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8. List of participants

Author

Abe, M., primary, Abo, M., additional, Abukawa, T., additional, Adachi, J., additional, Agui, A., additional, Aita, O., additional, Aiura, Y., additional, Ajello, J., additional, Akaki, O., additional, Akazawa, H., additional, Aksela, H., additional, Aksela, S., additional, Allen, J., additional, Altun, Z., additional, Amemiya, K., additional, Amusia, M., additional, An, K., additional, Andersen, J., additional, Aoki, S., additional, Arakawa, I., additional, Araki, T., additional, Arp, U., additional, Asensio, M., additional, Awaya, Y., additional, Awazu, K., additional, Azuma, H., additional, Azuma, Y., additional, Baba, Y., additional, Bando, H., additional, Bao, Z., additional, Becker, U., additional, Bengtsson, P., additional, Bobashev, S., additional, Bocquet, A., additional, Breton, J., additional, Cai, Y., additional, Caldwell, C., additional, Cauletti, C., additional, Chainani, A., additional, Che, J., additional, Chen, C., additional, Chen, L., additional, Chen, X., additional, Cherepkov, N., additional, Cho, T., additional, Christou, C., additional, Chung, J., additional, Couprie, M., additional, Cramer, S., additional, Da Silva, L., additional, Daimon, H., additional, Deguchi, K., additional, Dessau, D., additional, Dhanak, V., additional, Dolmatov, V., additional, Drube, W., additional, Echigo, S., additional, Ehresmann, A., additional, Eisebitt, S., additional, Ejima, T., additional, Ejiri, A., additional, Endo, O., additional, England, J., additional, Enta, Y., additional, Fadley, C., additional, Feldhaus, J., additional, Filatova, E., additional, Finazzi, M., additional, Finkenthal, M., additional, Fischer, D., additional, Flechsig, U., additional, Franzén, K., additional, Frasinski, L., additional, Fujikawa, T., additional, Fujimori, A., additional, Fujimori, S., additional, Fujisawa, M., additional, Fujita, K., additional, Fujita, M., additional, Fukui, K., additional, Fukutani, H., additional, Ghijsen, J., additional, Gluskin, E., additional, Guo, Q., additional, Guyon, P., additional, Hague, C., additional, Hall, R., additional, Hamamatsu, H., additional, Han, Z., additional, Hansen, J., additional, Hanyu, T., additional, Happo, N., additional, Hara, T., additional, Harada, I., additional, Harada, Y., additional, Hasegawa, M., additional, Hasegawa, S., additional, Hatano, T., additional, Hatherly, P., additional, Hattori, T., additional, Hayaishi, T., additional, Hayasi, T., additional, Heck, C., additional, Heinzmann, U., additional, Hieda, K., additional, Higashiyama, K., additional, Hirai, Y., additional, Hiraya, A., additional, Hirayama, T., additional, Hirose, S., additional, Hishikawa, A., additional, Hopkirk, A., additional, Horikawa, Y., additional, Hosaka, N., additional, Huber, K., additional, Huff, W., additional, Hussain, Z., additional, Hwang, C., additional, Ibrahim, K., additional, Ibuki, T., additional, Ichikawa, K., additional, Ichikawa, M., additional, Igarashi, J., additional, Iguchi, Y., additional, Iimura, K., additional, Iinuma, D., additional, Iketaki, Y., additional, Ikeura, H., additional, Imada, S., additional, Imaizumi, Y., additional, Imanishi, A., additional, Inokuchi, H., additional, Inoue, I., additional, Ishigame, M., additional, Ishiguro, E., additional, Ishii, H., additional, Ishii, T., additional, Ishijima, H., additional, Ishizue, I., additional, Isoyama, G., additional, Ito, K., additional, Itoh, M., additional, Itoh, Y., additional, Iwami, M., additional, Iwano, K., additional, Iwasaki, K., additional, Iwata, S., additional, Jacobsen, C., additional, Jikimoto, T., additional, Jo, T., additional, Johansson, L., additional, Johansson, U., additional, Jouda, K., additional, Jung, C., additional, Kabachnik, N., additional, Kaindl, G., additional, Kakizaki, A., additional, Kamada, M., additional, Kamata, A., additional, Kamenskikh, I., additional, Kameta, K., additional, Kamiya, K., additional, Kamiya, Y., additional, Kan'no, K., additional, Kanomata, T., additional, Kasaya, M., additional, Kashiwakura, T., additional, Kato, R., additional, Kato, Y., additional, Katoh, R., additional, Kaurila, T., additional, Kawai, J., additional, Kawamura, T., additional, Kayanuma, Y., additional, Kaznacheyev, K., additional, Kennedy, E., additional, Kiguchi, M., additional, Kihara, H., additional, Kimpara, Y., additional, Kimura, A., additional, Kimura, H., additional, Kimura, K., additional, Kimura, S., additional, Kinoshita, T., additional, Kirm, M., additional, Kisker, E., additional, Kitade, T., additional, Kitajima, M., additional, Kitajima, Y., additional, Kitamura, H., additional, Kitaura, M., additional, Kobayashi, K., additional, Kobayashi, M., additional, Koda, T., additional, Kohagura, J., additional, Koide, T., additional, Koike, F., additional, Koike, M., additional, Koike, T., additional, Koizumi, T., additional, Kojima, T., additional, Kondo, K., additional, Kondo, Y., additional, Kono, M., additional, Kono, S., additional, Korde, R., additional, Koseki, T., additional, Kosugi, N., additional, Kotani, A., additional, Kotani, M., additional, Kouchi, N., additional, Kowalski, M., additional, Koyama, M., additional, Koyano, I., additional, Krause, M., additional, Krupa, J., additional, Kumigashira, H., additional, Kuninobu, T., additional, Kurita, S., additional, Kusaka, M., additional, Kutluk, G., additional, Lablanquie, P., additional, Lama, F., additional, Larkins, F., additional, Latimer, C., additional, Lebrun, T., additional, Lee, D., additional, Lee, K., additional, Lee, T., additional, Legrand, F., additional, Lewis, B., additional, Li, D., additional, Lindau, I., additional, Liu, F., additional, Lodha, G., additional, Lu, E., additional, Lushchik, A., additional, Lyakhovskaya, I., additional, Mårtensson, N., additional, Ma, Y., additional, Machida, S., additional, Maeda, F., additional, Maeyama, S., additional, Maezawa, H., additional, Manakov, N., additional, Margaritondo, G., additional, Masui, S., additional, Masuoka, T., additional, Matsui, F., additional, Matsukawa, T., additional, Matsumoto, M., additional, Matsumoto, S., additional, Matsushita, T., additional, Matsuzawa, M., additional, Mattogno, G., additional, Messina, A., additional, Mikhailin, V., additional, Mimura, K., additional, Minami, T., additional, Misu, A., additional, Mitsuishi, T., additional, Mitsuke, K., additional, Mitsumoto, R., additional, Miyahara, T., additional, Miyamae, T., additional, Miyamoto, N., additional, Miyauchi, H., additional, Mizokawa, T., additional, Morgan, H., additional, Mori, I., additional, Mori, T., additional, Morin, P., additional, Morioka, Y., additional, Mosnier, J., additional, Munro, I., additional, Murakami, E., additional, Murata, T., additional, Murata, Y., additional, Muro, T., additional, Nagakura, I., additional, Nagaoka, S., additional, Nagata, T., additional, Nahon, L., additional, Nakagawa, K., additional, Nakai, I., additional, Nakai, S., additional, Nakai, Y., additional, Nakaishi, H., additional, Nakajima, N., additional, Nakamura, H., additional, Nakamura, M., additional, Nakatake, M., additional, Nakazawa, M., additional, Namatame, H., additional, Namioka, T., additional, Nanba, T., additional, Naoe, S., additional, Nasu, K., additional, Neeb, M., additional, Nenner, I., additional, Nishihara, Y., additional, Nishioka, H., additional, Niwano, M., additional, Nordgren, J., additional, Norman, D., additional, Nowak, C., additional, Nyholm, R., additional, Nylén, H., additional, Ogasawara, H., additional, Ogata, T., additional, Oh, S., additional, Ohara, J., additional, Ohashi, H., additional, Ohchi, T., additional, Ohmori, K., additional, Ohnishi, A., additional, Ohno, N., additional, Ohta, T., additional, Oji, H., additional, Okada, K., additional, Okajima, T., additional, Okane, T., additional, Okuda, T., additional, Okunishi, M., additional, Okusawa, M., additional, Olson, C., additional, Onellion, M., additional, Ono, I., additional, Ono, K., additional, Onsgaard, J., additional, Onuki, H., additional, Oshima, M., additional, Ouchi, I., additional, Ouchi, Y., additional, Oura, M., additional, Park, C., additional, Park, S., additional, Perera, R., additional, Petroff, Y., additional, Poliakoff, E., additional, Pong, W., additional, Prabhakaran, K., additional, Pratt, R., additional, Qvarford, M., additional, Rader, O., additional, Rahn, S., additional, Randall, K., additional, Reininger, R., additional, Rosenberg, R., additional, Rubensson, J., additional, Sainctavit, P., additional, Saito, N., additional, Saito, T., additional, Saitoh, T., additional, Saitoh, Y., additional, Sakamoto, K., additional, Sakano, M., additional, Sakisaka, Y., additional, Samson, J., additional, Sarma, D., additional, Sasaki, T., additional, Sasano, T., additional, Sato, H., additional, Sato, N., additional, Sato, S., additional, Sato, Y., additional, Savchenko, E., additional, Schattke, W., additional, Schlachter, F., additional, Schmidt, V., additional, Schwentner, N., additional, Seki, K., additional, Sekiguchi, T., additional, Sekitani, T., additional, Sekiyama, A., additional, Seno, H., additional, Shafi, M., additional, Sham, T., additional, Sheng, L., additional, Shi, C., additional, Shidara, T., additional, Shigemasa, E., additional, Shimada, H., additional, Shimada, K., additional, Shimamura, I., additional, Shimizu, Y., additional, Shimoyama, I., additional, Shin, S., additional, Shiraga, H., additional, Shirai, M., additional, Shishidou, T., additional, Shmaenok, L., additional, Shobatake, K., additional, Simon, M., additional, Smith, N., additional, Soda, K., additional, Solov'yov, A., additional, Sonntag, B., additional, Spanke, D., additional, Stankevitch, V., additional, Steinberger, I., additional, Steiner, P., additional, Suga, S., additional, Sugawara, H., additional, Sutherland, D., additional, Suzuki, I., additional, Suzuki, M., additional, Suzuki, N., additional, Suzuki, S., additional, Suzuki, T., additional, Taguchi, Y., additional, Takahashi, N., additional, Takahashi, T., additional, Takakuwa, Y., additional, Takata, Y., additional, Takatsuchi, K., additional, Takeichi, A., additional, Takenaka, H., additional, Takizawa, Y., additional, Tanaka, A., additional, Tanaka, K., additional, Tanaka, M., additional, Tanaka, S., additional, Tanaka, T., additional, Tang, J., additional, Tani, K., additional, Taniguchi, M., additional, Tayu, T., additional, Terada, S., additional, Terminello, L., additional, Tezuka, H., additional, Tezuka, Y., additional, Thissen, R., additional, Tinone, M., additional, Tokue, I., additional, Tonner, B., additional, Toyota, E., additional, Troussel, P., additional, Ueda, K., additional, Ueda, Y., additional, Ueno, N., additional, Uhrberg, R., additional, Ukai, M., additional, Umehara, T., additional, Uozumi, T., additional, Urisu, T., additional, Vaeterlein, P., additional, Van der Laan, G., additional, Van Hove, M., additional, Viane, P., additional, Voss, J., additional, Wang, X., additional, Watanabe, M., additional, Watanabe, N., additional, Watanabe, Y., additional, Weaver, J., additional, West, J., additional, van Wezenbeek, E., additional, Whitfield, S., additional, Woodruff, D., additional, Wu, L., additional, Wu, R., additional, Xu, P., additional, Xu, W., additional, Yagi, K., additional, Yagi, S., additional, Yagishita, A., additional, Yamada, T., additional, Yamakawa, T., additional, Yamamoto, H., additional, Yamamoto, M., additional, Yamamoto, Y., additional, Yamanaka, T., additional, Yamanouchi, K., additional, Yamashita, K., additional, Yanagihara, M., additional, Yang, S., additional, Yang, Y., additional, Yeom, H., additional, Yimagawa, M., additional, Ynzunza, R., additional, Yokoya, T., additional, Yokoyama, T., additional, Yoshida, A., additional, Yoshida, H., additional, Yoshi, K., additional, Yoshimura, D., additional, Yuri, M., additional, Zama, T., additional, Zeitoun, P., additional, Zhang, X., additional, Zhang, Y., additional, Zimmerer, G., additional, and Zimmermann, R., additional

