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Summary form only given. The microwave and millimeter wave region of the electromagnetic spectrum is ideally suited for the determination of plasma parameters such as electron density and temperature as well as more subtle phenomena such as collective waves and instabilities through exploitation of the frequency dependent properties of this dielectric medium. This spectral region is witnessing intensive...
Summary form only given. Broadband ELF (BBELF) electric field fluctuations are commonly observed in association with ion acceleration and outflow from the terrestrial auroral zone and ionosphere. These fluctuations are the conduit by which energy is transferred from macroscopic field and current systems to the ambient ion populations, and are thus an important part of the mass and energy flow between...
Summary form only given. There are two observations that are particularly ubiquitous in the auroral ionospheric plasmas: intense electric fields in density depleted regions, and transverse energization of ions emanating from such regions. The observed gain in ion energies is sufficiently large to allow the ions to gravitationally escape the ionosphere and populate the magnetosphere. The gain in energy...
Summary form only given. Current-free plasma expansion in a divergent magnetic field is surprisingly common and is found on a variety of spatial scales and in a variety of applications. Plasma expansion is essentially equivalent to a pressure gradient arising from a change in the plasma density. The density gradient can give rise to a potential gradient that retards motion of the lighter plasma electrons...
Summary form only given. Coronal mass ejections (CME's), sudden eruptions of coronal plasma and magnetic field into the interplanetary medium, are one of the most dynamic phenomena in the solar corona. These CME's are an important driver of space weather both through their interaction with the Earth's magnetosphere and through the magnetic reconnection and flaring which is driven in the solar corona...
Summary form only given. We show that in an electron-light ion-heavy ion plasma, the light component can rotate with a frequency, Omegar = (ZnH/ne)OmegaL where nH and ne are their densities, Z is the heavy ion charge state, and OmegaL is the light ion gyro-frequency. There is a current perpendicular to the magnetic field due to the light ion and electron EtimesB drift, which induces an electric field...
Summary form only given. A major facility for conducting ionospheric heating experiments is under development in Gakona, Alaska, as part of the high frequency active auroral research program (HAARP). Currently, HAARP HF transmitting system is being expanded from a phased-array antenna of 48 elements to one with 180 elements. After completion of this upgrading, its maximum effective radiated power...
Summary form only given. Long conductive structures immersed in flowing space plasmas have several potential science and engineering applications. Among them are propellantless in-orbit spacecraft tether propulsion and high-energy charge precipitation from the Earth's radiation belts, also known as remediation of radiation belts. In addition, the use of Langmuir probes as in-space plasma diagnostic...
Summary form only given. In this presentation we discuss a laboratory experiment for the investigation of instabilities associated with an electron beam subject to a magnetic compression of up to a factor of 30. Experimental results will be presented showing emission at a frequency of 11.7 GHz, corresponding to the relativistic cyclotron frequency, from a 42 keV electron beam subject to magnetic compression...
Summary form only given. The classical Child-Langmuir (CL) law has been the subject of interest for many years. Since it was first derived in the early twentieth century, many modifications have been made recently to include multi-dimensional, relativistic, and quantum effects. Including the effects of ion flows, bipolar CL law for classical and relativistic theory has been developed . However, the...
Summary form only given. A theory of non-relativistic, laminar, space-charge-limited, ellipse-shaped charged-particle beam formation is presented. In the elliptic diode, electrons or ions are accelerated by a static voltage differential and transversely focused by external electrodes. The electrode surfaces are derived as equipotentials external to the beam using a Laplace transform - Mathieu function...
Summary form only given. A burst RF (radio frequency, 195 kHz) inductively coupled plasma in a methane circumstance is generated with assistance of a pulsed carbon shunting arc discharge. The shunting arc is a metallic/semi-metallic plasma source without any trigger sources, and is ignited synchronously with the RF burst signal. The RF plasma was ignited at a methane pressure higher than 0.05 Pa and...
Summary form only given. In the report the experimental research results for the high-voltage discharge in air are presented on which basis the physical model of a discharge effectively generating runaway electrons in dense gas is constructed. The specified model assumes that a "spatial area" of electron transition to the runaway mode is originally formed near to a high-voltage electrode...
Summary form only given. Miniature discharges and their potential use for local area materials processing are investigated in this study. The objective of this study is to do materials processing steps including etching, surface activation, and plasma-assisted CVD on localized areas by applying a small discharge to only the region being processed. A miniature microwave plasma discharge applicator...
Summary form only given. A remarkable increase of highly charged ion beam current was observed when the electron cyclotron resonance ion source SERSE used a traveling wave tube-based generator (TWT) in place of a klystron, usually coupled to plasma chamber to sustain the ECRIS plasma. The preliminary results obtained with a different ion source were confirmed by the systematic measurements carried...
Summary form only given. The development of compact terahertz sources capable of output powers and efficiencies greater than 100 mW and 5%, respectively, will require electron beams of high current density (>50 A/cm2) and very small dimensions (~100 micron-scale). Generating such dense beams using thermionic emitters necessitates compressing the beam by about a factor of 10 which may negatively...
Summary form only given. High energy laser facilities such as OMEGA, and the future NIF and LMJ provide an unprecedented capability to generate steady, planar, ultra-high pressure shock waves (>2 TPa) in solid samples. Building on successful laser shock EOS experiments performed on a variety of laser facilities, we are designing experiments to perform impedance match experiments on Cu at 2.3 TPa...
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