Hsu, K. T.

Paper	Title	Page
MOPC071	Development of a High Brightness Photo-Injector for Light Source Research at NSRRC	229
	W. K. Lau, J. H. Chen, C. S. Chou, G.-Y. Hsiung, K. T. Hsu, J.-Y. Hwang, A. P. Lee, C. C. Liang, G.-H. Luo, D.-J. Wang NSRRC, Hsinchu C. H. Chen, N. Y. Huang, Y.-C. Huang, W. K. Luo NTHU, Hsinchu
	A laser driven photo-cathode rf gun system is being installed at NSRRC gun testsite for high brightness electron beam and light source research. The photo-cathode rf gun cavity geometry has been modified from the BNL 1.6-cell structure for 2998 MHz operation. A 798 nm Ti:Saphire laser seeded 3 mJ regenerative amplifier is employed to produce 300 microjoules UV pulses at 266 nm wavelength from a third harmonic generator crystal for emission of photo-electrons from the Cu-cathode in the rf gun. First operation of this system with gaussian laser pulses is scheduled in summer 2008. Future plan for flattop laser pulse operation will be discussed.
TUPC003	Libera Grouping: Reducing the Data Encapsulation Overhead	1041
	A. Bardorfer, T. Karcnik Instrumentation Technologies, Solkan K. T. Hsu NSRRC, Hsinchu
	Libera Brilliance is a precision digital Beam Position Monitor, a building block for modern fast orbit feedback systems. Gigabit Ethernet and UDP/IP protocol are used as a standard data link for real-time beam position signal transmission to the central fast feedback CPU engines. While the UDP/IP over Gigabit Ethernet provides a standardized and proven solution that enables the utilization of COTS components, the UDP and IP protocols are subject to a large data encapsulation overhead, since the beam position data payload is relatively small. To overcome this, several Libera Brilliance units (up to 16) have been grouped together in a redundant private network via the LC optical links and/or copper “Molex” cables. The purpose of the private network is to exchange the data among the Libera Brilliance units without the protocol overhead and send the gathered data via Gigabit Ethernet. Any of the Libera Brilliance units in a group can act as a Gigabit Ethernet group transmitter. The private network is redundant and can survive a single cable failure. The data encapsulation overhead has been significantly reduced. Libera Grouping is being tested at NSRRC, Taiwan.
TUPC038	Filling Pattern Measurement for the Taiwan Light Source	1137
	C. Y. Wu, J. Chen, K. T. Hsu, K. H. Hu, C. H. Kuo NSRRC, Hsinchu
	Filling pattern will affect various operation performance of a synchrotron light source. Measurement of the filling pattern correctly is important. The dedicated filling pattern measurement system has been implemented in 2004 for multi-bunch operation in top-up operation mode. Measurement the purity of an isolated bunch by using time correlated single photon counting method is also addressed. Results are presented in this report.
TUPD007	The Design and Fabrication of the Kicker Power Supply for TPS Project	1446
	C.-S. Fann, K. T. Hsu, S. Y. Hsu, K.-K. Lin, K.-B. Liu, Y.-C. Liu, C. Y. Wu NSRRC, Hsinchu
	The preliminary test results of the kicker power supply for TPS (Taiwan Photon Source) project will be presented in this report. The achieved capability of this test unit demonstrates that it fulfills the design requirement of providing half-sine pulsed current of 2.5 kA (peak), 5.2 s (base-width), with jitter < 1 ns (peak-to-peak). Both units of using thyratron and IGBT switches are built with the same requirements. The technical considerations of both units for this particular application will be discussed.
WEOCG02	Post-mortem Diagnostic for the Taiwan Light Source	1932
	K. H. Hu, J. Chen, P. C. Chiu, K. T. Hsu, S. Y. Hsu, C. H. Kuo, D. Lee, C.-J. Wang, C. Y. Wu NSRRC, Hsinchu
	Analyzing the reasons of various trip events is essential to improve reliability of a synchrotron light source. To identify the causes of trip at Taiwan Light Source (TLS), various diagnostics tool were employed. These diagnostic tools can capture beam trip, interlock signals of superconducting RF system, waveform of the injection kickers, quench and interlock signals of the superconducting insertion device, and instability signals of the stored beam for post-mortem analysis. These diagnostics can be routine monitor signal and record beam trip event. Features of trip diagnostic tools are available now. System configuration experiences will be summarized in this report.
	Slides
WEPC005	Design Considerations of the TPS Linac-to-booster Transfer Line	1989
	H.-P. Chang, H. C. Chao, K. T. Hsu, S. Y. Hsu, D.-G. Huang, C.-C. Kuo, K.-K. Lin, W. T. Liu, Y.-C. Liu NSRRC, Hsinchu
	Design considerations of the linac to booster (LTB) transfer line for Taiwan Photon Source (TPS) project is described in this report. Electron beam from the linac with 150 MeV, 50 π-mm-mrad normalized emittance and 0.5% energy spread will be transferred to a booster synchrotron of 489.6 m. This LTB transfer line is designed with the flexible tuning capability and the diagnostics are included. Matching of transverse beam parameters from linac to booster is deliberated. The on-axis injection scheme with repetition rate around 2 or 3 Hz and efficiency with beta-mismatch for top-up operation is also studied.
