The CSR External-target Experiment (CEE) is a large-scale spectrometer under construction at Lanzhou's Heavy Ion Research Facility (HIRFL), focusing on studying nuclear matter's phase structure (high baryon density) and equation of state (supra-saturation densities). Its key component is a large-acceptance dipole magnet: 0.5 T central field, 5% homogeneity within a 1m & times;1.2 m & times;0.9 m aperture (for detectors). An innovative superconducting magnet design is proposed: coil-dominant type with racetrack-shaped discrete conductors, plus a warm iron yoke (enhances central field, reduces stray field). The magnet is 3.4 m long, 2.7 m high, 4.3 m wide. Coils use 19-strand cables, supported by keels to withstand electromagnetic force. Due to its novel structure, the magnet scheme poses great technical challenges. Therefore, a 1/6-scale prototype magnet was developed to comprehensively verify the scheme's feasibility via the scaled-down prototype. This paper will detail the development process of this scaled-down magnet prototype.

Fast-ramping superconducting magnets are crucial for the next-generation high-intensity heavy-ion accelerators and cancer therapy machines. A fast-ramping superconducting dipole magnet featuring a multi-layer coil structure has been developed at the Institute of Modern Physics (IMP), Chinese Academy of Sciences. This magnet utilizes a modified cos theta configuration with rope-based cables. It consists of an 8-layer coil wound with two types of rope cables to improve conductor utilization efficiency. The coil layout was optimized through a linear programming algorithm. To reduce AC losses during fast-ramping operations, low-loss NbTi strands with CuMn matrix were employed, along with G10 formers. The magnet was optimized by integrating liquid helium channels and interlayer copper strips to enhanced heat conduction, based on AC loss estimates and thermal simulations. A shell-based structure utilizing bladder and key technology was employed to pre-stress the superconducting coils. An 800 mm-long dipole prototype was manufactured, assembled, and tested in liquid helium. After 76 quenches, the dipole prototype achieved a central magnetic field of 6 T and a maximum ramp rate of 1.01 T/s. This paper presents the design, fabrication, assembly, and test results of the prototype dipole magnet.

The High Energy Photon Source (HEPS) Linac is a normal-conducting electron linear accelerator capable of producing high bunch charge beam. Its bunching system includes two subharmonic bunchers (SHBs), one prebuncher, one buncher, and one accelerating structure. The SHB is commonly used in the low-energy section for longitudinal bunching to increase the bunch charge. The phase and voltage of the SHB are crucial for obtaining a high-quality electron beam in Linac. This paper presents a method for calibrating the phase and voltage of the SHB using the time-of-flight technique. Experiments were conducted at the HEPS Linac using two beam position monitors. According to the simulations, we found that bunch length and space charge effect have a significant impact on the results, and we propose corrective measures to address them. To enhance experimental efficiency, we propose a data processing method called the truncated averaging technique that eliminates the need for corrective measures, which has been validated through both simulations and experiments, yielding outstanding results. This paper presents detailed insights into both the simulation and experimental procedures.

Fe-based nanocrystalline materials is a typical soft-magnetic material with advantages such as high saturated magnetic flux, high resistivity and low magnetostriction coefficient. By utilizing a specialized winding process, the ultra-thin strip has been successfully applied for use in scanning magnetic cores. For static field, the simulated and tested integral magnetic field uniformity is consistent, and tested effective length is slightly shorter than simulated one. The static magnetic field can meet the needs of scanning magnets. For transient field, the new iron core has less magnetic field delay and distortion compared to silicon steel sheet iron. The simulated maximum magnetic field delay is reduced from 161 Gauss to 16 Gauss. The maximum magnetic field delay of silicon steel sheet iron under test is 87 Gauss, and the corresponding data of the new iron core is almost 0 Gauss. With the weakening of the magnetic field delay, the magnetic field distortion should also be suppressed. With the novel iron core, the magnetic field of the scanning magnet can be improved, thereby reducing the distance from the scanning magnet to the terminal. Rotating gantry is the focus of current research on proton and heavy ion therapy accelerator facilities. This novel iron core can facilitate a decrease in the rotating diameter and weight of the gantry, while enhancing the scanning accuracy. Moreover, the novel iron core can be exploited in scenarios where ferrite cores are “excess capacity”, but traditional silicon steel cores are “insufficient capacity”, such as for certain bump magnets used in synchrotrons.

