0.02) and respiratory exchange ratio (mean: 0.5% vs. −3.1%, p = 0.02) compared with constant inflow conditions, with similar V̇O2 (p = 0.97) and metabolic rate (p = 0.76) errors. Conclusions: PID control in a whole‐room indirect calorimeter system leads to more accurate measurements of substrate oxidation during dynamic metabolic studies. [ABSTRACT FROM AUTHOR]

Crilin (Crystal Calorimeter with Longitudinal Information) is a semi-homogeneous, longitudinally segmented electromagnetic calorimeter based on high-Z, ultra-fast crystals with UV-extended SiPM readout. The Crilin design has been proposed as a candidate solution for both a future Muon Collider barrel ECAL and for the Small Angle Calorimeter of the HIKE experiment. As a part of the Crilin development program, we have carried out beam tests of small (10 × 10 × 40 mm3) lead fluoride (PbF2) and ultra-fast lead tungstate (PbWO4, PWO-UF) crystals with 120 GeV electrons at the CERN SPS to study the light yield, timing response, and systematics of light collection with a proposed readout scheme. For a single crystal of PbF2, corresponding to a single Crilin cell, a time resolution of better than 25 ps is obtained for >3 GeV of deposited energy. For a single cell of PWO-UF, a time resolution of better than 45 ps is obtained for the same range of deposited energy. This timing performance fully satisfies the design requirements for the Muon Collider and HIKE experiments. Further optimizations of the readout scheme and crystal surface preparation are expected to bring further improvements.

The HERD experiment is a future experiment for the direct detection of high-energy cosmic rays and is to be installed on the Chinese space station in 2027. The main objectives of HERD are the first direct measurement of the knee of the cosmic ray spectrum, the extension of electron+positron flux measurement up to tens of TeV, gamma ray astronomy, and the search for indirect signals of dark matter. The main component of the HERD detector is an innovative calorimeter composed of about 7500 LYSO scintillating crystals assembled in a spherical shape. Two independent readout systems of the LYSO scintillation light will be installed on each crystal: the wavelength-shifting fibers system developed by IHEP and the double photodiode readout system developed by INFN and CIEMAT. In order to measure protons in the cosmic ray knee region, we must be able to measure energy release of about 250 TeV in a single crystal. In addition, in order to calibrate the system, we need to measure typical releases of minimum ionizing particles that are about 30 MeV. Thus, the readout systems should have a dynamic range of about 107. In this article, we analyze the development and the performance of the double photodiode readout system. In particular, we show the performance of a prototype readout by the double photodiode system for electromagnetic showers as measured during a beam test carried out at the CERN SPS in October 2021 with high-energy electron beams.

Calorimetric experiments in space of the current and of the next generation measure cosmic rays directly above TeV on satellites in low Earth orbit. A common issue of these detectors is the determination of the absolute energy scale for hadronic showers above TeV. In this work, we propose the use of the Moon–Earth spectrometer technique for the calibration of calorimeters in space. In brief, the presence of the Moon creates a detectable lack of particles in the detected cosmic ray arrival directions. The position of this depletion has an offset with respect to the Moon center due to the deflection effect of the geomagnetic field on the cosmic rays that depends on the energy and the charge of the particle. The developed simulation will explore if, with enough statistics, angular, and energy resolutions, this effect can be exploited for the energy scale calibration of calorimeters on satellites in orbit in Earth’s proximity.

In many superconducting transition-edge sensor (TES) microcalorimeters, the measured electrical noise exceeds theoretical estimates based on a thermal model of a single body thermally connected to a heat bath. Here, we report on noise and complex impedance measurements of a range of designs of TESs made with a Mo/Au bilayer. We have fitted the measured data using a two-body model, where the x-ray absorber and the TES are connected by an internal thermal conductance Gae. We find that the so-called excess noise measured in these devices is consistent with the noise generated from the internal thermal fluctuations between the x-ray absorber and the TES. Our fitted parameters are consistent with the origin of Gae being from the finite thermal conductance of the TES itself. These results suggest that even in these relatively low resistance Mo/Au TESs, the internal thermal conductance of the TES may add significant additional noise and could account for all the measured excess noise. Furthermore, we find that around regions of the superconducting transition with rapidly changing derivative of resistance with respect to temperature, an additional noise mechanism may dominate. These observations may lead to a greater understanding of TES devices and allow the design of TES microcalorimeters with improved performance. [ABSTRACT FROM AUTHOR]