Published
1996
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9. Breakdown of ionic character of molecular alkali bromides in inner-valence photoionization.

Author

Karpenko, A., Iablonskyi, D., Urpelainen, S., Kettunen, J. A., Cao, W., Huttula, M., and Aksela, H.

Subjects
ALKALIES, BROMIDES, PHOTOIONIZATION, IONIZATION (Atomic physics), MOLECULAR spectroscopy
Abstract

The inner-valence region of alkali bromide XBr (X=Li, Na, K, Rb) vapours has been studied experimentally by means of synchrotron radiation excited photoelectron spectroscopy. Experimental spectra were analyzed by comparing them with available theoretical results and previous experiments. Ionic character of alkali bromides is seen to change in the inner-valence region with increasing atomic number of the alkali atom. A mechanism involving mixing between Br 4s and Rb 4p orbitals has been suggested to account for the fine structure observed in inner-valence ionization region of RbBr. [ABSTRACT FROM AUTHOR]

Published
2014
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10. Relativistic contributions to single and double core electron ionization energies of noble gases.

Author

Niskanen, J., Norman, P., Aksela, H., and Ågren, H.

Subjects
RELATIVITY (Physics), ELECTRON impact ionization, RADIATIVE corrections, NOBLE gases, RELAXATION phenomena, QUANTUM electrodynamics, HAMILTONIAN systems, COULOMB potential, PREDICTION models
Abstract

We have performed relativistic calculations of single and double core 1s hole states of the noble gas atoms in order to explore the relativistic corrections and their additivity to the ionization potentials. Our study unravels the interplay of progression of relaxation, dominating in the single and double ionization potentials of the light elements, versus relativistic one-electron effects and quantum electrodynamic effects, which dominate toward the heavy end. The degree of direct relative additivity of the relativistic corrections for the single electron ionization potentials to the double electron ionization potentials is found to gradually improve toward the heavy elements. The Dirac-Coulomb Hamiltonian is found to predict a scaling ratio of ∼4 for the relaxation induced relativistic energies between double and single ionization. Z-scaling of the computed quantities were obtained by fitting to power law. The effects of nuclear size and form were also investigated and found to be small. The results indicate that accurate predictions of double core hole ionization potentials can now be made for elements across the full periodic table. [ABSTRACT FROM AUTHOR]

Published
2011
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11. Fragmentation patterns of doubly charged acrylonitrile molecule following carbon core ionization.

Author

Itälä, E., Kukk, E., Ha, D. T., Granroth, S., Caló, A., Partanen, L., Aksela, H., and Aksela, S.

Subjects
NUCLEAR fragmentation, SPECTRUM analysis, FRAGMENTATION reactions, DISSOCIATION (Chemistry), PHOTOELECTRON spectroscopy
Abstract

Dissociation of acrylonitrile into pairs of cations and neutral fragments following molecular core ionization was investigated using the photoelectron-photoion-photoion coincidence (PEPIPICO) technique. The fragment ion mass spectra were recorded in coincidence with the carbon 1s photoelectrons. Deuterated and 13C-substituted samples were used for resolving fragment mass ambiguities. Slope analysis of the PEPIPICO patterns was used in determining the fragment separation sequences in case of multiparticle processes. The results show that there are several fragmentation channels producing a wide range of charged coincident fragments. The dynamics of the dominant fragmentation processes is investigated in detail. [ABSTRACT FROM AUTHOR]

Published
2009
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13. Auger decay of the dissociating core-excited states in the HCl and DCl molecules.

Author

Kukk, E., Aksela, H., Sairanen, O.-P., Aksela, S., Kivimäki, A., Nõmmiste, E., Ausmees, A., Kikas, A., Osborne, S. J., and Svensson, S.

Subjects
*AUGER effect, *ELECTRON spectroscopy, *COULOMB excitation, *HYDROGEN chloride, *CHLORIDES
Abstract

High-resolution Auger electron spectra from the decay of the Cl 2p→σ* excitation in HCl and DCl have been measured. The spectra are analyzed, separating molecular and atomic features, which are assigned to transitions to the HCl (5σ2π)4σ* and Cl (3s3p)6 states, respectively. Auger line shapes, as affected by the molecular dissociation, are studied by comparing the experiment with the results of Monte-Carlo computer simulations based on a semiclassical model. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
1996
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14. Shape resonances above the Si 2p threshold in SiF4.

Author

Bancroft, G. M., Aksela, S., Aksela, H., Tan, K. H., Yates, B. W., Coatsworth, L. L., and Tse, J. S.

Subjects
PHOTOELECTRON spectroscopy, RESONANCE, SPECTRUM analysis
Abstract

Using monochromatized synchrotron radiation and angle integrated photoelectron spectroscopy, the Si 2p, Si LVV Auger, and F 2s cross sections have been obtained for SiF4 molecules in the gas phase between 116 and 150 eV photon energies. These cross sections and the Si 2p β value have also been calculated using the MS-Xα method. There is qualitative agreement between theory and experiment. Together with recent experimental and theoretical Si 2p cross sections from SiCl4 and valence band cross sections on SiF4, the two major resonances at 5 and 22 eV kinetic energies are assigned as t2 resonances. The valence band branching ratios are not affected by interchannel coupling above the Si 2p threshold. [ABSTRACT FROM AUTHOR]

Published
1986
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15. Auger energy shifts and core level relaxation energies in XeF2, XeF4, and XeF6.

Author

Aksela, S., Bancroft, G. M., Bristow, D. J., Aksela, H., and Schrobilgen, G. J.

