Research On The Magnetic Center Measurement Methods For Accelerator Magnetic Components

The magnetic center of the magnetic components is an important basis during the alignment and installation in particle accelerator industry.The efficiency of the ionbeam commissioning operation and the ion-beam quality of the accelerator are directly affected by the accuracy of the measurement data.This paper mainly focuses on three parts: firstly,the magnetic center measurement of small aperture magnetic components;secondly,the magnetic axis deviation angle measurement of the Electron Cooling Device in Spectrometer Ring of national "Twelfth Five-Year" major infrastructure High Intensity heavy-ion Accelerator Facility;and thirdly,the magnetic axis measurement and alignment of the Fourth Generation Electron Cyclotron Resonance Ion Source project of the Institute of Modern Physics,Chinese Academy of Sciences.The research subject selected in this paper has important academic significance and engineering application value.For the small aperture quadrupole magnet,it is difficult to measure the magnetic center with Hall probe maps and rotating coil methods.In this paper,the single stretched wire measurement technology is introduced and a single stretched wire measurement platform is built,and finally the repeatability accuracy of magnetic center offset achieved ±6 μm.Aiming at the precise measurement of the magnetic axis deflection angle of single solenoids in the Electron Cooling Device of HIAF project,an integrated and efficient magnetic axis measurement platform of solenoid was built in this paper by using the scheme of axial Hall and radial Hall rotation measurement.After several rounds of measurement and comprehensive error analysis,the final results show that the accuracy of the measurement platform meets the physical requirement.On this basis,the best manufacturing process of solenoid was picked out successfully and mass production is started.Up to now,this platform has been applied to the batch testing of the magnetic axis deflection of the Electron Cooling solenoids.Aiming at the online magnetic axis measurement and alignment of FECR composite superconducting magnet,in this paper,the rotating coil and rotating Hall combination methods were first adopted interiorly for the magnetic axis measurements of the superconducting sextupole and solenoids.A set of online measurement platform adaptive for cryostat was designed and constructed,which runs steadily after trial installation,and the radial deviation was less than 0.03 mm during a measurement cycle.Because the FECR magnet is not ready at present,the Hybrid superconducting Electron Cyclotron Resonance Ion Source with Advanced design in Lanzhou with similar composition of FECR was selected for online magnetic axis measurement.After several rounds of measurements and data analysis,the measurement result satisfies the physical requirements,which provide a data reference for the operation of HECRAL and a systematic verification for the following magnetic axis measurement and alignment of FECR magnets.In conclusion,in this paper,the verification of measurement methods and the development of measurement system have carried out,which closely combined with the current magnetic center measurement requirements of the accelerator magnetic components.The relevant measurement work carried out in this paper has been conducted through comprehensive data processing and error analysis.Therefore,the measurement results are authentic,and the accuracy of the platform meets the physical requirements.The series of work carried out in this paper not only solves the current testing requirements,but also explores the magnetic center measurement methods suitable for different needs,and summarizes a whole set of data processing process,providing a reference for the diversified magnetic center measurement work of accelerator magnetic components in the future.