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Purpose: Glass is a potential choice for the scintillator in Hadronic calorimetry (HCAL) of the CEPC. It requires sophisticated instruments and suitable methods to obtain scintillation properties of the glasses in the first time. It is necessary to establish an evaluation method for nuclear radiation detection performance of glass scintillator. Methods: The spectroscopy research of the glass includes transmission/absorption spectrum and emission spectrum. The time characteristics include rise time, scintillation decay time and afterglow. The scintillation properties include light yield, energy resolution and minimum ionizing particle (MIP) response. And a new method for measuring the low light yield of glass scintillators is proposed. Results: We have built a complete performance test system and evaluation method, which can evaluate the nuclear radiation detection performance of different glass scintillators. Conclusion: By continuously improving the composition and preparation process of the glass, it can provide potential possibilities for the application in the high-energy physics experiment and nuclear radiation detection fields.

In this work, a strategy of manipulating the cerium activator concentration was adopted to enhance the n/γ discrimination and luminescent thermal stability of Cs2LiLaBr6(CLLB). CLLB single crystals doped different cerium concentrations with a size of Φ12 mm × 50 mm were grown by the Bridgman method. The crystal structure and actual concentration of Ce3+were determined by the XRD and ICP-AES methods. The effects of cerium doping amount on the luminescence properties, thermo-stability, scintillation properties, and n/γ discrimination capability were systematically investigated. Compared with the low Ce3+concentration doping (1 and 2 mol %), the higher concentration crystal (10 mol %) presents a better n/γ discrimination capability with a high figure-of-merit of 2.1, which is the optimum result for the CLLB:Ce crystal. It is important that the thermal quenching temperature T(50)of CLLB:10 mol % Ce crystal is higher than 460 K when the CLLB:1 % Ce crystal is about 340 K. It shows a potential application in the field of extreme environments.

A 1-in Cs2LiYCl6:Ce (CLYC) scintillator coupled with Photomultiplier tube (PMT) was used to detect neutrons and gamma rays simultaneously in this work. The pulses were captured by a high-speed digitizer with 1-Gsamples per second and 12-bit vertical resolution and further analyzed in real time to determine the pulse type, energy spectrum, and flux. The response of CLYC scintillators measured with three PMT models, R6231 and XP2020, were found to have better energy resolution, while R580 was found to have better pulse shape discrimination (PSD) performance. The energy resolution was optimized by adjusting the integration time window. Slight differences were found to be within the range of 2000–8000 ns for different PMT models. The fast neutron peaks from 35Cl(n, p)35S reaction were detected along with the thermal neutron peak from 6Li(n, $\alpha)^{3}\text{H}$ , and a quenching factor of 0.9 was obtained for protons. The energy resolution was 14.7% and the detection efficiency was about 0.15% for 1.5-MeV fast neutron. The discrimination performance between neutron and gamma pulses was studied using the charge comparison method. The figure-of-merit (FOM) value was found to be better than 1.90 within the energy range of 0.5–10 MeV, i.e., 2.0 for 1.5-MeV fast neutron and ~3.2 for thermal neutron. The flux of fast neutrons, thermal neutrons, and gamma rays was detected simultaneously, and the prompt gamma rays by neutron activation were also identified. It indicates that the CLYC detector can be used for multimode detection of thermal neutrons, fast neutrons, and gamma rays, and would be a suitable compact candidate for prompt gamma neutron activation (PGNAA) analysis in limited space.

The timing information carried by the photomultiplier tube (PMT) waveform is important when reconstructing the particle trajectory, especially in the application of time-of-flight detectors. The traditionally used timing methods, including leading edge discrimination (LED) and constant fraction discrimination (CFD), are easily realized in the circuit. Since the timing point of the signal should be determined by the whole signal waveform, the CFD and LED method cannot reach the best time resolution. With the development of a fast analog-to-digital converter (FADC) which makes the whole waveform available, more intelligent methods are developed to realize more precise timing. Former studies show that PMT-waveform-analysis model based on convolutional neural network (CNN) can improve the coincidence time resolution (CTR) of a pair of PMTs by nearly 20%, but the limit of number of labels directly affects the CNN timing performance. In this article, a new method based on the CNN model is introduced for the timing of a pair of Cherenkov-detection micro-channel-plate PMTs (MCP-PMTs). The results show a great improvement compared with the CFD method.

The double crystal diffraction structure based on Bragg diffraction is the core component of the monochromator that is widely used in synchrotron radiation beam lines and monochromatic X-ray radiation devices. The stability of monochromatic X-rays produced by using the T-structure double crystal monochromator at National Institute of Metrology was investigated experimentally. Due to its structural defects, the X-ray flux of the T-structured double crystal monochromator shows poor long-term stability. Inspired by the Channel-cut monochromator structure, we designed a new double crystal monochromator structure to improve the long-term stability of the X-ray flux. Experiments showed that the stability of the monochromatic X-ray flux for the new double crystal monochromator structure was better than 1.0%@1 h, and the energy region and flux rate of the monochromatic X-rays are significantly improved. This work provides a stable and reliable monochromatic X-ray source for the calibration of X/γ detectors such as satellite load detectors, which will contribute to the development of X/γ detection technology.

Single-event upset (SEU) is investigated using heavy ion and pulsed laser. The measured SEU cross sections of D and DICE flip-flops are compared. Measurement results indicate pulsed laser is capable of inducing similar SEU to those induced by heavy ion. 3D-TCAD simulation is performed to investigate the factors to impact pulsed laser induced SEU. Simulation results show that the beam spot size significantly impacts SEU cross sections in both low and high laser energy while the variation of the equivalent LET only impacts SEU cross sections in the low laser energy.

The internal single-event transient (SET) induced upset in flip-flops is becoming significant with the increase of the operating frequency. However, the conventional soft error rate (SER) evaluation approach could only produce an approximate upset prediction result caused by the internal SET. In this paper, we propose an improved SER evaluation approach based on Monte Carlo simulation. A novel SET-based upset model is implemented in the proposed evaluation approach to accurately predict upsets caused by the internal SET. A test chip was fabricated in a commercial 65 nm bulk process to validate the accuracy of the improved SER evaluation approach. The predicted single-event upset cross-sections are consistent with the experimental data.

Internal SET has become a great concern in normal radiation-hardened flip-flops with increases in frequency. We investigate the internal SET problem in the traditional hardened flip-flops in this article. We also propose a novel structure to eliminate the internal SET problem. Three-dimensional technology computer-aided design (TCAD) was adopted to verify the hardened performance of this proposed novel structure. Besides, the power and setup time were compared with the traditional hardened flip-flops.