| 1. |
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| 2. |
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| 3. |
- Alonso-Mori, R., et al.
(author)
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Towards characterization of photo-excited electron transfer and catalysis in natural and artificial systems using XFELs
- 2016
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In: Faraday discussions. - : Royal Society of Chemistry (RSC). - 1359-6640 .- 1364-5498. ; 194, s. 621-638
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Journal article (peer-reviewed)abstract
- The ultra-bright femtosecond X-ray pulses provided by X-ray Free Electron Lasers (XFELs) open capabilities for studying the structure and dynamics of a wide variety of biological and inorganic systems beyond what is possible at synchrotron sources. Although the structure and chemistry at the catalytic sites have been studied intensively in both biological and inorganic systems, a full understanding of the atomic-scale chemistry requires new approaches beyond the steady state X-ray crystallography and X-ray spectroscopy at cryogenic temperatures. Following the dynamic changes in the geometric and electronic structure at ambient conditions, while overcoming X-ray damage to the redox active catalytic center, is key for deriving reaction mechanisms. Such studies become possible by using the intense and ultra-short femtosecond X-ray pulses from an XFEL, where sample is probed before it is damaged. We have developed methodology for simultaneously collecting X-ray diffraction data and X-ray emission spectra, using an energy dispersive spectrometer, at ambient conditions, and used this approach to study the room temperature structure and intermediate states of the photosynthetic water oxidizing metallo-protein, photosystem II. Moreover, we have also used this setup to simultaneously collect the X-ray emission spectra from multiple metals to follow the ultrafast dynamics of light-induced charge transfer between multiple metal sites. A Mn-Ti containing system was studied at an XFEL to demonstrate the efficacy and potential of this method.
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| 4. |
- Fukuzawa, H., et al.
(author)
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Deep Inner-Shell Multiphoton Ionization by Intense X-Ray Free-Electron Laser Pulses
- 2013
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In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 110:17
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Journal article (peer-reviewed)abstract
- We have investigated multiphoton multiple ionization dynamics of xenon atoms using a new x-ray free-electron laser facility, SPring-8 Angstrom Compact free electron LAser (SACLA) in Japan, and identified that Xen+ with n up to 26 is produced at a photon energy of 5.5 keV. The observed high charge states (n >= 24) are produced via five-photon absorption, evidencing the occurrence of multiphoton absorption involving deep inner shells. A newly developed theoretical model, which shows good agreement with the experiment, elucidates the complex pathways of sequential electronic decay cascades accessible in heavy atoms. The present study of heavy-atom ionization dynamics in high-intensity hard-x-ray pulses makes a step forward towards molecular structure determination with x-ray free-electron lasers. DOI: 10.1103/PhysRevLett.110.173005
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| 5. |
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| 6. |
- Motomura, K., et al.
(author)
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Sequential multiphoton multiple ionization of atomic argon and xenon irradiated by X-ray free-electron laser pulses from SACLA
- 2013
-
In: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 46:16
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Journal article (peer-reviewed)abstract
- We have investigated multiphoton multiple ionization of argon and xenon atoms at 5 keV using a new x-ray free electron laser (XFEL) facility, the SPring-8 Angstrom Compact free electron LAser (SACLA) in Japan. The experimental results are compared with the new theoretical results presented here. The absolute fluence of the XFEL pulse has been determined with the help of the calculations utilizing two-photon processes in the argon atom. The high charge states up to +22 observed for Xe in comparison with the calculations point to the occurrence of sequential L-shell multiphoton absorption and of resonance-enabled x-ray multiple ionization.
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| 7. |
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| 8. |
- Tachibana, T., et al.
