摘要:

A beam‐plasma system consisting of a focused light ion beam propagating through az‐discharge plasma is analyzed for electromagnetic velocity space instabilities. In particular, the Weibel (k⋅B0=0, k⋅Vz≃0) and the whistler (k×B0≃0, k⋅Vz=0) instabilities are studied. It is found that unstable modes do not grow fast enough to affect the beam propagation in a pellet‐fusion‐reactor chamber. For k⋅Vz≳0, the instabilities convect with a velocity much less than the beam streaming velocity.

ISSN:0031-9171    

DOI:10.1063/1.863223

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The conventional cloud‐in‐cell vortex representation of the two‐dimensional Euler equations is modified to allow energy injection from small scales. A simulation of the inverse cascade yields an energy spectrum consistent withk−5/3and a Kolmogoroff constant of 14.

ISSN:0031-9171    

DOI:10.1063/1.863225

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Under subcritical conditions, it is shown that a spatial variation of the velocity amplitude of convective rolls is accompanied by a modification in their wavenumber which takes values lower than the critical one.

ISSN:0031-9171    

DOI:10.1063/1.863234

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The distortion of a two‐dimensional drop in a slow viscous flow is computed up to the limiting configuration in which opposite sides of the drop touch one another.

ISSN:0031-9171    

DOI:10.1063/1.863235

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The Whitham equation for the wave dispersion &ohgr;/k=(1+k2)−1is shown to be equivalent tout+ux−uxxt+uux−(uu@qLx)xx=0. By studying its stationary wave solutions, it is shown that there exists a critical value of the speedc(=4/3) above which this weakly nonlinear theory becomes internally inconsistent.

ISSN:0031-9171    

DOI:10.1063/1.863236

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

It is observed experimentally that stimulated Raman backscattering is enhanced whenever the electron gyrofrequency corresponds to the pump frequency or the scattered frequency in the electron frame of motion.

ISSN:0031-9171    

DOI:10.1063/1.863237

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Scale‐separation arguments underlying the balloning representation are employed to demonstrate that its coefficients are uniquely determined by the original function, contrary to certain suggestions in the literature. An explicit formula for inverting the series is displayed.

ISSN:0031-9171    

DOI:10.1063/1.863238

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Recursive behavior has been observed in a two‐dimensional electrostatic particle simulation of a coherent intense Langmuir wave packet. The recursion may be associated with the fact that the plasma frequency has a spatial variation in the density depression created by the ponderomotive force.

ISSN:0031-9171    

DOI:10.1063/1.863239

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Time resolved backscatter spectra, recorded during high intensity (1016W/cm2) irradiation of moderate density scale length plasmas, show a time‐dependent mode structure.

ISSN:0031-9171    

DOI:10.1063/1.863240

出版商:AIP    

年代:1981

数据来源: AIP