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981.
冯贤平 《核聚变与等离子体物理》1988,(2)
本文在临界密度区域内激光场趋于零的假设下,系统地研究了由强激光辐照非均匀等离子体引起临界密度变陡的现象,给出了较为精确、完备的描述等离子体密度结构的各种参数和等离子体密度的坪台结构。 相似文献
982.
A very important question in ultrarelativistic heavy ion collisions is that of thermalization of the high energy density quark
gluon plasma forud in the central rapidity region. Different approaches have been adopted by various authors to study this
thermalization problem. These include phenomenological string and capacitor plate models, perturbative QCD based parton cascade
models and the classical non-perturbative approach. In this paper we briefly review the earlier studies and discuss our work
which emphasizes the role of non-perturbative collective effects (classical chaos) in the thermalization of the plasma. In
particular, using classical equations of motion of a coloured parton in self-consistent colour fields, we have carried out
a 1+1 dimensional simulation of coloured partonic matter. We find that in certain parameter domains, the system exhibits chaotic
behaviour in non-abelian plasma oscillations, which then leads to thermalization of the plasma. 相似文献
983.
Jianqiang Wu Caidong Xiong Shenggang Liu 《International Journal of Infrared and Millimeter Waves》1995,16(8):1317-1328
The effect of three-dimensional perturbed velocity and three-dimensional perturbed current density on the beam-wave interaction of dielectric Cherenkov maser is analysed by use of the self-consistent linear field theory. Three distinct cases are considered. First, the propagation of the electron beam in an annular dielectric liner enclosed by a loss-free conducting wall is investigated. The dispersion equation and the simultaneous condition of the beam-wave interaction are derived. It's clearly shown that the instability of the interaction results from the coupling of the TM mode in the dielectric lined slow-wave waveguide to the beam mode via the electron beam. And the coupling is proportional to the density of the beam. The growth rate of the wave produced by the electron beam are obtained. Then, the case of a relativistic electron beam guided by a longitudinal magnetic field in the same slow-wave structure is examined. The motion of electrons could be approximated to be one-dimensional when the simultaneous condition of the beam-wave interaction of dielectric Cherenkov maser is satisfied. Finally, the effect of the background plasma on the instability of the beam-wave interaction is studied.This work is supported by National Natural Science Foundation of China. 相似文献
984.
在激光等离子体实验研究中,为了更好地了解激光与等离子体相互作用过程中所发生的物理过程,要求能够高时间分辨地观测等离子体所辐射的X射线的特征。测量的关键在于X射线探测元件,既要有快的时间响应,又要能够输出足够大的光电流,以便直接驱动高速示波器,进行显示和照像。普通的闪烁体/光电倍增管X射线探测器,由于闪烁体荧光有着固有的衰减时间,以及普通的光电倍增管中的电子飞行时间离散严重,时间分辨力难以提高。 相似文献
985.
The neutral particle recycling models that have been used to date in numerical plasma confinement simulations are by no means
equivalent but may lead, instead, to divergent results. As a consequence of this confinement studies based on individual neutral
assumptions must be received with a healthy degree of scepticism.
We go on to compare experimental observations of the time development of plasma density, temperature, and neutral pressure
made in an electrostatic surface trap with numerical plasma simulations incorporating a number of alternative neutral models. 相似文献
986.
The kinetics of the silicon/hydrogen low-pressure discharge system have been measured using a flow technique and mass spectrometry. Results show that at long residence times the system operates under a partial chemical equilibrium even though it is not at thermodynamic equilibrium. The present work indicates that the decisive parameter controlling the structural properties of the deposit (i.e., the formation of either amorphous or microcrystalline silicon) is the departure of the system from the partial chemical equilibrium. 相似文献
987.
Discovery of the neutron in 1932 by Chadwick ushered in a new era of scientific research and technology. The neutron is endowed
with unique properties in its mass, life time, spin and magnetic moment etc and every important property has been used in
the study of condensed matter, biological molecules, nuclear forces, stellar objects and other fields. Neutron has a wide
range of applications in power production, breeding of fissile fuel, radiography, medicine and others. 相似文献
988.
The oxidation ofn-octene has been studied in mixtures with dimethylbutane, 1,4-dimethylcyclohexane, ethylcyclohexane, and dibutyl ether. Except for dimethylbutane, total yields increase on addition of a solvent, and the fraction of epoxide among the products is higher than in reactions with neat octene. 相似文献
989.
The double layer like potential jumps have been observed in a double plasma device. They do not correspond to a switching
of plasma potential from one metastable state to another but are caused by the ionisation of a very minute amount of the gas
that inevitably leaks into the system during the probe movement. 相似文献
990.