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A 3-pole gradient-damping wiggler (GDW) was developed for the ALPHA storage ring at Indiana University. The GDW is effective in modifying the momentum-compaction factor and the damping partition number in the ALPHA storage ring. The yokes of GDW are made by lamination of silicon steel sheets (50CS1300) with a thickness 0.5 mm. Glue (3M 2216) is used to paste the lamination sheets together to create a block using a punch fixture. The C-shape structure and the pole profile of the damping wigglers are cut from the silicon-steel blocks with the wire-cutting machine. One middle pole and two outer poles are assembled on the same girder as the set of GDW. The oblique of pole profile of middle and outer poles is different to obtain the same polarity of gradient field. The magnet gaps of the middle and outer poles are 40 and 35.87 mm; respectively to obtain the same dipole field strength. The field strengths of dipole and gradient-field of the middle (outer) pole are 0.67 T (-0.67 T) and 1.273 T/m (1.273 T/m), by keeping the integral ratio of (dB/dx)/B=1.9\ m^-1 constant. The three combined functions of the dipole magnet can be charged in 1 Hz with a single power supply. There are trim coils on the three poles to adjust the first and second integral fields to zero. The good field region of the middle and outer poles along the transverse x-axis (\DeltaB/B=0.1\%) are \pm50 and \pm40 mm respectively. After fabrication of one set GDW magnet, a Hall probe measurement system was used to measure the magnetic field to verify the design and construction performance of the magnet. [ABSTRACT FROM PUBLISHER]

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 compact three-pole superconducting magnet with an aluminum warm beam duct was designed and fabricated as an X-ray source in a 1.5 GeV Taiwan Light Source (TLS) or the 3 GeV Taiwan Photon Source (TPS). Three pairs of racetrack NbTi superconducting coils were connected to one main power supply to create a central field of over 6.5 T. Two low current trim power supplies were connected in parallel to the two side pairs of the coil to eliminate the first and second field integrals. The wavelength shifter magnet was cooled in a pool boiling helium bath. Helium boils off at 1.3 L/hr. The vapor-cooled current lead is used to pass the 350 A excitation current. The magnetic field strength was measured at room temperature using a Hall probe and a stretched wire system. The magnet was tested successfully to 308 A, at which the central field exceeded 6.5 T, and the peak field on coil was 8.2 T. The design and construction of the magnet and the cryostat, the quenching protection, and field measurement results will be presented and discussed. [ABSTRACT FROM AUTHOR]

A mini-pole planar vertically-wound racetrack coil undulator was studied to determine its potential for use as a hard X-ray source in a 3 GeV storage ring. A field strength of 1.4 T can be obtained for a superconducting undulator with a periodic length of 1.5 cm and a fixed magnetic gap of 5.6 mm. The magnetic circuit was optimized and a current density of 1090 A/mm², at 80% of the critical current, meets the field strength requirement. A prototype with 40 poles was constructed to verify the design of the magnet and the performance of NbTi superconductor. Additionally, the magnetic field shimming method was developed for spectrum shimming. This study discusses the design of the magnetic circuit and the structure of the magnetic array, the field shimming technique, and the test results of the prototype magnet. [ABSTRACT FROM AUTHOR]

A 0.96 m with 16 poles superconducting wiggler is fabricated in-house at NSRRC. The wiggler produced a magnetic field of 3.1 T for a 61 mm period with a pole gap of 19 mm. Three 5-pole prototype magnets using various pole materials from low carbon steel, vanadium permendure steel and holmium are tested and measured to verify the magnetic field performance in the testing dewar. This work describes the design and construction of a magnet and cryostat system. Furthermore, this work presents the results of magnet tests and the field performance of the compact superconducting wiggler. [ABSTRACT FROM AUTHOR]