(author)
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Nanoplasma Formation by High Intensity Hard X-rays
- 2015
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In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
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Journal article (peer-reviewed)abstract
- Using electron spectroscopy, we have investigated nanoplasma formation from noble gas clusters exposed to high-intensity hard-x-ray pulses at similar to 5 keV. Our experiment was carried out at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility in Japan. Dedicated theoretical simulations were performed with the molecular dynamics tool XMDYN. We found that in this unprecedented wavelength regime nanoplasma formation is a highly indirect process. In the argon clusters investigated, nanoplasma is mainly formed through secondary electron cascading initiated by slow Auger electrons. Energy is distributed within the sample entirely through Auger processes and secondary electron cascading following photoabsorption, as in the hard x-ray regime there is no direct energy transfer from the field to the plasma. This plasma formation mechanism is specific to the hard-x-ray regime and may, thus, also be important for XFEL-based molecular imaging studies. In xenon clusters, photo-and Auger electrons contribute more significantly to the nanoplasma formation. Good agreement between experiment and simulations validates our modelling approach. This has wide-ranging implications for our ability to quantitatively predict the behavior of complex molecular systems irradiated by high-intensity hard x-rays.
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| 9. |
- Berrah, N., et al.
(author)
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Femtosecond-resolved observation of the fragmentation of buckminsterfullerene following X-ray multiphoton ionization
- 2019
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In: Nature Physics. - : Springer Science and Business Media LLC. - 1745-2473 .- 1745-2481. ; 15, s. 1279-1283
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Journal article (peer-reviewed)abstract
- X-ray free-electron lasers have, over the past decade, opened up the possibility of understanding the ultrafast response of matter to intense X-ray pulses. In earlier research on atoms and small molecules, new aspects of this response were uncovered, such as rapid sequences of inner-shell photoionization and Auger ionization. Here, we studied a larger molecule, buckminsterfullerene (C60), exposed to 640eV X-rays, and examined the role of chemical effects, such as chemical bonds and charge transfer, on the fragmentation following multiple ionization of the molecule. To provide time resolution, we performed femtosecond-resolved X-ray pump/X-ray probe measurements, which were accompanied by advanced simulations. The simulations and experiment reveal that despite substantial ionization induced by the ultrashort (20fs) X-ray pump pulse, the fragmentation of C60 is considerably delayed. This work uncovers the persistence of the molecular structure of C60, which hinders fragmentation over a timescale of hundreds of femtoseconds. Furthermore, we demonstrate that a substantial fraction of the ejected fragments are neutral carbon atoms. These findings provide insights into X-ray free-electron laser-induced radiation damage in large molecules, including biomolecules.
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| 10. |
- Fukuzawa, H., et al.
(author)
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Electron spectroscopy of rare-gas clusters irradiated by x-ray free-electron laser pulses from SACLA
- 2016
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In: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 49:3
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Journal article (peer-reviewed)abstract
- We have measured electron energy spectra and asymmetry parameters of Ar clusters and Xe clusters illuminated by intense x-rays at 5 and 5.5 keV. A velocity map imaging spectrometer was developed for this purpose and employed at an x-ray free-electron laser facility, SACLA in Japan. The cluster size dependence and the peak fluence dependence of the electron spectra and asymmetry parameters are discussed.
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| 11. |
- Iablonskyi, D., et al.
(author)
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Interatomic Coulombic Decay Processes after Multiple Valence Excitations in Ne Clusters
- 2015
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In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635, s. 112067-112067
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Conference paper (peer-reviewed)abstract
- We present a comprehensive analysis of autoionization processes in Ne clusters (similar to 5000 atoms) after multiple valence excitations by free electron laser radiation. The evolution from 2-body interatomic Coulombic decay (ICD) to 3-body ICD is demonstrated when changing from surface to bulk Frenkel exciton excitation. Super Coster-Kronig type 2-body ICD is observed at Wannier exciton which quenches the main ICD channel.
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| 12. |
- Iablonskyi, D., et al.
(author)
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Slow Interatomic Coulombic Decay of Multiply Excited Neon Clusters
- 2016
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In: Physical Review Letters. - 0031-9007. ; 117:27
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Journal article (peer-reviewed)abstract
- Ne clusters (∼5000 atoms) were resonantly excited (2p→3s) by intense free electron laser (FEL) radiation at FERMI. Such multiply excited clusters can decay nonradiatively via energy exchange between at least two neighboring excited atoms. Benefiting from the precise tunability and narrow bandwidth of seeded FEL radiation, specific sites of the Ne clusters were probed. We found that the relaxation of cluster surface atoms proceeds via a sequence of interatomic or intermolecular Coulombic decay (ICD) processes while ICD of bulk atoms is additionally affected by the surrounding excited medium via inelastic electron scattering. For both cases, cluster excitations relax to atomic states prior to ICD, showing that this kind of ICD is rather slow (picosecond range). Controlling the average number of excitations per cluster via the FEL intensity allows a coarse tuning of the ICD rate.
