Typhoons, also known as tropical cyclones, rely heavily on the dynamic evolution of internal refined structures (e.g., eyewall pressure gradients and core density distributions) for accurate intensity forecasting. However, inherent limitations in the penetration depth and spatial resolution of conventional atmospheric density imaging techniques preclude the direct observation of internal refined structures of typhoons. Therefore, this paper proposed a large-area muography for atmospheric density imaging techniques based on low-cost, high-performance thin gap chamber (TGC). Considering the correlation between the flux of cosmic-ray muons and atmospheric density, this study developed a system to achieve atmospheric muography, providing critical data support for the retrieval of real time pressure field distribution in the typhoon core region. The system employs a 384-channel TGC detector array, comprising two identical double-layer TGC units. Each unit includes an orthogonal readout structure composed of 96 anode wires and 96 cathode strips. The data acquisition system adopts a distributed architecture, where two FEBs and one DAQ board are combined to implement muon event selection for multilayer detectors. The final three-dimensional muon track reconstruction was completed offline. This prototype system has been deployed on the “Tongji · Marine No.1” Observation Tower in the East China Sea, enabling continuous real-time data acquisition. The preliminary test results of the muon angle distribution and the variation of the system counting rate are presented in this paper. The developed atmospheric muography system represents a novel technological approach for probing the internal structure of typhoons, offering the potential to overcome the limitations of traditional methods and to support improved intensity forecasting.

A novel compact charge readout method based on Field Programmable Gate Array (FPGA) was proposed. In the highly integrated charge readout method, it consists of a dual-polarity Charge-to-Time Converter (dQTC) and digital FPGA. We refer to this new FPGA-based charge measurement method as FPGA-dQTC. In the FPGA-dQTC method, an FPGA LVDS receiver serves as a voltage comparator. To achieve a compact charge readout, the FPGA I/O port was configured as voltage-referenced receiver instead of LVDS receiver. The single-ended voltage-referenced receivers share common reference voltage in each I/O Bank of the FPGA, which maximizes the capability of multi-channel and multi-functionality in our proposed charge measurement method. Experiments in terms of channel linearity and timing performance for the FPGA-dQTC method were carried out. A Coincidence Timing Resolution (CTR) evaluation setup including two PET detectors was built. Each PET detector comprises a 3x3x10 mm3 LYSO crystal coupled with a SiPM detector. The energy resolutions were 10.23% and 10.56% for the two PET detectors. The CTR values between the two detectors were 291 ps for cathode signal of the SiPM. Experiment results show that the FPGA-dQTC scheme provides a promising method for a compact, multi-channel front end readout electronics for nuclear detection applications.

Time-of-flight (TOF) capability of positron emission tomography (PET) can improve the signal-to-noise ratio (SNR) in the image reconstruction. A new high-density and compact front-end electronics design for TOF-enabled and position sensitive PET detectors was proposed and evaluated. The proposed readout scheme employs radio frequency (RF) amplifiers for timing readout and an FPGA-based dual-polarity charge-to-digital converter (FPGA-dQDC) for energy readout. The PET detector consists of a 15 × 15 array of 1 × 1 × 10 mm^3 LYSO crystals coupled to a 5 × 5 array of 3 × 3 mm^2 SiPMs through a light guide. All crystals are separated by enhanced specular reflector (ESR) films. The timing signals from the SiPM array are amplified and multiplexed with a 25:1 ratio, while the energy signals are multiplexed by row/column summation to form a " 5+5 " readout configuration. The FPGA-dQDC system consists of an analog board implementing the dQDC circuit and a digital board based on a Cyclone V FPGA for discharge control, data buffering, and digital processing. The system was evaluated using a dual-detector coincidence setup consisting of a single-crystal reference detector and the " 5+5 " PET detector. The average coincidence time resolution (CTR) obtained from the CTR map was measured to be 381.68 ± 9.80 ps full width at half maximum (FWHM). After saturation correction, the average energy resolution of all crystals was 10.83 ± 0.68% . The proposed RF-amplifier-based timing readout and FPGA-dQDC energy readout scheme enables compact and power-efficient front-end electronics for TOF-PET detector prototype development.

