标题： 富勒烯原子笼内原子的巨大共振的破坏与复活 A@C60 显示英文标题

标题： Destruction and Resurrection of Atomic Giant resonances in Endohedral Atoms A@C60

摘要： 实验证明，在内嵌原子的光吸收过程中，由于富勒烯壳层的不同作用，一些原子巨共振几乎完全被破坏，而另一些则完全得以保留。作为第一个例子，我们讨论了Xe@C60中的4d10巨共振；而第二个例子则是Eu@C60中的巨自电离共振。这种定性差异源于4d巨共振的光电子能量较小（几十电子伏特），并且会被C60富勒烯壳层强烈反射。至于Eu@C60，巨自电离会产生高能光电子（约数百电子伏特），这些光电子几乎不受C60壳层的影响。由于出射电子能量的不同，A@C60中的原子巨共振将被大量破坏，而巨自电离共振则几乎完全保留。因此，从Xe@C60巨共振到Eu@C60巨自电离共振的过程中，振荡结构应该会消失。类似地，对于角度各向异性参数而言，在纯巨共振到纯巨自电离共振的过渡过程中，振荡也会减少。在巨共振频率下，入射光束对富勒烯壳层的极化作用可以忽略不计。而对于Eu@C60的外层电子的光电离现象，情况则完全不同，这也将被进一步考虑。 显示英文摘要

摘要： It is demonstrated that in photoabsorption by endohedral atoms some atomic Giant resonances are almost completely destroyed while the others are totally preserved due to different action on it of the fullerenes shell. As the first example we discuss the 4d10 Giant resonance in Xe@C60 whereas as the second serves the Giant autoionization resonance in Eu@C60. The qualitative difference comes from the fact that photoelectrons from the 4d Giant resonance has small energies (tens of eV) and are strongly reflected by the C60 fullerenes shell. As to the Eu@C60, Giant autoionization leads to fast photoelectrons (about hundred eV) that go out almost untouched by the C60 shell. As a result of the outgoing electrons energy difference the atomic Giant resonances will be largely destroyed in A@C60 while the Giant autoionization resonance will be almost completely preserved. Thus, on the way from Xe@C60 Giant resonance to Eu@C60 Giant autoionization resonance the oscillation structure should disappear. Similar will be the decrease of oscillations on the way from pure Giant to pure Giant autoionization resonances for the angular anisotropy parameters. At Giant resonance frequencies the role of polarization of the fullerenes shell by the incoming photon beam is inessential. Quite different is the situation for the outer electrons in Eu@C60, the photoionization of which will be also considered.