Abstract: A method of bunch length compression method for a free electron laser (FEL) that avoids parasitic compressions by 1) applying acceleration on the falling portion of the RF waveform, 2) compressing using a positive momentum compaction (R56>0), and 3) compensating for aberration by using nonlinear magnets in the compressor beam line.

Abstract: A method of bunch length compression method for a free electron laser (FEL) that avoids parasitic compressions by 1) applying acceleration on the falling portion of the RF waveform, 2) compressing using a positive momentum compaction (R56>0), and 3) compensating for aberration by using nonlinear magnets in the compressor beam line.

Abstract: A foldable elongate body supporting device comprising an elongate body supporting surface (1) formed of a flexible material and comprising a plurality of linearly aligned support sections (1a) to (1e), each support section having secured on opposed sides a rigid tube (3) extending in the longitudinal direction of the device, the tubes (3) on each side of the sections being axially aligned, a space (4) being formed between each of the aligned tubes and the aligned tube of the adjacent section. A locking member (5) is slidably located in and extending through the aligned tubes on (3) each side of the device, the locking member (5) comprising a plurality of rigid locking tubes (6) each adapted to the movable into a locking position overlapping the spaces (4) between adjacent aligned tubes (3). The locking tubes (6) are joined by hinges (7).

Abstract: An apparatus and method for enhancing pulse contrast ratios for drive lasers and electron accelerators. The invention comprises a mechanical dual-shutter system wherein the shutters are placed sequentially in series in a laser beam path. Each shutter of the dual shutter system has an individually operated trigger for opening and closing the shutter. As the triggers are operated individually, the delay between opening and closing first shutter and opening and closing the second shutter is variable providing for variable differential time windows and enhancement of pulse contrast ratio.

Abstract: A support for suspending reinforcing steel relative to a form wall at a spaced distance is provided. The support includes a vertical member having a first end and a second end, a cantilever support arm extending from the vertical member for supporting a length of reinforcing steel orientated horizontally at a predetermined elevation and at a spaced distance from the form wall, and a clamp means for securing the support to the form wall so that the support arm is perpendicular to the form wall and extends towards the opposite side of the form. A plurality of support arms can be provided for suspending many different lengths of reinforcing steel at different elevations. The support is intended to be used in the construction of reinforcing structures, as for grade beams and is removed from the form wall prior to the pouring of concrete into the form.