A superconducting fast cycling dipole prototype with a central field of 6 T and ramp rate of 1 T/s for ion synchrotron is currently under development at Institute of Modern Physics (IMP). The magnet utilizes a modified cos θ coil design, employing multi-strand round cable in formed grooves. The ribs of straight section of the coil formers have been removed to improve the excitation efficiency. Low loss round cables, made from NbTi/CuMn superconducting wires with a filament of 4.1 um, and the G10 formers are used to reduce AC losses during the ramping operation. The copper cold conduction strips are arranged between layers to improve the cooling efficiency. Bladder and key technology is adopted to prestress the coils. 2D layout of the coil is obtained through a linear programming code. This paper presents the round cable design, 2D cross section optimization, coil end and mechanical design, thermal analysis of the magnet, as well as the development of a technical prototype.

HIAF (High Intensity heavy ion Accelerator Facility) is a new generation heavy ion accelerator under construction in China. The HFRS (FRagment Separator of HIAF) is a fragment separator and also a transfer-line between the Booster Ring and the Spectrometer ring. HFRS magnet system is composed of 11 superconducting dipoles and 13 sets of triplets. The dipole magnets adopt a super-ferric scheme. The requirement for the dipole magnets is a large acceptance at moderate fields, which can be fulfilled by super-ferric magnets with wide apertures. The magnetic field ranges from 0.2 T to 1.6 T with a bending radius of 15.7 m and a bending angle of 10°. A homogeneous dipole magnet field shape is required in the good field region of x ±160; y ±70 mm. This paper presents a detailed design and optimization of the magnet based on a multi-parametric model. The integral field homogeneity is optimized by an automatic chamfering algorithm. According to the installation conditions of the HIAF-HFRS, the magnet adopts a block processing and assembly method, which is manufactured and assembled by 14 blocks. The first set of the magnets has been completed and tested, and the test results are better than the design indicators.

Purpose The physics design of the High Energy Photon Source (HEPS) was finished after many times of iteration. Hereby, the typical equilibrium electron beam parameters corresponding to the proposed two baseline operation modes in the baseline design of HEPS are presented. Methods To compute the equilibrium parameters of the electron beam, the lattice parameters, RF parameters, and the parameters of the insertion devices (IDs) were determined first. Furthermore, it is more precise to use the full-current electron beam parameters in the estimations of the performance of the synchrotron light. Therefore, not only the single-particle dynamics but also the current-dependent collective effects need to be considered in the computations of the full-current, equilibrium parameters of the electron beam. Both analytic computations and multi-particle tracking simulations were carried out. Results The full-current, equilibrium parameters of the electron beams in the HEPS storage ring are presented in this paper. Moreover, the main beam parameters in the injector (the booster and the LINAC), corresponding to the two baseline operation modes of the storage ring, are also presented. Conclusion The typical electron beam parameters corresponding to the two baseline operation modes are given in detail in this paper.

Effects of hot pixels on pixel performance in light and dark environments have been investigated in pinned photodiode 0.18 μm backside illuminated CMOS image sensors irradiated by 10 MeV protons. After exposure to protons, hot pixels and normal pixels are selected from the whole pixel array, and their influences on key parameters are analyzed. Experimental results show that radiation-induced hot pixels have a significant impact on pixel performance in dark environments, such as dark signal nonuniformity, long integration time, and random telegraph signal. Hot pixels are caused by defects with complex structures, i.e., cluster defects. Furthermore, the dark current activation energy result confirms that the defects causing the hot pixels have defect energy levels close to mid-gap.

The superferric superconducting dipoles are designed for the High energy FRagment Separator (HFRS) of the Heavy-ion Accelerator Facility (HIAF) in China. The dipole magnets of the separator will have a deflection radius of 15.7 m, a field up to 1.6 T with a ± 160mm ×± 62mm good field region and an effective length of 2.74 meters. In the HIAF-HFRS, there will be a total of 11 superferric dipoles under construction. The dipole consists of two superconducting coils, a coil casing, a cryostat, and a warm iron yoke. The superconducting coils are protected by the scheme of quench detection and energy-extraction. At present, the first prototype dipole has been fabricated and tested, which reaches the design current of 210 A without a quench and the magnetic field of 1.64 T at the good field area, meeting the physical requirements. The measured results of magnetic field and energy discharge behaviors are in good agreement with the calculations. This paper describes the details of mechanical design, construction and the testing results of the prototype.

