Resistive Anode Research Articles

A triangular-trapezoidal dual-channel shaping algorithm for resistive anode readout systems and its FPGA implementation.

This paper introduces a novel digital triangular-trapezoidal double-channel shaping algorithm to enhance the counting rate of resistive anode detectors. The algorithm is based on the trapezoidal shaping algorithm and improves it. At the extreme counting rate, the trapezoidal shaping algorithm cannot alleviate the pulse pileup, so the counting rate cannot meet the requirements of a high performance detector. The triangular-trapezoidal double-channel shaping algorithm is introduced in the resistance anode detector, which can replace the trapezoidal shaping filtering algorithm to process the output signal of the resistance anode detector and obtain the single photon position information. This improvement improves the counting rate of the resistor anode detector and reduces the resolution degradation caused by pulse pileup. The algorithm is simulated by System Generator software and implemented on FPGA (field programmable gate array). The triangular-trapezoidal double-channel shaping algorithm presented in this paper plays an important role in reducing electronic noise and pulse pileup. The algorithm is subjected to simulation testing, and it can recognize signals with a minimum pulse interval of 1 µs and counting rate up to 1000 kcps.

Exsolved NiRu bimetallic nanoparticles induced by Ru doping in LaBaMn1.6Ni0.3Ru0.1O5+δ as a coking resistant anode catalyst layer for direct-methane solid oxide fuel cells

Due to its abundant resources and advantages in transportation and storage, methane fueled solid oxide fuel cells (SOFCs) are highly needed. In this work, an exceptional internal reforming catalyst comprising in-situ exsolved NiRu bimetallic nanoparticles and oxygen-deficient layered double perovskite LaBaMn1.6Ni0.3Ru0.1O5+δ (r-LBMNR) was prepared. Compared to the cell with LaBaMn1.6Ni0.4O5+δ (r-LBMN) catalyst, the cell with a Ru-doping r-LBMNR catalyst layer, exhibits superior peak power output of 336 mW cm−2 and better durability with a less decay rate of 0.014% per hour in CH4 fuel. The enhanced electrochemical performance can be attributed to the high oxygen ion and electron conductivities of the catalyst and the coupling of Ni and Ru sites with the oxygen-deficient r-LBMNR matrix This coupling activates CH4 and H2O, promotes the oxidation of C atoms in CH4 molecules, and enables reversible hydrogen spillover, ultimately leading to the production syngas of CO(g) and H2(g).

Design of electronic readout system for resistive anode based on FPGA

Design of electronic readout system for resistive anode based on FPGA

Characterisation of resistive MPGDs with 2D readout

Micro-Pattern Gaseous Detectors (MPGDs) with resistive anode planes provide intrinsic discharge robustness while maintaining good spatial and time resolutions. Typically read out with 1D strips or pad structures, here the characterisation results of resistive anode plane MPGDs with 2D strip readout are presented. A µRWELL prototype is investigated in view of its use as a reference tracking detector in a future gaseous beam telescope. A MicroMegas prototype with a fine-pitch mesh (730 line-pairs-per-inch) is investigated, both for comparison and to profit from the better field uniformity and thus the ability to operate the detector more stable at high gains. Furthermore, the measurements are another application of the RD51 VMM3a/SRS electronics.

Parallel-plate avalanche counters for heavy-ion beam tracking: History and mysteries

Despite being an old detector concept, position-sensitive parallel-plate avalanche counters (PPACs) remain widely used today for heavy-ion position and timing measurements. In modern rare isotope beam facilities and large-acceptance fragment separators, PPACs are used to characterize beam properties (diagnostics), facilitate beam delivery (tuning), and provide event-by-event beam tracking for particle identification (PID). Most popular particle localization methods in PPAC detectors are based on strip electrodes electrically connected to resistive-chain circuits or delay lines. More exotic systems include optical readouts based on recording electroluminescence light with high-granularity photodetector arrays or high-resolution resistive anode electrodes. PPACs with conventional resistive-chain or delay-line readouts achieve typical position and time resolutions of below 1 mm (σ) and around 150 ps (σ), respectively. In addition, delay-line systems are capable of counting rates above several hundred kHz for beam areas of a few millimeters square, and around 1 MHz for larger beam sizes. Resistive-chain readouts have limited rates of a few tens of kHz. A review of the operation principles and performance of PPAC detectors is presented in this paper. We will discuss decades-long experience building and operating PPACs developed at the National Superconducting Cyclotron Laboratory, and then refined at the Facility for Rare Isotope Beams (FRIB), mostly focusing on the delay-line readout technique (DLPPAC). We will also discuss problems that arise due to electric discharges at high rates and briefly describe ongoing developments at FRIB. Published by the American Physical Society 2024

Fracture Resistant CrSi2-Doped Silicon Nanoparticle Anodes for Fast-Charge Lithium-Ion Batteries.

