Engineering topics

Temerin, M.

Publications and source records attributed to Temerin, M..

21 records · Page 2

NASA NTRS1980

Rocket-borne wave measurements in the dayside auroral oval

VLF and ELF waves were measured on two rocket payloads launched into the dayside auroral oval on Dec. 18, 1974, and on Jan. 11, 1975. The correlation of the VLF hiss intensity with the fluxes of precipitating electrons above 500 eV on short spatial and time scales was often poor, even when a positive slope existed in the electron phase space density. During the flight in 1975, distinct features were observed at the lower hybrid frequency; the frequency of this emission was used together with an independent density measurement to determine the relative concentration of O(+) to the heavier ions NO(+) and O2(+). It was found that the density of NO(+) or O2(+), which could not be distinguished, is enhanced over expected values between 150 and 400 km altitude. Broadband electrostatic and electromagnetic waves were observed after the barium-shaped charged explosion in 1975; the observed lowering of the auroral VLF hiss cutoff due to the barium is consistent with either ducting of VLF hiss emissions along the enhanced density duct produced by the barium or with local generation VLF hiss during the barium injection.

Temerin, M.↗

NASA NTRS1980

Observations of ULF electric field fluctuations in the dayside auroral oval

Electric field oscillations at frequencies centered below 10 Hz were measured by a payload equipped with double-probe electric field detectors which was launched into the dayside auroral oval during the Greenland rocket campaign on January 11, 1975. These oscillations exceeded an amplitude of 3 mV/m broadband and occurred over a period of about 90 s. These oscillations occurred during a proton injection event when the quasi-static electric field was less than 20 mV/m on the average. However, during a brief 2-s interval the electric field exceeded 50 mV/m. Analysis of the amplitude as a function of the spin frequency showed that the electric field was confined to a plane perpendicular to the magnetic field. The power spectrum was of the form f to the -6.5 + or - 1.5 power, where f is the frequency over the range from 8 to 18 Hz. The existence of a large electric field fluctuation in a spatially or temporally confined region of low-amplitude turbulence suggests that this may be an observation of the low-altitude projection of a turbulent region associated with electrostatic shocks which have recently been observed at higher altitudes.

Temerin, M.↗

NASA NTRS1980

Ion heating by strong electrostatic ion cyclotron turbulence

A theory of the ion heating due to electrostatic ion cyclotron (EIC) waves in the auroral zone is presented. Due to the slowly convecting nature of the EIC mode, quasi-linear plateau formation cannot stabilize the waves, and growth occurs until the nonlinear mechanisms of ion resonance broadening and electron trapping provide saturation. The large amplitude and coherent nature of the resulting wave imply that quasi-linear theory provides only a lower limit to the ion heating. An upper bound on the heating rate is derived using a time-average model of ion dynamics in the coherent waves. The effects of ion heating in the presence of the magnetic gradient force and parallel electric fields are considered, with the result that perpendicular energies over 100 eV are easily attainable from a 1 eV source plasma. Perpendicular heating in the absence of a parallel electric field yields conical ion distributions, which in the presence of an electric field become field-aligned beams.

Lysak, R. L.↗