We present the first measurements of photoelectron spectra of atomic clusters embedded in superfluid helium (He) nanodroplets. Owing to the large absorption cross section of xenon (Xe) around 100 eV photon energy (4d inner-shell ionization), direct dopant photoionization exceeds charge transfer ionization via the ionized He droplets. Despite the predominant creation of Xe 2+ and Xe 3+ by subsequent Auger decay of free Xe atoms, for Xe embedded in He droplets only singly charged ##IMG## [http://ej.iop.org/images/0953-4075/53/20/204001/babaafbieqn1.gif] {${\mathrm{X}\mathrm{e}}_{k}^{+}$} , k = 1, 2, 3 fragments are observed. Broad Xe + ion kinetic-energy distributions indicate Coulomb explosion of the ions due to electron transfer to the primary Auger ions from surrounding neutral atoms. The electron spectra correlated with Xe ions emitted from the He nanodroplets contain a low-energy feature and nearly unshifted Xe photoli...

中文翻译：

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嵌入氦纳米液滴中的Xe原子的直接内壳光电离

我们介绍了嵌入超流氦（He）纳米液滴中的原子团簇的光电子能谱的首次测量。由于氙气（Xe）的吸收截面大，大约100 eV光子能量（4d内壳电离），直接掺杂剂电离超过通过电离的He液滴进行的电荷转移电离。尽管随后通过自由Xe原子的俄歇衰变而主要产生Xe 2+和Xe 3+，但对于嵌入He液滴中的Xe而言，它仅是单电荷的## IMG ## [http://ej.iop.org/images/0953- 4075/53/20/204001 / babaafbieqn1.gif] {$ {\ mathrm {X} \ mathrm {e}} _ {k} ^ {+} $}，观察到k = 1，2，3个片段。宽泛的Xe +离子动能分布表明，由于电子从周围的中性原子转移到初级俄歇离子上，因此离子发生了库仑爆炸。