# What is the typical strength of the electric field in a particle accelerator?

I am working on a research project involving the closed orbits of hydrogen in the presence of an external electric field and I am curious what a reasonable approximation for the electric field strength would be. I know that there are vast differences in particle accelerators but I have some information on other parts of the experiment set up that may help give a better approximation.
$1.$ The laser used to excite atoms to a higher energy state is a YAG laser producing light at $532nm$ that is then shifted to $698nm$ through an optics system.

$2.$ The molecular hydrogen beam $H_2$ operates at $4keV$.

Thanks for any information you can give.

• The max. experimental strength of an electric field is given by the field emission of metals. It's typically limiting RF cavities to approx. 10MV/m, so for a small experiment that's maybe 10V/um. You will have to be extremely careful with surface composition to get anywhere close to that before significant numbers of electrons will be emitted. – CuriousOne May 25 '15 at 21:34
• Thanks for your comment. Do you mind elaborating on what field emission and RF cavities are? – Lann625 May 25 '15 at 21:36
• See e.g. "Field emission in rf cavities" by B. Bonin for an easy overview with some nice examples and simple theory. The wikipedia article on field emission is rather rich. RF cavities are what is used in accelerators to increase the beam energy. For your purposes the design of cavities is irrelevant. – CuriousOne May 25 '15 at 21:38