On the experiments of Surfatron concept with use of capillary plasma.

In the middle of 1980th, the VpxB concept for accelerating electrons are found by Nishida et al, with the use of plasma wave excited by high power microwave in the interaction with weakly magnetized plasma. This acceleration concept was called “Surfatron effect” in the relativistic regime. However, there is no experimental evidence so far in the relativistic regime, although the acceleration efficiency is highest in all of the concepts based on the plasma wave acceleration scheme, and we are now under experiments. In order to make longer the acceleration distances, there are several ideas including 1)ducting of the electromagnetic waves (EM wave) in the preformed plasma, 2)selfchanneling of the EM waves, and others. In this paper, the experimental results are shown on the ducting phenomena by using strong microwave for simulating the laser ducting, and on the capillary plasma scheme