METHOD FOR SEPARATING FEL OUTPUT BEAMS FROM LONG WAVELENGTH RADIATION

摘要

A method for improving the output beam quality of a free electron laser (FEL) by reducing the amount of emission at wavelengths longer than the electron pulse length and reducing the amount of edge radiation. A mirror constructed of thermally conductive material and having an aperture therein is placed at an oblique angle with respect to the beam downstream of the bending magnet but before any sensitive use of the FEL beam. The aperture in the mirror is sized to deflect emissions longer than the electron pulse length while having a minor impact on the FEL output beam. A properly sized aperture will enable the FEL radiation, which is coherent and generally at a much shorter wavelength than the bending radiations, to pass through the aperture mirror. The much higher divergence bending radiations will subsequently strike the aperture mirror and be reflected safely out of the way.

主权项

1. A method for improving the quality of the output of a free electron laser (FEL) having a pulse length and a bending magnet in the output beam, comprising:
a. providing a mirror with an aperture therein; b. sizing the aperture to deflect emissions longer than the electron pulse length of the FEL output; and c. inserting the mirror at an oblique angle downstream of the bending magnet but before any sensitive use of the FEL beam.