Study of multiple photoionization processes by multi-electron coincidence spectroscopy

多电子符合光谱研究多重光电离过程

• 批准号: 18540399
• 负责人: ITO Kenji
• 金额: $ 2.34万
• 依托单位: High Energy Accelerator Research Organization
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18540399/
• 关键词: photoionization; multiple ionization; coincidence; time-of-flight; vacuum ultra violet; soft x-ray; 光電離過程; 多重電離過程; 真空紫外・軟X線

We have carried out multi-electron coincidence spectroscopy for investigating multiple photoionization processes of atoms and molecules. For this aim, it is very important to have a magnetic bottle time-of-flight electron spectrometer with high detection efficiency, and pulsed time structure of synchrotron radiation. For Ne atoms, we have obtained the final state-selective double photoionization cross sections for the incident photon energy region from the thresholds to 200eV, where the two electrons are ionized from the 2s and 2p outer shells. This is the first precise experimental data supplying an opportunity of rigorous examination for existing theories. In Xe atoms, the abnormal behavior of 4p photoelectron peaks has been paid attention since its first observation by Swedish group in 1976 ; the 4p_<1/2>peak is completely smeared out and the 4p_<3/2>peak is appeared as a complex structure. We have found an abnormal enhancement of 4d^2 double ionization, and analyzed precisely the e … More nergy correlation between these two electrons, which reveals that the Xe^<2+> 4d^<-2> states are produced via Super-Coster-Kronig processes of Xe+ 4p-1 states, which was predicted theoretically 30 years ago, and now proved experimentally with a new powerful coincidence spectOscopy. Furthermore, we have studied double photoionization of CO molecules, where an outer shell electron is simultaneously emitted with inner shell ionization of a C1s or O1ss electron. With coincidence measurements of these two electrons, we have found on the spectral features that the properties of the CO^<2+> states are characterized by the interaction between the localized valence holes and the core holes.These results have been reported in the academic journals and presented at the internal and international conferences as shown in the next pages. While so far we have been interested in double photoionization processes where two electrons makes important roles, we will develop our study three electrons processes, using a mechanical light chopper accomplished with an aid of this grant. Actually, we have already obtained interesting results on Ar triple ionization, which will be submitted to a journal very soon. Less

我们开展多电子符合光谱研究原子和分子的多重光电离过程，为此，拥有高探测效率的磁瓶飞行时间电子能谱仪和同步加速器的脉冲时间结构非常重要。对于 Ne 原子，我们获得了从阈值到 200eV 的入射光子能量区域的最终状态选择性双光电离截面，其中两个电子从 2s 开始电离。这是第一个精确的实验数据，为现有理论提供了严格检验的机会，自 1976 年瑞典团队首次观察到 4p_< 以来，4p 光电子峰的异常行为就受到了关注。 1/2>峰完全被抹掉，4p_<3/2>峰呈现为复杂结构。我们发现了4d^2双电离的异常增强，并进行了分析。正是这两个电子之间的 e … More 能量相关性，揭示了 Xe^<2+> 4d^<-2> 态是通过 Xe+ 4p-1 态的 Super-Coster-Kronig 过程产生的，这在理论上是被预测的 30几年前，现在用一种新的强大的重合光谱实验证明了这一点。此外，我们还研究了CO分子的双光电离，其中外层电子与内层电离同时发射。通过对这两个电子的重合测量，我们发现CO^<2+>态的性质是由局域价空穴与核心空穴之间的相互作用来表征的。如下页所示，虽然到目前为止我们一直对两个电子发挥重要作用的双光电离过程感兴趣，但我们将使用三电子过程来发展我们的研究。机械灯实际上，我们已经在 Ar 三电离方面取得了有趣的结果，很快就会提交给期刊。

项目成果

Autoionization of Ne^+^ Rydberg states formed through valence photoemission

通过价态光电子发射形成 Ne^ ^ Rydberg 态的自电离

• 发表时间: 2007
• 期刊: J. Phys. B40
• 作者: T. Kaneyasu;Y. Hikosaka;E. Shigemasa;F. Penent;P. Lablanquie;T. Aoto;K. Ito
• 通讯作者: K. Ito

Autoionization of Ne^+ Rydberg states formed via valence photoemission

通过价光电子发射形成 Ne^ Rydberg 态的自电离

• 发表时间: 2007
• 期刊: Journal of Physics B 40
• 作者: T. Kaneyasu;Y. Hikosaka;E. Shigemasa;F. Penent;P. Lablanquie;T. Aoto and K. Ito
• 通讯作者: T. Aoto and K. Ito

Multiple ionization of atoms with multi coincidence spectroscopy

用多重符合光谱进行原子的多重电离

• 发表时间: 2008
• 作者: Hikosaka;Kaneyasu;Shigemasa;Lablanquie;Penent;Eland;Ito
• 通讯作者: Ito

State-selective cross sections of multiple photoionization in Ne

• DOI: 10.1103/physreva.76.012717
• 发表时间: 2007-07
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: T. Kaneyasu;Y. Hikosaka;E. Shigemasa;F. Penent;P. Lablanquie;T. Aoto;K. Ito

磁気ボトル型電子エネルギー分析器によるNe光二重イオン化部分断面積の測定

利用磁瓶式电子能量分析仪测量氖光双电离部分截面

• 发表时间: 2007
• 作者: 金安達夫,彦坂泰正,繁政英治,F. Penent;P. Lablanquie,青戸智浩,伊藤健二
• 通讯作者: P. Lablanquie,青戸智浩,伊藤健二