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| 13. |
- Ma, R., et al.
(author)
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Photoelectron angular distributions for the two-photon ionization of helium by ultrashort extreme ultraviolet free-electron laser pulses
- 2013
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In: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 46:16
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Journal article (peer-reviewed)abstract
- The two-photon ionization of helium atoms by ultrashort extreme-ultraviolet free-electron laser pulses, produced by the SPring-8 Compact SASE Source test accelerator, was investigated at photon energies of 20.3, 21.3, 23.0 and 24.3 eV. The angular distribution of photoelectrons generated by two-photon ionization is obtained using a velocity map imaging spectrometer. The phase-shift differences and amplitude ratios of the outgoing s and d continuum wave packets are extracted from the photoelectron angular distributions. The obtained values of the phase-shift differences are distinct from scattering phase-shift differences when the photon energy is tuned to a resonance with an excited level or Rydberg manifold. The difference stems from the co-presence of resonant and non-resonant path contributions in the two-photon ionization by femtosecond pulses. Since the relative contribution of both paths can be controlled in principle by the pulse shape, these results illustrate a new way to tailor the continuum wave packet.
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| 14. |
- Nagaya, K., et al.
(author)
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Multiple photoionization of rare-gas clusters by EUV-FEL at Spring-8
- 2012
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In: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 388:3, s. 032082-
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Journal article (peer-reviewed)abstract
- Multiple photoionization processes of giant rare-gas clusters are investigated in the wavelength region of 51 to 61nm at Spring8. We report here some latest results of our investigation; the frustration of photoionization for giant xenon clusters and the charge transfer in Ar-core Ne-shell clusters.
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| 15. |
- Pirozhkov, A. S., et al.
(author)
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Diagnostic of laser contrast using target reflectivity
- 2009
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In: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 94:24
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Journal article (peer-reviewed)abstract
- Using three different laser systems, we demonstrate a convenient and simple plasma based diagnostic of the contrast of high-power short-pulse lasers. The technique is based on measuring the specular reflectivity from a solid target. The reflectivity remains high even at relativistic intensities above 10(19) W/cm(2) in the case of a high-contrast prepulse-free laser. On the contrary, the specular reflectivity drops with increasing intensities in the case of systems with insufficient contrast due to beam breakup and increased absorption caused by preplasma.
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| 16. |
- Takanashi, T, et al.
(author)
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Time-Resolved Measurement of Interatomic Coulombic Decay Induced by Two-Photon Double Excitation of Ne2
- 2017
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In: Physical Review Letters. - 0031-9007. ; 118:3
-
Journal article (peer-reviewed)abstract
- The hitherto unexplored two-photon doubly excited states [Ne∗(2p-13s)]2 were experimentally identified using the seeded, fully coherent, intense extreme ultraviolet free-electron laser FERMI. These states undergo ultrafast interatomic Coulombic decay (ICD), which predominantly produces singly ionized dimers. In order to obtain the rate of ICD, the resulting yield of Ne2+ ions was recorded as a function of delay between the extreme ultraviolet pump and UV probe laser pulses. The extracted lifetimes of the long-lived doubly excited states, 390(-130/+450) fs, and of the short-lived ones, less than 150 fs, are in good agreement with ab initio quantum mechanical calculations.
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| 17. |
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| 18. |
- Gryzlova, E. V., et al.
(author)
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Doubly resonant three-photon double ionization of Ar atoms induced by an EUV free-electron laser
- 2011
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In: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 84:6
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Journal article (peer-reviewed)abstract
- A mechanism for three-photon double ionization of atoms by extreme-ultraviolet free-electron laser pulses is revealed, where in a sequential process the second ionization step, proceeding via resonant two-photon ionization of ions, is strongly enhanced by the excitation of ionic autoionizing states. In contrast to the conventional model, the mechanism explains the observed relative intensities of photoelectron peaks and their angular dependence in three-photon double ionization of argon.
