Search results for " Detection"
showing 10 items of 1676 documents
GW190412: Observation of a binary-black-hole coalescence with asymmetric masses
2020
LIGO Scientific Collaboration and Virgo Collaboration: et al.
Precise Measurement of the Neutron Magnetic Form FactorGMnin the Few-GeV2Region
2009
The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q;{2}=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.
The Global-Local Approach for Damage Detection in Composite Structures and Rails
2021
Structural components with waveguide geometry can be probed using guided elastic waves. Analytical solutions are prohibitive in complex geometries, especially in presence of structural discontinuities or defects. The Global-Local (GL) approach provides the solution by splitting the waveguide in “local” and “global” regions. The “local” region contains the part of the structure responsible for the complex scattering of an incident wave. What happens in this region cannot be reproduced analytically. The “global” region is regular and sufficiently far from the scatterer, in order to exploit known analytical wave propagation solutions. The proposed GL approach discretizes the local region by re…
Neutron-induced soft errors in advanced Flash memories
2008
Atmospheric neutrons are a known source of Soft Errors (SE), in static and dynamic CMOS memories. This paper shows for the first time that atmospheric neutrons are able to induce SE in Flash memories as well. Detailed experimental results provide an explanation linking the Floating Gate (FG) cell SE rate to the physics of the neutron-matter interaction. The neutron sensitivity is expected to increase with the number of bits per cell and the reduction of the feature size, but the SE issue is within the limit of current ECC capabilities and will remain so in the foreseeable future.
Toward early-warning detection of gravitational waves from compact binary coalescence
2012
Rapid detection of compact binary coalescence (CBC) with a network of advanced gravitational-wave detectors will offer a unique opportunity for multi-messenger astronomy. Prompt detection alerts for the astronomical community might make it possible to observe the onset of electromagnetic emission from (CBC). We demonstrate a computationally practical filtering strategy that could produce early-warning triggers before gravitational radiation from the final merger has arrived at the detectors.
Small field motion detection in goldfish is red-green color blind and mediated by the M-cone type
2007
Large field motion detection in goldfish, measured in the optomotor response, is based on the L-cone type, and is therefore color-blind (Schaerer & Neumeyer, 1996). In experiments using a two-choice training procedure, we investigated now whether the same holds for the detection of a small moving object (size: 8 mm diameter; velocity: 7 cm/s). In initial experiments, we found that goldfish did not discriminate between a moving and a stationary stimulus, obviously not taking attention to the cue “moving.” Therefore, random dot patterns were used in which the stimulus was visible only when moving. Using black and white random dot patterns with variable contrast between 0.2 and 1, we found…
Recent progress on Frequency Difference Electrical Impedance Tomography
2009
Although time-dierence EIT(tdEIT) has shown promise as a medical EIT imaging tech- nique such as monitoring lung function, static EIT has suered from forward computational model errors including boundary geometry and electrode positions uncertainty combined with the ill-posed and highly nonlinear nature of the corresponding inverse problem. Since 1980s, there has been great endeavor to create forward computational models with the necessary accuracy required for EIT recon- struction, but these eorts were not successful in clinical environment. This is the main reason why we consider frequency-dieren ce EIT (fdEIT) where we take advantage of frequency dependance of biological tissue by inject…
Position-sensitive ion detection in precision Penning trap mass spectrometry
2009
A commercial, position-sensitive ion detector was used for the first time for the time-of-flight ion-cyclotron resonance detection technique in Penning trap mass spectrometry. In this work, the characteristics of the detector and its implementation in a Penning trap mass spectrometer will be presented. In addition, simulations and experimental studies concerning the observation of ions ejected from a Penning trap are described. This will allow for a precise monitoring of the state of ion motion in the trap.
Sub-MeV dark matter and the Goldstone modes of superfluid helium
2019
We show how the relativistic effective field theory for the superfluid phase of helium-4 can replace the standard methods used to compute the production rates of low momentum excitations due to the interaction with an external probe. This is done by studying the scattering problem of a light dark matter particle in the superfluid, and comparing to some existing results. We show that the rate of emission of two phonons, the Goldstone modes of the effective theory, gets strongly suppressed for sub-MeV dark matter particles due to a fine cancellation between two different tree-level diagrams in the limit of small exchanged momenta. This phenomenon is found to be a consequence of the particular…
Characterization of Hong-Ou-Mandel bunched states by quantum homodyne tomography
2014
We experimentally demonstrate quantum homodyne tomography of Hong-Ou-Mandel bunched states, which are created by dynamically adjusting emission timings of two heralded single photons using coupled cavities.