Subjects: Nuclear Science and Technology >> Nuclear Detection Technology and Nuclear Electronics submitted time 2024-04-19
Abstract: In order to meet the demand for elementary particle detection and analysis in high-energy physics experiments, modern pixel detector increasingly tends to pursue the performance requirements of low power consumption, high resolution, and high readout efficiency.This paper describes a silicon pixel detector digital-analogue hybrid readout chip named IMPix-N1. The pixel array consists of 16 rows × 16 columns of pixel units, each with an area of 100 μm × 100 μm, and the pixel array part is controlled by a 1-row × 8-column pixel unit as a superpixel, which has a common logic circuit. The chip has a pixel configuration mode and three pixel address readout modes of operation, which realises the measurement, storage and readout of the time, energy and position information of the hitting particles. The time-to-digital conversion circuit (TDC) can simultaneously measure and record the arrival time TOA and the over-threshold time TOT of the particles, with a time measurement accuracy of 5 ns. The IMPix-N1 is suitable for particle detection experiments requiring high temporal and spatial resolution as well as fast data acquisition capabilities.The chip as a whole is designed using the digital-on-top methodology in TSMC 180nm process. The design is simulated to verify the digital circuit of the pixel unit, the super pixel control circuit and the peripheral digital circuits, and the before and after simulation results are consistent and meet the design requirements.
Subjects: Nuclear Science and Technology >> Radiation Physics and Technology submitted time 2024-04-08
Abstract: For the superconducting linac section of the Chinese Accelerator Driven Transmutation Research facility (CiADS) operating in continuous wave (CW) mode, the effect of cavity detuning caused by fluctuations of liquid helium pressure is an important factors for stable operation of low β cavities. Aiming at the phenomenon of unstable operation of half-wave superconducting resonators affected by helium pressure fluctuations, and taking the half-wave superconducting resonator with a frequency of 162.5 MHz and an optimal beta of 0.19(HWR019) applied in CiADS superconducting linac section as an example, the fluctuation of liquid helium pressure and the frequency variation law of the cavity was simulated with the method of numerical simulation. By calculating and analyzing the relationship between the contact area of liquid helium in the cavity, the wall thickness of the cavity, the shape of the liquid helium cooling channel, and the helium pressure sensitivity coefficient (KPress) of the cavity, the goal of reducing the (KPress) value of the HWR019 superconducting cavity to close to 0 was achieved, which effectively ensures the stable operation of the superconducting cavity in CiADS. At the same time, by conducting thermodynamic calculations on the cavity, corresponding enhanced heat transfer schemes were provided, effectively reducing the maximum temperature of the superconducting cavity during operation. The analysis and optimization methods also have reference significance for the same type of low β superconducting cavities.
Subjects: Nuclear Science and Technology >> Nuclear Detection Technology and Nuclear Electronics submitted time 2024-01-22
Abstract: Based on a UMC 55 nm CMOS process, this paper implements a 10 GHz high-performance charge pump phase-locked loop with high-speed output and low power consumption, which can provide a high-frequency differential clock for the data transmission system in particle physics experiments. A dual-branch charge pump with an operational amplifier and dummy MOSFETs is designed to reduce the influence of non-ideal factors on the circuit. A high-speed, low-power 64-divider circuit is designed to convert the 10 GHz differential clock output by the phase-locked loop into a 156.25MHz single-ended clock. An LC voltage-controlled oscillator is designed with a complementary cross-coupled structure, which enables fast start-up with low phase noise. The simulation results show that under the typical process corner, the phase noise of the VCO at 1 MHz frequency offset is -104.14 dBc/Hz. The PLL lock time is about 500ns, the power consumption is 22.34mW, and the peak-to-peak jitter is 6.59ps.
Subjects: Physics >> Nuclear Physics submitted time 2023-11-03
Abstract: Multinucleon transfer reactions involving heavy actinide projectile and target nuclei hold significant potential as a groundbreaking method to synthesize
neutron-rich superheavy nuclei. The construction of a Principled Spectrometer for Neutron-rich Superheavy Nucleus Research is highly desirable to establish the technical, methodological, and device foundation to explore the stability island in superheavy nuclei and to study the mechanism of multinucleon transfer reactions. The gas cell of the Principled Spectrometer requires a continuous supply of high-purity helium gas to stop the energetic radioactive reaction products and to extract the energy-reduced ions to the subsequent experimental setup. The paper focuses on a newly developed cryogenic purification system for the gas cell of the spectrometer. This cryogenic purification system is designed to provide recyclable and high-purity helium for the Principled Spectrometer. With a series of tests, the cryogenic purification system has been proven to be able to purify the 99% helium gas to 99.999% or higher, fulfilling the requirements of the gas cell when used in conjunction with the chemical purification system.