The thruster has a magnetic circuit for creating magnetic filed in a main annular ionization and acceleration channel. The circuit has external and internal radial polar pieces (134, 135) defining an internal concave peripheral surface (134a) and an external convex peripheral surface (135a), respectively. Each surface has an adjusted profile different from a circular cylindrical surface to form a variable width air gap. The width of the gap is maximum in zones (232) at the right of external coils and minimum in zones (231) between the coils to create a uniform radial magnetic field.
展开▼
