Photoelectron angular distribution studies for two spin\u2013orbit-split components of Xe 3d subshell: a critical comparison between theory and experiment

The photoelectron angular distribution asymmetry parameters \u3b2 of the Xe 3d subshell were investigated using an x-ray free-electron laser (XFEL) at photon energies of 750 and 800 eV. Owing to the perfect polarization of the XFEL and two-dimensional momentum imaging capability of our velocity map imaging spectrometer, we determined the \u3b2 values with high accuracy. The \u3b2 values were also investigated based on relativistic time-dependent density functional theory calculations of up to 900 eV of photon energies. By comparing all the available experimental results including our data with the most reliable theories on the photon energy dependence of the \u3b2 parameters, serious differences are noted between the experiments and theories. Further studies on resolving this difference will provide new insight into the photoionization processes of the deep inner shells

Development and Test Results of a low-β\beta Quadrupole Model for the Large Hadron Collider

A 1-m model of the high gradient 70 mm aperture superconducting low-b quadrupoles for the Large Hadron Collider (LHC) has been developed. A field gradient of 250 T/m at 1.9 K has been achieved with a peak field of 10 T in the coil. This paper describes development of the first model magnet and presents the test results

Development of the RF Separator for the Secondary Beam from the Incident Particles

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Electronic States of Cobalt Cluster Cations : Absorption Spectrum of d Electrons and Spin-polarized DV-Xα Calculation

Photodissociation spectra of cobalt cluster ion-argon atom complexes, Co^+_nAr (n=3-5), were measured by detecting the product ions Co^+_n and Co^+_, with a tunable laser pulse from an optical parametric oscillator in the photon-energy range from 0.7 to 2.8 eV. The photodissociation spectra thus obtained are equivalent to the optical absorption spectra of the underlying cobalt cluster ions, Co^+_n, because the argon atom is weakly bound to Co^+_n. The spectrum was analyzed by means of a spin-polarized DV-Xα calculation, and the electronic and the geometric structures of Co^+_3 and Co^+_4 were determined. The analysis shows that all the transitions in the entire energy range studied occur between occupied and unoccupied energy levels associated with 3d atomic orbitals (AOs) having the minority spin. The spin difference (difference in population per Co atom between the majority and the minority spins) was evaluated from the electronic structures thus obtained. The spin differences of 2.00 for Co^+_3 and 1.75 for Co^+_4 indicate ferromagnetic spin coupling in these cobalt cluster ions

Pseudo-orthogonalization of memory patterns for complex-valued and quaternionic associative memories

Hebbian learning rule is well known as a memory storing scheme for associative memory models. This scheme is simple and fast, however, its performance gets decreased when memory patterns are not orthogonal each other. Pseudo-orthogonalization is a decorrelating method for memory patterns which uses XNOR masking between the memory patterns and randomly generated patterns. By a combination of this method and Hebbian learning rule, storage capacity of associative memory concerning non-orthogonal patterns is improved without high computational cost. The memory patterns can also be retrieved based on a simulated annealing method by using an external stimulus pattern. By utilizing complex numbers and quaternions, we can extend the pseudo-orthogonalization for complex-valued and quaternionic Hopfield neural networks. In this paper, the extended pseudo-orthogonalization methods for associative memories based on complex numbers and quaternions are examined from the viewpoint of correlations in memory patterns. We show that the method has stable recall performance on highly correlated memory patterns compared to the conventional real-valued method

Output Estimation of Concentrator Photovoltaic Using Mappings of Environmental Factors and Performance Ratio

Estimation of the output energy of concentrator photovoltaic system is difficult, because the output energy of concentrator photovoltaic system installed outdoors is influenced by various environmental factors. A new method to estimate the output energy is proposed using a contour map of environmental factors. The contour map of estimated output energy was quite similar to that of experimentally-measured output energy. The error ratio of the estimated output energy to the actual output energy was only - 0.14%. The result indicates that this method is useful to estimate the output energy of CPV systems