Double Crystal Cryo-cooled Laué Monochromator for use on the I12 JEEP high energy beamline at Diamond Light Source

Authors: Tim Hill (Diamond Light Source) , Adrian Burt (Diamond Light Source) , Thomas Connolley (Diamond Light Source) , Michael Drakopoulos (Diamond Light Source) , John Emmins (Diamond Light Source) , Mark Harman (Diamond Light Source) , Doug Sharp (Diamond Light Source) , Ulrik Pedersen (Diamond Light Source) , Guy Wilkin (Diamond Light Source)
Co-authored by industrial partner: No

Type: Conference Paper
Conference: Fifth International Workshop on Mechanical Engineering Design of Synchrotron Radiation Equipment and Instrumentation (MEDSI)
Peer Reviewed: No

State: Published (Approved)
Published: August 2008

Abstract: The I12, Joint Engineering Environmental Process (JEEP) beamline is designed as a multi-purpose, high energy X-ray beamline providing flexibility in the type and complexity of the experiments it can accommodate. These will include ground breaking experiments to simulate the service conditions experienced by real engineering components, while their internal stress state and structures are continually monitored by the X-ray beam. In order to meet such demanding criteria, a monochromator capable of delivering a large cross section monochromatic beam, up to 100mm wide through an energy range of 50 – 150KeV is required. A cryo-cooled monochromator using a bent Laué-Laué geometry is being designed by the beamline team at Diamond. Of primary importance is the quality of the bend coupled with the thermal management. A typical bend radius of 60m +/-2m over the active area and a heat load of 750 W at 500 mA were specified by the science case. Detailed 3D Analysis of the design was performed combining thermo-mechanical finite element methods in order to see how the crystal would deform under such conditions. As part of the design cycle, the team at Diamond are building a prototype crystal assembly to prove the bending performance and validate the finite element analysis. Using a full field interferometer the surface of the bent crystal can be studied and verified against the perfectly circular geometry required in the Laué condition. Further testing with the monochromatic beam of B16 Optics beamline at Diamond will also be performed prior to final assembly of the I12 monochromator. JEEP is expected to take first light in March 2009 and the monochromator will be installed and operational ready to start taking beam at this time.

Subject Areas: Engineering, Physics, Technique Development

Technical Areas: Controls , Diagnostics , Electrical Engineering , Mechanical Engineering , Optics