## 2021年  第38卷  第4期

2021, 38(4): 1-2.

2021, 38(4): 361-367. doi: 10.11804/NuclPhysRev.38.2021076

r-过程等待点原子核的β衰变半衰期对研究宇宙中重元素起源有重要意义。质子-中子准粒子无规相位近似(pn-QRPA)是研究原子核β衰变的重要理论模型。本工作提出了一个改进的 pn-QRPA 模型，系统研究了满壳附近原子核的 β 衰变性质。与之前的工作相比，改进的模型采用了中子数和质子数依赖的新粒子-粒子和粒子-空穴相互作用形式。本工作首先计算了满壳附近一些已知原子核的 β衰变半衰期和 Gamow-Teller 强度分布，发现理论结果与实验数据符合较好，检验了新模型的可靠性。随后，理论预测了 \begin{document}$N=50$\end{document}, \begin{document}$N=82$\end{document}\begin{document}$N=126$\end{document}附近未知的等待点原子核的 β衰变半衰期，如124Mo, 126Ru, 128Pd, 186Nd, 188Sm, 192Dy, 194Er, 196Yb, 198Hf等，预测结果与之前的模型相近。这些结果对未来满壳层附近的r-过程物理研究有参考价值。

2021, 38(4): 368-372. doi: 10.11804/NuclPhysRev.38.2021059

2021, 38(4): 373-379. doi: 10.11804/NuclPhysRev.38.2021074

We study the so-called magic mixing angles for doubly heavy baryons. Defining that a magic mixing angle rotates states with definite \begin{document}$^{2S+1}(l_\lambda)_J$\end{document} to make them heavy-quark symmetric states, we derive the magic mixing angle only in the case \begin{document}$L_\rho=0$\end{document} between the heavy quark symmetric states with quantum numbers \begin{document}$\left(J, j_\ell\right)$\end{document} and the states with \begin{document}$\left(J, s_{\rm q}+j_\rho\right)=\left(J, \{^4l_\lambda/^2l_\lambda\}\right)$\end{document} for a doubly heavy baryon in the standard \begin{document}$\rho-\lambda$\end{document} configuration, where \begin{document}${\boldsymbol{j}}_\ell={\boldsymbol{l}}_\lambda+{\boldsymbol{s}}_{\rm q}$\end{document}, \begin{document}${\boldsymbol{s}}_\rho={\boldsymbol{s}}_{\rm Q1}+{\boldsymbol{s}}_{\rm Q2}$\end{document}, and \begin{document}${\boldsymbol{j}}_\rho={\boldsymbol{s}}_\rho+{\boldsymbol{L}}_\rho$\end{document}. We point out that when we calculate decays of doubly heavy baryons, we need to consider decays of magically mixed states, such as \begin{document}$(1S1p)1/2^-$\end{document}, \begin{document}$(1S1p)3/2^-$\end{document} and so on.

2021, 38(4): 380-388. doi: 10.11804/NuclPhysRev.38.38.2021079

2021, 38(4): 389-395. doi: 10.11804/NuclPhysRev.38.2021034

2021, 38(4): 396-401. doi: 10.11804/NuclPhysRev.38.2021051

2021, 38(4): 402-409. doi: 10.11804/NuclPhysRev.38.2021020

2021, 38(4): 410-415. doi: 10.11804/NuclPhysRev.38.2021058

2021, 38(4): 416-422. doi: 10.11804/NuclPhysRev.38.2021021

The Cooler-Storage-Ring External-target Experiment(CEE) is a spectrometer to study the properties of nuclear matter at high baryon density region. The CEE time projection chamber, which uses the state-of-the-art SAMPA electronics read-out chips is the key sub-detector of CEE. Neighboring signals in the same pad row are first grouped together to form a 2-dimensional cluster. Then a hit is created for each cluster at the ADC weighted average signal position. A cluster may also be divided into two or more hits, when the signal ADC vs. time bin has a peak-valley-peak structure, in order to obtain better two-track separation ability. The performance of the algorithm, including 0.100/0.043 cm of hit resolution and 1.1/2.8 cm of double-track resolution in the \begin{document}$x/y$\end{document} direction, is also presented.

2021, 38(4): 423-429. doi: 10.11804/NuclPhysRev.38.2021014

2021, 38(4): 430-437. doi: 10.11804/NuclPhysRev.38.2021018

A remote control system of data acquisition for the Schottky resonator at Experimental Cooler Storage Ring(CSRe) in Lanzhou has been assembled as a part of the experimental platform for nuclear mass and lifetime measurements. It is the combination of a data acquisition program and a data monitor program, both of which are exhibited in graphical user interface(GUI). It provides a number of key features to assist the users for adjusting the acquisition settings according to the experimental requirements. It is also characterized by the full utilization of a spectrum analyzer and an IQ recorder. The automatic acquisition of data files in both large size and large amount can be realized with the supplementation of an independent trigger system and a remote button pusher to overcome the intrinsic defect of the IQ recorder. It fulfills the requirements by the nuclear mass and lifetime measurements as well as other beam experiments using the Schottky resonator as the main detector at the CSRe.

2021, 38(4): 438-443. doi: 10.11804/NuclPhysRev.38.2021016

2021, 38(4): 444-451. doi: 10.11804/NuclPhysRev.38.2021031

2021, 38(4): 452-457. doi: 10.11804/NuclPhysRev.38.2021024

2021, 38(4): 458-469. doi: 10.11804/NuclPhysRev.38.2021026

2021, 38(4): 470-478. doi: 10.11804/NuclPhysRev.38.2021004

2021, 38(4): 479-486. doi: 10.11804/NuclPhysRev.38.2021043