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[en] The characteristic X-ray intensities of Ag-Lα, Lβ1, Lβ2 and Lγ1 are measured in electron-impact ionization at energy of 10 keV. The emission angle in this work ranges from 0° to 20° at interval of 5°. The angular dependence of L X-ray intensity ratios has been investigated for Lα / Lβ1, Lβ2 / Lβ1 and Lγ1 / Lβ1. It is found from the experimental results that the emissions of Lβ1, Lβ2 and Lγ1 X-rays are spatially isotropic, while the Lα X-rays exhibit anisotropic emission. Consequently, the alignment behavior of vacancy states is discussed with thorough analysis of vacancy transfer process. - Highlights: • Only the Lα X-rays are found to be spatially anisotropic in the measurement. • The alignment of L3-subshell is influenced by vacancy transfer process. • Different alignment behaviors in previous work have been clarified.
[en] Classical dynamics simulations of sputtering have been carried out for 3 keV Ar projectiles incident on Cu(1 0 0) crystallite targets with a range of lateral and vertical dimensions. The purpose of the simulations was to document the effects of containment failure on the predicted sputter yields and to establish criteria for convergence of the predicted sputtering properties to asymptotic values. Failure of lateral containment produces sputter yield errors due to both lateral truncation of the target (which understates yields) and to sputtering from the edge faces of the target crystallite (which overstates yields). Failure of vertical containment understates sputter yields. For practical purposes, sputter yield containment can be achieved using a 12-layer Cu(1 0 0) target with 441 atoms per layer, provided that the contribution from atoms originating from the crystallite edge faces is excluded from the sputter yield estimates
[en] The assignment of the value for spin to a large number of resonances makes it possible to study various quantities as a function of the two spin states, J = I ± 1/2. The authors observed, in particular, the strength function S0 for target nuclei of spin I = 1/2 (Y, Ag, Tm, Pt). S0 is the same for the spins J = 0 and J = 1. For target nuclei of spin I = 3/2 (Cl, Cu, Ga, As, Br, Ba, Au), S0 for spin state J=2 is twice as large as for J = 1. There is a discussion of the results obtained in the energy range of a few keV. (author)
[fr]L'attribution de la valeur du spin a un grand nombre de resonances permet l'etude de differentes quantites en fonction des deux etats de spin J= I ± 1/2. La fonction densite S0 a ete en particulier etudiee pour des noyaux cibles de spin I = 1/2 (Y, Ag, Tm, Pt); la valeur S0 est la meme pour les valeurs de spin J = 0 et J = 1. Pour les noyaux cibles I = 3/2 (Cl, Cu, Ga, As, Br, Ba, Au), la valeur S0 pour l'etat de spin J = 2 est deux fois plus grande que la valeur S0 pour J= 1. Les resultats obtenus dans le domaine d'energie de quelques keV sont presentes et discutes. (author)
[en] Highlights: • SDCT provides excellent image quality at low keV levels. • SDCT enables the assessment of arteries in venous phase. • MonoE imaging from SDCT showed distinct different luminal diameters than conventional imaging. - Abstract: ObjectivesTo investigate the utilization of virtual mono-energetic images (MonoE) at low kiloelectron volt (keV) levels derived from a dual-layer spectral detector CT (SDCT) for the assessment of abdominal arteries in venous contrast phase scans using arterial phase imaging as an internal reference standard.
[en] Complete text of publication follows. Investigations of the interactions of highly charged ions (HCI) with internal surfaces recently became available due to the advances in the fabrication of nano-, micro-, and macrocapillaries. In contrast to the case of metallic capillaries, the experiments with insulating ones showed not only directional guiding of the ions, but also the remarkable fact that the ions keep their initial charge state as a consequence of a self-organized charge-up inside the capillary. Following the pioneering work of Stolterfoht et al. several groups studied the ion guiding through insulating foils with randomly distributed capillaries or ordered arrays of regular nanocapillaries. It follows from the type of the used samples, collective effects due to the presence of neighboring capillaries must be taken into account for an accurate simulation of the ion trajectories. These collective effects make a full theoretical description of the interaction between charged particles and insulator capillary walls rather difficult. In order to obtain an easier situation for comparison with simulation, we investigated the transmission of Ar9+ ions through a single, cylindrical-shaped glass capillary of macroscopic dimensions, thus avoiding these collective effects. For our investigations we used a single macroscopic glass capillary with a total length of 11.4 mm, the inner diameter was 170 μm, which corresponds to an aspect ratio of about 67. The capillary was produced in the ATOMKI, Debrecen. The measurements were carried out using HCI beams produced by the 14.5 GHz Electron Cyclotron Resonance Ion Source in Vienna. In this work we investigated the transmission of 4.5 keV Ar9+ ions through the capillary as a function of the tilting angle of the capillary, φ (Fig. 1.) as well as the angular distributions of the transmitted ions. Fig. 1. shows the transmission of ions through the capillary as a function of tilt angle, covering a range of roughly +/- 3 deg. The results strongly support that the guiding effect known from nano-capillaries is also valid up to macroscopic dimensions of the order of mm, so an electric guiding field can also build-up inside a macro-scale single capillary, and thereby slow highly charged ions can be transmitted through the macrocapillary, keeping their initial charge state in a similar manner as for the case of nanocapillaries for tilt angles up to roughly 5 deg. The charging-up of the insulating wall material could be observed in time-dependent transmission measurements
[en] The scientific objective of the S17 payloads was to study the ionosphere during auroral situations and especially with regards to the local fine structure and a possible separation of spatial and temporal variations of auroral phenomena. The intensities of 8 keV and 2 keV electrons have been measured from one sounding rocket launched into a breakup aurora of moderate activity and from another rocket launched into a very active substorm situation. Both the rockets were of mother-daughter type i.e. had two separated payloads. The general features in the data of different particle energies were very similar over the whole flight time of the rockets. Special events and gradients and well identifiable shapes in the particle intensities were studied to see if the intensity fluctuations obtained from two detectors in one payload or from detectors into separate payloads were time delayed. Such time delays in the particle flux intensities were obvious in both of the rocket measurements and most of these time shifts could be understood as caused by spatial variations in the particle precipitation. In parts of the rocket flights the particle intensity variations were true temporal changes. The time lags between 8 keV and 2 keV electron intensities detected in the same payload, which could be observed and were obtained by crosscorrelation analyses, were in the range less than 0.3 s and most of them less than 0.1 s. If the time differences are assumed to be caused by the velocity dispersion of the particles, the particle data reported here placed the modulation source at a distance of less than 10 000 km from the rocket position. Measurements at the S17-1 mother payload of the electric field have been compared with data of precipitating electrons and low-light-level-TV-recording of the auroral situation. An inverted-V precipitation event was observed and was associated with auroral arcs and with reversals of the measured electric field components implicating the possibility of the existence of field-aligned potential drops as an acceleration mechanism for the precipitating auroral particles. (author)
[en] The product of the electronic width of the meson and the branching fractions of its decay to hadrons and electrons has been measured using the KEDR detector at the VEPP-4M collider. The obtained values are The uncertainties shown are statistical and systematic, respectively. Using the result presented and the world-average value of the electronic branching fraction, one obtains the total width of the meson: These results are consistent with the previous experiments.