Traditional digitizers for signal readout of PET detectors are based on commercial analog-to-digital converters (ADC). However, the cost and power consumption of an entire electronic readout system based on digitizers for a PET scanner are high. To address this problem, a soft-core ADC based on a field-programmable gate array (FPGA) was proposed. An FPGA-based ADC (FPGA-ADC) combines low loss and high performance. To achieve good performance, the FPGA-ADC requires three calibrations: time-to-digital converter (TDC) length calibration, TDC alignment calibration, and TDC-to-ADC calibration. A prototype front-end electronics based on FPGA-ADC was built to evaluate the performance of time-of-flight positron emission tomography (TOF PET) detectors. Each PET detector consists of a LYSO crystal single-ended coupled to a silicon photomultiplier (SiPM). The experimental results show that the full-width at half-maximum (FWHM) energy resolution for 511 keV gamma photons after saturation correction of the SiPM was 12.3%. The FWHM coincidence timing resolution (CTR) of the TOF PET detector with the readout of the front-end electronic prototype is 385.2 ps. FPGA-ADC-based front-end electronics are very promising for multichannel, low-cost, highly integrated, and power-efficient readout electronic systems for radiation detector applications.

Timing performance plays a vital role in radiation detector applications. Recently, two kinds of charge readout methods based on field programmable gate array (FPGA), namely FPGA-based charge-to-digital converter (FPGA-QDC) and FPGA-based charge-to-time converter (FPGA-QTC), were proposed. In comparison with traditional time over threshold (ToT), they can not only achieve high-precision timing pickoff but also accurately measure charge from radiation detectors. Both of them are the mixed-signal circuits. In both circuits, analog part consists of an operational amplifier, few resistors and capacitors. In digital part, all function modules are implemented in the FPGA. Specifically, an FPGA LVDS receiver works as a general voltage comparator. A time-to-digital converter (TDC) was developed to calculate the pulse width of the digital signal. To compare the timing performance of both circuits, a coincidence timing resolution (CTR) evaluation setup comprising two TOF PET detectors was constructed. Each PET detector was made up of one 3 & times; 3 & times; 10 mm3 LYSO crystal bar coupled with a SiPM detector at one end. Results show the best CTR values between the two PET detectors were 335.03 +/- 2.00 ps and 357.86 +/- 3.31 ps full width at half maximum (FWHM) for the FPGA-QDC and FPGA-QTC respectively. Both are promising circuits for a power-efficient, multi-channel and low-cost front end readout electronics for nuclear radiation detectors.

Muon tomography is a non-destructive imaging technique that uses cosmic-ray muons to probe dense materials. A plastic scintillating fiber (SciFi) detector with a one-dimensional SiPM array offers a compact, high-resolution solution. However, scaling up the detector area and spatial resolution demands reducing the number of readout channels while maintaining detector performance. To address this challenge, this work presents a multiplexing scheme based on a diode-based symmetric charge division circuit combined with a position-encoding algorithm. Circuit simulations confirm the feasibility of the multiplexing design and guide the selection of suitable diodes to preserve SiPM signal integrity. Electronic tests show that the proposed design exhibits low crosstalk among electronic channels, and preserves linearity over a dynamic range spanning a few to several hundred photoelectrons. Cosmic-ray measurements further demonstrate that the multiplexed SciFi detector achieves a detection efficiency above 95% and a spatial resolution of about 0.65 mm, with only minor degradation compared to direct readout. These results verify that the proposed method offers a scalable and cost-effective readout solution for large-area muon tomography systems.

