抄録
This paper reports co-existence of the moving striation and the helical oscillation in the positive column in a longitudinal magnetic field. The existing regions for these oscillations are graphically obtained in relation to the magnetic field and the electric field of the column and the experimental results of the co-existence can be explained by the graph. In very short tube, thee is no critical magnetic field therefore no helical oscillation but instead the moving striation up to very large magnetic field. The striation is also affected by external conditions such as discharge current, heater current etc.
