Sull’interpretazione di alcuni eventi sismici particolari registrati dalla Rete Sismica Nazionale Centralizzata

Il presente lavoro costituisce un contributo nel campo dell’interpretazione e del riconoscimento delle forme d’onda generate durante un evento sismico sia di origine naturale sia artificiale. In esso vengono descritti una serie di fenomeni particolari studiati nel corso degli anni da parte del gruppo di analisti che si occupa dell’interpretazione dei dati sismici registrati dalla Rete Sismica Nazionale Centralizzata (RSNC) dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV). Vengono, inoltre, presentati alcuni eventi “contemporanei” locali nonché alcuni casi di eventi locali “contemporanei” ad eventi regionali o telesismici. Successivamente sono illustrati alcuni esempi di eventi sismici “caratteristici” sia di origine naturale (terremoti profondi, eruzioni vulcaniche, terremoti di origine vulcanica e frane) sia di origine artificiale (esplosioni). La presente pubblicazione, oltre ad avere un carattere divulgativo riguardante le esperienze maturate negli ultimi anni dal gruppo di lavoro, ha anche lo scopo di mettere in evidenza alcune peculiarità della sismicità presente nel territorio italiano

Scintillating double beta decay bolometers

We present the results obtained in the development of scintillating Double Beta Decay bolometers. Several Mo and Cd based crystals were tested with the bolometric technique. The scintillation light was measured through a second independent bolometer. A 140 g CdWO_4 crystal was run in a 417 h live time measurement. Thanks to the scintillation light, the alpha background is easily discriminated resulting in zero counts above the 2615 keV gamma line of Thallium 208. These results, combined with an extremely easy light detector operation, represent the first tangible proof demonstrating the feasibility of this kind of technique.Comment: 15 pages, 8 figure

Spin-wave propagation in a microstructured magnonic crystal

Transmission of microwave spin waves through a microstructured magnonic crystal in the form of a permalloy waveguide of a periodically varying width was studied experimentally and theoretically. The spin wave characteristics were measured by spatially-resolved Brillouin light scattering microscopy. A rejection frequency band was clearly observed. The band gap frequency was controlled by the applied magnetic field. The measured spin-wave intensity as a function of frequency and propagation distance is in good agreement with a model calculation.Comment: 4 pages, 3 figure

Optical issues for the diagnostic stations for the ELI-NP compton gamma source

A high brightness electron Linac is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32 bunches, 16 ns spaced, with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with optical transition radiation (OTR) profile monitors. In order to measure the beam properties, the optical radiation detecting system must have the necessary accuracy and resolution. This paper deals with the studies of different optic configurations to achieve the magnification, resolution and accuracy in order to measure very small beam (below 30 μm) or to study the angular distribution of the OTR and therefore the energy of the beam. Several configurations of the optical detection line will be studied both with simulation tools (e.g. Zemax) and experimentally. The paper will deal also with the sensibility of optic system (in terms of depth of field, magnification and resolution) to systematic error