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171.
The ratio of the electric and magnetic proton form factors,G
Ep
G
Mp
, has been obtained in two Hall A experiments, from measurements of the longitudinal and transverse polarizations of the recoil
proton,P
l
andP
t
, in the elastic scattering of polarized electrons,
. Together these experiments cover theQ
2
range of 0.5 to 5.6 GeV2. A new experiment is currently being prepared, to extend theQ
2
range to 9 GeV2 in Hall C. 相似文献
172.
基于广义变分原理和约束系统的变换性质,说明了电磁波在介质分界面上反射和折射时能量中心的横移效应的存在性.纠正了文[10]中出现的错误。 相似文献
173.
Two-dimensional relativistic electromagnetic dromion-like soliton in a cold transparent plasma 下载免费PDF全文
By using a standard multiple scale method, a Davey--Stewartson (DS) equation
has been derived and also applied to a multi-dimensional analytical
investigation on the interaction of an ultra-intense laser pulse with a cold
unmagnetized transparent electron-ion plasma. The regions of instability are
found by considering the modulation instability of a plane wave solution of
the DS equation. The DS equation is just of the Davey--Stewartson 1 (DS1) type
and admits a dromion solution, i.e. a two-dimensional (2D) dromion soliton
decaying exponentially in all spatial directions. A 2D relativistic
electromagnetic dromion-like soliton (2D REDLS) is derived for a vector
potential. 相似文献
174.
175.
基于耦合场量子受激拉曼散射的太赫兹波辐射 总被引:2,自引:3,他引:2
使用两块长度各为65 mm的MgO:LiNbO3和无掺杂LiNbO3晶体,以1064nm的Q开关Nd:YAG激光器作为抽运光源,在12 mJ/pulse的抽运光能量下得到频率范围为0.34~2.90 THz的电磁辐射.分析表明,激光入射使LiNbO3晶体中具有电磁特性的横光学声子可以和入射光子形成耦合场量子.作为一种电磁特性的元激发,LINbO3晶体的耦合场量子的辐射场频率覆盖部分太赫兹频段范围,并可通过耦合场量子受激拉曼散射过程辐射THz波.根据耦合场量子辐射理论,通过分析晶体的耦合场量子色散特性曲线,可以确定该晶体能否辐射THz波及其带宽范围. 相似文献
176.
In a capillary discharge experiment for the neon-like argon lasing, we have proposed an experimental scheme to verify that the multi-spike of X-ray diode (XRD) signal is a multi-pulse laser or is a reflection of the laser pulse in the XRD.The ceramic capillary has an inner diameter of 3mm and a length of 200mm.At the gas pressure of 28Pa and discharge current of 27kA, stable lasing has been realized.The experimental results prove that the multi-spike of XRD signal is a reflection of the electromagnetic signal produced by the laser pulse in the XRD.The improved electrocircuit scheme of the XRD to minimize the reflection phenomena is also found. 相似文献
177.
本文主要介绍了电饭锅、微波炉和电磁灶3种家用加热电器的工作原理,旨在教学中将理论知识与实际生活相结合,有助于加深对知识的理解,也激发了学生们的兴趣和求知欲. 相似文献
178.
Based on the orthogonalities of the vector wave functions, the expressions of scattering fields are developed as the particle in the zero order field and in the first order fields of x, y, and z, respectively. A general relation between the expansion coefficients of scattering field and incident field is presented. Taking the elliptical beam for example, the scattering property of a particle in beam is investigated. After analyzing the effects of the beam waist, irradiating distance, etc. on scattering property, the validity of the proposed algorithm is demonstrated. Results show that the beam waist may improve the particle identification property and the particle has a strong scattering both in the forward direction and in the backward direction. The method proposed is simple and is a new way of researching the scattering from particles in electromagnetic beams. 相似文献
179.
一个关于勒让德多项式的积分公式及其简单应用——圆形带电环和电流环的静态电磁势 总被引:1,自引:0,他引:1
给出了一个关于勒让德多项式的积分公式及其证明,用该公式和叠加法方便快捷地导出了圆形带电环和电流环的静态电磁势. 相似文献
180.
The Neighbor Cell Deposited Energy Ratio (NCDER) is a new method that is proposed to reconstruct incidence position in a single layer for a 3-dimensional imaging electromagnetic calorimeter (ECAL). This method was applied to reconstruct the ECAL test beam data for the Alpha Magnetic Spectrometer-02 (AMS-02). The results show that this method can achieve an angular resolution of 7.36±0.08°/√E+0.28±0.02° in the determination of the photon's direction, which is much more precise than that obtained with the commonly-adopted Center of Gravity (COG) method (8.4±0.1°/E+0.8±0.3°). Furthermore, since it uses only the properties of electromagnetic showers, this new method could also be used for other type of fine grain sampling calorimeters. 相似文献