Positron emission tomography (PET) is an indispensable medical image technology today. An advanced data acquisition (DAQ) system based on a dual-polarity charge-to-digital converter (dQDC) for PET detector application was proposed. The DAQ consists of two parts: an analog board and a digital board. The analog board assembles all analog components in the dQDC scheme, while the core of the digital board is a low-cost field programmable gate array (FPGA). In the dQDC implementations, the single-ended voltage-referenced receivers in the FPGA serve as voltage comparators. Under this configuration, two input/output (I/O) pins of the FPGA can be used to perform one-channel charge measurement. Taking advantage of abundant I/O resources in the FPGA, a multi-channel DAQ based on the dQDC scheme can be quickly customized. A total of 128 channels of dQDCs are integrated into the DAQ on the 80 x 80 mm(2) area. To confirm the readout capability of the DAQ, a PET detector was constructed, which consisted of a 15 x 15 array of 1.5 x 1.5 x 20 mm(3) lutetium yttrium oxyorthosilicate (LYSO) bars coupled with a silicon photomultiplier (SiPM) detector at one end. The energy resolution of the PET detector ranges from 13.11% to 22.71%. To measure the timing performance of the PET detector, a reference detector was applied. With the DAQ system, experimental results showed that the coincidence timing resolution (CTR) of the two detectors can reach 722.9 ps in full width at half maximum (FWHM). This new dQDC scheme is very promising for the low-cost DAQ with hundreds of channels.

Electromagnetic Calorimeter (ECal), a subdetector of Multipurpose Detector (MPD), is designed to identify electrons, photons, and neutral hadrons produced in high-energy heavy-ion collisions at nuclotron-based ion collider facility (NICA) and measure their energies and positions. A Shashlyk-type sampling calorimeter composed of lead plates as absorbers and plastic scintillators arranged alternately was selected for ECal. Chinese MPD consortium is responsible for the development of 768 ECal modules which is 1/3 of the whole ECal detector. In this report, the mass production process of ECal modules and a performance test system designed for the mass production will be presented. The uniformity of the ECal modules achieved based on cosmic ray test will be discussed. Preliminary results demonstrate the produced ECal modules met the design requirements, indicating the quality control in mass production is effective. These modules were delivered to the Joint Institute for Nuclear Research (JINR) at Dubna in March 2023, and will soon be installed on MPD detector for further commissioning.

The Circular Electron Positron Collider (CEPC) is a large scientific project initiated and hosted by China, fostered through extensive collaboration with international partners. The complex comprises four accelerators: a 30 GeV Linac, a 1.1 GeV Damping Ring, a Booster capable of achieving energies up to 180 GeV, and a Collider operating at varying energy modes (Z, W, H, and ttbar). The Linac and Damping Ring are situated on the surface, while the Booster and Collider are housed in a 100 km circumference underground tunnel, strategically accommodating future expansion with provisions for a Super Proton Proton Collider (SPPC). The CEPC primarily serves as a Higgs factory. In its baseline design with synchrotron radiation (SR) power of 30 MW per beam, it can achieve a luminosity of 5e34 /cm^2/s^1, resulting in an integrated luminosity of 13 /ab for two interaction points over a decade, producing 2.6 million Higgs bosons. Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons, facilitating precise measurements of Higgs coupling at sub-percent levels, exceeding the precision expected from the HL-LHC by an order of magnitude. This Technical Design Report (TDR) follows the Preliminary Conceptual Design Report (Pre-CDR, 2015) and the Conceptual Design Report (CDR, 2018), comprehensively detailing the machine's layout and performance, physical design and analysis, technical systems design, R&D and prototyping efforts, and associated civil engineering aspects. Additionally, it includes a cost estimate and a preliminary construction timeline, establishing a framework for forthcoming engineering design phase and site selection procedures. Construction is anticipated to begin around 2027-2028, pending government approval, with an estimated duration of 8 years. The commencement of experiments could potentially initiate in the mid-2030s.

