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HMS-776
Sep21-09, 11:28 AM
I have been wondering how an atom is ionized and multiply ionized in an electric field?

In a single ionization, does only one electron go through each transition until it is ionized?

What about in a multiple ionization?

Would the first electron travel through all transitions while the other electrons remain at their ground state? And after the first ionization will the next electron travel through it's transitions until it becomes ionized etc etc?

Or will all the valence electrons travel through their transitions and become ionized at the same time?

Bob S
Sep21-09, 11:55 AM
dear HMS-
Look at my posts in your other threads. Look especially at the ionization thresholds (steps) in beryllium 1s and 2s cross sections in
http://xdb.lbl.gov/Section1/Sec_1-5.html
Usually the ionization threshold for the first electron is the lowest. Once an atom is ionized, the ion will accelerate in an electric field, and collisional ionization becomes possible. In electric field ionization, another possible complication is electron ionization of atoms by a free accelerated electron resulting from an electric field induced ionization of another atom. This is the source of multiplication in Geiger-Muller tubes and proportional counters.
[Edit] See this abstract on laser induced tunneling ionization:
http://www.sciencemag.org/cgi/content/abstract/325/5946/1364
Bob S

HMS-776
Sep21-09, 04:36 PM
Thanks for the Links and info BOB S! It is appreciated!