Article title: First proof-of-principle experiment with the post-accelerated isotope separator on-line beam at BRIF: Measurement of the angular distribution of ²³Na + ⁴⁰Ca elastic scattering

BRIF后加速ISOL束流的首次原理验证实验：²³Na + ⁴⁰Ca弹性散射角分布的测量

DOI: 10.1007/s41365-021-00889-9

One sentence summary:

Exotic properties of unstable nuclei can be investigated using the post-accelerated isotope separator on-line beam at BRIF.

一句话摘要：利用BRIF后加速的ISOL束流可以研究不稳定的奇异原子核性质。

http://www.nst.sinap.ac.cn/newsDetails/112/3765/en/

The Novelty (What)

Is it feasible to perform measurements of properties of unstable exotic nuclei at BRIF using the isotope separator on-line (ISOL) technique? This study confirmed the feasibility by performing the first-ever high-precision proof-of-principle experiment with a high-quality post-accelerated ²³Na beam (using the ISOL technique) at BRIF. Such was primarily made possible by measuring the angular distribution of ²³Na + ⁴⁰Ca elastic scattering. The angular distribution measured showed consistency with the high-precision Q3D magnetic spectrograph measurements (using non-ISOL beam). Thus, this breakthrough enables researchers to explore the properties of unstable nuclei by using the isotope separator on-line (ISOL) technique.

创新性（主要内容）：在BRIF上使用在线同位素分离(ISOL)技术测量不稳定的奇异原子核性质是否可行？ 本研究利用后加速的高品质²³Na束流（使用ISOL技术）在BRIF首次进行了高精度的原理验证实验，证实了该技术的可行性。 这主要是通过测量²³Na + ⁴⁰Ca的弹性散射角分布来实现的。 测得的角分布与高分辨Q3D磁谱仪（使用非ISOL束流）的测量结果一致。 由此可见，这一突破使研究人员能够通过在线同位素分离技术（BRIF）来探索不稳定核素的性质。

The Background (Why)

A nuclear drip line is a boundary delimiting the zone beyond which atomic nuclei decay by the emission of a proton or neutron. Nuclei with short life, unstable, radioactive are known to be exotic when they develop unusual structures. Meanwhile, the reaction dynamics of light exotic nuclei near the drip line have been getting significant attention, especially from the low-energy nuclear physics community. Several important properties of exotic nuclei include the size and surface diffusiveness which can be determined using elastic scattering. Such measurements were commonly performed at accelerators using the projectile fragmentation technique. However, reported studies that applied the ISOL technique for the same purpose were rare. By presenting the above-mentioned proof-of-principle experiment conducted at the Beijing Radioactive Ion Beam Facility (BRIF), the potential and feasibility of the technique were proven in this study. Furthermore, the output of this research gave validation for scientists to apply the ISOL technique in relevant investigations of the reaction dynamics of exotic nuclei.

研究背景（主要内容）：原子核滴线是指原子核因发射质子或中子而衰变的区域的边界。 寿命短、不稳定、有放射性的原子核，当它们发展出不寻常的结构时，就被认为是奇异的。 同时，轻奇异核在滴线附近的反应动力学也受到了特别是低能核物理界的关注。 奇异核的几个重要性质包括核的尺寸和表面扩散，它们可以用弹性散射来确定。 这类测量通常是在加速器上使用弹核碎裂技术进行的。 然而，为同一目的应用ISOL技术的研究报道很少。 通过在北京放射性核束装置(BRIF)进行的上述原理验证实验，验证了该技术的潜力和可行性。 此外，本研究成果为科学家们将ISOL技术应用于奇异核反应动力学的相关研究提供了依据。

The SDG impact (Big Why)

The properties of unstable exotic nuclei can become very different from those of stable isotopes. That implies the existence of unexplored applications of exotic nuclei in nuclear technology. By introducing a highly reliable technique for the characterization of nuclei, this study established a strong foundation for future studies of exotic nuclei. Hence, it contributes to the realization of UNSDG 9: Industries, Innovation & Infrastructure by supporting future research related to nuclear science.

SDG影响力（研究意义）不稳定奇异核的性质与其对应稳定同位素的性质可能有很大不同。 这意味着在核技术中存在着未经探索的奇异核的应用。 通过引入一种高度可靠的原子核表征技术，这项研究为今后研究奇异原子核奠定了坚实的基础。 因此，它通过支持与核科学有关的未来研究，为实现联合国可持续发展目标9：工业、创新和基础设施作出了贡献。