Re: Ionization at 80eV

["Dale E. Boyce" <dale@radpro.uchicago.edu>]

80 ev (alphas) will be moving to slowly to ionize an atom or molecule.
The electrons in the (atom) will be moving rapidly enough to allow
for adiabatic relaxation to prevent an ionization to occur.  What
Wes said about needing to exceed the dielectric constant is correct
for electric fields.  The reason arc welders get a spark may be because
the gap gets small enough to cause the field to exceed the dielectric
constant, but more likely from momentary contact raising the temperature
enough that electrons are emitted probabilistically.  Once some ionization
occurs a current can be established and maintained even with a macroscopic
gap at relatively low voltages.

Dale