A5036071424- Advanced Chemical Physics Studies
- Atomic and Molecular Physics
- Mass Spectrometry Techniques and Applications
- Laser-Matter Interactions and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Spectroscopy and Laser Applications
- Advanced X-ray Imaging Techniques
- Electron and X-Ray Spectroscopy Techniques
- Particle Accelerators and Free-Electron Lasers
- Advanced Electron Microscopy Techniques and Applications
- Quantum, superfluid, helium dynamics
- Ion-surface interactions and analysis
- Cold Atom Physics and Bose-Einstein Condensates
- Semiconductor materials and devices
- Photochemistry and Electron Transfer Studies
- Spectroscopy and Quantum Chemical Studies
- Atomic and Subatomic Physics Research
- Laser-induced spectroscopy and plasma
- Laser Design and Applications
- Radioactive element chemistry and processing
- Quantum optics and atomic interactions
- Catalytic Processes in Materials Science
- Atmospheric Ozone and Climate
- Complementary and Alternative Medicine Studies
- Nuclear Materials and Properties
SPring-8
2013-2024
National Institutes for Quantum Science and Technology
2016-2024
Japan Synchrotron Radiation Research Institute
2006-2019
Japan Atomic Energy Agency
2008-2014
RIKEN
2013
Mexican Social Security Institute
2003-2006
High Energy Accelerator Research Organization
2004-2005
Queen's University Belfast
2003
Bonneville Power Administration
1997
King George Hospital
1963-1964
The concept, design and performance of Japan's compact free-electron laser (FEL) facilities, the SPring-8 Compact SASE Source test accelerator (SCSS) Angstrom free electron LAser (SACLA), their applications in mainly atomic, molecular optical science are reviewed. At SCSS, intense, ultrafast FEL pulses at extreme ultraviolet (EUV) wavelengths have been utilized for investigating various multi-photon processes atoms, molecules clusters by means ion spectroscopy. quantum effect...
Electron beam ion traps (EBITs) are ideal tools for both production and study of highly charged ions (HCIs). In order to reduce their construction, maintenance, operation costs, we have developed a novel, compact, room-temperature design, the Heidelberg Compact EBIT (HC-EBIT). Four already commissioned devices operate at strongest fields (up 0.86 T) reported such EBITs using permanent magnets, run electron currents up 80 mA, energies 10 keV. They demonstrate HCI production, trapping,...
We present results from an experimental ion imaging study into the fragmentation dynamics of 1-iodopropane and 2-iodopropane following interaction with extreme ultraviolet intense femtosecond laser pulses a photon energy 95 eV. Using covariance analysis, range observed pathways resulting polycations can be isolated interrogated in detail at relatively high count rates (∼12 ions shot-1). By incorporating recently developed native frames analysis approach three-dimensional procedure,...
We have measured the vibrational structures of N 1s photoelectron mainline and satellites gaseous N2 molecule with resolution better than 75 meV. The gerade ungerade symmetries core-ionized (mainline) states are resolved energetically, symmetry-dependent angular distributions for satellite emission allow us to resolve Sigma Pi shake-up (satellite) states. Symmetry-adapted cluster-expansion configuration-interaction calculations potential energy curves along a Franck-Condon analysis well...
The carbon 1s photoelectron spectrum of CF4 measured at photon energies from 330to1500eV shows significant contributions nonsymmetric vibrational modes. These increase linearly as the energy increases. excitation these modes, which is not predicted in usual Franck–Condon point view, arises recoil momentum imparted to atom ionization process. A theory presented for quantitative prediction effect; predictions this are agreement measurements. experiments also yield frequencies symmetric and...
We have observed and characterized 501.6 nm collective spontaneous emission (superfluorescence) following $1{s}^{2}\ensuremath{\rightarrow}1s3p$ excitation of helium atoms by 53.7 free-electron laser radiation. Emitted pulse energies up to 100 nJ are observed, corresponding a photon number conversion efficiency $10%$. observe the peak intensity scale as ${\ensuremath{\rho}}^{2}$ emitted width delay ${\ensuremath{\rho}}^{\ensuremath{-}1}$, where $\ensuremath{\rho}$ is atom density. pulses...
We report an experimental and numerical study of the propagation free-electron laser pulses (wavelength 24.3 nm) through helium gas. Ionization excitation populates ${\mathrm{He}}^{+}$ $4p$ state. Strong, directional emission was observed at wavelengths 469, 164, 30.4, 25.6 nm. interpret emissions 469 164 nm as $4p\text{}\text{\ensuremath{-}}3s\text{\ensuremath{-}}2p$ cascade superfluorescence, that 30.4 yoked superfluorescence on $2p\text{\ensuremath{-}}1s$ transition, free-induction decay $3p$
The photodissociation dynamics of strong-field ionized methyl iodide were probed using intense extreme ultraviolet (XUV) radiation produced by the SPring-8 Angstrom Compact free electron LAser.
In an aim to create a "sharp" molecular knife, we have studied site-specific fragmentation caused by Si:2p core photoionization of bridged trihalosilyltrimethylsilyl molecules in the vapor phase. Highly bond dissociation has been found occur around core-ionized Si site some studied. The specificity and 2p binding energy difference between two sites depend similar ways on intersite bridge electronegativities included halogen atoms. present experimental computational results show that for...