Lithium-ion batteries (LIBs) has been developed over the last three decades. Increased amount of silicon (Si) is added into graphite anode to increase the energy density of LIBs. However, the amount of Si is limited, due to its structural instability and poor electronic conductivity so a novel approach is needed to overcome these issues. In this work, the synthesized chromium silicide (CrSi2) doped Si nanoparticle anode material achieves an initial capacity of 1729.3mAhg-1 at 0.2C and retains 1085mAhg-1 after 500cycles. The new anode also shows fast charge capability due to the enhanced electronic conductivity provided by CrSi2 dopant, delivering a capacity of 815.9mAhg-1 at 1C after 1000cycles with a capacity degradation rate of <0.05% per cycle. An in situ transmission electron microscopy is used to study the structural stability of the CrSi2-doped Si, indicating that the high control of CrSi2 dopant prevents the fracture of Si during lithiation and results in long cycle life. Molecular dynamics simulation shows that CrSi2 doping optimizes the crack propagation path and dissipates the fracture energy. In this work a comprehensive information is provided to study the function of metal ion doping in electrode materials.

Characterization of charge spreading and gain of encapsulated resistive Micromegas detectors for the upgrade of the T2K Near Detector Time Projection Chambers

An upgrade of the near detector of the T2K long baseline neutrino oscillation experiment is currently being conducted. This upgrade will include two new Time Projection Chambers, each equipped with 16 charge readout resistive Micromegas modules.A procedure to validate the performance of the detectors at different stages of production has been developed and implemented to ensure a proper and reliable operation of the detectors once installed. A dedicated X-ray test bench is used to characterize the detectors by scanning each pad individually and to precisely measure the uniformity of the gain and the deposited energy resolution over the pad plane. An energy resolution of about 10% is obtained.A detailed physical model has been developed to describe the charge dispersion phenomena in the resistive Micromegas anode. The detailed physical description includes initial ionization, electron drift, diffusion effects and the readout electronics effects. The model provides an excellent characterization of the charge spreading of the experimental measurements and allowed the simultaneous extraction of gain and charge spreading information of the modules.

Effect of multiple discharges on accumulated damage to the DLC anode layer of a resistive Well Electron Multiplier

A prototype of the WEM (Well Electron Multiplier) detector with an active area of 10 × 10 mm2 and a resistive DLC anode was tested in terms of robustness to electrical discharges induced by highly ionizing particles (241Am alpha source). The perforated structure of the WEM detector was produced from a 500 μm thick FR4 with drilled holes of 200 μm in diameter and 500 μm in pitch. The resistive anode was made of 100 nm thick DLC layer with 30 MOhm/square sheet resistance deposited on the anode grid electrode. The anode grid electrode is used to distribute voltage to the resistive layer and provide fast charge evacuation. The detector was operated in Ar:CO2 (90:10) gas mixture at gas gain of 3,500. The alpha source was placed in the drift gap. The WEM detector with intrinsic capacitance of 34 pF did not show visible damage and changes in performance after 1 million accumulated discharges. To simulate a large area detector, we added a capacitance up to 1 nF in parallel with the test device. The results of the experiments with an additional capacitance revealed that a small WEM prototype can't be directly scaled to the dimensions more than 60 × 60 mm2 without losing the robustness to discharges. We assume that the observed damage could be caused by the design features of the prototype. The grid anode electrode with a thickness of 35 μm results in a gap between the perforated FR4 board and the resistive anode board. Simulations of the electric field distribution with Comsol Multiphysics software revealed a significant electric field strength in this gap. This could lead to electric discharge path bypassing the protective resistive DLC layer. A possible solution to this problem could be additional insulation of the anode grid electrode with a coverlay similar to that used in bulk MicroMegas production.

