ABSTRACT
Fig.1. Radial distributions: a - densities and flows densities (NF = 5 102 ) of charged particles, b) - electric field strength (NF = 1.6 102) and potential (NF = 20) for N0(0) = 1.2 1011 cm 3, T, = 1.14 eV, Z = 8.79 102 1/s
The applicability of a Bohm's criterion of development of a sheath of a space charge near the wall was parsed also. As shown calculations, at pressures 1 Torr a sheath, as a rule, is collisional and, entering in a
T sheath, the ions can have velocity much less of an ions sound velocity usi = . For example, for an intro-
duced case the quantity of drift velocity of an ion even on boundary of a wall of a tube achieves u, vt-•• 7104 cm/s. At small pressures, as displays the analysis, there is a problem of exposition of a motion of ions in a field of a sheath of a space charge near the wall.