Subjects
PHOTOELECTRONS, XENON, IRON
Abstract

The energy shifts in 3d photoelectron and M4N4,5 N4,5 Auger spectra of Xe have been studied for HXeF2, XeF4, and XeF6 molecules in the gas phase. Using the Auger parameter method, the contributions of the initial state chemical and final state extra-atomic relaxation effects to the observed shifts have been estimated. The relaxation part has found to be significant both in the binding energy (up to 1.8 eV for XeF6) and especially in the Auger shifts. The ground state shifts are thus larger than the 3d binding energy shifts reported earlier. Calculated atomic charges are also now in better agreeement with theory and other experimental values. [ABSTRACT FROM AUTHOR]

Published
1985
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16. The vibrationally resolved participator Auger spectra of selectively excited C 1s(2σ)-12π1 vibrational states in carbon monoxide.

Author

Osborne, S. J., Ausmees, A., Svensson, S., Kivimäki, A., Sairanen, O.-P., de Brito, A. Naves, Aksela, H., and Aksela, S.

Subjects
SPECTRUM analysis, VIBRATIONAL spectra, CARBON monoxide
Abstract

The fully vibrationally resolved participator Auger spectra originating from the decay of the C 1s(2σ)-12π1 resonance in CO are presented. The C 1s(2σ)-12π1 v’=0 resonance has been excited with a 75 meV monochromator bandpass, i.e., in Auger resonant Raman conditions, and the participator Auger spectrum observed. The C 1s(2σ)-12π1 v’=1 resonance is also excited and the corresponding participator Auger spectrum observed with a monochromator bandpass slightly larger than the inherent width. The results are compared to theoretical simulations using coherent lifetime-vibrational interference theory which accounts for the details of the spectrum. We have observed an interference shift on the transitions to different vibrational sublevels in the final state. A high resolution C 1s photoelectron spectrum of CO is also presented. The lifetime width of the C 1s core–hole state is determined to be 97(10) meV, whereas the C 1s(2σ)-12π1 resonance is measured to have a width of 86(10) meV. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
1995
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18. Size-dependent evolution of electronic structure in neutral Pb clusters-As seen by synchrotron-based X-ray photoelectron spectroscopy

Author

Tchaplyguine, M., Ohrwall, G., Andersson, T., Svensson, Svante, Björneholm, Olle, Huttula, M., Mikkela, M., Urpelainen, S., Osmekhin, S., Calo, A., Aksela, S., Aksela, H., Tchaplyguine, M., Ohrwall, G., Andersson, T., Svensson, Svante, Björneholm, Olle, Huttula, M., Mikkela, M., Urpelainen, S., Osmekhin, S., Calo, A., Aksela, S., and Aksela, H.

Abstract

Neutral Pb clusters in the size range from a few tens of atoms up to similar to 100 atoms are studied using synchrotron-based photoelectron spectroscopy. The electronic structure is seen to differ increasingly from that of the solid when the cluster size decreases. The valence band narrows gradually - down to about one fifth of the solid-state band width at the smallest size of few tens of atoms. Simultaneously the Fermi-edge energy shifts further away from the solid value by more than 2 eV. The Pb 5d core level binding energy also increases and the spectral features broaden and change in shape. The changes observed for the valence and for the 5d response energies and shapes are discussed in the context of the metal-to-insulator transition observed earlier in Pb clusters below the critical size of 20-30 atoms/cluster. (C) 2014 Elsevier B.V. All rights reserved.

Published
2014
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19. Multiplet-dependent shake-up structures in high-resolution Auger spectra at 3d−14s24p6np,n=5,6 resonances of Kr

Author

Olsson B, Aksela H, and Bancroft Gm

Subjects
Physics, symbols.namesake, Beamline, Auger effect, Resolution (electron density), symbols, Electron, Atomic physics, Undulator, Multiplet, Atomic and Molecular Physics, and Optics, Spectral line, Auger
Abstract

Shake-up transitions during the Auger decay of the Kr 3d -1 np, n=5,6 resonance states have been studied with high photon and electron resolution (

Published
1992
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21. Size-dependent evolution of electronic structure in neutral Pb clusters—As seen by synchrotron-based X-ray photoelectron spectroscopy

Author

Tchaplyguine, M., primary, Öhrwall, G., additional, Andersson, T., additional, Svensson, S., additional, Björneholm, O., additional, Huttula, M., additional, Mikkelä, M., additional, Urpelainen, S., additional, Osmekhin, S., additional, Caló, A., additional, Aksela, S., additional, and Aksela, H., additional

Published
2014
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22. Interference effects between 2p photoionization and resonant Auger decay channel at 2s-1np (n=4, 5) inner hell resonances in Ar

Author

Sankari R., Kivimäki A., M. Huttula, Matila T., Aksela H., Aksela S., Coreno M., Turri G., Camilloni R., de Simone M., and Prince K.C.

