Test of image acceleration by distant collision of proton microbeam

Charged particles in front of surfaces always accelerate towards the surface due to the attractive image force between the charge and the surface. It is shown that using capillary transmission by charged particle projectiles the image acceleration can be clearly studied without close collision with the inner surface. We present experimental studies of the deflection of the proton microbeam with energy of 1 MeV as a function of the entering beam position parallel to the capillary axis when they pass through the steel macro-capillary.