The stability of a cusp magnetic field has been combined with the low loss rate of a closed field configuration in a series of three small toroidal devices designed for plasma containment. In operation, a pinch partly stabilized by an axial magnetic field, is produced prior to application of the containing cusp field. The axial stabilizing field of the pinch is then trapped by the plasma so that closed field lines are maintained within the plasma while the cusp is excluded from the plasma. There is no evidence of turbulence and the device exhibits a loss rate an order of magnitude below that to be expected from the same device operated as a minimum-B configuration without field trapping. Containment time is dependent on the decay rate of the applied cusp field. Maximum value of β within the plasma exceeds 2 and β remains above 1 for 15 μsec. Electron densities and temperatures exceed 1016 cm−3 and 105 °K, respectively.

Satellites on either side of the H3 line of hydrogen are reported at a displacement from H3 corresponding to the plasma frequency o;^ and twice such frequency. This anomalous behavior of the Hg transition is correlated with an oscillating electric field associated with plasma turbulence.Spectral line intensities and profiles, as influenced by local electric fields in a plasma, have been of recent interest both as a unique diagnostic tool to measure plasma parameters and as a problem of basic theoretical interest.^ "^ For instance, several papers reported the appearance of satellites near the 6632-A (2^P-3^P) forbidden transition in neutral helium. These satellites are produced by electric fields^ due to plasma oscillations, mixing the forbidden transition with the 6678-A (2^P-3^Z)) allowed transition. The second-order Stark effect gives a two-photon process that results in emission at V±(J), where v is the frequency of the forbidden transition, and CO is the frequency of the time-varying electric field due to the plasma.In this paper we report details of the observed profile of the H^ line in hydrogen, which is subject to first-order Stark effects, under the effect of high-frequency plasma fields. During plasma heating, the Hg exhibits satellites, arranged symmetrically about H3 and separated from the central line by ct)^ and 2(x>p, where (x>p is the plasma frequency.The observations were carried out in the Tormac plasma containment experiment, previously described.^ Plasma is created within a toroidal glass chamber 0.27 m in diameter. Subsequently, an //-centered^ (stabilized) pinch is produced, followed immediately by the application of a hexapole cusp magnetic field. The principal fields rise in about 10 /isec, during which time plasma density and temperature increase rapidly but uniformly to maximum values of approximately 10^^ m"^ and 15x10^ K. The fields decay slowly with the plasma exhibiting a containment time constant of about 200 /J,sec.

The fluorocarbon and nitrous oxide content of the stratosphere have been studied as a function of altitude, latitude, and time. Whole air samples have been gathered from a balloon platform, primarily through use of a cryogenic sampler. Twenty‐two flights were conducted between 1975 and 1980, and gas chromatography was utilized to determine species mixing ratios in the retrieved samples. Results are evaluated in terms of various stratosphere models.

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