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Satellites
Published in Mohammad Razani, Commercial Space Technologies and Applications, 2018
On February 16, 2007, five THEMIS satellites were launched by a DELTA II rocket from Cape Canaveral, Florida. The main objective of THEMIS is to determine the place of release and the nature of the macroscopic process responsible for the substorms, and to study their relations and couplings. Another objective was to study the radiation belts, the magnetopause, and the border layers. Each of the satellites is equipped with five instruments: FGM (FluxGate Magnetometer)EFI (Electric Field Instrument)ESA (electrostatic analyzer)SCM (search coil magnetometer)SST (solid-state telescopes)
Plasma waves beyond the solar system
Published in B. Raneesh, Nandakumar Kalarikkal, Jemy James, Anju K. Nair, Plasma and Fusion Science, 2018
The initial data on interplanetary medium from spacecraft measurements was first obtained in early 1960s. The first attempt of simultaneous measurements of plasma velocity and the magnetic field in the interplanetary space was carried out by Mariner-2 in 1962. This spacecraft used positive ion spectrometer comprised of a cylindrical electrostatic analyzer and a flux-gate magnetometer when it was on its way to Venus. The main objective of this exercise was to find the properties of simultaneous variations in the magnetic field and the plasma velocity and to verify if the variations were generated by the hydromagnetic waves. The hydromagnetic waves are low frequency ion oscillations which take place in the presence of a magnetic field and have two main modes: Alfvén waves (along) and Magnetosonic waves (across) the magnetic field. However, the results were not conclusive [5].
Electrical, Physical, and Chemical Characterization
Published in Robert Doering, Yoshio Nishi, Handbook of Semiconductor Manufacturing Technology, 2017
Dieter K. Schroder, Bruno W. Schueler, Thomas Shaffner, Greg S. Strossman
Although originally focused toward surface analysis of the topmost monolayer(s), Time-of-flight (ToF) SIMS spectrometers have lately been employed in depth profiling applications. Time-of-flight-SIMS employs a pulsed primary ion beam of nanosecond duration to strike the surface, generate secondary ions, and transport them through an electrostatic analyzer to the detector. Because all secondary ions basically travel along the same path through the analyzer and mass separation is solely due to flight time differences from the sample to the detector, a ToF analyzer is capable of detecting any secondary species of given polarity over a mass range 1 kDa to some 10 kDa and m/Δm up to 15,000. As a consequence, ToF-SIMS has unsurpassed overall (parallel) detection sensitivity per surface layer. The material removal rate using a pulsed primary ion beam alone is so slow (some nanometer per hour) that the depth profile analysis requires the additional alternating use of a sputter ion beam (10 s of μs in duration) to advance in depth. None of the material removed by the sputter beam can be mass analyzed. A ToF-SIMS depth profile is in essence a sequence of complete surface analyses at increasing depth from the surface, i.e., the depth profiles of all detectable ions species are collected in a single analysis. Depending on the mode of operation, the depth range of analyses covered with ToF-SIMS is between the surface to (reasonably) some 100 nm.
Plasma Waves Around Comets
Published in IETE Technical Review, 2022
The RPC suite consists of five plasma instruments: Langmuir Probes (RPC-LAP) have dual sensors to measure the plasma parameters such as plasma number density, plasma temperature, plasma flow velocity, etc. It is designed in such a way that it can also measure the spacecraft potential and time-varying electric field up to 8 kHz [52].Mutual Impedance Probe (RPC-MIP) to measure the plasma wave electric field in the range of 7 kHz – 3.5 MHz by sensing the capacitive coupling between the two electrodes when passive. When active, the MIP can measure the electron plasma frequency from which the electron number density and temperature can be estimated [53].Ion Electron Sensor (RPC-IES) consisted of two electrostatic analyzers one each to measure the ion and electron distributions to distinguish the heavy ionized atomic and molecular species of cometary origin from the incoming solar wind [54].Ion Composition Analyser (RPC-ICA) is an electrostatic analyzer to study the solar wind – comet interaction thereby measuring the 3-D positive ion distribution function [55].Magnetometer (RPC-MAG) has dual triaxial fluxgate magnetic sensors to measure the magnetic field around the C–G in the region of its interaction with the incoming solar wind [56].