Re: lightning, Xrays

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

Original poster: "Malcolm Watts by way of Terry Fritz <teslalist-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Jim,

On 26 Feb 2003, at 18:02, Tesla list wrote:

 > Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
<jimlux-at-earthlink-dot-net>
 >
 > I see from the news
 > http://www.napa.ufl.edu/2003news/lightxray.htm
 >
 > that there has been experimental measurement of Xray emission from
 > lightning strokes.
 >
 > It's historically been the case that you needed both HV and High Vacuum to
 > get Xrays.  Therefore, there's no radiation hazard from, e.g., a tesla coil.
 > Here's a case (not likely to be duplicated by the casual amateur) where you
 > get Xrays with HV, but no vacuum.
 > I was aware that you can get Xrays from very fast rise time sparks (>1E9
 > A/microsecond, as I recall), but this is something new...
 >
 > It's also in Science, vol 299, page 694-697 "Energetic Radiation Produced
 > by Rocket-Triggered Lightning", J.R.Dwyer, et.al.

The key word there might be "triggered". Question is, do X-rays occur
if there is no metal present in the discharge path? All those man-
made devices that produce X-rays "in a vacuum" are firing energetic
electrons at metal targets.

Regards,
Malcolm