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For the study of high-temperature superconductors and for the application of superconductivity, a superconducting high-field magnetization system with a hybrid superconducting coil was designed. This coil is composed of superconducting wires of three kinds—HTS YBCO 2G-wire, high-field and low-field NbTi wires. Three principal purposes of building this system are to inspect the characteristics of disk-shape bulk YBCO, to develop a HTS-bulk undulator, and to magnetize a portable HTS-bulk high-field magnet for application to a resonant X-ray scattering experiment. With four steps of temperature decrease, a two-stage GM-type cryocooler and liquid nitrogen provide cooling for the magnetization system. The hybrid superconducting coil, two cryogenic systems for the magnetization system and the portable HTS-bulk magnet, and the control and monitor systems that were designed are discussed. [ABSTRACT FROM PUBLISHER]

In material research, the characteristics of novel materials vary greatly with the environment. A magnet with a strong field will be developed for an experimental station for resonant X-ray scattering to investigate the magnetic properties of materials. This magnet will be developed with high-temperature superconductor (HTS) bulk YBa2Cu3O7 and magnetized with a HTS coil magnet wound with 2G HTS wire. HTS (RE) BCO will be selected to construct the coil of this magnet. Both the bulk and coil magnets will be assembled on the same movable system. The bulk HTS magnet will provide flux density greater than 4 T with a gap 34 mm that can accommodate the sample holder of the experimental station. The bulk magnet will be cooled with cryocoolers to 29 K and the coil magnet to 4.2 K; the coil magnet is separable from the bulk magnet after the field is trapped. We describe the concept of the magnetic-field calculation, the overall design of these magnets, and the cooling algorithm for the bulk HTS magnet system. [ABSTRACT FROM AUTHOR]

A prototype of an Apple-II elliptically polarized undulator (EPU4.6), of length 0.46 m, has been constructed to test the performance of the newly designed magnet block, which was magnetized at a tilt angle 10°. The magnet design and various mechanism analysis are performed to clarify the error source of multipole field components. Good end pole design in the EPU4.6 revealed the variation of the first integral field strength as function of gap and phase is minimized. Shimming algorithm had been used to improve the field quality and phase error. We report here the scheme of the magnetized block arrangement, an analysis of the design mechanism, the end pole design, field shimming and the final test performance using the Hall-probe mapping system. [ABSTRACT FROM AUTHOR]

This study describes the design and testing of a superconducting solenoid magnet for soft X-ray magnetic circular dichroism (SXMCD) experiments at the National Synchrotron Radiation Research Center (NSRRC). The superconducting solenoid magnet provides an uniform field of up to 8 T in a bore of 55 mm in diameter and 0.5 m long. The superconducting solenoid is operated in a 4.5-K liquid helium bath for reducing the vibration level during the experiments. The magnet and its cryostat are optimized to prevent magnet quenching and lower liquid helium consumption. The magnet quench test and magnetic field measurements are also performed. [ABSTRACT FROM AUTHOR]

A cryogen-free cryostat for a superconducting undulator with a period of 15 mm (SU15) was developed at the National Synchrotron Radiation Research Center (NSRRC). A 0.44 mm-thin superconducting NbTi wire was wound on iron pole with a racetrack profile. The design field strength of SU15 was 1.4 T and the coil had 148 turns/pole at 230 A; the magnet gap was 5.6 mm. The liquid helium (LHe) recondensation cryostat was designed for SU15. The cryostat provides the advantage of uniform cooling and reduces the amount of LHe consumed. A 0.3 mm-thick stainless steel (SS) beam duct was formed to separate the vacuum in the storage ring from the magnet. Therefore, all of dirty material is produced out of storage ring vacuum. Most of the heat leaked from the LHe vessel leaks from the LHe-fill port heat leak and the 300 K-4.2 K beam duct or was associated with image current power dissipation (ICPD) and bending magnet power dispersion (BMPD). The leaking of heat from the main coil was prevented by the high-temperature superconducting current leads (HTSC). The beam duct was coated with a copper layer with a high-RRR ratio to reduce image current heating. The heat loads on the magnet were cooled using two 1.5 W Gifford-MacMahon (GM) type cryocoolers via LHe medium. [ABSTRACT FROM AUTHOR]

Mini-pole (short period) in-vacuo superconducting undulators, a vert5ical-winding racetrack coil structure, a horizontal-winding racetrack coil structure and a staggered array structure, were studied for use in the X-ray source in a 1.5 GeV or a medium-energy 3 GeV storage ring. The magnetic arrays are all installed in the ultra-high vacuum environment, required for passing electron beams. In a periodic length of 15 mm and a gap of 5 mm, field strengths of 1.5 T, 1.5 T and 0.7 T can be generated in the three different structures, respectively. Additionally, the staggered undulator with variable-period length or a translator structure with different periodic length can yield various deflection parameters k, by driving a longitudinal solenoid field of 0.8 T. Accordingly, this study addresses the magnet structure of and mechanism of the magnet, and the advantages and disadvantages of the structures of these undulators. The spectral characteristics and the magnetic field features of these undulators are also studied. [ABSTRACT FROM AUTHOR]