MIRI telescope simulator (MTS) current status

MTS (MIRI telescope simulator) is the Spanish contribution to the JWST Project. MTS is a part of the Optical Ground Support Equipment (OGSE) for the Assembly Integration and Verification (AIV) and Calibration phase of the MIRI instrument at the RAL (Rutherford Appleton Laboratory) facilities. Briefly, MTS main objetive consists on delivering a diffraction-limited test beam, including the obscuration and mask pattern, to the MIRI instrument that reproduces the output beam of the JWST in environmental conditions similar to those corresponding to the flight. In this work, the current status of the project is reported on. Mainly, after a description of the whole instrument and the optomechanical performances required, the paper will be focused on the current status of the purchase and characterization of certain critical elements belonging to the different subsystems. The first step has been the verification of the thermoelastic behaviour of its structure, employing a mass prototype. Both extensometer measurements and optical measurements with alignment mirror cubes have been carried out during a thermal vacuum test of this MTS prototype. The correlation of the measurements, optically and mechanically, will provide a better knowledge of the structure behavior and will be used to define the integration process.