空间环境中存在大量的高能粒子,单个高能粒子穿过航天器壳体轰击到电子器件,引发器件逻辑状态翻转、功能异常等单粒子效应,进而影响航天器的可靠运行和任务达成.基于地面加速器辐照试验模拟空间单粒子效应是评估电子器件在空间应用时发生单粒子错误风险的重要手段,只有其抗单粒子效应的指标符合宇航应用要求的器件才能在航天器中使用.航天器面临的空间辐射粒子主要是重离子和质子,它们诱发的单粒子效应也最为显著.开展宇航器件单粒子效应地面模拟试验主要依托重离子加速器和质子加速器,为满足单粒子试验需求,需要研发大面积束流扩束及均匀化、高精度束流快速诊断等技术,以及满足大批量试验任务需求的高效试验终端,重点介绍中国原子能科学研究院的基于加速器的重离子单粒子效应模拟试验技术、质子单粒子效应模拟试验技术和用于器件辐射损伤敏感区识别的重离子微束技术,以及上述技术在宇航器件单粒子效应风险评估中的应用.

In this paper, the effects of different factors, including the heavy ions striking location, incident angle, linear energy transfer (LET) value, projected range, ambient temperature and bias state, on the single event transient introduced by heavy ions irradiation in the SiGe heterojunction bipolar transistor (HBT) were investigated by the TCAD simulation. The results show that the current transient peak value, collected charge and carrier type of each terminal are changed by the striking location, incident angle and bias state. The current transient peak value and collected charge increase with the LET value, while they decrease with the ambient temperature. When heavy ions vertically irradiate the collector and substrate, the current transient peak value and collected charge increase with the projected range; therefore, the species of heavy ions should be considered in studying the single event effects of the SiGe HBT induced by heavy ions irradiation. The microphysical mechanism of these factors influencing the single event effects of the SiGe HBT is discussed in this work.

As a key technology to study the physical mechanism of single event effects (SEEs) and to identify the sensitive area of microelectronic devices, heavy ion micro-beam irradiation has been paid more and more attention by researchers. Single ion hit (SIH) is an important part of heavy ion micro-beam irradiation, which could reduce the number of incident ions to just one through a series of monitoring and control methods. Owing to this background, the single ion hit (SIH) system was established based on the pinhole heavy ion micro-beam facility in Beijing HI-13 tandem accelerator. To realize single ion hit, it is necessary to cut off the beam current immediately after monitoring the first ion incidence, so as to avoid the next ion passing through the beam switch. Therefore, the beam monitoring device is important to SIH system. The beam monitoring device consists of a 7 nm carbon film, a secondary electron detector and a beam monitoring computer. There is a fixed coefficient K between the number of ions incident on the device and the number of secondary electrons collected by the secondary electron detector. According to the value of K, the number of incident ions can be controlled by the number of secondary electrons. Through the analysis of the potential factors affecting the SIH performance, the theoretical reference formula of factors that affect the accuracy of SIH was given. The three main factors, K, beam intensity and shutter time were experimentally. The results show that the accuracy of this SIH system can reach 90% when the shutter time is 60 ms and the beam intensity is low. At the same time, lower beam intensity and shorter shutter tim are conducive to continuously improving the SIH performance. However, due to the technology limitation of the accelerator, the intensity and uniformity of the beam cannot be achieved at the same time. If the current intensity is too low, the uniformity will become much worse. Therefore, the single ion hit experiment should be carried out when the beam is relatively uniform and the K is stable. At last, the SIH system was applied to 28 nm SRAM device irradiation to reduce the interference of multiple ion incidence. Different patterns and the distribution of multiple cell upsets (MCUs) induced by the single ion were obtained, which verified the availability of the system in the research of radiation effect mechanism of nano devices. Based on the SIH system, it can be determined that all the MCUs are real events without obtaining chip layout information or post processing of data, which could improve data analysis efficiency and provide more real-time information for the experimental personnel.

The β-delayed γ decay properties of proton-rich nucleus 29S were studied with three double-sided silicon strip de-tectors surrounded by five high-purity germanium detectors on the HIRFL-RIBLL1 facility.The most precise half-life of 29S was obtained to be 183(4)ms in this experiment.The measurements of β-delayed y rays of 29S were achieved for the first time and four β-γ rays were observed accurately.The β-decay branching ratio for the low-lying excited states of 29P was de-termined and a partial decay scheme of 29S was established.Based on experimental data,the isospin symmetry breaking in the mirror decay process of the 29S→29P/29Al→29Si was studied.

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

建立了可用于器件单粒子效应(single event effect,SEE)敏感区定位的离子诱导光子发射显微镜(ion photon emission microscopy,IPEM)实验方法,利用光子产生、传输和探测装置,设计搭建了 IPEM光学成像系统,测试了适用于该系统的多种闪烁体材料的发射光谱和衰减时间等光学性质,分析对比了 160 MeV的Cl离子束辐照不同种类和不同厚度的闪烁体材料时的IPEM系统空间分辨率.研究结果表明,选用10 μm厚的ZnS(Ag)粉末作为闪烁体材料时,IPEM光学成像系统空间分辨率最佳为2.8 μm;同时,降低闪烁体材料的厚度可提高系统的空间分辨率.