High frequency and magnetic rigidity are the requirement of accelerators for scanning magnets. The scanning magnets for the SESRI (the Space Environment Simulation and Research Infrastructure) project are excited by triangular currents with a maximum repetition frequency of 200 Hz. It is inevitable to produce eddy currents inside the iron yoke, especially at the pole end. The temperature rise will be caused by eddy current loss, damaging the insulation layer in coils and adhesive resin in the core. To ensure the successful design and long working life for the scanning magnet, it is essential to optimize the eddy-current losses and temperature rise. This paper provides the optimization method for the scanning magnet, describes the analysis method of eddy-current loss induced temperature rise in detail, and then the distribution of the eddy current and temperature on the yoke is calculated by the software of OPERA-ELEKTRA/TR. Meanwhile, the temperatures at some critical points of the scanning magnet were measured. The computed results verified the feasibility of the electromagnetic-thermal coupling analysis method, which agreed well with the experimental data.

Effective network security management is usually based on comprehensive, accurate and real-time control of enterprise network. With the rapid growth of enterprise network information, their exposure on the Internet is also expanding rapidly, which raises many security issues. It is hard for the existing approaches of network security management to cover dynamic and hidden assets. Moreover, black-box-based network reconnaissance is highly dependent on expert experience and time-consuming, which cannot meet the needs of enterprises to perform testing periodically. Therefore, target-oriented automated reconnaissance of network information becomes an urgent problem to be solved. We proposed and constructed a knowledge graph based network reconnaissance model, NRG, from a method-level perspective which describes the relationship between different network information and the way to reconnaissance them. Based on NRG, we have designed and implemented Auto-Recon, an automated network reconnaissance system using the distributed architecture. The purpose of Auto-Recon is to automatically find exposed surfaces of targets on the Internet using the primary domain as initial information. The system reduces strong dependence on network reconnaissance knowledge and experience. We conducted an experiment and the result shows that Auto-Recon has better performance in terms of efficiency, effectiveness and automation than existing tools.

The electron cooling technology is applied in the spectrometer ring (SRing) to improve the luminosity of ion beam for the High Intensity heavy-ion Accelerator Facility (HIAF). The electron cooler consists of a gun section, two 90-degree toroids, a cooling section and a collector section. There are four kinds of main coils used to provide longitudinal magnetic fields along the path of the electron beam. In this paper, we present the modeling and analyzing of the electron cooler magnets by three-dimension software. The optimizing of the magnetic field of cooling section is completed to achieve the required effective cooling length. The magnetic fields along the electron beam path and ion beam path are calculated and the beam trajectory of typical ion is also simulated to offer data for correcting the orbit.

The Institute of Modern Physics (IMP) has developed a magnetic measurement system of the triplet quadrupoles in drift tube linac (DTL), based on the rotating coil method. The most important measurement requirement of the triplet in DTL is the deviation between the machinery axis of the cavity and the magnetic axis of the triplet quadrupoles, which is less than 0.1 mm, the angle deviation is less than 1 mrad. The magnetic field quality is also measured. There are two aspects to be considered when designing the system, one is the mechanical adjustment mechanisms for the three quadrupoles respectively, another is the specialized compensated coil consisting of two sets of windings which can be connected to measure the magnetic center and the high order harmonic errors. Simultaneously, optimizing the testing process is also crucial. Based on the results obtained on the two triplets in two tanks for a Heavy Ion Medical Machine with Linear Accelerator (HIMM-LINAC), the magnetic measurement system could meet the requirements

The purpose of this work is to investigate the influence of the epitaxial layer thickness of Backside-illuminated CMOS image sensors (BSI CISs) on dark signal behaviors. BSI CISs with the high quantum efficiency and sensitivity were irradiated by 1 MeV neutron up to the fluences of 109 cm-2. The displacement damage induced variations of the mean dark signal, Dark signal nonuniformity (DSNU), dark signal spikes and Random telegraph signal (RTS) on the different epitaxial layer thicknesses are analyzed. The experimental results show that there is no obvious correlation between the degradations of dark signal parameters and the epitaxial layer thickness, suggesting that the electric-optical performance of BSI CISs can be improved by optimizing the epitaxial layer thickness.