Integration of solar cells and electrochromic windows offers crucial contributions to green buildings. Solar-charging zinc anode-based electrochromic devices (ZECDs) present opportunities for addressing the solar intermittency issue. However, the limited energy storage capacity of ZECDs results in wasted harnessing of solar energy as well as overcharging. Herein, spectral-selective dual-band ZECDs that continuously transport solar energy to indoor appliances by remotely controlling the repeated bleached-tinted cycles during the daytime, are reported. Hexagonal phase cesium-doped tungsten bronze (h-Cs0.32WO3, CWO) nanocrystals are adopted for dual-band ZECDs due to their independent control ability of near-infrared (NIR) and visible (VIS) light transmittance (∆T = 73.0%, 700 nm; ∆T = 83.7%, 1200 nm) and excellent cycling stability (0.8% optical contrast decay at 1200 nm after 10 000 cycles). The prototype device (i.e., CWO//Zn//CWO) delivers extraordinary thermal insulation capability, displaying a 10 °C difference between "bright" and "dark" modes. Furthermore, an Internet of Things (IoT) controller to control the NIR and VIS lights of the CWO//Zn//CWO window wirelessly with a smartphone, empowering the continuous discharging of the solar-charged window during the daytime remotely, is developed. Such windows represent an intriguing potential technology whose future impact on green buildings may be substantial.

A soft-core analog-to-digital converter (ADC) based on multichain merged time-to-digital converter (TDC) is proposed. In hardware design, it only requires one resistor and a field-programmable gate array (FPGA). The soft-core ADC is implemented in the FPGA. The FPGA-based ADC (FPGA-ADC) needs to be calibrated including TDC length calibration, TDC alignment calibration, and TDC-to-ADC code calibration. We implement the FPGA-ADCs with 1-, 2-, 4-, 6-, and 8-chain merged TDC. The resulting FPGA-ADC can achieve a best resolution of more than 10 bits and a best 6.7 bits effective number of bits (ENOB) over a 0.67-2.03 V input dynamic range at a 200 MS/s sampling rate. The advantages of the proposed soft-core ADC are its compact size, reconfigurability, and high resolution, which provide a feasible approach to achieve different readout electronics system on single hardware platform.

The muon detector (MUD), serving as the outermost detector of the high-precision spectrometer in STCF, is used to provide muon identification in the presence of a significant pion background. The accuracy of muon identification relies heavily on excellent momentum resolution, which can be determined by their flight trajectory positions. Physical simulations of the measurement precision for reconstructed muons indicate that a spatial resolution of 2 cm is required. In the barrel MUD, a double-ended readout is required to determine the hit position, with a time resolution requirement of approximately 500 ps. To meet the readout requirements of the MUD, a comprehensive scheme for the front-end readout electronics of the STCF MUD is proposed, and a prototype of MUD readout electronics is developed. To validate the final 8-channel application-specific integrated circuit (ASIC) design, an 8-channel time-to-digital converter (TDC) is implemented using a field programmable gate array (FPGA). The results of the electronics tests demonstrate that the average root mean square (RMS) precision ranges from 14 to 16 ps for each channel within a 1∼20 ns time interval. In the joint test with the detector, the system achieves a single-channel RMS precision of 297 ps, with a detection efficiency exceeding 95.5%. All indicators meet project requirements. This validates that the prototype is capable of preliminary evaluation and parameter optimization of the STCF MUD.

