Search results for "Continuous wave"

Exciton recombination dynamics inInAs∕InPself-assembled quantum wires

2005

In this work we investigate the exciton recombination dynamics in InAs/ InP semiconductor self-assembled quantum wires, by means of continuous wave and time resolved photoluminescence. The continuous wave photoluminescence results seem to indicate that the temperature quenching of the emission band seems to be more probably due to unipolar thermal escape of electrons towards the InP barrier. On the other hand, the analysis of time resolved photoluminescence reveals that the temperature dependence of the radiative and nonradiative recombination times is mainly determined by the dynamics of excitons localized by disorder shigh energy tail of the PL bandd and strongly localized slow energy tai…

Pulsed EPR analysis of tooth enamel samples exposed to UV and gamma-radiations

2011

Abstract The electron paramagnetic resonance (EPR) spectroscopy is widely applied for retrospective dosimetric purposes by means of quantitative detection of radicals in tooth enamel and bone samples. In this work we report a study by cw and pulsed EPR on two samples of human tooth enamel respectively irradiated by UV (254 nm) and γ-exposed. The continuous wave (cw) EPR spectra have shown the usual presence in both samples of two types of CO 2 − radicals, with axial and orthorombic g tensors. We have obtained the electron spin echo detected EPR (ED-EPR) spectra at 80 K of the two samples, and we have shown that they are suitable to mark the difference between the effects produced by the dif…

A combined CWT-DWT method using model-based design simulator for partial discharges online detection

2009

The suppression of noises is fundamental in onsite Partial Discharge (PD) measurements. For this purpose, the wavelet transform analysis method has been developed and it is a powerful tool for processing the transient and suddenly changing signals. As the wavelet transform possesses the properties of multi-scale analysis and time-frequency domain localization, it is also particularly suitable to process the suddenly changing signals of the partial discharge pulse (PD). In this paper, an improved Wavelet denoising method developed by a model-based design software is presented. Simulations are provided as well as some results obtained during laboratory experiment and on-line PD measurements. …

Measurements of Silicon Photomultipliers Responsivity in Continuous Wave

2012

N-on-P and P-on-N Silicon Photomultipliers: Responsivity comparison in the continuous wave regime

2013

We report on the electrical and optical comparison, in continuous wave regime, of two novel classes of silicon photomultipliers fabricated in planar technology on silicon P-type and Ntype substrate respectively. A physical explanation of the experimental results is provided.

Measurements of Silicon Photomultipliers Responsivity

2012

We present some results on the optical characterization of Silicon Photomultipliers designed for medical imaging applications. In particular we will discuss our responsivity measurements performed with very low incident optical power and on a broad spectrum

Measurements of Silicon Photomultipliers Responsivity in Continuous Wave Regime

2013

We report on the electrical and optical characterization, in continuous wave regime, of a novel class of silicon photomultipliers fabricated in standard planar technology on a silicon p-type substrate. Responsivity measurements, performed with an incident optical power down to tenths of picowatts, at different reverse bias voltages and on a broad (340–820 nm) spectrum, will be shown and discussed. The device temperature was monitored, allowing us to give a physical interpretation of the measurements. The obtained results demonstrate that such novel silicon photomultipliers are suitable as sensitive power meters for low photon fluxes.

Locally Supported Wavelets on Manifolds with Applications to the 2D Sphere

1999

Abstract In this paper we present a construction principle for locally supported wavelets on manifolds once a multiresolution analysis is given. The wavelets provide a stable (or unconditional) basis for a scale of Sobolev spaces H s , 0 ≤ s ≤ s . We examine a fast wavelet transform with almost optimal complexity. For the two-dimensional sphere we construct a multiresolution analysis generated by continuous splines that are bilinear with respect to some special spherical grid. In our approach the poles are not exceptional points concerning the approximation power or the stability of the wavelet basis. Finally we present some numerical applications to singularity detection and the analysis o…

Noise decomposition in random telegraph signals using the wavelet transform

2007

Abstract By using the continuous wavelet transform with Haar basis the second-order properties of the wavelet coefficients are derived for the random telegraph signal (RTS) and for the 1 / f noise which is obtained by summation of many RTSs. The correlation structure of the Haar wavelet coefficients for these processes is found. For the wavelet spectrum of the 1 / f noise some characteristics related to the distribution of the relaxation times of the RTS are derived. A statistical test based on the characterization of the time evolution of the scalogram is developed, which allows to detect non-stationarity in the times τ 's which compose the 1 / f process and to identify the time scales of …

Further RF Measurements on the Superconducting 217 MHz CH Demonstrator Cavity for a CW Linac at GSI

2019

Proceedings of the 10th International Particle Accelerator Conference The 10th International Particle Accelerator Conference, Melbourne, Australia, 19 May 2019 - 24 May 2019; Geneva : JACoW Publishing, CERN 2826-2829 (2019). doi:10.18429/JACOW-IPAC2019-WEPRB014