Starch‐Based Superabsorbent Hydrogel with High Electrolyte Retention Capability and Synergistic Interface Engineering for Long‐Lifespan Flexible Zinc−Air Batteries

AbstractThe advent of wearable electronics has strongly stimulated advanced research into the exploration of flexible zinc−air batteries (ZABs) with high theoretical energy density, high inherent safety, and low cost. However, the half‐open battery structure and the high concentration of alkaline aqueous environment pose great challenges on the electrolyte retention capability and the zinc anode stability. Herein, a starch‐based superabsorbent hydrogel polymer electrolyte (SSHPE) with high ionic conductivity, electrolyte absorption and retention capabilities, strong alkaline resistance and high zinc anode stability has been designed and applied in ZABs. Experimental and calculational analyses probe into the root of the superiority of SSHPEs, confirming the significance of the carboxyl functional groups along their polymer chains. These features endow the as‐fabricated ZAB a long cycle life of 300 h, much longer than that with commonly used poly(vinyl alcohol)‐based electrolyte.

Starch-Based Superabsorbent Hydrogel with High Electrolyte Retention Capability and Synergistic Interface Engineering for Long-Lifespan Flexible Zinc-Air Batteries.

The advent of wearable electronics has strongly stimulated advanced research into the exploration of flexible zinc-air batteries (ZABs) with high theoretical energy density, high inherent safety, and low cost. However, the half-open battery structure and the high concentration of alkaline aqueous environment pose great challenges on the electrolyte retention capability and the zinc anode stability. Herein, a starch-based superabsorbent hydrogel polymer electrolyte (SSHPE) with high ionic conductivity, electrolyte absorption and retention capabilities, strong alkaline resistance and high zinc anode stability has been designed and applied in ZABs. Experimental and calculational analyses probe into the root of the superiority of SSHPEs, confirming the significance of the carboxyl functional groups along their polymer chains. These features endow the as-fabricated ZAB a long cycle life of 300 h, much longer than that with commonly used poly(vinyl alcohol)-based electrolyte.

Analysis of test beam data taken with a prototype of TPC with resistive Micromegas for the T2K Near Detector upgrade

In this paper we describe the performance of a prototype of the High Angle Time Projection Chambers (HA-TPCs) that are being produced for the Near Detector (ND280) upgrade of the T2K experiment. The two HA-TPCs of ND280 will be instrumented with eight Encapsulated Resistive Anode Micromegas (ERAM) on each endplate, for a total of 32 ERAMs. This innovative technique allows the detection of the charge emitted by ionization electrons over several pads, improving the determination of the track position.The TPC prototype has been equipped with the first ERAM module produced for T2K and with the HA-TPC readout electronics chain and it has been exposed to an electron beam at DESY in order to measure spatial and dE/dx resolution. In this paper we characterize the performances of the ERAM and, for the first time, we compare them with a newly developed simulation of the detector response.Spatial resolution better than 800 μm and dE/dx resolution better than 10% are observed for all the incident angles and for all the drift distances of interest. All the main features of the data are correctly reproduced by the simulation and these performances fully fulfill the requirements for the HA-TPCs of T2K.

Carbon resistant Ni1-xCux-BCZY anode for methane-fed protonic ceramic fuel cell

This research aims to develop a better carbon resistant anode compared to conventional Ni-BCZY anode for methane fueled protonic ceramic fuel cell (PCFC). Solid-state reaction process is used to prepare alloy Ni1-xCux-BCZY anode in PCFC. Ni is doped with Cu for better carbon resistance. Results show that, Ni0·9Cu0.1-BCZY anode calcined at 800 °C for 0.5 h exhibit an electrical conductivity of 2054 S/cm at 600 °C, which is 8.4% less than traditional Ni-BCZY anode. XPS, and Raman data show that Ni0·9Cu0.1-BCZY anode exhibit resistance to carbon deposition compared to traditional anode. The best carbon deposition resistance is observed for the Ni0·7Cu0.3-BCZY sample. This work demonstrates the suppression of carbon deposition and inhibition of anode deformation in methane fueled PCFC with Ni1-xCux-BCZY anode. This work is helpful for development of carbon-resistant materials for energy generation with solid oxide fuel cells.