As silicon photomultiplier (SiPM) technology develops, its possible applications are being growingly expanded. However, the current technical obstacle is the signal readout from large-scale, multi-pixel SiPMs, especially in a large nuclear imaging device. Although the application-specific integrated circuits (ASICs) provide ways to reach that goal, it needs a long period with iterative electronic process and a very high cost. We developed a high-integrated positron emission tomography (PET) electronics system with field programmable gate array based charge-to-digital converter (FPGA-QDC) technology instead of the ASICs. Unlike traditional FPGA-based charge readout method in which low-voltage differential signaling (LVDS) receivers serve as analog voltage comparators, in the proposed electronics system voltage-referenced receivers work as analog comparators.Theoretically, nearly all of input/output (I/O) ports in the FPGA can achieve the function of analog comparators using voltage-referenced I/O standard. The electronics system is constructed using offthe-shelf low-cost commercial components. Therefore, it is feasible to fast build a distributed readout system with multiple such electronics system. The flexibility and reconfigurability of the FPGA provide multi-channel grouping and diverse triggering for different kinds of detector configurations, such as row/column summation and resistor-based readout. These features are greatly sought after in readout electronics for the SiPMbased radiation detectors. Experimental results show that the proposed highly-integrated electronics system overcomes the bottleneck that has limited the development of advanced PET detectors and scanners.

A plastic scintillating fiber (SciFi) detector with one-dimensional highly segmented silicon photomultipliers (SiPMs) readout can achieve much finer spatial resolution than conventional bulk plastic scintillator detectors. In this work, to construct a large-area SciFi detector for muon scattering tomography, a compact multi-channel front-end electronics is developed based on Citiroc1A, a SiPM readout chip. This electronics system includes an analog board with Citiroc1A for interfacing SiPM arrays, and a digital board with Analog-to-Digital Converter, Field Programmable Gate Array and optical communication modules. We realized primary functions of Citiroc1A and evaluated the system performance on pedestal and pulse response. This front-end electronics design enables to identify a single photoelectron pulse of SiPMs and provide a linear response range up to about 300 pC, which satisfies the requirements of registering cosmic ray muons in the SciFi detector.

The recent discovery of PeV gamma-ray emission especially from the LHAASO observatory, located in the Northern hemisphere, boosted the relevance of observing the Southern sky at such energies. SWGO (SouthernWide-Field Gamma-Ray Observatory) is the largest proposed detector with sensitivity in the 100 TeV-1 PeV energy range. The baseline SWGO idea is a km^2 array of water tanks to be placed above 4,400ma.s.l. in the Andes, South America. In this contribution, we have studied the particle content and the morphology of Extensive Air Showers (EAS) generated by photons and protons in the 0.1 to 10 PeV energy range. We have simulated over 106 gamma-rays and proton induced showers respectively with primary energy in the 0.1-10 PeV energy range. We also show the particle distribution at ground, the lateral profile, the muon content and the average particle properties at ground.

Introduction: Nowadays, attention is growing on the Silicon Photomultipliers (SiPMs) detector for many applications, especially in nuclear medicine. In Positron Emission Tomography (PET) scanner, timing performance of a PET detector plays a significant role in image reconstruction.Methods: This work mainly aims at the processing of timing signal for the purpose of achieving a good timing performance. We applied a timing detector made up of a 3 × 3 × 10 mm3 LYSO crystal directly coupled with a large-size SensL SiPM with a sensitive area of 6 × 6 mm2. The standard output of the SiPM was used for energy calculation while the fast output was for timing pickoff. Three different readout configurations for fast timing signals were used for timing performance evaluation: 1) the recommended RF transformer-based readout, 2) the cascaded Common Emitter Amplifier (CEA), 3) the commercial RF amplifier.Results: Experiment results show that the best FWHM CTR values for the three were 228.3 ± 1.4 ps, 235.4 ± 1.1 ps and 231.1 ± 1.5 ps for the RF transformer-based, the CEA-based and the RF amplifier-based readout configurations respectively. The schemes based on the CEA-based and the RF amplifier-based configurations have a good uniformity at different trigger thresholds.Discussion: For practical application, the amplified timing signal based on the CEA circuit is more desirable because it is more feasible for trigger threshold selection in multichannel readout electronics system.