As an important spaceborne electronic device, the static random access memory (SRAM) device is inevitably affected by the radiation of high-energy particles in space during its space mission. To reveal the single event effect (SEE) mechanism of 28 nm technology SRAM caused by high-energy particles, the sensitive area positioning of single event upsets (SEUs) and the distribution characteristics of multi-cell upsets (MCUs) were studied based on the pinhole heavy ion micro-beam facility. The results show that the actual range of SEUs caused by micro-beam irradiation is 4.8 μm × 7.8 μm. By moving the device platform in small steps (1 μm each step), a one-dimensional positioning method for locating the sensitive area of SEUs was established, which can reduce the dependence of localization accuracy on beam spot size, and the positioning accuracy can be improved to 1 μm. The MCU test indicates that the upset pattern is closely related to the spacing of sensitive areas within adjacent SRAM cells, and the probability of MCUs is reduced by well contacts and bit interleaving.

The study of the origin of asymmetries in mirror β decay is extremely important to understand the fundamental nuclear force and the nuclear structure. The experiment was performed at the National Laboratory of Heavy Ion Research Facility in Lanzhou (HIRFL) to measure the β-delayed γ rays of 26P by silicon array and Clover-type high-purity Germanium (HPGe) detectors. Combining with results from the β decay of 26P and its mirror nucleus 26Na, the mirror asymmetry parameter δ ( ≡ft+/ft−− 1) was determined to be 46(13)% for the transition feeding the first excited state in the daughter nucleus. Our independent results support the conclusion that the large mirror asymmetry is close to the proton halo structure in 26P.

在兰州重离子研究装置上，依托兰州放射性束流线，产生、分离和鉴别了同位旋第三分量 \begin{document}$ T_{Z}=-2 $\end{document} 的近质子滴线核28S，并通过使用包括双面硅条探测器和高纯锗探测器在内的探测阵列，开展了28S的 \begin{document}$\beta$\end{document} 延迟 \begin{document}$\gamma$\end{document} 衰变测量。实验准确测量了28S衰变中的5条 \begin{document}$\beta$\end{document} 延迟 \begin{document}$\gamma$\end{document} 射线，得到了子核28P相应能级的能量。首次提取出了 \begin{document}$\beta$\end{document} 衰变布居到28P低激发态的衰变分支比，并构筑了28S的全新部分衰变纲图。本工作为将来进一步比较28S和28Mg间的镜像不对称性提供了精确的实验数据。

在兰州重离子研究装置上,依托兰州放射性束流线,产生、分离和鉴别了同位旋第三分量TZ=?2的近质子滴线核28 S,并通过使用包括双面硅条探测器和高纯锗探测器在内的探测阵列,开展了28 S的β延迟γ衰变测量.实验准确测量了28 S衰变中的5条β延迟γ射线,得到了子核28 P相应能级的能量.首次提取出了β衰变布居到28P低激发态的衰变分支比,并构筑了28S的全新部分衰变纲图.本工作为将来进一步比较28S和28Mg间的镜像不对称性提供了精确的实验数据.

为研究束流漂移对结构紧凑 、覆盖立体角较大的硅条探测器阵列测量的影响,利用蒙特卡罗方法,模拟了不同方向 、不同大小的束流漂移对熔合蒸发残余核 α 衰变和卢瑟福散射角分布的影响,表明束流漂移距离小于3.0 mm时,探测器阵列的对称性能将计数误差控制在10％ 以下.开展了25 MeV和40 MeV 6 Li+209 Bi体系的实验测量,利用监视器数据研究了束流漂移的情况,结果表明,所有轮次的束流漂移均未超过3.0 mm.对束流漂移进行修正后,用3种不同的立体角刻度方法得到了弹性散射角分布,感兴趣的40 MeV数据与文献数据基本一致.

由于受到放射性束强度弱、品质差的限制,奇特核体系的光学势性质一直是亟待解决的国际难题.本工作利用稳定束的转移反应作为探针,深入研究了反应出射道奇特核体系的光学势性质.利用中国原子能科学研究院的HI-13串列加速器在近库仑位垒能区高精度测量了7Li+ 63Cu、208 Pb的弹性散射以及单质子转移反应角分布,并利用扭曲波玻恩近似(DWBA)和耦合反应道(CRC)方法对实验数据进行了拟合,抽取了出射道6 He+64Zn、209Bi晕核体系的光学势参数.所得参数可重现文献中已有的6He体系的弹性散射角分布,验证了这种方法的可靠性.对所得势参数的能量相依性的分析表明,在重体系6 He+209 Bi中,基于因果律的色散关系并不适用,其潜在的物理原因还需进一步深入研究.

利用背角准弹散射的方法开展了近库仑势垒(近垒)能区重离子核反应机制的研究.高精度测量了深垒下能区16 O+152,154 Sm、184W、196 Pt和208Pb等体系的背角准弹散射激发函数,用耦合道计算抽取了核势的表面弥散参数,结果表明考虑耦合道效应得到的表面弥散参数值正常.基于背角准弹散射势垒分布对核结构的敏感性,尝试用深垒下能区10O+152 Sm、170 Er和174 Yb等体系的背角准弹散射来抽取形变靶核的十六极形变参数,所抽取值与已有结果趋势一致,说明了该方法的可行性.此外,研究了弱束缚核体系的破裂效应,其表现为背角准弹势垒分布较全熔合势垒分布向低能移动,所得结果进一步说明势垒分布同时含有核结构和核反应机制的信息.