Abstract

The electron spectrum of Ar has been studied in the binding energy region of the 2p213p21np states. These states are populated in direct 2p photoionization accompanied by the 3p!np shake-up transitions. In addition, at photon energies corresponding to the 2s->4p,5p excitations they gain intensity through the 2s21np->2p213p21np resonant Auger decay channels. The two channels can interfere, leading to changes in the intensities of the Ar 2p photoelectron satellites. Experimental results are compared with the results of one-step calculations.

Published
2002
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23. Relative photoionization cross section of Cr atoms in the valence region

Author

Makinen, A., Niskanen, Johannes, Aksela, H., Makinen, A., Niskanen, Johannes, and Aksela, H.

Abstract

In this paper, we report a measurement of a single photoionization cross section of atomic Cr as a function of photon energy between 10 and 35 eV. The result is compared to a semiempirical model employing orbital-based ionization cross-section calculations from the literature. While the wide energy splitting of the singly ionized valence states explains the behavior of the ionization cross section in the lower-energy end, reasons for the mismatch between the calculations and the experiment in the higher-energy end are discussed., QC 20120605

Published
2012
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24. Relativistic contributions to single and double core electron ionization energies of noble gases

Author

Niskanen, Johannes, Norman, Patrick, Aksela, H., Ågren, Hans, Niskanen, Johannes, Norman, Patrick, Aksela, H., and Ågren, Hans

Abstract

We have performed relativistic calculations of single and double core 1s hole states of the noble gas atoms in order to explore the relativistic corrections and their additivity to the ionization potentials. Our study unravels the interplay of progression of relaxation, dominating in the single and double ionization potentials of the light elements, versus relativistic one-electron effects and quantum electrodynamic effects, which dominate toward the heavy end. The degree of direct relative additivity of the relativistic corrections for the single electron ionization potentials to the double electron ionization potentials is found to gradually improve toward the heavy elements. The Dirac-Coulomb Hamiltonian is found to predict a scaling ratio of similar to 4 for the relaxation induced relativistic energies between double and single ionization. Z-scaling of the computed quantities were obtained by fitting to power law. The effects of nuclear size and form were also investigated and found to be small. The results indicate that accurate predictions of double core hole ionization potentials can now be made for elements across the full periodic table., QC 20161222

Published
2011
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25. L1-L2,3-M Coster-Kronig transition in argon

Author

Killy, T., Karvonen, J, Aksela, H, Kivimaki, A., Aksela, S., Camilloni, R., Avaldi, L., Coreno, M., DE SIMONE, M., Richter, R., Prince, K. C., and Stranges, Stefano

Published
1999

26. Experimental and theoretical study of core-valence double photoionization of OCS

Author

Niskanen, J., Carravetta, V., Vahtras, O., Ågren, H., Aksela, H., Andersson, Egil, Hedin, Lage, Linusson, P., Eland, John H. D., Karlsson, Leif, Rubensson, Jan-Erik, Feifel, Raimund, Niskanen, J., Carravetta, V., Vahtras, O., Ågren, H., Aksela, H., Andersson, Egil, Hedin, Lage, Linusson, P., Eland, John H. D., Karlsson, Leif, Rubensson, Jan-Erik, and Feifel, Raimund

Abstract

O 1s, C 1s, and S 2p core-valence double ionization electron spectra of the OCS molecule have been obtained experimentally by a time-of-flight photoelectron-photoelectron coincidence spectroscopy technique. In order to analyze and assign the spectral features observed, we present a protocol for computing core-valence ionization energies of such systems. The protocol is based on a restricted active space multiconfigurational self-consistent field (MCSCF) methodology with a freeze-relax procedure to guarantee a correct core-valence state root index without variational collapse. Corrections for extended dynamical correlation and core-core correlation, respectively, are made by multiconfigurational perturbation theory and by uncontracted basis set Moller-Plesset theory. Envisioning applications to larger molecules, a spin-restricted open-shell density functional method is also applied for the lowest core-valence energies. Furthermore, cross sections through a scheme for computing multiatom Auger transitions generating core-valence holes are presented. We find that the procedure outlined is capable of deriving the energy onset of core-valence ionization within a fraction of an eV and that assignments can be made of the most salient spectral features.

Published
2010
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27. Photoelectron angular distribution and linear magnetic dichroism in the 4p photoemission from Rb atoms

Author

Niskanen, Johannes, Urpelainen, S., Jankala, K., Schulz, J., Heinasmaki, S., Fritzsche, S., Kabachnik, N. M., Aksela, S., Aksela, H., Niskanen, Johannes, Urpelainen, S., Jankala, K., Schulz, J., Heinasmaki, S., Fritzsche, S., Kabachnik, N. M., Aksela, S., and Aksela, H.

