Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8168459 | Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | 2016 | 7 Pages |
Abstract
Two high accuracy moving wire (MW) measurement systems based on stretched wire technique were built for the European XFEL (XFEL.EU). They were dedicated to monitor, tune and improve the magnetic field integrals properties during the serial production of the undulator segments, phase shifters and air coil correctors for XFEL.EU. For the magnetic tuning of phase shifters and the calibration of the air coils correctors a short portable MW measurement bench was built to measure first field integrals in short devices with magnetic length of less than about 300Â mm and with an ultimate accuracy much better than 1Â GÂ cm (0.001Â TÂ mm). A long MW measurement setup was dedicated to obtain the total first and second field integrals on the 5-meters long undulator segments with accuracy of about 4Â GÂ cm (0.004Â TÂ mm) and 2000Â GÂ cm2 (20Â TÂ mm2) for the 1st and 2nd field integrals, respectively. Using these data a method was developed to compute the proper corrections for the air coils correctors used at both extremities so that zero first and second field integrals for an undulator segment are obtained. It is demonstrated that charging air coils correctors with these corrections results in near zero effect to the electron trajectory in the undulator systems and consequently no negative impact on the self-amplified spontaneous emission (SASE) process should occur.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Instrumentation
Authors
Frederik Wolff-Fabris, Marc Viehweger, Yuhui Li, Joachim Pflüger,