CMOS image sensors were irradiated by protons of 50 and 70 MeV and the dark current random telegraph signal (RTS) is investigated. After exposure to the protons, the experimental results provide new evidence that confirms the existence of a correlation between radiation-induced hot pixels and RTS pixels. Moreover, the evolutions of the percentage of hot pixels showing RTS behavior at distinct conditions are presented, suggesting the different dependence of two kinds of pixels on operation conditions. The results of the isochronal annealing experiment demonstrate that the defects responsible for RTS behavior are the cluster defects able to enhance thermal generation through Shockley-Read-Hall (SRH) mechanism.

As mainstream optical imaging electronic devices, image sensors are widely used in space missions under complex radiation environments. This study investigated the effects 60 and 10 MeV proton irradiations on dark current, dark signal non-uniformity (DSNU), and photon response non-uniformity (PRNU) for a commercial global shutter 8T complementary metal-oxide semiconductor (CMOS) image sensor. A fluence range from 9 x 10(9) p/cm(2) to 7.26 x 10(10) p/cm(2) was considered. The total ionizing dose deposited reached 10 krad (Si), which significantly increased the dark current. DSNU and PRNU also followed a similar trend with an increase in the dose, which is based on the effects of the total dose and displacement damage. After irradiation, a TCAD simulation was conducted to identify the radiation-induced defects. The results showed that the trapped positive charges in the oxides, interface states in the Si/SiO2 interface, and bulk defects in a pinned photodiode depleted region significantly increased the dark current. The outcomes of this study form significant reference for advancements in radiation-hardened image sensor designs.

The degradation of a pinned photodiode (PPD) 8T CMOS image sensor (8T-CIS) due to total ionizing dose (TID) and displacement damage dose (DDD) have been investigated with ?-ray and proton irradiation. The dark current and its distributions were studied. We observed a significant increase in the dark current after the proton irradiation than that after the ?-ray irradiation. We observed that the peak values in the Gaussian distribution shift to higher values as a result of TID effects while comparing the dark current distribution results of the ?-ray and proton irradiation. In contrast, the hot pixel tailing increases with the DDD effect. At the same time, the degradation of the light response of the device was investigated by observing the quantum efficiency in the wavelength range of 420?800 nm. A comparison of the results obtained from the ?-ray and proton irradiations showed that the short-wavelength degradation was caused by the TID whereas the DDD caused the degradation in the full spectral range.

The dark current random telegraph signal (DC-RTS) has been investigated in a four-transistor pinned photodiode 0.18-μm backside illuminated CMOS image sensor (BSI CIS). The sensors were irradiated by high energy protons of 50, 60 and 70 MeV, respectively. After exposure to protons, the radiation-induced variations of the number of RTS pixels, the number of RTS levels and transition maximum amplitude are analyzed. The effect of proton energy on RTS occurrence probability is studied using two types of theoretical models. Furthermore, DC-RTS dependence on the epitaxial layer thickness of the sensors is discussed, showing that there is no significant difference for DC-RTS phenomenon in different epitaxial layers.

Single-event transient (SET) and single-event latchup (SEL) of a 4T pinned photodiode (PPD) complementary metal-oxide-semiconductor (CMOS) image sensor (CIS) fabricated with a 0.18-mu m CMOS process were investigated using heavy ions and a picosecond pulsed laser. The SET bright spot characteristics were further studied, and the transient bright spots formed by laser and heavy ions were analyzed. The sensor exhibited SELs and micro-SEL. To determine the precise sensitive location where SEL occurred in the CIS, a pulsed laser with a 2-mu m beam spot was used to scan the entire surface of the device. The results revealed that SEL occurred in the peripheral circuits of the CIS, including the analog signal processing circuit, row-addressing circuit, and analog-to-digital conversion (ADC). The cross section of the SELs for the sample were measured using a linear energy transfer (LET) ranging from 8.62 to 81.35 MeV.cm(2) mg(-1). The SEL rates in space for the used CIS were predicted using the CREME96 tool.

Charge coupled devices with high sensitivity and low dark current were irradiated separately by 10 MeV proton, 14 and 1 MeV neutron up to the fluences of 10(9) cm(-)(2). The generation pattern of hot pixels at different conditions is presented. The experimental results demonstrate that the nuclear inelastic scattering is the dominant generation mechanism of hot pixels induced by proton and neutron irradiations. Meanwhile, a theoretical model is used to predict hot pixel tails at different annealing time points and different operating temperatures.