Abstract

The angular distribution of photoelectrons and linear magnetic dichroism in the angular distribution for the 4p photoemission from Rb atoms in the ground state, oriented by laser pumping, were measured in the photon energy range from 50 to 100 eV. The experimental results are compared with the multiconfiguration Dirac-Fock (MCDF) calculations. We show that the zero-crossing of the dichroism as a function of energy is connected with the Cooper minimum in the cross section. This fact can be used for an accurate determination of the position of the Cooper minimum., QC 20110210

Published
2010
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28. Valence photoionization of the LiCl monomer and dimer

Author

Niskanen, Johannes, Urpelainen, S., Aksela, S., Aksela, H., Vahtras, O., Carravetta, V., Ågren, Hans, Niskanen, Johannes, Urpelainen, S., Aksela, S., Aksela, H., Vahtras, O., Carravetta, V., and Ågren, Hans

Abstract

This paper reports a study of valence photoionization of the LiCl monomer and dimer. The behavior of the photoionization partial cross section for molecular valence orbitals was measured as a function of photon energy between 15 and 35 eV. A square-integrable-function method was used to model the ionization partial cross section in both the LiCl monomer and dimer., QC 20110103

Published
2010
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29. Valence photoionization and the following fragmentation pathways in Sb-4 clusters

Author

Urpelainen, S., Calo, A., Partanen, L., Huttula, M., Niskanen, Johannes, Kukk, E., Aksela, S., Aksela, H., Urpelainen, S., Calo, A., Partanen, L., Huttula, M., Niskanen, Johannes, Kukk, E., Aksela, S., and Aksela, H.

Abstract

The valence photoelectron spectrum of Sb-4 clusters and the following fragmentation patterns have been studied using synchrotron radiation and electron-ion coincidence technique. An experimental photoelectron spectrum of the 5t(2) ionization of Sb-4 is presented. Theoretical molecular calculations, together with the existing data on the noble gas xenon, were used to describe the experimental results. The bonding properties of the molecular orbitals involved are used to qualitatively describe the dissociation process., QC 20110427

Published
2009
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30. A method to characterize electronic states of 4s ionized Rb by combined laser and synchrotron spectroscopy

Author

Schulz, J., Loos, E., Huttula, M., Heinaesmaeki, S., Svensson, S., Aksela, S., Aksela, H., Schulz, J., Loos, E., Huttula, M., Heinaesmaeki, S., Svensson, S., Aksela, S., and Aksela, H.

Abstract

Photoelectron studies of laser-excited atomic states can reveal more information about the final ionic states than ground-state photoemission. The possibility to tune the laser to distinct fine-structure sub-states of the excited states allows to select specific angular-momentum couplings of the valence electron that are conserved during photoemission. In the 4s photoemission of laser-excited rubidium we use this method to determine the final-state energies and widths of doubly excited ionic states and characterize the angular-momentum couplings.

Published
2008
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32. Valence photoelectron spectra of Na, K, Rb and Cs with s or p outermost electron : Evolution of the states from LS-coupling to jK-coupling

Author

Määttä, M., Schultz, J., Heinäsmäki, S., Aksela, H., Määttä, M., Schultz, J., Heinäsmäki, S., and Aksela, H.

Abstract

The development of the fine structure of the np(5)(n + 1)s and np(5)(n + 1)p (n = 2 in Na, n = 3 in K, n = 4 in Rb, n = 5 in Cs) configurations of alkali atoms ions from LS-coupling to jK-coupling has been studied by comparing the experimental photoelectron spectra with the results obtained with analytical LS-coupling and jK-coupling models.

Published
2007
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33. Shake-up satellites accompanying the inner shell ionization of alkali atoms

Author

Jänkälä, K., Schulz, J., Aksela, H., Jänkälä, K., Schulz, J., and Aksela, H.

Abstract

The shake-up probabilities of the outermost electron in inner shell ionization and subsequent Auger decay of alkali atoms have been studied in the sudden approximation model using the wavefunctions obtained with the multiconfiguration Dirac-Fock (MCDF) method. The tendencies of the shake-up probabilities for both the initially excited and the nonexcited configurations were found to be predicted well in the photoionization by the model used. Based on the calculations, the second shake-up during Auger decay was found to receive considerable high intensity.

Published
2007
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34. 5p photoemission from laser excited cesium atoms

Author

Schulz, J., Määttä, M., Heinäsmäki, S., Huttula, M., Rander, Torbjörn, Svensson, Svante, Aksela, S., Aksela, H., Schulz, J., Määttä, M., Heinäsmäki, S., Huttula, M., Rander, Torbjörn, Svensson, Svante, Aksela, S., and Aksela, H.