The codes IBC and IFC use acceptance criteria for special products like water resistive barriers, children's playground structures, and plastic rubbish containers. The international standard ISO 5660 Cone Calorimeter test is widely used in fire research and for modeling, but not so often in legislation or requirements on products. ISO International Organization for Standardization, Geneva. [Extracted from the article]

We have launched a new research project named "ONOKORO" to elucidate the formation mechanism of clusters in atomic nuclei. The project comprehensively investigates clustering phenomena in the medium-to-heavy mass region with inverse-kinematics cluster-knockout reactions at the intermediate energy facilities. The new detector array named "TOGAXSI" is under construction for this purpose. It measures scattering angles and the energies of deuterons, tritons, 3 He, and α particles emitted at forward angles from the cluster-knockout reactions. It also measures the recoil protons emitted from the scattering events at large angles. High-angular and high-energy resolutions with wide solid angles are required to achieve a good cluster separation energy resolution and a reasonably high yield. The designed telescope consists of silicon trackers and GAGG:Ce calorimeters. This paper shows the required conditions and design concepts of TOGAXSI. [ABSTRACT FROM AUTHOR]

The procedure for the energy calibration of the high granularity electromagnetic calorimeter PHOS of the ALICE experiment is presented. The methods used to perform the relative gain calibration, to evaluate the geometrical alignment and the corresponding correction of the absolute energy scale, to obtain the nonlinearity correction coefficients and finally, to calculate the time-dependent calibration corrections, are discussed and illustrated by the PHOS performance in proton-proton (pp) collisions at s=13 TeV. After applying all corrections, the achieved mass resolutions for π0 and η mesons for pT > 1.7 GeV/c are σmπ0 = 4.56 ± 0.03 MeV/c2 and σmη = 15.3 ± 1.0 MeV/c2, respectively.

Traceability for power measurements at high millimeter-wave and terahertz frequencies presents significant challenges since traditional waveguide micro-calorimetry systems are only readily available at frequencies up to 110 GHz. There are, however, different types of commercially available power meters which operate at frequencies above 110 GHz, where a lack of traceability means the accuracy and associated uncertainty of measurements using these power meters is not well understood. This paper describes the characterisation and traceable calibration of a commercially available waveguide power meter (VDI Erickson PM5) which is designed to operate from 75 GHz to 3 THz, using appropriate waveguide tapers. This includes an assessment of the overall system performance along with an evaluation of the uncertainty in measurements made using the system. The assessment is carried out at W-band (75 to 110 GHz) by comparison with micro-calorimeter systems which are used as primary standard power measurement systems at these frequencies. [ABSTRACT FROM AUTHOR]

Objective. While the accuracy of dose calculations in water with Acuros XB is well established, experimental validation of dose in bone is limited. Acuros XB reports both dose-to-medium and dose-to-water, and these values differ in bone, but there are no reports of measurements of validation in bone. This work compares Acuros XB calculations to measurements of absolute dose in aluminum (medium similar to bone). The validity of using selected relative dosimeters in aluminum is also investigated. Approach. A calorimeter with an aluminum core embedded in an aluminum phantom was selected as bone surrogate for the measurement of absolute dose. Matching the medium of the core to the medium of the phantom allowed eliminating the calculation of the conversion between media. The dose was measured at the fixed depth of 3.3 cm in aluminum (∼9 g·cm−2) with 6X, 10X, 6FFF and 10FFF photon beams from a TrueBeam Varian linac. In addition, experimental cross-calibration between water and aluminum was performed for an IBA CC13 ionization chamber, a PTW microDiamond and EBT3 Gafchromic film. Main results. Calculations with Acuros XB dose-to-medium in aluminum differed from the calorimetry data by −2.8% to −3.5%, depending on the beam. Use of dose-to-water would have resulted in about 39% discrepancy. The cross calibration coefficient between water and aluminum yielded values of about 0.87 for the CC13 chamber, 0.91 for the microDiamond, and 0.88 for the film, and independent of the beam within about ±1%. Significance. It was demonstrated the value of the dose-to-medium in aluminum (surrogate of bone) computed with Acuros XB is close to the value of the absolute dose measured with a calorimeter, and there is a significant discrepancy when dose-to-water is used instead. The use of an ionization chamber, a microDiamond and Gafchromic film in aluminum required a considerable correction from calibration in water. [ABSTRACT FROM AUTHOR]