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| 19. |
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| 20. |
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| 21. |
- Mondal, S., et al.
(author)
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Photoelectron angular distributions for the two-photon sequential double ionization of xenon by ultrashort extreme ultraviolet free electron laser pulses
- 2013
-
In: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 46:16
-
Journal article (peer-reviewed)abstract
- Xenon atoms are double-ionized by sequential two-photon absorption by ultrashort extreme ultraviolet free-electron laser pulses with a photon energy of 23.0 and 24.3 eV, produced by the SPring-8 Compact SASE Source test accelerator. The angular distributions of photoelectrons generated by two-photon double ionization are obtained using velocity map imaging. The results are reproduced reasonably well by the present theoretical calculations within the multi-configurational Dirac-Fock approach.
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| 22. |
- Nagaya, K., et al.
(author)
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Formation of the energetic doubly charged ne ion by irradiation of large neon clusters using intense EUV-FEL pulses at 52 nm
- 2010
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In: Journal of Physics: Conference Series. - : Institute of Physics (IOP). - 1742-6596.
-
Conference paper (peer-reviewed)abstract
- The interaction of clusters with intense EUV-FEL pulses was investigated using the SPring-8 Compact SASE Source (SCSS) test facility in Japan. Neon clusters of mean sizes = 1000 and 4000 were irradiated by intense FEL pulses at 52 nm and emitted ions were detected by a momentum imaging spectrometer. The production of energetic doubly charged ions was not found for Ne 1000, but it was observed for Ne 4000 clusters, which suggests that an inhomogeneous charge distribution is generated for the larger clusters.
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| 23. |
- Nagaya, K., et al.
(author)
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Unusual under-threshold ionization of neon clusters studied by ion spectroscopy
- 2013
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In: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 46:16 SI
-
Journal article (peer-reviewed)abstract
- We carried out time-of-flight mass spectrometry for neon clusters that were exposed to intense free electron laser pulses with the wavelength of 62 nm, which induce optical transition from the ground state (2s(2) 2p(6)) to an excited state (2s(2) 2p(5) nl) in the Ne atoms. In contrast to Ne+ ions produced by two-photon absorption from isolated Ne atoms, the Ne+ ion yield from Ne clusters shows a linear dependence on the laser intensity (I). We discuss the ionization mechanisms which give the linear behaviour with respect to I and expected features in the electron emission spectrum.
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| 24. |
- Sugishima, A., et al.
(author)
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Charge and energy transfer in argon-core-neon-shell clusters irradiated by free-electron-laser pulses at 62 nm
- 2012
-
In: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 86:3, s. 033203-
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Journal article (peer-reviewed)abstract
- The multiple ionization of Ar-core-Ne-shell clusters in intense extreme-ultraviolet laser pulses (lambda similar to 62 nm) from the free-electron laser in Japan was investigated utilizing a momentum imaging technique. The Ar composition dependence of the kinetic energies and the yields of the fragment ions give evidence for charge transfer from the Ar core to the Ne shell. We have extended the uniformly charged sphere model originally applied to pristine clusters [Islam et al., Phys. Rev. A 73, 041201 (R) (2006)] to the core-shell heterogeneous clusters to estimate the amounts of charge and energy transfers.
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| 25. |
- Yamada, A., et al.
(author)
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Ion-ion coincidence studies on multiple ionizations of N-2 and O-2 molecules irradiated by extreme ultraviolet free-electron laser pulses
- 2010
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In: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 132:20, s. 204305-
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Journal article (peer-reviewed)abstract
- We have investigated multiple ionization of N-2 and O-2 molecules by 52 nm extreme-ultraviolet light pulses at the free-electron laser facility SCSS in Japan. Coulomb break-up of parent ions with charge states up to 5+ is found by the ion-ion coincidence technique. The charge-state dependence of kinetic energy release distributions suggests that the electrons are emitted sequentially in competition with the elongation of the bond length.
