Search results for "LIGHT"
showing 10 items of 3575 documents
Fast Response Vibration Sensor Based on Bragg Gratings Written on Tapered Core Fibers
2006
Bragg gratings written in tapered core fibers are used to measure mechanical vibrations with a time response better than 10 μs. The system is compact, low-cost and can be wavelength multiplexed.
White light supercontinuum generation in a Y-shaped microstructured tapered fiber pumped at 1064 nm.
2010
We report the generation of supercontinuum in a Ge-doped Y-shape tapered fiber pumped at 1064 nm in the ns pump regime. The taper was designed to have long taper transitions and a taper waist with a core diameter of 0.9 mum. The large air-filling fraction and diameter of the air-hole microstructure reduces the confinement loss at long wavelengths so, enabling the extension of the spectrum to longer wavelengths. Along the taper transition the zero-dispersion wavelength decreases as the diameter of the taper becomes smaller. The spectral components generated along the taper transition pump the taper waist, enhancing the generation of short wavelengths. A flat spectrum spanning from 420 nm to …
Global Frequency and Geographical Distribution of Nighttime Streamer Corona Discharges (BLUEs) in Thunderclouds
2021
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
Correlation between relative sunshine and state of the sky
1981
Abstract It is possible to construct a sunshine map referring to a large zone, lacking in a widespread network of recording stations, correlating the relative sunshine with the “state of the sky”, defined by the monthly mean number of the clear, mixed and overcast days, whose data are more largely available. In the correlation here proposed climatological and meteorological factors are introduced in order to express the helioclimatic characteristics of every location. The application to Italy, using the data of the period 1973–1977 provided by the 31 stations of ITAV, has suggested the classification of these stations in seven “helioclimatic groups” characterized by different values of the …
Scheduling in Targeted Transient Surveys and a New Telescope for CHASE
2010
We present a method for scheduling observations in small field-of-view transient targeted surveys. The method is based on maximizing the probability of detection of transient events of a given type and age since occurrence; it requires knowledge of the time since the last observation for every observed field, the expected light curve of the event, and the expected rate of events in the fields where the search is performed. In order to test this scheduling strategy we use a modified version of the genetic scheduler developed for the telescope control system RTS2. In particular, we present example schedules designed for a future 50 cm telescope that will expand the capabilities of the CHASE s…
A search for light dark matter in XENON10 data
2011
We report results of a search for light (3.5x10^{-42} cm^2, for a dark matter particle mass m_{\chi}=8 GeV. We find that our data strongly constrain recent elastic dark matter interpretations of excess low-energy events observed by CoGeNT and CRESST-II, as well as the DAMA annual modulation signal.
Transition from self tilt to object tilt during maintained lateral tilt in parabolic flight.
1991
Abstract 19 young healthy subjects were subjected to parabolic rollercoaster flight. A horizontal luminous line was seen by the subjects in a headfixed goggle device. During the hypergravic phases of parabolic flight the luminous line seemed to rotate into and during the hypogravic phase against the direction of static head tilt. Ocular counter rotation and activity of the neck position receptors cannot explain these subjective rotations. We conclude that information from the otolith system, converging with visual information within the brain, dislocated the headfixed visual target line. While the retinal image of the luminous line remains unchanged, loading and unloading the otoliths in pa…
Relativism and radical conservatism
2019
The chapter tackles the complex, tension-ridden, and often paradoxical relationship between relativism and conservatism. We focus particularly on radical conservatism, an early twentieth-century German movement that arguably constitutes the climax of conservatism’s problematic relationship with relativism. We trace the shared genealogy of conservatism and historicism in nineteenth-century Counter-Enlightenment thought and interpret radical conservatism’s ambivalent relation to relativism as reflecting this heritage. Emphasizing national particularity, historical uniqueness, and global political plurality, Carl Schmitt and Hans Freyer moved in the tradition of historicism, stopping short of …
Nuclear Spin Relaxation in Viscous Liquids: Relaxation Stretching of Single-Particle Probes
2021
Spin-lattice relaxation rates R1(ω,T), probed via high-field and field-cycling nuclear magnetic resonance (NMR), are used to test the validity of frequency-temperature superposition (FTS) for the reorientation dynamics in viscous liquids. For several liquids, FTS is found to apply so that master curves can be generated. The susceptibility spectra are highly similar to those obtained from depolarized light scattering (DLS) and reveal an excess wing. Where FTS works, two approaches are suggested to access the susceptibility: (i) a plot of deuteron R1(T) vs the spin-spin relaxation rate R2(T) and (ii) a plot of R1(T) vs an independently measured reference time τref(T). Using single-frequency s…
Coupling evanescently low loss Silicon-on-insulator ridge waveguides including high Q nanocavities for light control
2011
Summary form only given. In this work, we propose an innovative way to achieve an air-slotted nanocavities by coupling evanescently low loss Silicon-on-insulator (SOI) ridge waveguides(WGs) including high Q nanocavities exhibiting an ultrasmall modal volume V. We first show that coupling two WGs allows us to achieve a field confinement within the air slot as low as lambda/30 while preserving a high group index of the guided modes. Then we demonstrate that merging such coupled WGs with state-of-the-art high-Q/small V nanocavities is a robust way to achieve a single compact (1 µm × 3 µm) air-slotted resonator on substrate. Finally, we extend the concept to multiple air-slotted resonator syste…