Charged particle focusing device

[motorman]

Hi,

Is there a device that can attract alpha or beta particles and focus them on a point.

Something like the reverse of a CRT tube for electrons.

BR,
Adam

 

[mfb]

They can be attracted by negative or positive charges, respectively. Not to a single point, but to a small volume, if the conditions are right.
Why do you want to do that?

 

[DrZoidberg]

http://en.wikipedia.org/wiki/Magnetic_lens