H.H. Chen

National Synchrotron Radiation Research Center

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F. Y. Lin

National Synchrotron Radiation Research Center

C. S. Hwang

National Yang Ming Chiao Tung University

T.C. Fan

National Synchrotron Radiation Research Center

C.H. Chang

National Synchrotron Radiation Research Center

M. H. Huang

Institute of Modern Physics

C. H. Chang

National Synchrotron Radiation Research Center

Ching-Shiang Hwang

National Synchrotron Radiation Research Center

J. C. Jan

National Synchrotron Radiation Research Center

G. Y. Hsiung

National Synchrotron Radiation Research Center

B. Wang

Ningxia University

Cooperative Institutions

National Synchrotron Radiation Research Center

National Tsing Hua University

National Taiwan University

Wang NMR (United States)

Lawrence Livermore National Security

National Yang Ming Chiao Tung University

Chinese Academy of Sciences

Southern Taiwan Science Park

National Cheng Kung University

Tamkang University

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Eight Tesla Superconducting Solenoid Magnet for the Magnetic Circular Dichroism Study

IEEE Transactions on Applied Superconductivity (2007)

C.H. Chang Ching-Shiang Hwang F. Y. Lin M.H. Huang H.H. Chen

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.

Cryostat

Solenoid

Superconducting wire

Electropermanent magnet

Dipole magnet

10.1109/tasc.2007.897806

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Citations (1)

Design and construction performance of a compact cryogen-free superconducting wavelength shifter

IEEE Transactions on Applied Superconductivity (2002)

Ching-Shiang Hwang B. Wang R. Wahrer H.H. Chen C. H. Chang

A compact cryogen-free superconducting wavelength shifter with a warm bore for electron beam has been constructed for generating synchrotron radiation hard X-rays. This magnet consists of three pairs of racetrack NbTi superconducting coils that can produce a maximum magnetic field of 6.0 Tesla at the central pole. The superconducting coils, the aluminum supporting block, and the return iron yokes are cooled to 4 K, and the thermal shielding and HTS current leads to 60 K, by using a 1.5 W Gifford-McMahon type cryocooler. The technical issues on the magnet design and the construction process are presented. Several different measurement systems are used to characterize the magnetic field performance.

Superconducting electric machine

10.1109/tasc.2002.1018494

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Citations (18)

Analysis of Heat Load in a Superconducting Wiggler With a Semi-Cold UHV Beam Duct

IEEE Transactions on Applied Superconductivity (2006)

H.H. Chen C. S. Hwang C. H. Chang F. Y. Lin S. N. Hsu

A superconducting wiggler with a magnetic period of 6.0 cm (SW6) and a peak field of 3.2 T has been designed and fabricated in the National Synchrotron Radiation Research Center (NSRRC). The beam duct separates the electron beam from the cryogenic system of the magnet. The heat load on the beam duct should be low to stabilize the operation of the superconducting magnets. However, outgassing caused by synchrotron radiation at an electron energy of 1.5 GeV and a current of 200 mA must be reduced. Accordingly, operating the system at a higher temperature can minimize the adsorption of molecules on the beam duct. Therefore, the beam duct system and its connection by finite element analysis are designed to optimize the operating temperature of the beam duct at between 100 and 120 K. Performance of the beam duct is established to comply with specifications during the operation of magnet

Wiggler

10.1109/tasc.2006.871211

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Citations (5)

Design of mechanical structure and cryostat for IASW superconducting wiggler at NSRRC

H.H. Chen C. S. Hwang C.H. Chang J. C. Jan F. Y. Lin

An in-achromatic superconducting wiggler (IASW) was successfully constructed and installed at the Taiwan Light Source (TLS) in January 2006. The cryostat with a 30 L liquid nitrogen aluminum reservoir shielding surrounds the helium vessel, which comprises the cold mass and 100 L liquid helium. The helium vessel is suspended by eight suspension links, which are thermally intercepted at 80 K and can be adjusted by applying tension, such that the center of the cold mass does not move during cooled to 4.2 K. A three-layered stainless tube was designed to prevent the transfer port from freezing and the steam- electricity separation system is designed to supply electricity and return the helium gas to prevent freezing of the power feedthrough.

Cryostat

Wiggler

Feedthrough

Cryogenics

Liquid nitrogen

Achromatic lens

10.1109/pac.2007.4440216

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Citations (5)

Mini-pole Superconducting Undulator for X-Ray Synchrotron Light Source

IEEE Transactions on Applied Superconductivity (2006)

C. S. Hwang J. C. Jan Peihua Lin C.H. Chang M.H. Huang

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/mm ² , 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

Undulator

10.1109/tasc.2006.871236

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Citations (13)

Design and Performance of a New Magnetized Magnet Block on EPU Structure

IEEE Transactions on Applied Superconductivity (2008)

C. S. Hwang Cheng-Hsiang Chang F. Y. Lin Min‐Jie Huang Po‐Hsiung Lin

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.

Undulator

10.1109/tasc.2008.920782

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Citations (1)

Preliminary Test Results Concerning the “Within-Achromat”Superconducting Wiggler at NSRRC

IEEE Transactions on Applied Superconductivity (2006)

C. H. Chang C. S. Hwang H.H. Chen F. Y. Lin M.H. Huang

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

Wiggler

Cryostat

Electromagnet

Achromatic lens

10.1109/tasc.2006.871239

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Citations (4)

Design, Construction, and Performance Testing of a 6.5 T Superconducting Wavelength Shifter

IEEE Transactions on Applied Superconductivity (2007)

C. S. Hwang B. Wang B. Wahrer C. Taylor C. Chen

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.

Cryostat

10.1109/tasc.2007.899830

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Citations (4)

Experimental Demonstration of Negative Capacitance epi-Ge/Si FETs with Ferroelectric Hf-based Oxide Gate Stack for Swing Sub-60mV/dec and Hysteresis-Free

Extended Abstracts of the 2020 International Conference on Solid State Devices and Materials (2016)

M.H. Lee P.G. Chen C. W. Liu K.T. Chen M.-J. Xie

2016 International Conference on Solid State Devices and Materials,Experimental Demonstration of Negative Capacitance epi-Ge/Si FETs with Ferroelectric Hf-based Oxide Gate Stack for Swing Sub-60mV/dec and Hysteresis-Free

Hysteresis

10.7567/ssdm.2016.a-2-01

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Citations (0)

Design of a superconducting multipole Wiggler for synchrotron radiation

IEEE Transactions on Applied Superconductivity (2003)

Ching-Shiang Hwang B. Wang J.Y. Chen R. Wahrer C. H. Chang

A 32-pole superconducting magnet with a 12 /spl times/ 80 mm/sup 2/ cold bore aperture was designed to serve as a multipole wiggler in the Taiwan synchrotron light source. The magnet consists of 32 pairs of racetrack NbTi superconducting coils with a periodic length of 60 mm, and can produce a maximum magnetic field of 3.2 Tesla at a pole gap of 18 mm. The superconducting coils, the aluminum-supporting block, and the return iron yokes are cooled to 4.4 K in LHe bath. The temperature of cold bore beam duct will be at 70 K using liquid nitrogen. Technical issues concerning the design of the magnet and its construction are discussed. A prototype magnet with five poles was also constructed to characterize the magnet design by means of various methods of magnetic field measurement.

Wiggler

Dipole magnet

Aperture (computer memory)

Synchrotron light source

Electromagnet

10.1109/tasc.2003.812634

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Citations (17)