The molecular-frame photoelectron angular distributions (MFPADs) in O 1s photoemission from CO2 molecule were measured. Patterns due to diffractions observed the MFPADs. polarization-averaged MFPADs compared with theoretical calculation and found be useful determining molecular bond-length, which is a component determine structures.
Site-specific fragmentation caused by $\mathrm{Si}:2p$ core-level photoionization of ${\mathrm{F}}_{3}{\mathrm{SiCH}}_{2}{\mathrm{CH}}_{2}\mathrm{Si}({\mathrm{CH}}_{3}{)}_{3}$ vapor was studied means high-resolution energy-selected-electron photoion-photoion triple-coincidence spectroscopy. The ab initio molecular orbital method used for the theoretical description. ${{\mathrm{F}}_{3}{\mathrm{SiCH}}_{2}{\mathrm{CH}}_{2}}^{+}\text{\ensuremath{-}}{\mathrm{Si}({\mathrm{CH}}_{3}{)}_{3}}^{+}$ ion...
The energy band structure of SiO2/4H-SiC fabricated on (0001) Si- and (000-1) C-face substrates was investigated by means synchrotron radiation x-ray photoelectron spectroscopy (SR-XPS). found to be dependent substrate orientation oxide thickness due both intrinsic extrinsic effects that cause charge transfer at the SiO2/SiC interface. Our SR-XPS analysis revealed conduction offset for is smaller than Si-face. This that, whereas exhibit high carrier mobility, a problem crucial gate...
C-I bond extension and fission following ultraviolet (UV, 262 nm) photoexcitation of 2- 3-iodothiophene is studied using ultrafast time-resolved extreme (XUV) ionization in conjunction with velocity map ion imaging. The photoexcited molecules eventual I atom products are probed by site-selective at the 4d edge intense XUV pulses, which induce multiple charges initially localized to iodine atom. At separations below critical distance for charge transfer (CT), can redistribute around molecule...
We present results from a covariance ion imaging study, which employs extensive filtering, on the relationship between fragment momenta to gain deeper insight into photofragmentation dynamics. A new data analysis approach is introduced that considers momentum partitioning fragments of breakup molecular polycation disentangle concurrent fragmentation channels, yield same species. exploit this examine exchange products, provides direct dynamics fragmentation. apply these techniques extensively...
We report the first experimental measurements of effect an applied field on photoexcitation and autoionization doubly excited states helium. Ground-state photoionization spectra have been measured in region below He+(N=2) threshold with static electric fields up to 84.4 kV/cm across interaction region. The results are compared theoretical calculations Chung et al. [J. Phys. B 34, 165 (2001)]], which only available this regime. Transitions several N=2, n=6 manifold assigned, a wealth new...
Extreme ultraviolet (EUV) fluorescence emitted from Ar clusters irradiated by intense EUV free electron laser (FEL) pulses has been investigated. The spectra display rich structure at wavelengths shorter than the incident FEL wavelength of 51 nm. results suggest that multiply-charged ions are produced following ion-electron recombination processes which occur in nanoplasma created multi-photon excitation during EUV-FEL pulses.
We have identified interatomic Coulombic decay (ICD) processes in the ArKr dimer following Ar 2p Auger decay, using momentum-resolved electron–ion–ion coincidence spectroscopy and simultaneously determining kinetic energy of ICD electron KER between Ar2+ Kr+. find that spin-conserved which Ar2+(3p−33d) 1P 3P to Ar2+(3p−2)1D 3P, respectively, ionizing Kr atom, are significantly stronger than spin-flip Ar2+(3p−2)3P 1D, respectively.
Two recent theoretical studies [C. Liu, Phys. Rev. A 64, 010501 (2001)]; M. Zitnik, ibid. 65, 032520 (2002)]] predict that the fluorescence lifetimes of helium doubly excited states converging to He+ N=2 should be longer than 2p ion state. This effect is caused by electric field outer electron which, through Stark mixing, gives inner fluorescing some series specific, stabilizing 2s character. We have obtained first experimental evidence confirms this measuring lifetime 2p3d(1P0) was...
We present extreme-ultraviolet (EUV) fluorescence spectra of Ar clusters irradiated by intense EUV free-electron-laser (FEL) pulses focused to intensities up $3\ifmmode\times\else\texttimes\fi{}{10}^{13}\phantom{\rule{0.16em}{0ex}}\mathrm{W}/{\mathrm{cm}}^{2}$ at a wavelength 51 nm. The reveal wavelengths shorter than that the incident radiation, which can be assigned lines from excited multiply charged ions $\mathrm{A}{\mathrm{r}}^{z+*}$ with $z$ as high 6. This demonstrates charge states...
CARCINOMA OF LUNG >BRrm before there is any feeling of security.In the 1949-50 series 40% patients were alive at end two years and 34% three years.If these figures follow pattern other group it would seem reasonable to suggest that a 25% survival five might be expected.Many those who have died are known from causes than recurrence cancer lung; suicide, accident, old age all played ssme part in reducing number survivors.A nave exceeded five-year period lived longer this arbitrary limit.My...
Inner-shell excitation spectra and fragmentation of small clusters formic acid have been studied in the oxygen K-edge region by time-of-flight fragment mass spectroscopy. In addition to several cations smaller than parent molecule, we identified production HCOOH∙H+ H3O+ characteristic proton transfer reactions within clusters. Cluster-specific generated monitoring partial ion yields product cations. Resonance transitions O1s(CO∕OH) electrons into πCO* orbital preedge were found shift energy...