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[en] The measured K-shell fluorescence yield values that were reported in the literature from 1994 to 2011 were reviewed and presented in a table form (about 341 new measurements). The Weighted-mean values of experimental data were fitted by the analytical function to deduce new empirical K-shell fluorescence yields for a broad range of elements. The results were compared with the other theoretical, experimental and semi-empirical values reported in the literature. Reasonable agreement was typically obtained between our result and other works. - Highlights: ► The updated database relies on the different publications from 1994 till 2011. ► The results were presented for elements from (11Na) to (99Es). ► The experimental data are fitted to deduce the empirical fluorescence yields.
[en] In this paper, we present an extension of large network visualization (LaNet-vi), a tool to visualize large scale networks using the k-core decomposition. One of the new features is how vertices compute their angular position. While in the later version it is done using shell clusters, in this version we use the angular coordinate of vertices in higher k-shells, and arrange the highest shell according to a cliques decomposition. The time complexity goes from O(n√n) to O(n) upon bounds on a heavy-tailed degree distribution. The tool also performs a k-core-connectivity analysis, highlighting vertices that are not k-connected; e.g. this property is useful to measure robustness or quality of service (QoS) capabilities in communication networks. Finally, the actual version of LaNet-vi can draw labels and all the edges using transparencies, yielding an accurate visualization. Based on the obtained figure, it is possible to distinguish different sources and types of complex networks at a glance, in a sort of 'network iris-print'.
[en] In this study, empirical K-shell fluorescence yields (ωK) from the available experimental data for elements with 6≤Z≤99 were calculated. The experimental data are fitted using the quantity (ωK/(1-ωK))1/q (where q=3, 3.5 and 4) vs. Z to deduce the empirical fluorescence yields. A comparison is made between the results of the procedures followed here and the literature theoretical and empirical values.
[en] The technique used in the experiment in the search for the process of 2K2ν-capture in 124Xe using large high-pressure proportional counters is briefly described. The measurements with a xenon sample enriched to 21% (or ~57 g) of the 124Xe isotope carried out for 3340 hours yielded a zero signal. The resultant upper limit on the 124Xe half-life with respect to the 2ν-mode of the nuclear capture of two K-shell electrons amounts to T1/2>4.6 1021 yr at the 90% confidence level.
[en] We have recently studied the threshold behavior of the K-shell photoelectron satellite/main line branching ratios in CO with high-resolution photoelectron spectroscopy and zero electron kinetic energy (ZEKE) spectroscopy. The electron time-of-flight measurements were performed at the Stanford Synchrotron Radiation Laboratory with a spherical grating monochromator. The ZEKE spectra above the Cls and Ols ionization thresholds show remarkable differences in the shake-up energy and intensity distribution of similar 1s-1π- 1π satellite states. The energy dependency of the branching ratios of eight Cls satellite states will be presented. In the region of the triplet coupled Cls-1π-1π satellite around 305 eV, we were able to resolve three components that show a variation in the branching ratios as a function of the photon energy
[en] In this work, measurements were made of the incoherent Compton effect of high energy photons on K - electrons of heavy elements. The experimental arrangement consisted of a 137CS source emitting 662 KeV photons in a lead target scattered at 1230. (A.C.A.S.)
[pt]Foram feitas medidas de espalhamento Compton (incoerente) de fotons com alta energia em eletrons K de elementos pesados. O arranjo experimental utilizado consiste numa fonte de 137Cs que emite fotons de 662 KeV num alvo de chumbo sendo estes espalhados a 1230. (A.C.A.S.)
[en] Having laser intensities of 1021 W/cm2 yield electrical field strengths of 1012 V/cm which is comparable to the field strength at the K-shell of neon. Instant field ionization becomes part of the laser-matter interaction allowing to transfer most of the photons momenta directly onto the ions by driving an electrostatic shock through the target equivalent to pressures of several 100 Gbar. Utilization of these high-pressure conditions in form of equation of state measurements, however, strongly depends on the contrast of the femtosecond laser pulse. Currently, the Livermore USP and JanUSP lasers reach contrast values up to 108. This is sufficient to explore near-isochorically heated materials at moderate intensities (1013-1015 W/cm2) attaining pressures around 100 Mbar