On Jun 25, 2007, at 3:09 AM, Michel Jullian wrote:
OK Bill you have convinced me that water droplets emitted at low
fields might not Coulomb-explode (low field = low charge on each
droplet, e.g. a single elementary charge) and therefore might form
a thin linear chain along the line of maximum field, so that this
phenomenon could explain your air threads observations in the wet
emitters cases. But as I recall you also managed to obtain those
air threads using dry emitters such as the edge of a torn piece of
paper, so the low current corona explanation may be the correct one
in those cases.
Regarding the turn-on field for corona which you suggest might be
too high for corona to be involved in the airthread phenomenon,
note that domestic corona ion generators also operate with only a
few kV over a few tens of cm (distance to the nearest wall, floor
or ceiling which acts as the collecting plate), so "dry" corona
does turn on at very low fields and very low currents, although
maybe not in the same mode as when operated at higher fields.
Another thing occurs to me, maybe the reason why you couldn't get
thin beams with needles is that you didn't drive them through a
high series resistance, which for proper comparison would have to
be of the order of the resistance of your "insulating" emitters
such as paper fibers (hundreds of megohms?). Maybe the high
resistance could have the effect of producing only short bursts of
ions by ohmic voltage drop, participating in the low current and
therefore the low sideways expansion.
It could also be that the fibers, being very thin, achieved a better
sideways (radial) field gradient and thus made better water
collectors, and also sustained a much better bond with the water
vapor and CO2 from the atmosphere and thus anchored the top of a
water filament. Experiment should sort this out. The problem is it
is difficult to justify the time and expense of the experiment when
there are so many others of potentially world changing significance.
Say, the server is not responding for:
http://amasci.com/weird/unusual/airexp.html
Regards,
Horace Heffner
