Search results for "Transmission"
showing 10 items of 2080 documents
Monitoring the stability of thin and medium back-up filters of the Newton-XMM EPIC camera
2003
We are conducting a measurement program on back-up filters of the XMM-Newton EPIC camera aimed at monitoring possible aging effects during the mission lifetime. One thin and one medium EPIC back-up filters have been stored since 1997 in an environment similar to that one of the flight filters (dry nitrogen box before launch, high vacuum after launch). The transmission of the two filters has been measured periodically in the 1900-10000 angstrom wavelength range where effects of aging would be clearly evident. The preliminary results, after 5 years of monitoring, show that a slight aging effect has occurred on both filters which, however, has no significant impact onto the EPIC calibration fo…
Unconventional, efficient and flexible bifocal lens design by metalens and AFA beam combination
2019
In the field of metasurface-based light focusing, both convex metalenses with parabolic phase profile and autofocused Airy (AFA) beams play essential roles. AFA beam generation as a combination of two convergent mirrored Airy beams leaves the space between the two launched Airy profiles inefficient with zero amplitude transmission and constant phase distribution. In this paper, we propose using this inutile space as an independent metalens. We show that coincidence of the focal spot of the metalens to that of the AFA beam will increase the focusing intensity more than 24 percent at its focal point. It is shown that using the nonoperative space between the two launched Airy beams as an indep…
Dispersion-managed electrical transmission lines
2009
International audience; We examine the ability of electrical pulses to execute a highly stable propagation in a special electrical network made of concatenated pieces of discrete electrical lines with alternately positive and negative signs of the second-order dispersion. We show that such networks, called dispersion-managed electrical lines, induce a pulse breathing phenomenon, that is a dynamical behaviour with alternate regimes of pulse broadening and compression. This breathing phenomenon, which prevents the pulse from broadening without bounds during propagation in the network is the most appealing feature of the technique of dispersion management developed in the last decade in the ar…
Bright and dark optical solitons in fiber media with higher-order effects
2002
We consider N-coupled higher-order nonlinear Schrodinger (N-CHNLS) equations which govern the simultaneous propagation of N optical fields in fiber media with higher-order effects. Bright and dark soliton solutions are derived using Hirota bilinear method for the general cross-coupling ratio between the parameters of self-phase modulation and cross-phase modulation effects. By means of coupled amplitude-phase formulation also, similar kind of dark soliton solutions are obtained. It is found that the parametric conditions for the simultaneous propagation of N dark solitons from both the methods are the same.
Existence results for a nonlinear nonautonomous transmission problem via domain perturbation
2021
In this paper we study the existence and the analytic dependence upon domain perturbation of the solutions of a nonlinear nonautonomous transmission problem for the Laplace equation. The problem is defined in a pair of sets consisting of a perforated domain and an inclusion whose shape is determined by a suitable diffeomorphism $\phi$. First we analyse the case in which the inclusion is a fixed domain. Then we will perturb the inclusion and study the arising boundary value problem and the dependence of a specific family of solutions upon the perturbation parameter $\phi$.
Übertragungseigenschaften eines handelsüblichen Oscillographen zur Herzschallregistrierung
1967
Phonokardiogramme geben nur insofern den Herzschall wieder, als die Einflusse der Mesapparatur eliminiert sind. Eine amplituden- und phasentreue Darstellung des Herzschalls ist nicht moglich, wenn man auch dessen oberes Spektrum auswertbar registrieren will. Dadurch werden Filter notig, die das Eingangssignal erheblich linear verformen. Die vorliegende Arbeit beschreibt Amplituden- und Phasengang einer Mesapparatur, bestehend aus Phonokardiograph (Atlas 6/6) und Registrieroscillograph (CEC-Galvomat 5-124), so das mit Hilfe der gemessenen Kurven die lineare Verformung ersichtlich und eliminierbar wird. Dadurch wird es moglich, die Ergebnisse mathematischer Frequenzanalysen von Phonokardiogra…
Peculiarities of imaging one- and two-dimensional structures using an electron microscope in the mirror operation mode.
2001
Measurements performed in an electron microscope with the mirror operation mode are most sensitive to local electric fields and geometrical roughness of any kind of the object being studied. The object with a geometrical relief is equivalent to a smooth surface with an effective distribution of microfields. Electrons forming the image interact with the local microfields for an extended time: during approach to the object, deceleration and acceleration away from the object. As a result, the electron trajectories can be strongly distorted, and the contrast changes essentially, leading to image deformation of details of the object under investigation and to lowering of the resolution. These ef…
Determination of IBIS mask transmission matrix
2005
The high-angular resolution imager IBIS is one of the two main instruments aboard the ESA INTEGRAL satellite launched in October 2002. IBIS uses coded aperture mask technique in order to provide the required imaging capabilities for energies between 15 and 10 MeV.The precise knowledge of the coded mask response function critically determine the IBIS imaging performances. In this paper, we present a general description of the IBIS coded mask design together with its main features. Transparency and homogeneity values of the IBIS mask flight model from our laboratory measurements are presented with indication of the instrumental set-up used and accuracy achieved. Mask transmission as a functio…
The Topological Processor for the future ATLAS Level-1 Trigger: From design to commissioning
2014
The ATLAS detector at the Large Hadron Collider (LHC) is designed to measure decay properties of high energetic particles produced in the proton-proton collisions. During its first run, the LHC collided proton bunches at a frequency of 20 MHz, and therefore the detector required a Trigger system to efficiently select events down to a manageable event storage rate of about 400 Hz. By 2015 the LHC instantaneous luminosity will be increased up to 3×1034cm−2s−1: this represents an unprecedented challenge faced by the ATLAS Trigger system. To cope with the higher event rate and efficiently select relevant events from a physics point of view, a new element will be included in the Level-1 Trigger …
Comment on "Dynamics and properties of waves in a modified Noguchi electrical transmission line"
2016
A recent paper [Phys. Rev. E 91, 022925 (2015)PRESCM1539-375510.1103/PhysRevE.91.022925] presents the derivation of the nonlinear equation modeling envelope waves in a specific case of band passed filter discrete nonlinear electrical transmission line (NLTL), called "A modified Noguchi electrical transmission line" according to the authors. Using the reductive perturbation approach in the semidiscrete approximation, they showed that the modulated waves propagating in this NLTL are described by the ordinary nonlinear Schrodinger (NLS) equation. On the basis of their results, the authors claimed that all previous works on the band passed filter NLTL, which considered the vanishing of the dc c…