Speaker
Dr
Harry van der Graaf
(NIKHEF)
Description
Raschain alignment system is under development at NIKHEF for the pre-alignment of CLIC. It is a combination of two 3 point alignment systems: RasNik system, consisting of a coded mask illuminated by LED and projected on a CCD through a lens, and RasDif system, where the coded mask & LED are replaced by a laser, and a diffraction plate replaces the lens. Different applications of Raschain are under study: firstly, as a short range alignment system providing a determination of the transverse position of compoments with a precision and accuracy better than 5um rms over 10m; secondly, as a long range alignment system providing a determination of the transverse position of the components with a precision and accuracy better than 5um rms over 200m, and thirdly, combined with elaborated mechanics, allowing the monitoring of the position of the final focus magnets through the detector, to a precision of 5um rms. This paper presents the first prototypes of Raschain alignment system, the test setups and their associated results. In addition, the next steps of validation are introduced: inter-comparison on short range (4m) and long range (140m), as well as the strategy foreseen for their calibration.
Primary author
Dr
Harry van der Graaf
(NIKHEF)
Co-authors
Mr
Aran Alaei
(NIKHEF)
Mr
Bram Bouwens
(NIKHEF)
Mr
Gerrit Brouwer
(NIKHEF)
Dr
Helene Mainaud Durand
(CERN)
Mr
Henk Groenstege
(NIKHEF)
Mr
Joris van Heijningen
(NIKHEF)
Mr
Michail Anastasopoulos
(CERN)
Mr
Niels van Bakel
(NIKHEF)
Mr
Richard Rosing
(NIKHEF)
Mr
Robert Hart
(NIKHEF)
Mr
Vivien Rude
(CERN)