Okumura T, Azuma T, Bennett D A, Caradonna P, Chiu I, Doriese W B, Durkin M S, Fowler J W, Gard J D, Hashimoto T, Hayakawa R, Hilton G C, Ichinohe Y, Indelicato P, Isobe T, Kanda S, Kato D, Katsuragawa M, Kawamura N, Kino Y, Kubo M K, Mine K, Miyake Y, Morgan K M, Ninomiya K, Noda H, O'Neil G C, Okada S, Okutsu K, Osawa T, Paul N, Reintsema C D, Schmidt D R, Shimomura K, Strasser P, Suda H, Swetz D S, Takahashi T, Takeda S, Takeshita S, Tampo M, Tatsuno H, Tong X M, Ueno Y, Ullom J N, Watanabe S, Yamada S
Atomic, Molecular and Optical Physics Laboratory, RIKEN, Wako 351-0198, Japan.
National Institute of Standards and Technology, Boulder, Colorado 80305, USA.
Phys Rev Lett. 2021 Jul 30;127(5):053001. doi: 10.1103/PhysRevLett.127.053001.
We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kβ x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.
我们使用超导转变边缘传感器微热量计观测了μ子化铁原子发射的电子K x射线。半高宽为5.2 eV的能量分辨率使我们能够观测到电子特征Kα和Kβ x射线的不对称宽谱，以及6 keV附近的超卫星K^{h}α x射线。这种特征反映了负μ子和L壳层电子对核电荷的时间相关屏蔽，并伴有电子侧向馈入。在模拟的辅助下，这些数据清楚地揭示了在μ子级联过程中10 - 20 fs尺度上电子K壳层和L壳层空穴的产生及其时间演化。
