Search

The ionization dynamics of Xe cluster was analyzed by extreme ultraviolet (EUV) pump-near infrared (NIR) probe experiments. The experiments were carried out for Xe clusters containing around 5000 atoms on average at the SPring-8 Compact SASE Source (SCSS) test accelerator in Japan. We recorded ion spectra emitted from Xe clusters as a function of the time delay between the EUV and NIR pulses. The ion yields up to highly-charged states were substantially enhanced when Xe clusters excited by the EUV pulses were illuminated by the NIR laser pulses at 1 to 2 ps after the pump pulse, providing a compelling evidence for nano-plasma formation and subsequent NIR absorption via surface plasma resonance. We also observed emergence of low kinetic energy Xe+ at long time delay, which can be attributed to the ionization of excited neutral atoms resulting from the electron-ion recombination in the expanding nano-plasma.

Synopsis Dipole oscillator strengths for the formation of excited hydrogen atom from C2H2 were measured to investigate formation and decay of molecular superexcited states. It seems that non-adiabatic transition plays an important role in the formations of the hot hydrogen atom.

Synopsis We performed a wide-angle X-ray scattering experiment of single Xe nanoparticles using an X-ray free electron laser. We developed a novel analysis method that focuses on the angular correlation between plural Bragg spots in single-shot diffraction patterns. The angular correlations of the Bragg spots encode rich structural information and offer an evidence of twinning and stacking faults in Xe nanoparticles.

Cross sections for the formation of H(2p) atom in photoexcitation were measured for H2 in the lowest rotational level in the energy range of the doubly excited states for examining contribution of the non-adiabatic transition between the 1Σ u − 1Π u doubly excited states.

The angular correlation functions of a pair of Lyman-α photons in the photodissociation of H2 are measured more precisely than in the early experiments [Nakanishi et. al., Phys. Rev. A. 90, 043405(2014)]. The linearly polarized light is used to excite the photodissociation via the doubly excited Q2 1Πu(1) state.

In this contribution, a new time scale named C-fluctuation time is defined by price fluctuations observed at a given resolution. The intraday fractal structures and the relations of the three time scales: real time (physical time), tick time and C-fluctuation time, in foreign exchange markets are analyzed. The data set used is trading prices of foreign exchange rates; US dollar (USD)/Japanese yen (JPY), USD/Euro (EUR), and EUR/JPY. The accuracy of the data is one minute and data within a minute are recorded in order of transaction. The series of instantaneous velocity of C-fluctuation time flowing are exponentially distributed for small C when they are measured by real time and for tiny C when they are measured by tick time. When the market is volatile, for larger C, the series of instantaneous velocity are exponentially distributed.

Symmetry-resolved spectroscopy for investigating the doubly excited states of molecular hydrogen has been newly developed, where a metastable hydrogen atom dissociating in a direction parallel and perpendicular to the electric vector of the linearly polarized incident light is detected.

The cross sections for the generation of a photon-pair from excited fragments in photoexcitation of H2O have been measured as a function of incident photon energy. The multiply excited states of H2O have been observed even above the adiabatic double ionization potential.