Scintillation

About: Scintillation is a research topic. Over the lifetime, 14022 publications have been published within this topic receiving 187694 citations.

The MU-RAY experiment. An application of SiPM technology to the understanding of volcanic phenomena

Abstract: The purpose of the MU-RAY project is to develop an innovative approach to the study of volcanoes and their monitoring based on a particle physics approach. The test site is Vesuvio: one of the higher risk volcanoes in the world. In this context, muon radiography is an innovative method of enormous impact. This is an imaging technique which relies on the measurement, by means of a cosmic ray telescope, of the absorption in the volcano of muons with near-horizontal trajectories, produced by the interactions of cosmic rays with the atmosphere. Since 2003 this technique has been successfully used on volcanoes in Japan, providing pictures of their vertices with resolutions much better than those obtained with the traditional techniques based on gravimeters. Researchers from Naples and Florence are currently involved in the construction and testing of a prototype telescope based on the use of bars of plastic scintillator with a triangular section whose scintillation light is collected by special fibres (wave length shifters) and transported to SiPM (Silicon photomultipliers). A complete prototype telescope, consisting of three xy scintillation planes and 1 m2 active area has been assembled and is now under test.

Asymmetric signal level distribution due to tropospheric scintillation

Abstract: Short term distribution of signal fluctuations due to troposheric scintillation (in decibels) is usually modelled as Gaussian. For long term distribution, this results in a symmetrical distribution function. However, various experiments have shown a significant asymmetry in long term distribution for strong scintillations. It is shown that the observed asymmetry follows directly from theory, if a different modelling approach is applied.

Scintillator for Thermal Neutrons using Li6F and ZnS (Ag)

Abstract: A description is given of the characteristics of a Li6 ZnS scintillator which has a detection efficiency for a thermal spectrum of neutrons one and one-half times that of the best available scintillator based on Bi10 and ZnS, and almost three times that of commercially available B10 -ZnS scintillators. The detection efficiency of the Li6 -ZnS scintillator was determined by comparison with a BF3 counter in a beam of monokinetic neutrons. The scintillator is insensitive to gamma rays, although a counter assembly consisting of a large light guide of Lucite as well as the scintillator and a photomultiplier does respond to gamma rays at low bias settings.

Forecasting low-latitude radio scintillation with 3-D ionospheric plume models: 2. Scintillation calculation

Abstract: [1] A three-dimensional model has been developed for the plasma plumes caused by interchange instabilities in the low-latitude ionosphere to describe the structure and extent of the radio scintillation generated by turbulence around and within the plumes. With the inclusion of the processes that determine the transport of plasma parallel to the geomagnetic field lines as well as transverse to them, the model can predict the extent in latitude of the plumes and their scintillation. Diagnostics presented here include illustrations of the spectral density of the density irregularities that develop within the plumes. An extrapolation of the density irregularity spectrum down into the wavelength regime effective for radio wave scattering permits a phase screen calculation of the amplitude scintillation caused by the plumes. The scintillation produced by the model has much the same character as measurements of scintillation do in terms of the time and rate of onset of scintillation, duration, and latitudinal extent.