由美国密歇根州立大学稀有同位素束设施(FRIB)领导的国际研究团队成功揭示了锌-70核素释放的低能伽马射线的来源，将其追溯到核内的磁转变[1]。这一发现刊登在《自然》杂志上，题为《Magnetic Character of the Low-Energy Enhancement in 70Zn》[1]，有助于改进关于恒星、超新星和中子星并合如何制造重元素的科学模型[1]。
低能增强现象已困扰科学界数十年[1]。研究发现，磁转变产生了这种低能增强现象，进而增加中子捕获反应的频率[1]。这一机制在超新星和中子星并合等极端宇宙事件中扮演关键角色，直接影响宇宙中重元素的产生过程[1]。此项国际合作汇聚了来自美国、加拿大、意大利、德国、挪威和韩国共25个机构的科研力量[1]，研究团队运用了FRIB的低能束和离子阱(LEBIT)以及求和NaI(SuN)探测器等专门仪器完成了这项研究[1]。
An international research team led by the Facility for Rare Isotope Beams (FRIB) at Michigan State University has identified the source of mysterious low-energy gamma rays emitted by zinc-70 nuclei, tracing the phenomenon to a magnetic transition within the nucleus.[1] The discovery, published in Nature under the title "Magnetic Character of the Low-Energy Enhancement in 70Zn," advances scientific understanding of how heavy elements are created in stars, supernovae, and neutron star mergers.[1]
The research resolves a puzzle that has confronted the scientific community for decades: the origin of the low-energy enhancement (LEE) phenomenon observed in certain nuclei.[1] The team determined that magnetic transitions produce this effect, which increases the frequency of neutron capture reactions.[1] This enhanced neutron capture directly influences heavy element production during extreme cosmic events such as supernovae and neutron star mergers, making the findings crucial for refining models of stellar nucleosynthesis.[1]
The collaboration involved 25 institutions from the United States, Canada, Italy, Germany, Norway, and South Korea.[1] Researchers employed specialized instruments at FRIB, including the Low-Energy Beam and Ion Trap (LEBIT) and the Summing NaI (SuN) detector, to conduct the investigation.[1]