A.C. Quantum interference in superconducting films with periodically modulated thickness

a.c. quantum interference has been observed in type II superconducting films with periodic thickness modulation. Marked supercurrent steps appear at well defined voltages in the current-voltage characteristics when vortex motion is induced by superimposed d.c. and r.f. currents. An essential condition for the observation of the effect is matching of the vortex lattice to the periodic pinning structure due to the thickness modulation.     

Phase and vortex dynamics in Josephson junction arrays with percolative disorder

The AC conductance G of site-diluted Josephson junction arrays close to the percolation threshold was studied over a broad frequency range. As a function of frequency, G exhibits a crossover from a low-frequency Euclidean to a high-frequency fractal regime. At low-frequency the response is dominated by vortices and its temperature dependence is well-described by dynamical extensions of the Kosterlitz–Thouless theory for two-dimensional systems.     

Workshop on Timing Modes for Low-Emittance Storage Rings

A three-day workshop was held in Lund, Sweden, from March 25 to 27, 2015, with a focus on timing modes for low-emittance storage rings. The MAX IV Laboratory, currently under construction in Lund, will provide a 1.5 GeV storage ring for soft X-rays and a 3 GeV storage ring with an ultralow emittance down to 0.2 nm rad for hard X-rays [1 M. Eriksson, Proceedings of 2011 PAC, TUOBS4, 737–741 (2011). [Google Scholar]]. Both rings are designed to operate with a uniform multibunch filling pattern with a 100 MHz RF system and employ passive harmonic cavities [2 Å. Andersson, Proceedings of IPAC 2011, MOPC051, 193–195 (2011). [Google Scholar]] to damp instabilities and increase the Touschek lifetime. For the 3 GeV ring, the harmonic cavities are also required to conserve the ultralow emittance at high bunch charge [3 S. C. Leemann, Phys. Rev. ST Accel. Beams 17, 050705 (2014).[Crossref] , [Google Scholar]]. The facility will include a short pulse facility delivering 100 fs FWHM X-ray pulses at a repetition rate of 100 Hz.     

The\overrightarrow p - Si elastic scattering in the region of giant multipole resonances

Analyzing powers and cross sections for the scattering of polarized protons from Si have been measured at eight energies between 17 and 29MeV. The analysing powers show an “anomalous” behaviour and an optical model analysis yields a non-monotonic effect in the spin-orbit potential.     

Polarization in n-d scattering at 14.2 MeV

The angular distribution of the analyzing power in ${}^2\text{H(}\text{n}\text{,}\text{n}{}^2\text{H}$ elastic scattering has been measured at a neutron energy of 14.2 MeV in the angular range 50° to 152° c.m. Neutrons with a polarization of approximately 0.5 were obtained from the ${}^3\text{H(}\text{d}\text{n}\text{)}{}^4\text{He}$ reaction at a deuteron energy of 140 keV and lab emission angle of 82°. The ${}^3\text{H(}\text{d}\text{n}\text{)}{}^4\text{He}$ reaction was induced by vector polarized douterons obtained from a source of polarized ions. The latter was of a conventional “atomic beam” type. The results show good agreement with the data on the charge symmetric $\text{p}\text{+}\text{d}$ process at a proton energy of 14.5 MeV. Comparison is also made with the theoretical calculations of Doleschall and of Pieper and a good agreement is found.     

Quantitative, spektrophotometrische Bestimmung von Apoatropin neben Atropin

Ohne Zusammenfassung