Reproducible polarization test methods and fair evaluation of polarization data by using interconversion factors in a single chamber cubic microbial fuel cell with a brush anode

MFC research has been conducted enormously in the last decade, and their electrochemical data has been accumulated enormously. Although reproducible measurement method and fair evaluation are essential elements in research, these elements are missing in MFC research. Herein, using single-chamber cubic MFCs, diverse polarization methods were conducted along with other electrochemical tests. 3-hour optimum resistance operation followed by 2-h open circuit time prevented power overshoots. In a faster polarization method, data reproducibility increased drastically, power and current were larger, and polarization resistance was smaller. In ERC-30 min, LSV-0.1, LSV-1, LSV-10 mV/s and, maximum power density was 1242, 1518, 2287 and 3417 mW/m2, and internal resistance 76, 63, 48 and 35 Ω, respectively. For fair evaluation of different polarization data, the interconversion factors were developed and applied. During the optimum resistance operation, average power and current densities were 994 mW/m2 and 3767 mA/m2, respectively. As similarly in the polarization tests, cathodic impedances (24.1 Ω) were 2.4 times larger than the anodic impedances (10.2 Ω). Charge transfer impedance (32.4 Ω) was the major component (>95%) in the electrodes and the whole cell (34.3 Ω). Ohmic impedance was detected only in the anode (0.2 Ω), and diffusion impedance was detected only in the cathodes (1.7 Ω). Cathodic capacitance (1.62 F) was 2.5 times larger than the anodic capacitance (0.64 F). Cyclic voltammogram cathodic capacitance (7.78 F) was 1.6 times larger than the anodic capacitance (4.76 F). Longer operation, lower internal resistance and higher anode performance increased coulombic and energy efficiencies. This study contains very important information on experimental accuracy and reproducibility, essential elements in research, and will greatly contribute to the firm foundation and the meaningful growth of the MFC research.

Position linearity analysis of circular arc terminated resistive anode using finite element method for photon-counting imaging detectors.

This study proposes a comprehensive model of the circular arc terminated (CAT) resistive anode based on the finite element method to explore the dynamic process of charge diffusion on this anode and its position linearity performance. The waveforms of charges of the electrodes on the anode are calculated for different electrical parameters and their influence on positional linearity is investigated. The influence of the signal development time and the non-uniformity of the resistance per square of the anode on positional linearity is also analyzed. The results of simulations show that the non-linearity of the image varies monotonically with the termination resistance and the non-uniformity of the resistance per square of the anode, but has a non-linear relationship with the signal development time and the ratio of the resistance per square. A CAT resistive anode with capacitance c and a resistance per square of the sensitive area of R▱ can be used to recover an image with a root mean-squared non-linearity of 2%, when the charge signals of the electrode are collected for at least 0.6R▱c s. The reliability of the results of the simulations was verified with experimental measurements.

High granularity small-pad resistive micromegas for rates above MHz/cm[formula omitted

An R&D project has been recently started to consolidate the technology of resistive Micromegas for operations well beyond the actual operations at HEP experiments, aiming at stable, reliable, and high gain operation up to particle fluxes of the order of 10 MHz/cm2, over large surfaces.To cope with these challenges, readout copper pads, of a few mm2 size, have been proposed to reduce the occupancy of the readout elements, calling for innovative solutions for the spark protection resistive scheme. It is known that single stage amplification Micro Pattern Gaseous Detectors suffer from sparks when operated under harsh environments. Resistive anodes drastically mitigate the spark intensities but, on the other hand, they reduce the rate capability when high currents flow into the detectors, generating a drop in the amplification voltage. Ad-hoc solutions must be adopted.Two resistive schemes have been studied. The first one is based on a pad-patterned resistive double layer, superimposed to the readout pads, with an embedded resistor connecting the resistive pads. In this scheme, each pad is independent from the others. The second scheme exploits the recently developed Diamond-Like Carbon (DLC) resistive foils. A double layer of DLC is superimposed to the readout pads, with a grid of interconnecting vias to ground for a fast evacuation of the accumulated charge. In this case the pads are not completely independent since the charge can spread over more pads. For each of these resistive schemes, detectors with different configurations and construction techniques have been built.All detectors have been thoroughly tested and fully characterized with radioactive sources, X-rays and with test beams carried out at CERN in 2021. The performance and achievements in terms of gains, rate capabilities, energy, space and time resolutions will be reported, along with a detailed comparison among the different schemes and configurations.

Encapsulated resistive anode bulk Micromegas detectors for the T2K experiment TPC upgrade

In order to establish accurate leptonic CP violation at 3 σ level for a significant fraction of the possible δCP values, the T2K collaboration plan to upgrade the beam intensity and to upgrade the near detector ND280.The T2K experiment consists of a totally active Super-Fine-Grained-Detector, two High Angle Time Projection Chamber and six time of flight planes. The HA-TPC will be used for 3D track reconstruction, momentum measurement and particle identification. These time projection chambers, with overall dimensions of 2 × 2 × 0.8 m3, will be equipped with 32 encapsulated resistive anode bulk Micromegas detectors. The thin field cage (3 cm thickness, 4% radiation length) will consist of composite material with a Kapton foil with copper strips as inner layer. The 42 × 34 cm2 ERAM detector will use a 400 kΩ/sq diamond-like carbon foil to spread the charge over the pad plane, each pad being approximately 1 cm2. New front-end electronic cards, based on the AFTER chip, directly mounted on the back of the detector and parallel to its plane have been developed and used for the signal readout.The first production ERAM detector modules have been tested in a lab using a X-ray bench and a cosmic bench. In July 2021, data have also been taken in a test beam at DESY in 0.2 T magnetic field. Performance characterization and results from these measurement campaigns will be shown.

