Triggered Spark Gap

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Original poster: "Kelly & Phillipa Williams by way of Terry Fritz <twftesla-at-qwest-dot-net>" <kellyw-at-ihug.co.nz>

Dear All,

While reading my physics textbook this week I came up with a really neat, if
fairly esoteric, idea for a triggered spark gap.

All metals have a certain energy barrier preventing electrons from leaving
the surface of the metal. (Analougous to a rounded curb at the edge of a
flat road, it keeps a slow-moving soccer ball on the road unless it is
kicked hard enough.) This energy can be provided by heating the metal very
hot (thermionic emission),

Or by bombarding the metal with photons (light) of a high enough frequency
so that when an electron on the surface absorbs a photon, it jumps off the
metal.

Now suppose an enclosed spark gap in a box, surrounded by an xenon
flash-tube or similar source of light.
The electrodes a slightly too far for the voltage to jump alone, but when
the tube flashes and the electrons jump off the metal they ionise gas and
fly across to the other electrode, thus initiating the spark. I know this
effect occurs in a slight vacuum, but I would have to investigate it's
effect in air.

The only problem is that the cut-off frequency for this emission for many
metals, and tungsten too I would imagine, is in the ultraviolet range and
slightly above.

Could those with a working knowledge of x-ray tubes tell me whether an x-ray
tube can be PULSED at 100 (50 Hz)
or 120 (60Hz) to trigger a gap like this? Forced air quenching may also be
necessary, although this technique could be applied to a single static gap
all the way through a multi-gap-static-gap, provided the metal of the gap
itself was exposed.

I would very much appreciate knowing whether vacuum tubes can be pulsed -
maybe a pulsed supply to the x-ray tranny, would that work?

Best Regards,

Alan Williams