Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), 28040 Madrid, Spain.
I. Physics Institute and JARA-FAME, RWTH Aachen University, 52056 Aachen, Germany.
Phys Rev Lett. 2023 May 26;130(21):211002. doi: 10.1103/PhysRevLett.130.211002.
We report the properties of primary cosmic-ray sulfur (S) in the rigidity range 2.15 GV to 3.0 TV based on 0.38×10^{6} sulfur nuclei collected by the Alpha Magnetic Spectrometer experiment (AMS). We observed that above 90 GV the rigidity dependence of the S flux is identical to the rigidity dependence of Ne-Mg-Si fluxes, which is different from the rigidity dependence of the He-C-O-Fe fluxes. We found that, similar to N, Na, and Al cosmic rays, over the entire rigidity range, the traditional primary cosmic rays S, Ne, Mg, and C all have sizeable secondary components, and the S, Ne, and Mg fluxes are well described by the weighted sum of the primary silicon flux and the secondary fluorine flux, and the C flux is well described by the weighted sum of the primary oxygen flux and the secondary boron flux. The primary and secondary contributions of the traditional primary cosmic-ray fluxes of C, Ne, Mg, and S (even Z elements) are distinctly different from the primary and secondary contributions of the N, Na, and Al (odd Z elements) fluxes. The abundance ratio at the source for S/Si is 0.167±0.006, for Ne/Si is 0.833±0.025, for Mg/Si is 0.994±0.029, and for C/O is 0.836±0.025. These values are determined independent of cosmic-ray propagation.
我们基于阿尔法磁谱仪实验（AMS）收集的 0.38×10^{6}个硫原子核，报告了 2.15 GV 至 3.0 TV 能区原始宇宙射线硫（S）的性质。我们观察到，在 90 GV 以上，S 通量的刚性依赖性与 Ne-Mg-Si 通量的刚性依赖性相同，这与 He-C-O-Fe 通量的刚性依赖性不同。我们发现，类似于 N、Na 和 Al 宇宙射线，在整个刚性范围内，传统的原始宇宙射线 S、Ne、Mg 和 C 都具有相当大的二次成分，并且 S、Ne 和 Mg 通量很好地由原始硅通量和二次氟通量的加权和描述，而 C 通量很好地由原始氧通量和二次硼通量的加权和描述。传统原始宇宙射线通量 C、Ne、Mg 和 S（甚至 Z 元素）的初级和次级贡献与 N、Na 和 Al（奇数 Z 元素）通量的初级和次级贡献明显不同。在源处 S/Si 的丰度比为 0.167±0.006，Ne/Si 的丰度比为 0.833±0.025，Mg/Si 的丰度比为 0.994±0.029，C/O 的丰度比为 0.836±0.025。这些值是独立于宇宙射线传播确定的。
