Disturbances of the ambient magnetoplasma due to its interactions with object surfaces. Imaginary emission method. Far-wake of objects moving through a rarefied plasma at different angles to the ambient magnetic field

A method of “imaginary emission”, which allows a simple analytical description of plasma disturbances due to an object in motion at an arbitrary direction to the magnetic field, is proposed. This method can be applied to the investigation of reflections; secondary particle emissions for any particle hitting an object surface, photoemission effects, and the effects of absorption. In addition, the “imaginary emission” method makes it possible to simulate plasma disturbances due to interactions of arbitrary shape objects with the ambient magnetoplasma, and the object (or a set of objects) can be in motion with time-dependent velocities or at rest. According to this method imaginary emission sources have been defined for arbitrary shape objects. The complex processes of interactions of the ambient plasma with the object surface have been included as reflections, secondary particle emissions for any particle hitting an object surface photoemission effects and the effects of absorption. The special cases of absorption and direct reflection of any particle impinging on the object surface are considered in detail. As applications of the imaginary emission method, the disturbances of the charged-particle concentration in the ambient plasma for the following specific cases are calculated. e far wake of the moving object under the condition that the maximal cross-section of the object (with reference to the direction of V) is the small plate dS and L⊥∥V∥ ⪢ L∥νthi where L⊥ is the minimal size of the maximal cross-section of the object, L∥ the parallel size (the length) of the object (with reference to the direction of V), V the object velocity, and νthi the mean thermal velocity of ions. he far wake of the space platform (or solar battery) if the velocity of the platform V is perpendicular to their normal n and the condition of point (i) is not satisfied. kes of objects in the satellite attitude regime have been considered (above 200 km), where the object velocity is well above the thermal velocity of ions and very small compared to the thermal velocity of plasma electrons. the structure of the far wake is dominated by the ambient magnetic field, instead of electric fields effects. The analytical results describe a flute formation along the edges of the surfaces of constant disturbances of the ambient plasma concentration for the objects rapidly moving parallel or approximately parallel to the ambient magnetic field. In the case of the objects in motion perpendicular or approximately perpendicular to the ambient magnetic. field, developing field aligned striations are obtained of surfaces of constant disturbances of the ambient plasma concentration.