Search results for "Light measurement"
showing 6 items of 6 documents
Improvement of Hall Effect Current Transducer Metrological Performances in the Presence of Harmonic Distortion
2010
The performance of Hall effect current transducers (HECTs), under distorted waveform conditions, is usually characterized by means of a frequency response test. In this paper, it was investigated if frequency response is able to correctly evaluate the ratio and the phase errors under distorted conditions. Two HECTs, with the accuracy class level of 1% and 0.5%, respectively, were experimentally characterized under two conditions: 1) sinusoidal excitation with frequencies ranging from 50 to 750 Hz, which is the well-known frequency response test, and 2) nonsinusoidal excitation using fundamental frequency and one harmonic with adjusted amplitude and phase shift. It was found that ratio and p…
A neutron spectrometer for studying giant resonances with (p, n) reactions in inverse kinematics
2014
A neutron spectrometer, the European Low-Energy Neutron Spectrometer (ELENS), has been constructed to study exotic nuclei in inverse-kinematics experiments. The spectrometer, which consists of plastic scintillator bars, can be operated in the neutron energy range of 100 keV to 10 MeV. The neutron energy is determined using the time-of-flight technique, while the position of the neutron detection is deduced from the time-difference information from photomultipliers attached to both ends of each bar. A novel wrapping method has been developed for the plastic scintillators. The array has a larger than 25% detection efficiency for neutrons of approximately 500 keV in kinetic energy and an angul…
New measurement of the 242Pu(n,γ) cross section at n-TOF-EAR1 for MOX fuels: Preliminary results in the RRR
2016
The spent fuel of current nuclear reactors contains fissile plutonium isotopes that can be combined with 238U to make mixed oxide (MOX) fuel. In this way the Pu from spent fuel is used in a new reactor cycle, contributing to the long-term sustainability of nuclear energy. The use of MOX fuels in thermal and fast reactors requires accurate capture and fission cross sections. For the particular case of 242Pu, the previous neutron capture cross section measurements were made in the 70’s, providing an uncertainty of about 35% in the keV region. In this context, the Nuclear Energy Agency recommends in its “High Priority Request List” and its report WPEC-26 that the capture cross section of 242Pu…
A scintillator based time-of-flight hodoscope with a new type of emitter follower divider
2004
A high precision, time-of-flight hodoscope has been constructed to analyse the secondary pion beam at GSI, Darmstadt. The hodoscope comprises three scintillator planes with the individual scintillator rods read out by photomultipliers in both ends. A new active base of the emitter follower type has been developed for stabilization of voltages at the last dynodes of the photomultiplier. The time resolution of this system was found to be sigma less than or equal to 150 ps for counting rates up to 2 MHz.
High Resolution Time Domain Reflectometry for Dielectric State Monitoring in High Voltage Cables
2017
A high resolution Time Domain Reflectometry system has been designed in order to investigate the possibility of measuring with good accuracy the dielectric properties of high voltage cables insulator materials by means of Time-of-Flight measures. The system employs a dedicated Time-To-Digital Converter in order to achieve a time resolution of 90 ps. By exploiting averaging techniques the resolution has been further increased. Experimental results showed the possibility of measuring the dielectric constant with a resolution of 0.03%.
A Self-powered Ambient Light Power Measurement Platform with Time-domain Readout
2021
Internet of Things (IoT) provides more and more adequate infrastructures for many applications and advanced services. This scenario promotes the ability to satisfy the growing demand for innovative measuring systems, increasingly popular consisting of intelligent nodes, totally wireless, easy to install, and that requires the least possible maintenance. In this context, this paper aims to contribute to state of the art with an energy-autonomous and battery-free measurement platform designed to measure the ambient light power when its level exceeds the sensitivity threshold. The measurement platform utilizes a single transducer to scavenge energy and concurrently measure the ambient light in…