Development of a Segmented GEM Readout detector

Micromegas (Micro-MEsh GAseous Structures) detectors are a type of micro-pattern gaseous detectors. The primary charges are amplified in electron avalanches between a planar anode and a mesh typically 120 μm above the anode. For resistive anode type Micromegas detectors the signal is read out via copper readout strip layers below the anode. A 2D particle position can be reconstructed using two perpendicular readout strip layers below the resistive anode structure.Using a standard 2D resistive anode Micromegas readout structure, a unique 2D particle position reconstruction is only possible if the detector is hit by only one particle at the same time. Ambiguities will occur if multiple particles arrive at the same time. A unique X–Y assignment is strongly complicated.This issue can be resolved by replacing the mesh with a GEM (Gas Electron Multiplier) foil, which is segmented into 0.5 mm wide strips on at least one of the two sides. The GEM strips need to be turned by 45∘ with respect to the Micromegas readout strips. Thus the detector with a GEM foil segmented on both sides has four readout strip directions (X, Y, U and V) and a detector with a GEM foil segmented on only one side has three readout strip directions (X, Y and V).A prototype of such a Segmented GEM Readout (SGR) detector is built with GEM strips and readout strips perpendicular to each other. Test beam measurements with this detector were performed using 120 GeV muons. Results of the test beam measurements are presented here.

Electrical discharges and their effect in a Resistive Plate WELL detector

Resistive Plate WELL is a Thick-GEM based WELL detector that utilizes a resistive anode to quench substantially the energy released in discharges. We present a method developed to identify these low-energy discharges and use it to study their effect on the detector gas gain as a function of distance from the discharge location and time.

Design and Performance of Photon Imaging Detector Based on Cross-Strip Anode with Charge Induction

Imaging detectors based on a microchannel plate (MCP) and charge division anode with charge induction have broad applications in particles (photons, neutrons, ions, and electrons) detection. However, the application of a charge induction readout mode is mostly focused on planar anodes, and there are few reports on double-layer cross-strip (XS) anodes with high spatial resolution and low gain requirements. In this paper, we design the parameters of the resistive layer and XS anode by theoretical derivation and the three-dimensional finite element method, including the sheet resistance, substrate thickness, strip width, and insulation thickness. The performance of the XS detector is characterized with the help of a resolution target and full field illumination using three different centroid algorithms. We conclude that the modified center of gravity (MCoG) has best imaging performance, which achieves a spatial resolution of 44.2 μm with a periodic distortion about 25.8%.

NiO-Ba0.95Ca0.05Ce0.9Y0.1O3-δ as a Modified Anode Material Fabricated by the Tape Casting Method.

The development of new chemically resistant anodes for protonic ceramic fuel cells (PCFCs) is urgently required to avoid the costly deep hydrogen purification method. Ba0.95Ca0.05Ce0.9Y0.1O3−δ (5CBCY), which is more chemically resistant than BaCaCe0.9Y0.1O3−δ, was here tested as a component of a composite NiO–5CBCY anode material. A preparation slurry comprising 5CBCY, NiO, graphite, and an organic medium was tape cast, sintered and subjected to thermal treatment in 10 vol.% H2 in Ar at 700 °C. Differential thermal analysis, thermogravimetry, quadrupole mass spectrometry, X-ray diffraction analysis, scanning electron microscopy, the AC four-probe method and electrochemical impedance spectroscopy were used for the investigation. The electrical conductivity of the Ni–5CBCY in H2–Ar at 700 °C was 1.1 S/cm. In the same gas atmosphere but with an additional 5 vol.% CO2, it was slightly lower, at 0.8 S/cm. The Ni–5CBCY cermet exhibited repeatable electrical conductivity values during Ni-to-NiO oxidation cycles and NiO-to-Ni reduction in the 5CBCY matrix, making it sufficient for preliminary testing in PCFCs.