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| 26. |
- Zhaunerchyk, Vitali, et al.
(author)
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Disentangling formation of multiple-core holes in aminophenol molecules exposed to bright X-FEL radiation
- 2015
-
In: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:24
-
Journal article (peer-reviewed)abstract
- Competing multi-photon ionization processes, some leading to the formation of double core hole states, have been examined in 4-aminophenol. The experiments used the linac coherent light source (LCLS) x-ray free electron laser, in combination with a time-of-flight magnetic bottle electron spectrometer and the correlation analysis method of covariance mapping. The results imply that 4-aminophenol molecules exposed to the focused x-ray pulses of the LCLS sequentially absorb more than two x-ray photons, resulting in the formation of multiple core holes as well as in the sequential removal of photoelectrons and Auger electrons (so-called PAPA sequences).
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| 27. |
- Frasinski, L. J., et al.
(author)
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Dynamics of Hollow Atom Formation in Intense X-Ray Pulses Probed by Partial Covariance Mapping
- 2013
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In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 111:7, s. 073002-
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Journal article (peer-reviewed)abstract
- When exposed to ultraintense x-radiation sources such as free electron lasers (FELs) the innermost electronic shell can efficiently be emptied, creating a transient hollow atom or molecule. Understanding the femtosecond dynamics of such systems is fundamental to achieving atomic resolution in flash diffraction imaging of noncrystallized complex biological samples. We demonstrate the capacity of a correlation method called partial covariance mapping'' to probe the electron dynamics of neon atoms exposed to intense 8 fs pulses of 1062 eV photons. A complete picture of ionization processes competing in hollow atom formation and decay is visualized with unprecedented ease and the map reveals hitherto unobserved nonlinear sequences of photoionization and Auger events. The technique is particularly well suited to the high counting rate inherent in FEL experiments.
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| 28. |
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| 29. |
- Mucke, Melanie, et al.
(author)
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Covariance mapping of two-photon double core hole states in C2H2 and C2H6 produced by an x-ray free electron laser
- 2015
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In: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 17
-
Journal article (peer-reviewed)abstract
- Few-photon ionization and relaxation processes in acetylene (C2H2) and ethane (C2H6) were investigated at the linac coherent light source x-ray free electron laser (FEL) at SLAC, Stanford using a highly efficient multi-particle correlation spectroscopy technique based on a magnetic bottle. The analysis method of covariance mapping has been applied and enhanced, allowing us to identify electron pairs associated with double core hole (DCH) production and competing multiple ionization processes including Auger decay sequences. The experimental technique and the analysis procedure are discussed in the light of earlier investigations of DCH studies carried out at the same FEL and at third generation synchrotron radiation sources. In particular, we demonstrate the capability of the covariance mapping technique to disentangle the formation of molecular DCH states which is barely feasible with conventional electron spectroscopy methods.
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| 30. |
- Zhaunerchyk, Vitali, et al.
(author)
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Using covariance mapping to investigate the dynamics of multi-photon ionization processes of Ne atoms exposed to X-FEL pulses
- 2013
-
In: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 46:16, s. 164034-
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Journal article (peer-reviewed)abstract
- We report on a detailed investigation into the electron emission processes of Ne atoms exposed to intense femtosecond x-ray pulses, provided by the Linac Coherent Light Source Free Electron Laser (FEL) at Stanford. The covariance mapping technique is applied to analyse the data, and the capability of this approach to disentangle both linear and nonlinear correlation features which may be hidden on coincidence maps of the same data set is demonstrated. Different correction techniques which enable improvements on the quality of the spectral features extracted from the covariance maps are explored. Finally, a method for deriving characteristics of the x-ray FEL pulses based on covariance mapping in combination with model simulations is presented.
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| 31. |
- Kornilov, O., et al.
