Matches in SemOpenAlex for { <https://semopenalex.org/work/W1625425816> ?p ?o ?g. }
Showing items 1 to 70 of
70
with 100 items per page.
- W1625425816 abstract "A study of the high frequency properties of a low temperature plasma column in a longitudinal magnetic field is described. The experimental observations give a relatively complete picture of the microwave (extraordinary mode) properties of the plasmas studied, encompassing continuous wave scattering and noise emission measurements, as well as the demonstration of the occurrence of related echo processes. Theoretical developments deal largely with a physical model consisting of a one-dimensional slab of cold (zero temperature) plasma which is nonuniform in the steady state and immersed in a uniform magnetic field. Data on the continuous wave reflection and noise emission from some afterglow rare gas discharges are given. The electron temperature in these plasmas is low, approaching room temperature. The reflection and emission are measured as a function of magnetic field in the vicinity of electron cyclotron resonance with electron density as a parameter. The electron densities are such that (ωp/ω) ≤ 1 , where ωp is the electron plasma frequency and ω is the signal frequency. Both types of experiment show the presence of collective effects which yield a normal mode spectrum strongly dependent on the electron density. A broad peak is observed in the region (ωc/ω) ≤ 1 where ωc is the electron cyclotron frequency. This peak shifts to lower values of (ωc/ω) and broadens as the electron density increases. For all values of electron density, a sharp peak is found very close to (ωc/ω) = 1, the cyclotron resonance condition. The experimental and theoretical results suggest that the phenomena observed involve resonance effects at the upper hybrid frequencies (ωh2 = ωc2 + ωp2) of the plasma. Data are also given on a new two-pulse echo process which occurs in these after-glow plasmas. The results establish the intimate relation between the echoes and the upper hybrid normal modes studied in the CW experiments, demonstrating the dominant role played by collective effects in the formation of this echo. A weakly nonlinear cold plasma theory yields upper hybrid echoes which are strongest in a narrow band of frequencies near the maximum upper hybrid frequency of the nonuniform plasma, in agreement with experiment. Furthermore, large signal computations of the dependence of the echo amplitude on excitation pulse separation and amplitude show a complex behavior in qualitative agreement with experiment. As a supplementary topic, the properties of echoes from a general collection of anharmonic oscillators are discussed. The oscillators in this discussion are a general mathematical analog of the upper hybrid normal modes of a cold nonuniform plasma. Through emphasis of effects due to the finite width of the excitation pulses, the calculations show explicitly the role of the various characteristics of the oscillators in echo processes, further delineating the general features thought requisite of classical multiple-pulse echo systems." @default.
- W1625425816 created "2016-06-24" @default.
- W1625425816 creator A5068032910 @default.
- W1625425816 date "1968-01-01" @default.
- W1625425816 modified "2023-09-27" @default.
- W1625425816 title "Echoes and Scattering From Plasma in a Magnetic Field" @default.
- W1625425816 doi "https://doi.org/10.7907/ery7-7a19." @default.
- W1625425816 hasPublicationYear "1968" @default.
- W1625425816 type Work @default.
- W1625425816 sameAs 1625425816 @default.
- W1625425816 citedByCount "0" @default.
- W1625425816 crossrefType "dissertation" @default.
- W1625425816 hasAuthorship W1625425816A5068032910 @default.
- W1625425816 hasConcept C115260700 @default.
- W1625425816 hasConcept C120665830 @default.
- W1625425816 hasConcept C121332964 @default.
- W1625425816 hasConcept C125485243 @default.
- W1625425816 hasConcept C132427895 @default.
- W1625425816 hasConcept C147120987 @default.
- W1625425816 hasConcept C175361016 @default.
- W1625425816 hasConcept C184779094 @default.
- W1625425816 hasConcept C191486275 @default.
- W1625425816 hasConcept C192304548 @default.
- W1625425816 hasConcept C22175881 @default.
- W1625425816 hasConcept C2779146573 @default.
- W1625425816 hasConcept C39527238 @default.
- W1625425816 hasConcept C62520636 @default.
- W1625425816 hasConcept C82706917 @default.
- W1625425816 hasConceptScore W1625425816C115260700 @default.
- W1625425816 hasConceptScore W1625425816C120665830 @default.
- W1625425816 hasConceptScore W1625425816C121332964 @default.
- W1625425816 hasConceptScore W1625425816C125485243 @default.
- W1625425816 hasConceptScore W1625425816C132427895 @default.
- W1625425816 hasConceptScore W1625425816C147120987 @default.
- W1625425816 hasConceptScore W1625425816C175361016 @default.
- W1625425816 hasConceptScore W1625425816C184779094 @default.
- W1625425816 hasConceptScore W1625425816C191486275 @default.
- W1625425816 hasConceptScore W1625425816C192304548 @default.
- W1625425816 hasConceptScore W1625425816C22175881 @default.
- W1625425816 hasConceptScore W1625425816C2779146573 @default.
- W1625425816 hasConceptScore W1625425816C39527238 @default.
- W1625425816 hasConceptScore W1625425816C62520636 @default.
- W1625425816 hasConceptScore W1625425816C82706917 @default.
- W1625425816 hasLocation W16254258161 @default.
- W1625425816 hasOpenAccess W1625425816 @default.
- W1625425816 hasPrimaryLocation W16254258161 @default.
- W1625425816 hasRelatedWork W1522982145 @default.
- W1625425816 hasRelatedWork W177152075 @default.
- W1625425816 hasRelatedWork W1784232257 @default.
- W1625425816 hasRelatedWork W193054132 @default.
- W1625425816 hasRelatedWork W1966219509 @default.
- W1625425816 hasRelatedWork W1974498030 @default.
- W1625425816 hasRelatedWork W1978349832 @default.
- W1625425816 hasRelatedWork W1998767047 @default.
- W1625425816 hasRelatedWork W2000138212 @default.
- W1625425816 hasRelatedWork W2021316798 @default.
- W1625425816 hasRelatedWork W2021637729 @default.
- W1625425816 hasRelatedWork W2027347125 @default.
- W1625425816 hasRelatedWork W2056641016 @default.
- W1625425816 hasRelatedWork W2094206589 @default.
- W1625425816 hasRelatedWork W2106441796 @default.
- W1625425816 hasRelatedWork W211772808 @default.
- W1625425816 hasRelatedWork W2319363264 @default.
- W1625425816 hasRelatedWork W2481577017 @default.
- W1625425816 hasRelatedWork W2803537454 @default.
- W1625425816 hasRelatedWork W230392871 @default.
- W1625425816 isParatext "false" @default.
- W1625425816 isRetracted "false" @default.
- W1625425816 magId "1625425816" @default.
- W1625425816 workType "dissertation" @default.