Positive column of a helium discharge in transition from the homogeneous to the striated state

摘要

The critical conditions for appearance or disappearance of striations in the positive column of a helium discharge are expressable in terms of discharge current, gas pressure, and tube radius as I=A/(pR)5. For I in mA, P in Torr, and R in cm, A ranges from 160 to 30, depending upon position of observation from cathode to anode end of positive column.