🚀 go-pugleaf

  If there is anyone out there who knows anything about gas discharge tubes I
am trying to find an explanation for the following effect which was recently
described to me.

  The apparatus was a standard discharge tube, i.e. simply a glass tube with
high voltage electrodes at either end.  The tube was initially evacuated and
was allowed to slowly fill with gas.  As the pressure increased the expected
fluorescence occurred, but rather then involve the entire gas volume it was
confined to a band which formed at one electrode and then began to propagate
down the length of the tube (as a function of pressure).  Additional bands
appeared and followed the first keeping an equal spacing between bands.
Finally five distinct bands were present which eventually stopped moving, 
intensified and merged into a uniform discharge.  Note that the gas pressure
was allowed to increase continuously throughout this process.

  The question I have is what effect would account for physical structure in
the discharge?  Why would a distinct band form rather then a discharge through
the entire tube, or perhaps a number of equally spaced bands appearing
simultaneously down the length of the tube?

  If you happen to know the explanation please drop me an email reply or post
a response to the net.

				Thanks...
 			        Richard Soluk