Bent Crystal Monochromator with Constant Crystal Center Position and 2-theta Arm for a Dispersive Beamline
- Laboratorio Nacional de Luz Sincrotron, LNLS - Campinas (Brazil)
For the new LNLS dispersive beam line it was designed a single-crystal monochromator and a 2-theta arm. The monochromator uses a new bender design assembled on the top of an in-vacuum HUBER goniometer. This bender is able to apply independent torque on each extremity of the crystal in a way that changes in the curvature radius do not affect the position of the center of the crystal. It also has a twist mechanism, based on eccentric bearings and elastic components. The crystal extremities are clamped to the bender using two water-cooled copper blocks, for thermal stabilization. All the bender's movements are done with vacuum compatible stepping-motors. The vacuum chamber was built with enough space to allow future installation of another bender for crystals with different Bragg planes. The internal mechanics is isolated from the vacuum chamber and can move up and down with three high precision jacks. The design of the 2-theta arm is based on two linear translation stages and some special bearings. The two stages are equipped with linear encoders, ball screws end linear bearings. With a proper alignment procedure, it is possible to find the equations that controls each translation stage in order to get a virtual rotation referenced to the monochromator center. The main arm is composed of a steel frame, a 3m long granite block, a central aluminum optical rail and two auxiliary side rails.
- OSTI ID:
- 20653031
- Journal Information:
- AIP Conference Proceedings, Vol. 705, Issue 1; Conference: 8. international conference on synchrotron radiation instrumentation, San Francisco, CA (United States), 25-29 Aug 2003; Other Information: DOI: 10.1063/1.1757879; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Development of a monochromator system for the APS X-ray BESSRC beamlines
Multipurpose monochromator for the Basic Energy Science Synchrotron Radiation Center Collaborative Access Team beamlines at the Advanced Photon Source x-ray facility