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The study of nuclide production and its properties in the N=126neutron-rich region is prevalent in nuclear physics and astrophysics research. The upcoming High-energy FRagment Separator (HFRS) at the High-Intensity heavy-ion Accelerator Facility (HIAF), an in-flight separator at relativistic energies, is characterized by high beam intensity, large ion-optical acceptance, high magnetic rigidity, and high momentum resolution power. This provides an opportunity to study the production and properties of neutron-rich nuclei around N=126. In this paper, an experimental scheme is proposed to produce neutron-rich nuclei around N=126and simultaneously measure their mass and lifetime based on the HFRS separator; the feasibility of this scheme is evaluated through simulations. The results show that under the high-resolution optical mode, many new neutron-rich nuclei approaching the r-process abundance peak around A=195can be produced for the first time, and many nuclei with unknown masses and lifetimes can be produced with high statistics. Using the time-of-flight corrected by the measured dispersive position and energy loss information, the cocktails produced from 208Pb fragmentation can be unambiguously identified. Moreover, the masses of some neutron-rich nuclei near N=126can be measured with high precision using the time-of-flight magnetic rigidity technique. This indicates that the HIAF-HFRS facility has the potential for the production and property research of neutron-rich nuclei around N=126, which is of great significance for expanding the chart of nuclides, developing nuclear theories, and understanding the origin of heavy elements in the universe.

The fracsparameterizations, labeled as fracs-c, have been improved in order to predict the presence of isotopes near the proton drip line produced in projectile fragmentation reactions. By investigating the cross sections for proton-rich isotopes in a series of reactions with energies ranging from intermediate to relativistic, it is shown that the fracs-cparameterizations can predict isotopes near the proton drip line considerably well. The fracs-cparameterizations are suggested to serve as an effective tool for predicting the presence of proton-rich isotopes with large asymmetry in a projectile fragmentation reaction. Different reactions have been investigated to check these results.

We propose a system for remote measurement of low-energy radiation, which is implemented using an ARM board and a ZigBee module. The ARM STM32F103 board employs a horizontal and vertical moving CMOS camera for front-end data acquisition. The camera can detect radiation over different coordinates given by latitude and longitude in a determined area. For image processing, we used the subtraction–summation algorithm based on gradient multiplication and edge detection. Compared to algorithms such as the max grayscale value, subtraction–summation, and whole summation, the improved subtraction–summation algorithm filters noise and removes the background grayscale value of the whole image to attain higher accuracy, stronger anti-interference ability, and better consistency to determine the radiation dose. We dedicated one port of the transmission module to send data through the STM32F103 board, whereas another port is connected to the ZigBee module for data reception. By employing this architecture, we achieved low power consumption and fast response in the remote data transmission. Overall, the proposed system performs the remote measurement of low-energy radiation with stability and reliability, which is required for critical scenarios such as the remote detection of nuclear radiation.

Modern rare isotope beam (RIB) factories will significantly enhance the production of extremely rare isotopes (ERI) at or near drip lines. As one of the most important methods employed in RIB factories, the production of ERIs in projectile fragmentation reactions should be theoretically improved to provide better guidance for experimental research. The cross-sections of ERIs produced in 140 MeV/u 78,86Kr/58,64Ni/40,48Ca + 9Be projectile fragmentation reactions were predicted using the newly proposed models [i.e., Bayesian neural network (BNN), BNN + FRACS, and FRACS, see Chin. Phys. C, 46: 074104 (2022)] and the frequently used EPAX3 model. With a minimum cross-section of 10-15mb, the possibilities of ERIs discovery in a new facility for rare isotope beams (FRIB) are discussed.

The neutron capture cross section of 197Auwas measured using the time-of-flight (TOF) technique at the Back-n facility of the China Spallation Neutron Source (CSNS) in the 1 eV to 100 keV range. Prompt γ-rays originating from neutron-induced capture events were detected by four C6D6liquid scintillator detectors. Pulse height weighting technology (PHWT) was used to analyze the data. The results are in good agreement with ENDF/B-VIII.0, CENDL-3.1, and other evaluated libraries in the resonance region, and in agreement with both n_TOF and GELINA experimental data in the 5–100 keV range. Finally, the resonance peaks in the energy range from 1 eV to 1 keV were fitted by the SAMMY R-matrix code.