Magnetic Bending of Laser Guided Electron Beams

Experiments have been performed to study magnetic turning of laser-guided electron beams. This technique is of interest for beam transport in circular high-current electron beam accelerators such as Sandia's recirculating linac. A 1-MeV, 2-kA, 50-ns, electron beam was turned through a 45° angle with > 90% current transport efficiency. The 45° bend was accomplished by switching the beam between two laser ionized guide channels which intersected in the center of a 680 Gauss turning magnet. The beam radius was observed to increase as a result of turning by the uniform field in agreement with single particle simulations. These simulations predict much smaller emittance growth for optimized sector magnet bending.