Abstract

Fine-structure resolved 5p photoemission spectra of Cs in the ground state and after laser excitation into the [Xe]6p P-2(1/2) and 6p(2)P(3/2) states have been studied. The 5p(5)6p final states have been reached by the 5p(6)6s -> 5p(5)6p conjugate shakeup process from ground-state atoms as well as by direct photoemission from laser-excited atoms. The laser-excited spectra can be well described with calculations based on the jK-coupling model. Calculations based on a multiconfiguration Dirac-Fock approach have been performed to investigate the deviations created by intermediate coupling from the pure jK-coupling scheme.

Published
2006
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35. Characterization of weakly excited final states by shakedown spectroscopy of laser-excited potassium

Author

Schulz, Joachim, Heinäsmäki, Sami, Sankari, Rami, Rander, Torbjörn, Lindblad, Andreas, Bergersen, Henrik, Öhrwall, Gunnar, Svensson, Svante, Kukk, Edwin, Aksela, Seppo, Aksela, H., Schulz, Joachim, Heinäsmäki, Sami, Sankari, Rami, Rander, Torbjörn, Lindblad, Andreas, Bergersen, Henrik, Öhrwall, Gunnar, Svensson, Svante, Kukk, Edwin, Aksela, Seppo, and Aksela, H.

Abstract

3p shakedown spectra of laser excited potassium atoms as well as direct 3p photoemission of ground state potassium have been studied. These two excitation schemes lead to the same final states and thereby provide a good basis for a detailed study of the 3p(5)(4s3d)(1) configurations of singly ionized potassium and the photoemission processes leading to these configurations. The comparison of direct photoemission from the ground state and conjugate shakedown spectra from 4p(1/2) laser excited potassium made it possible to experimentally determine the character of final states that are only weakly excited in the direct photoemission but have a much higher relative intensity in the shakedown spectrum. Based on considerations of angular momentum and parity conservation the excitation scheme of the final states can be understood.

Published
2006
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36. Effects of initial-state laser excitation on inner-shell photoionization and Auger decay of Rb

Author

Jänkälä, K., Schulz, J., Huttula, M., Calo, A., Urpelainen, S., Heinasmäki, S., Fritzsche, S., Svensson, Svante, Aksela, S., Aksela, H., Jänkälä, K., Schulz, J., Huttula, M., Calo, A., Urpelainen, S., Heinasmäki, S., Fritzsche, S., Svensson, Svante, Aksela, S., and Aksela, H.

Abstract

The 3d(-1) photoionization and subsequent M4,5N2,3N2,3 Auger electron spectra of free initially laser-excited rubidium atoms have been investigated. The rubidium atoms were excited from the ground state [Kr]5s(1/2) to the [Kr]5p(1/2) and [Kr]5p(3/2) states. Emphasis was put on the changes in coupling and electron correlation between the three different initial states. The ground state 3d photoelecton spectrum of free Rb atoms was interpreted in detail. The binding energies for 3d(3/2,5/2) orbitals of initially ground-state and laser-excited Rb atoms were obtained. Extensive multiconfiguration Dirac-Fock calculations performed in the relativistic jj coupled basis were compared to the experimental photoelectron and Auger electron spectra.

Published
2006
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38. Laser excitation combined with 2p photoionization and Auger decay of potassium

Author

Jänkälä, K., Sankari, R., Schultz, J., Huttula, M., Caló, A., Heinäsmäki, S., Fritzsche, S., Rander, Torbjörn, Svensson, Svante, Aksela, S., Aksela, H., Jänkälä, K., Sankari, R., Schultz, J., Huttula, M., Caló, A., Heinäsmäki, S., Fritzsche, S., Rander, Torbjörn, Svensson, Svante, Aksela, S., and Aksela, H.

Published
2006

40. Final state selection in the 4p photoemission of Rb by combining laser spectroscopy with soft x-ray photoionization

Author

Schulz, J., Tchaplyguine, M., Rander, Torbjörn, Bergersen, Henrik, Lindblad, Andreas, Öhrwall, Gunnar, Svensson, Svante, Heinäsmäki, S., Sankari, R., Osmekhin, S., Aksela, S., Aksela, H., Schulz, J., Tchaplyguine, M., Rander, Torbjörn, Bergersen, Henrik, Lindblad, Andreas, Öhrwall, Gunnar, Svensson, Svante, Heinäsmäki, S., Sankari, R., Osmekhin, S., Aksela, S., and Aksela, H.

Published
2005

41. Shakedown in core photoelectron spectra from aligned laser excited Na atoms

Author

Scultz, J., Tchaplyguine, M., Rander, Torbjörn, Björneholm, Olle, Svensson, Svante, Sankari, R., Heinäsmäki, S., Kukk, E., Aksela, H., Aksela, S., Scultz, J., Tchaplyguine, M., Rander, Torbjörn, Björneholm, Olle, Svensson, Svante, Sankari, R., Heinäsmäki, S., Kukk, E., Aksela, H., and Aksela, S.

Published
2005

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