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The Taiwan Photon Source (TPS) has been successfully commissioned. However, the minimum emittance in the TPS lattice is 1.6 nm rad. In the existing TPS storage ring lattice, it is imperative to reduce the emittance to below 1 nm rad. Therefore, a feasibility study for reducing the effective emittance of the TPS storage ring by using a Robinson wiggler was launched; the reduction is necessary to enhance the photon brilliance. In this study, a permanent-magnet multiperiod Robinson wiggler (MRW) was developed for use instead of the single-period Robinson wiggler. In general, the quadruple field of a combined function magnet in the storage ring is approximately few tesla per meter. According to beam dynamic analysis, we found that it is necessary to adopt a high gradient (40 T/m) combined-function MRW magnet to reduce the emittance effectively. Therefore, a high gradient field strength is required in the combined function MRW magnet. In this study, the quadrupole field strength of the MRW magnet was allowed to be approximately 40T/m at a magnet gap of 20 mm. The period length of the MRW magnet was 300 mm and the period number was 16. The of MRWs is discussed in regard to the possibility of increasing the photon brilliance from IU22. [ABSTRACT FROM AUTHOR]

A prototype superconducting undulator with a 1-m magnet array, a magnet period of 15 mm and a magnet gap of 5.6 mm was fabricated to test the performance of the magnetic field and to investigate related issues. The mechanical precision of the entire iron pole construction is within 30 μm. The electric insulation was enhanced with Kapton tape on the entire magnet array between the wire and the iron. A dummy beam duct was assembled with the magnet array and tested in the test dewar. A cryogenic Hall-probe measurement system with a rail guider was assembled with the test dewar to measure the on-axis field distribution. A UHV beam duct was developed and tested in a separate environment to ensure the reliability and to test the aging effect. In this paper, the concept of the magnet design, the related technical issues, the performance of the magnetic field and the magnet training behavior is discussed. [ABSTRACT FROM AUTHOR]

A continuous spectrum of synchrotron radiation in the hard x-ray region, 5–20 keV, is necessary for the special demand of users, but the high radiation power in that continuous spectrum adversely affects the design of optical components in the beam line. A compromise between photon flux and radiation power of insertion devices should hence be considered. An algorithm and code for spectrum optimization was hence developed using program Mathematica. A wiggler-like undulator with a continuous spectrum was investigated with this code. An optimization algorithm for continuous spectra in the energy range 5–20 keV is presented, and features of the wiggler-like undulator with a continuous spectrum are discussed herein. [ABSTRACT FROM AUTHOR]

A superconducting wavelength shifter (SWLS) with a magnetic field of 6.5 T in cryogen-free operation provides X-rays for high-resolution X-ray microscopy, EXAFS, and medical imaging beamlines. A 32-pole superconducting wiggler (SW) with a period of 6.1 cm and a magnetic field of 3.2 T in a liquid helium bath provides for three dedicated protein crystallography beamlines. Additionally, three 16-pole in-achromatic superconducting wigglers (IASW) with a period of 6.1 cm and a field strength of 3.1 T were constructed in-house and installed between the first and second bending magnets of a TBA arc section. Development of a prototype superconducting undulator (SU15) with a period of 15 mm and a field strength of 1.4 T is currently underway at National Synchrotron Radiation Research Center (MSRRC). © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A mini-pole superconducting undulator with a 15mm period length (SU15) was developed at the National Synchrotron Radiation Research Center (NSRRC). The coil was wound by a superconducting (SC) NbTi wire with small dimensions and low Cu/SC ratio. The design field strength of SU15 with 158turns/pole was 1.4T at 215A, and the magnet gap was 5.6 mm. Extra trim coils and poles are mounted on the main iron pole. The trim coils directly compensate for the strength error of the peak field. The prototype racetrack iron pole was fabricated via electric discharge machining to produce a complete set of 40-poles. The coil was impregnated by epoxy and wrapped in Kapton to maintain insulation between coil and iron pole. A substitution beam duct was built and assembled with the magnet array and tested in the test Dewar. The conceptual design of bath liquid helium (LHe) cryostat has to tolerate more image current and radiation heating on the beam duct. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In response to the growing demand for X-ray research, and to satisfy future needs for generating circularly polarized synchrotron radiation in the X-ray region, a 3.5 T superconducting multipole with a periodic length of 6 cm was designed to produce horizontal linearly polarized, and circularly polarized light on a 1.5 GeV electron storage ring. Differently arranged excitation current loop for the same coil design switched between the operation of symmetric and asymmetric modes to creat the linearly and circularly polarized light, respectively. This study elucidates the design concepts of the superconducting multipole wiggler with symmetric and asymmetric operation modes. The design of the magnetic circuit and the field calculation are also discussed. Meanwhile, the spectra characteristics of the symmetric and asymmetric modes are calculated and presented in this article. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

During the last two years, a series of beam parameters measurement, subsystem checkout, installation of various sensors, control program modification and hardware upgrade made the top-up injection possible in practical routine operation. Top-up injection is an operation mode in which the beam current in the storage ring is maintained above certain level by frequent injections. The routine current stability is in the range of 10-3 for long period of operation. The Top-up injection provides advantages in operation such as lower emittance, higher current, smaller coupling, smaller ID gaps, exotic bunch filling patterns, and higher bunch charge. It also provides constant thermal loading on all components in the storage ring and the optics components of beamlines, as well as constant signal to the beam position monitor. Discussions on the results of some measurements of booster and storage ring, the requirement of hardware upgrade and the summary of routine Top-up operation will be presented in this paper. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]