Re: Speed of Streamer formation

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>" <davep-at-quik-dot-com>

Tesla list wrote:
> 
> Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jimlux-at-earthlink-dot-net>
 
> > I suggest that gradual growth of streamer length may be due
> > to increasing number of ions present in the immediate
> > vicinity.  Recombination (and air mixing) take a finite
> > period of time...
 
> The "burning" question.. how long?

	Dunno.
	I Assume the answer is out there, at least for some gases
	at some temperatures....

> Clearly, it's not just the cooling of the plasma until it stops
> conducting (which happens VERY fast, considering that there's a
> pretty sharp knee in the conductivity vs temp curve).

> Although, the radiation cooling (probably dominant?) does go as T^4,
> so it might stay pretty hot, but not radiant (at least in visible..).
> Hmmm..

	Indeed.  I suggest the issue is electrons dropping back down
	the orbital levels, which can be cooling, per se, or other
	factors.  (Note that lifetime of 'population inversion'
	(electrons in high orbitals) is critical to laser function.)
	More so: the ions involve electrons physically separated from
	atoms.  They need to travel home.  This CAN happen quickly,
	or slowly (milliseconds, longer) depending on pressure, gas, etc.

> This is an area that isn't covered by much of the spark literature.....

	I'd look into physics work on conduction in gases: Cobine, Gaseous
	Conductors.