This disclosure relates to systems and methods detecting a change in pressure, wall shear flow, or both. The method includes generating DC plasma having an electrical field based on an input DC voltage and a DC current, detecting changes to the electrical field, and identifying a change in wall shear flow, pressure, or both based on the change in the electrical field when the DC plasma is disposed in a flow field.

A Hall-effect thruster assembly includes a plurality of magnetic sources for creating a magnetic circuit. The plurality of magnetic sources are positioned between a first end and a second, opposite end of the Hall-effect thruster. The plurality of magnetic sources define a longitudinal axis extending through the first end and the second end. The first end is configured as a discharge end. A mount assembly is coupled to the second end. The mount assembly is configured to secure the plurality of magnetic sources to a spacecraft. A magnetic element is supported by the mount assembly. The magnetic element is positioned relative to the plurality of magnetic sources by the mount assembly.

A reflective optical system (100) comprising at least one reflective aspheric surface (1) of focal length f.sub.0 and optical axis (Z), the surface being configured so that an incident laser beam (2) propagating along an axis (Z′) is focused along the optical axis (Z) with a FWHM ((Full Width at Half Maximum) of the intensity of the reflected beam along the optical axis (Z) being larger, preferably by a factor of at least 10, than the FWHM of the intensity of a focused beam reflected by a parabola having same focal length f.sub.0 and same optical axis (Z), receiving same beam.

A reflective optical system (100) comprising at least one reflective aspheric surface (1) of focal length f.sub.0 and optical axis (Z), the surface being configured so that an incident laser beam (2) propagating along an axis (Z′) is focused along the optical axis (Z) with a FWHM ((Full Width at Half Maximum) of the intensity of the reflected beam along the optical axis (Z) being larger, preferably by a factor of at least 10, than the FWHM of the intensity of a focused beam reflected by a parabola having same focal length f.sub.0 and same optical axis (Z), receiving same beam.

The invention relates to an ion thruster, comprising: a chamber, a reservoir, comprising a solid propellant (PS), housed in the chamber and comprising a conductive jacket provided with an orifice; means for forming an ion-electron plasma in the chamber, which means are able to sublime the solid propellant in the reservoir, then to generate said plasma in the chamber from the sublimed propellant coming from the reservoir through the orifice; a means for extracting and accelerating the ions and electrons of the plasma out of the chamber, which means comprises at least two grids at one end (E) of the chamber; a radiofrequency AC voltage source for generating a radiofrequency signal comprised between the plasma frequencies of the ions and of the electrons, arranged in series with a capacitor and connected, by one of its outputs and via this capacitor, to one of the grids, with the other grid being connected to the other output of said voltage source;
said means for extracting and accelerating and said voltage source making it possible to form, at the output of the chamber, an ion-electron beam.

The invention relates to an ion thruster, comprising: a chamber, a reservoir, comprising a solid propellant (PS), housed in the chamber and comprising a conductive jacket provided with an orifice; means for forming an ion-electron plasma in the chamber, which means are able to sublime the solid propellant in the reservoir, then to generate said plasma in the chamber from the sublimed propellant coming from the reservoir through the orifice; a means for extracting and accelerating the ions and electrons of the plasma out of the chamber, which means comprises at least two grids at one end (E) of the chamber; a radiofrequency AC voltage source for generating a radiofrequency signal comprised between the plasma frequencies of the ions and of the electrons, arranged in series with a capacitor and connected, by one of its outputs and via this capacitor, to one of the grids, with the other grid being connected to the other output of said voltage source;
said means for extracting and accelerating and said voltage source making it possible to form, at the output of the chamber, an ion-electron beam.

The invention provides a plasma production and control device that may be used in propulsion (e.g., satellite propulsion) and/or industrial applications. The plasma production system comprises a unidirectional magnetic field.

A pulsed metal plasma thruster (MPT) cube has a plurality of thrusters, each having a first cathode electrode and a trigger electrode separated from the first electrode by an insulator sufficient to support an initiation plasma, and a porous anode electrode positioned a separation distance from the face of all of the cathode electrodes. The cathode electrode can be either the inner electrode or the outer electrode. A power supply delivers a high voltage pulse to the trigger electrode with respect to the cathode electrode sufficient to initiate a plasma on the surface of the insulator. The plasma transfers between the anode electrode and cathode electrode of selected thrusters, thereby generating a pulse of thrust.

Provided herein are various leptonic power sources, leptonic control systems, and leptonic-powered engines. In one example, an apparatus includes a housing having apertures through which material can enter and exit, and an anode coupled to the housing upstream from a cathode. A leptonic source emits beam electrons into the housing to ionize the material into a plasma according to a selectable ionization degree and deposit charge onto the cathode to establish an electric field in the plasma. A magnetic field source produces a magnetic field in the plasma at selectable angle to the flow of the plasma to at least partially entrain plasma electrons. Ions of the plasma are accelerated downstream in the housing by the electric field and impart momentum to a portion of the material to produce a thrust proportional to the selectable ionization degree of the plasma and a selectable intensity of the electric field.

A neutralizer suitable for use in an ion engine comprises a halogen gas source and an electrode tube comprising an inlet opening connected to the halogen gas source for supplying a halogen gas provided by the halogen gas source into the electrode tube, a discharge space for generating a plasma from the halogen gas supplied into the electrode tube, and an outlet opening for discharging the plasma generated in the discharge space and free electrons from the electrode tube. An electron emitter is arranged in the discharge space of the electrode tube, which is at least partially made of tungsten, a tungsten alloy or a tungsten composite material containing at least one of iridium, rhenium, ruthenium, rhodium and osmium.