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81.
82.
Rasmussen J.J. Schrittwieser R.W. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1991,19(3):457-501
Theoretical, numerical, and experimental investigations of the electrostatic ion-cyclotron instability (EICI) are critically reviewed. The discussion of theory focuses mainly on the linear theories, with particular attention to those that have been used in explaining experimental observations, but a short account of various nonlinear theories is also given. Numerical simulation results are surveyed. Experimental investigations in Q-machine plasmas and their interpretation in terms of various theories are then examined 相似文献
83.
Anders Bjarklev J rn Hedegaard Povlsen Karsten Rottwitt Ole Lumholt Thomas Rasmussen 《Fiber and Integrated Optics》1991,10(3):215-223
Erbium-doped fiber amplifiers (EDFAs) in eight different system configurations are investigated, using a full-scale model, and the midline placement of the amplifier is shown to be optimal. A distributed amplifier compared to the remote pumping scheme shows no system improvement. Use of a booster (next to the transmitter), a midline remote-pumped amplifier, and a preamplifier (next to the receiver) allows up to 180 km of extra transmission fiber to be added. 相似文献
84.
M.W. Guidry T.L. Nichols R.E. Neese J.O. Rasmussen L.F. Oliveira R. Donangelo 《Nuclear Physics A》1981,361(1):275-306
Semiclassical methods found to be highly accurate for inelastic scattering are applied to the calculation of rotational population signatures in heavy-ion two-neutron transfer reactions involving highly deformed targets. Basic features to be expected for such reactions are predicted, and are shown to have straightforward semiclassical interpretations. The rotational population signatures for 2-neutron transfer are shown to be quite different from those expected for the analogous inelastic scattering case. Several calculations are shown for Xe projectiles on rare-earth targets, and it is demonstrated that such reactions can provide a unique probe of nuclear structure in high angular momentum states. The extension of the general ideas employed here to 1-nucleon transfer in deformed nuclei and to several other examples of transfer to highly collective states in deformed and vibrational nuclei using very heavy ions is briefly considered. Experimental possibilities are discussed, and it is concluded that relevant experiments in this virtually unexplored area are possible using sophisticated particle-γ spectroscopic techniques. 相似文献
85.
86.
A nonlinear boundary value/initial value problem in two-phase filtration under gravity is solved analytically via the application of two successive Bäcklund transformations. 相似文献
87.
E.N. Kaufmann J.R. Brookeman P.C. Canepa T.A. Scott D.H. Rasmussen J.H. Perepezko 《Solid State Communications》1979,29(4):375-378
We report the first observation of nuclear quadrupole resonance (NQR) in Zn metal. A resonance line, which under the assumption of axial symmetry (η=0) corresponds to the transition in the ground state of 67Zn, has been found at v = 4.086(2) MHz at 4.2K. This yields (for η=0) a quadrupole coupling constant of MHz, which is the most accurate value currently available. 相似文献
88.
89.
D. G. Raich H. R. Bowman R. E. Eppley J. O. Rasmussen I. Rezanka 《Zeitschrift für Physik A Hadrons and Nuclei》1976,55(29):301-311
The isomer213mRa was produced by the reaction209Bi(10B, 6n), as well as by bombardments of12C on Pb isotopes,14N on Bi, and16O on natural Hg, with projectile energies in the range 60–100 MeV. The isomer decays with a halflife of 2.1 ms both via gamma internal transitions and via alpha branching to levels in209Rn. A level scheme is proposed in which the isomeric state is assigned as either 17/2– or 13/2+ with shell-model configurations either of theh
9/2 protons coupled to ap
1/2 neutron hole, or of an uncoupledi
13/2 neutron hole. On the basis of alpha decay rate predictions from the new Fliessbach theory, the 17/2– isomeric assignment is to be preferred.Phys. Abstracts classifications 4.200–4.375 相似文献