Search results for "Electromagnetisme Mesuraments"
showing 9 items of 9 documents
Experimental demonstration of the physics of resonant cavities
2005
We describe an undergraduate experiment that demonstrates the physics of cavity resonators. A mobile wall lets students alter the position of the nodes, thus changing the mode pattern. The nodal structure is made apparent by placing a metallic plate at different positions inside the cavity. A technique for dielectric characterization also is introduced, which helps students understand the boundary conditions in dielectrics, as well as highlighting the characteristics of fields in cavities.
Measurement of lifetimes in Fe-62,Fe-64, Co-61,Co-63, and Mn-59
2017
Lifetimes of the 4(1)(+) states in Fe-62,Fe-64 and the 11/2(1)(-) states in Co-61,Co-63 and Mn-59 were measured at the Grand Accelerateur National d'Ions Lourds (GANIL) facility by using the Advanced Gamma Tracking Array (AGATA) and the large-acceptance variable mode spectrometer (VAMOS++). The states were populated through multinucleon transfer reactions with a U-238 beam impinging on a Ni-64 target, and lifetimes in the picosecond range were measured by using the recoil distance Doppler shift method. The data show an increase of collectivity in the iron isotopes approaching N = 40. The reduction of the subshell gap between the nu 2p(1/2) and nu 1g(9/2) orbitals leads to an increased popul…
D-0-(D-0)over-bar mixing in the weak-gauged U(4)(L)circle times U(4)(R) chiral Lagrangian model
1998
The D-0- mixing is analyzed in a weak gauged U(4)(L) x U(4)(R) chiral lagrangian model where the electroweak interaction is introduced as a gauge theory over the meson degrees of freedom. This model allows a particular realization of the G.I.M. mechanism and then could be useful in the study of processes where G.I.M. suppression is effective. As a test of the model we have also analyzed the K-0- mixing. We find am, in good agreement with the experimental result and we show that the D-0- mixing is very much suppressed in agreement with previous estimates in the Heavy Quark expansion framework.
Design and Study of a Wide-Band Printed Circuit Board Near-Field Probe
2021
Magnetic near-field probes (NFP) represent a suitable tool to measure the magnetic field level from a small electromagnetic interference (EMI) source. This kind of antenna is useful as a magnetic field probe for pre-compliance EMC measurements or debugging tasks since the user can scan a printed circuit board (PCB) looking for locations with strong magnetic fields. When a strong H-field point is found, the designer should check the PCB layout and components placement in that area to detect if this could result in an EMI source. This contribution focuses on analyzing the performance of an easy to build and low-cost H-field NFP designed and manufactured using a standard PCB stack-up. Thereby,…
Resonancias de ondas electromagnéticas
1994
Este artículo describe un conjunto de experimentos diseñados para medir las resonancias electromagnéticas de varios sistemas sencillos.
FILTER RESPONSE OF RESONANT WAVEGUIDE DIELECTRIC GRATINGS AT PLANE-WAVE CONICAL INCIDENCE
2009
An accurate and efficient formulation is presented for the electromagnetic analysis of dielectric waveguide gratings under plane-wave conical incidence. An arbitrary number of dielectric bars can be placed inside each one-dimension periodic cell, including the effect of dielectric losses. The reflectance of a dielectric waveguide grating under conical incidence is compared with theoretical results presented by other authors, finding a very good agreement. A single-layer reflection filter has been designed centered at λ0=1.5 μm whose spectral and angular responses are shown. For this structure, the effect of the asymmetry of the distribution of the refraction index in the reflectance has bee…
Subjective symptoms related to GSM radiation from mobile phone base stations : a cross-sectional study
2013
Objectives: We performed a reanalysis of the data from Navarro et al., 2003, in which health symptoms related to microwave exposure from mobile phone base stations (BS) were explored, including data obtained in a retrospective inquiry about fear of exposure from BS. Design: Cross-sectional study. Setting: La Ñora (Murcia), Spain. Participants: Participants with known illness in 2003 were subsequently disregarded: 88 participants instead of 101 (in 2003) were analysed. Since weather circumstances can influence exposure, we restricted data to measurements made under similar weather conditions. Outcomes and methods: A statistical method indifferent to the assumption of normality was employed: …
Model independent bounds on the tau lepton electromagnetic and weak magnetic moments
2000
Using LEP1, SLD and LEP2 data, for tau lepton production, and data from CDF, D0 and LEP2, for W decays into tau leptons, we set model independent limits on non-standard electromagnetic and weak magnetic moments of the tau lepton. The most general effective Lagrangian giving rise to tau moments is used without further assumptions. Precise bounds ($2\sigma$) on the non-standard model contributions to tau electromagnetic ($-0.007<a_\gamma< 0.005$), tau Z-magnetic ($-0.0024 <a_Z< 0.0025$) and tau W-magnetic ($-0.003 < \kappa^W < 0.004$) dipole moments are set from the analysis.
A New Approach to the Modeling of Anisotropic Media with the Transmission Line Matrix Method
2021
A reformulation of the Transmission Line Matrix (TLM) method is presented to model non-dispersive anisotropic media. Two TLM-based solutions to solve this problem can already be found in the literature, each one with an interesting feature. One can be considered a more conceptual approach, close to the TLM fundamentals, which identifies each TLM in Maxwell’s equations with a specific line. But this simplicity is achieved at the expense of an increase in the memory storage requirements of a general situation. The second existing solution is a more powerful and general formulation that avoids this increase in memory storage. However, it is based on signal processing techniques and considerabl…