The SWGO Collaboration is evaluating the possibility of deploying Water Cherenkov Detectors (WCD) in a high-altitude natural lake. For that, the first challenge is to build a bladder strong enough that could be used as a WCD inside a natural lake. A prototype bladder has been designed for SWGO and two bladders, made of different films, have been deployed for testing at Sibinacocha lake, in Peru, at 5000 masl. In order to monitor the wave intensity in the lake, a low-cost oceanographic buoy was developed using an acceleration sensor MPU6050 and a liquid sensor DS18B20. The development platform used was the Arduino Mega 2560 with some out-of-the shelf modules to achieve a functional and autonomous prototype. A code was developed in Python to process the data and convert the acceleration values into position, allowing estimation of height variations, as a function of time, less than 1 cm. To reduce the environmental impact of the floating structure, the use of metallic materials was minimized and mostly wood, cotton, and PVC pipes were used. This buoy has been installed next to SWGO prototype bladders at the Sibinacocha lake in Peru. In this contribution we will present the details of a low-cost oceanographic buoy built to monitor lake wave intensity.

Current cosmic ray anisotropy experiments have shown a significant swing in both the direction and the amplitude of the dipole at energies around tens of TeV. Due to the charged nature of these particles, and the presence of magnetic fields in our galaxy, an underlying composition-dependent dipole swing is expected. For this reason, combining measurements of the composition and the distribution of arrival directions is essential for unveiling the astrophysical origin of this structure. In this work, we study the potential of the upcoming Southern Wide-field Gamma-ray Observatory (SWGO) in contributing to these anisotropy studies. We present a template-based method developed for reconstructing the number of muons and separating primary cosmic rays. Preliminary resolutions of $5-30\%$ in the number of muons and an accuracy of $70-90\%$ in the species separation are found. A clear improvement is seen by considering a dedicated muon-counter layer in a detector, highlighting the future potential of SWGO.

With the development of silicon photomultiplier (SiPM) technology, front-end electronics for SiPM signal processing have been highly sought after in various fields. A compact 64-channel front-end electronics (FEE) system achieved by field-programmable gate array-based charge-to-digital converter (FPGA-QDC) technology was built and developed. The FEE consists of an analog board and FPGA board. The analog board incorporates commercial amplifiers, resistors, and capacitors. The FPGA board is composed of a low-cost FPGA. The electronics performance of the FEE was evaluated in terms of noise, linearity, and uniformity. A positron emission tomography (PET) detector with three different readout configurations was designed to validate the readout capability of the FEE for SiPM-based detectors. The PET detector was made of a 15 × 15 lutetium–yttrium oxyorthosilicate (LYSO) crystal array directly coupled with a SiPM array detector. The experimental results show that FEE can process dual-polarity charge signals from the SiPM detectors. In addition, it shows a good energy resolution for 511-keV gamma photons under the dual-end readout for the LYSO crystal array irradiated by a Na-22 source. Overall, the FEE based on FPGA-QDC shows promise for application in SiPM-based radiation detectors.

A field programmable gate array (FPGA) voltage-referenced standard receiver based charge-to-digital converter (QDC) was proposed. The QDC is based on a linear discharge scheme. In the linear discharge circuit, typically, a low-voltage differential signaling (LVDS) receiver serves as a voltage comparator. Our proposed scheme takes advantage of voltage-referenced standard in the FPGA instead of the LVDS standard, which maximizes the capability of multichannel and multifunctionality. The linearity differences were compared between the voltage-referenced receivers and the LVDS receiver. To validate the scheme for radiation detector application, a 32-channel electronics prototype based on the proposed structure was developed. A positron emission tomography (PET) detector module was built. The detector is made up of a 15 $\times $ 15 LYSO array directly coupled with two silicon photomultipliers (SiPM) at two ends. The mean energy resolution for single crystal at the center can reach 17.9%. The linear discharge scheme based on voltage-referenced receivers provides a promising method for a compact, multichannel electronics readout system for radiation detector application.