(author)
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Coulomb explosion of diatomic molecules in intense XUV fields mapped by partial covariance
- 2013
-
In: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 46:16
-
Journal article (peer-reviewed)abstract
- Single-shot time-of-flight spectra for Coulomb explosion of N-2 and I-2 molecules have been recorded at the Free Electron LASer in Hamburg (FLASH) and have been analysed using a partial covariance mapping technique. The partial covariance analysis unravels a detailed picture of all significant Coulomb explosion pathways, extending up to the N4+-N5+ channel for nitrogen and up to the I8+-I9+ channel for iodine. The observation of the latter channel is unexpected if only sequential ionization processes from the ground state ions are considered. The maximum kinetic energy release extracted from the covariance maps for each dissociation channel shows that Coulomb explosion of nitrogen molecules proceeds much faster than that of the iodine. The N-2 ionization dynamics is modelled using classical trajectory simulations in good agreement with the outcome of the experiments. The results suggest that covariance mapping of the Coulomb explosion can be used to measure the intensity and pulse duration of free-electron lasers.
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| 32. |
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| 33. |
- Sanchez-Gonzalez, A., et al.
(author)
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Accurate prediction of X-ray pulse properties from a free-electron laser using machine learning
- 2017
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8
-
Journal article (peer-reviewed)abstract
- Free-electron lasers providing ultra-short high-brightness pulses of X-ray radiation have great potential for a wide impact on science, and are a critical element for unravelling the structural dynamics of matter. To fully harness this potential, we must accurately know the X-ray properties: intensity, spectrum and temporal profile. Owing to the inherent fluctuations in free-electron lasers, this mandates a full characterization of the properties for each and every pulse. While diagnostics of these properties exist, they are often invasive and many cannot operate at a high-repetition rate. Here, we present a technique for circumventing this limitation. Employing a machine learning strategy, we can accurately predict X-ray properties for every shot using only parameters that are easily recorded at high-repetition rate, by training a model on a small set of fully diagnosed pulses. This opens the door to fully realizing the promise of next-generation high-repetition rate X-ray lasers.
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| 34. |
- Sanchez-Gonzalez, A., et al.
(author)
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Auger electron and photoabsorption spectra of glycine in the vicinity of the oxygen K-edge measured with an X-FEL
- 2015
-
In: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:23
-
Journal article (peer-reviewed)abstract
- We report the first measurement of the near oxygen K-edge auger spectrum of the glycine molecule. Our work employed an x-ray free electron laser as the photon source operated with input photon energies tunable between 527 and 547 eV. Complete electron spectra were recorded at each photon energy in the tuning range, revealing resonant and non-resonant auger structures. Finally ab initio theoretical predictions are compared with the measured above the edge auger spectrum and an assignment of auger decay channels is performed.
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| 35. |
- Gono, Y., et al.
(author)
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Systematics of high-spin isomers in N=83 isotones and a high-spin isomer beam
- 2002
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In: European Physical Journal A. - 1434-6001 .- 1434-601X. ; 13:02-jan, s. 5-8
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Journal article (peer-reviewed)abstract
- Isomers in N = 83 isotones of Z = 60 66 were studied systematically. Their spins and parities arc,49/2(+) and 27(+) for odd and odd-odd nuclei, respectively. Nearly constant excitation energies of these isomers indicated a decrease of a Z = 64 shell gap energy as Z decreases from 64 to 60 within the framework of a deformed independent-particle model (DIPM). Their configurations are [v(f(tau/2)h(9/2)i(13/2)), pi(h(11/2))(2)](49/2+) and [v(f(7/2)h(9/2)i(13/2)), pi(h(11/2))(2)(d(5/2))(-1)](27+) for odd and odd-odd nuclei, respectively. The shape of the yrast status changes suddenly at spin 49/2(odd) and 27(odd-odd) from a near spherical to an oblate shape. Transitions from isomers are highly hindered because of the shape changes. They may be categorized to be shape isomers. The development of a secondary beam produced by using these high-spin isomers is also described.
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| 36. |
- Kishida, T., et al.
(author)
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High-spin isomeric beam line
- 2002
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In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 484:03-jan, s. 45-55
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Journal article (peer-reviewed)abstract
- A high-spin isomeric beam line has been constructed at RIKEN based on the inverse kinematics of fusion-evaporation reactions. The beam line provides high-spin isomers as secondary beams, whose intensity is more than 10(5) sec(-1). The characteristics and the present status of the beam line are described.
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| 37. |
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