XATOM: all about x-ray atomic physics

XATOM is an integrated toolkit for x-ray atomic physics. It mainly focuses on what are fundamental x-ray-induced atomic processes and how their dynamics evolve during x-ray free electron laser (FEL) pulses. To treat x-ray–atom interactions, we employ a consistent theoretical framework based on nonrelativistic quantum electrodynamics and perturbation theory, within the Hartree-Fock-Slater model. This toolkit can easily handle all possible n-hole electronic configurations of all possible +n charge states of any elements. With XATOM, one can calculate photoionization cross sections, Auger and Coster-Kronig decay rates, fluorescence rates, elastic x-ray scattering cross sections and their dispersion correction, and shake-off branching ratios. With XATOM, the ionization and relaxation dynamics are described by rate equations, which are solved by either direct solver for an N by N matrix or Monte-Carlo solver [6] for a huge number of coupled rate equations. After solving rate equations, one can investigate, for example, scattering patterns including electronic radiation damage [1], charge state distribution [2,4,6], pathways to reach high charge states [2,4,6], MAD coefficients and wavelength-dependent scattering patterns [3], and photoelectron / Auger electron / fluorescence spectra [4,6].

Diagrams of x-ray–atom interaction. P: photoionization, A: Auger (Coster-Kronig) decay, F: fluorescence, SO: shake-off, S: elastic x-ray scattering, and RS: resonant elastic x-ray scattering.

1. Sang-Kil Son, Linda Young, and Robin Santra, Impact of hollow-atom formation on coherent x-ray scattering at high intensity, Phys. Rev. A 83, 033402 (2011) [BibTeX][link][pdf][abstract]
2. Gilles Doumy, C. Roedig, Sang-Kil Son, C. I. Blaga, A. D. DiChiara, Robin Santra, N. Berrah, C. Bostedt, J. D. Bozek, P. H. Bucksbaum, J. P. Cryan, L. Fang, S. Ghimire, J. M. Glownia, M. Hoener, E. P. Kanter, B. Krässig, M. Kuebel, M. Messerschmidt, G. G. Paulus, D. A. Reis, N. Rohringer, L. Young, P. Agostini, and L. F. DiMauro, Nonlinear atomic response to intense ultrashort x rays, Phys. Rev. Lett. 106, 083002 (2011) [BibTeX][link][pdf][abstract]
3. Sang-Kil Son, Henry N. Chapman, and Robin Santra, Multiwavelength anomalous diffraction at high x-ray intensity, Phys. Rev. Lett. 107, 218102 (2011) [BibTeX][link][pdf][abstract]
4. Benedikt Rudek, Sang-Kil Son, Lutz M. Foucar, Sascha W. Epp, Benjamin Erk, Robert Hartmann, Marcus Adolph, Robert Andritschke, Andrew Aquila, Nora Berrah, Christoph Bostedt, John Bozek, Nicola Coppola, Frank Filsinger, Hubert Gorke, Tais Gorkhover, Heinz Graafsma, Lars Gumprecht, Andreas Hartmann, Günter Hauser, Sven Herrmann, Helmut Hirsemann, Peter Holl, André Hömke, Loic Journel, Christian Kaiser, Nils Kimmel, Faton Krasniqi, Kai-Uwe Kühnel, Michael Matysek, Marc Messerschmidt, Danilo Miesner, Thomas Möller, Robert Moshammer, Kiyonobu Nagaya, Björn Nilsson, Guillaume Potdevin, Daniel Pietschner, Christian Reich, Daniela Rupp, Gerhard Schaller, Ilme Schlichting, Carlo Schmidt, Florian Schopper, Sebastian Schorb, Claus-Dieter Schröter, Joachim Schulz, Marc Simon, Heike Soltau, Lothar Strüder, Kiyoshi Ueda, Georg Weidenspointner, Robin Santra, Joachim Ullrich, Artem Rudenko, and Daniel Rolles, Ultra-efficient ionization of heavy atoms by intense X-ray free-electron laser pulses, (submitted, 2012) [BibTeX]
5. Arina Sytcheva, Stefan Pabst, Sang-Kil Son, and Robin Santra, Enhanced nonlinear response of Ne⁸⁺ to intense ultrafast x rays, Phys. Rev. A 85, 023414 (2012) [BibTeX][link][pdf][abstract]
6. Sang-Kil Son and Robin Santra, Monte-Carlo calculation of ion, electron, and photon spectra of xenon atoms in x-ray free-electron laser pulses, (submitted, 2012) [BibTeX][abstract]

1. Sang-Kil Son, Electronic response to X-ray free-electron laser pulses in The 3rd CQSE International Workshop on Atomic, Molecular, and Ultrafast Science and Technology (National Taiwan University, Taipei, Taiwan, January 7-8, 2012) [invited talk] [BibTeX][link][pdf][slide: 9Mb][abstract]

1. Sang-Kil Son and Robin Santra, XATOM: an integrated toolkit for X-ray and atomic physics in 1st CFEL-Symposium 2011 (CFEL, Sylt, Germany, March 18-20, 2011) [BibTeX][poster: 3Mb][abstract]
2. Sang-Kil Son and Robin Santra, XATOM: an integrated toolkit for X-ray and atomic physics in The 17th International Conference on Atomic Processes in Plasmas (Queen's University, Belfast, UK, July 19-22, 2011) [BibTeX][link][pdf][poster: 4Mb][abstract]
3. Sang-Kil Son and Robin Santra, XATOM: an integrated toolkit for X-ray and atomic physics in The 3rd CQSE International Workshop on Atomic, Molecular, and Ultrafast Science and Technology (National Taiwan University, Taipei, Taiwan, January 7-8, 2012) [BibTeX][link][poster: 4Mb][abstract]