WEPC058	Operational Performance of the Taiwan Light Source	2124
	Ch. Wang, H.-P. Chang, J.-C. Chang, J.-R. Chen, F.-T. Chung, F. Z. Hsiao, G.-Y. Hsiung, K. T. Hsu, C. K. Kuan, C.-C. Kuo, K. S. Liang, K.-K. Lin, Y.-H. Lin, K.-B. Liu, Y.-C. Liu, G.-H. Luo, R. J. Sheu, D.-J. Wang, M.-S. Yeh NSRRC, Hsinchu
	The Taiwan light source (TLS) is a 1.5 GeV third generation light source at the National Synchrotron Radiation Research Center (NSRRC) in Taiwan. It has been routinely operated since its opening in 1993. Several major machine upgrade projects have been undertaken and successfully completed in last 5 years, including implementing of digital bunch-by-bunch feedbacks, superconducting accelerating RF cavity, top-up mode injection, etc. The light source now moves forward to its era of mature operation. It delivers more than 5000 hours user time in 2007 with an up-time of more than 98% and a mean time between failures better than 80 hours. Here, we review its annual operational performance with detailed statistics and discuss the possible improvement directions of machine performance.
WEPC082	Technical Considerations of the TPS Linac	2186
	A. P. Lee, H.-P. Chang, J. Chen, C.-S. Fann, K. T. Hsu, S. Y. Hsu, W. K. Lau, K.-K. Lin, K.-B. Liu, Y.-C. Liu, C. Y. Wu NSRRC, Hsinchu
	The technical considerations of the TPS (Taiwan Photon Source) linac will be presented in this report. A 150 MeV turn-key linac is chosen in this case in order to provide the ease of injection into the booster in which the electron energy will be raised up to 3 GeV. This linac will be similar to that equipping at recently commissioned synchrotron light sources. The major beam parameters are derived from the booster and storage ring injection requirements. The beam diagnostics arrangement for linac commissioning purpose will be briefly described.
THPC041	Closed Orbit Correction and Orbit Stabilization Control for TPS Storage Ring	3068
	H.-J. Tsai, H.-P. Chang, H. C. Chao, P. J. Chou, K. T. Hsu, C.-C. Kuo, W. T. Liu, J. W. Tsai NSRRC, Hsinchu
	TPS is a 3 GeV synchrotron storage ring proposed in Taiwan. The designed natural emittance with slightly positive dispersion in the straight sections is less than 2 nm-rad. With 1% emittance coupling, the beam size in horizontal and vertical plane are 120/5 micron in the short straight sections, respectively. The beam position stability requirements are 10% of the beam sizes, i.e., 12/0.5 micron in the horizontal/vertical plane. The closed orbit distortions due to alignment displacement and magnetic field errors are simulated. The distribution of beam position monitors and the location of slow and fast correctors are proposed and the level of achievement is shown.
THPC119	Progress of TLS Fast Orbit Feedback System and Orbit Stability Studies	3260
	C. H. Kuo, J. Chen, P. C. Chiu, K. T. Hsu, K. H. Hu, D. Lee NSRRC, Hsinchu
	The orbit feedback system of the TLS has been deployed for a decade and continuously upgraded. However, due to limitation of the existing hardware, the system cannot remove orbit excursion caused by the perturbation due to fast operation of insertion devices. The newly proposed orbit feedback system with the upgraded digital BPM system and switching corrector power supply system is planned to be installed and commissioned in late 2008. The preliminary calculation on the stability performance for the orbit feedback system is presented in the report. New fast orbit feedback system can be expected to achieve a submicron stability of the electron beam working at a bandwidth of at least 60 Hz.
THPC120	Conceptual Design and Performance Estimation of The TPS Fast Orbit Feedback System	3263
	P. C. Chiu, J. Chen, K. T. Hsu, K. H. Hu, C. H. Kuo NSRRC, Hsinchu
	A 3 GeV Synchrotron (TPS) is proposed in Taiwan. Its storage ring consists of 24 double-bend cells with 6-fold symmetry and the circumference is 518.4m. The report presents the initial design of the fast orbit feedback system (FOFB) for TPS. The system uses 168 BPMs and 168 correct magnets to stabilize global closed orbit at 10 kHz updated rate. The different subsystems are modeled: the BPM systems, the corrector magnet, vacuum chamber, and etc. The latency of the communication and computation is also studied. The preliminary calculation on the stability performance for the orbit feedback system is presented in the report. The FOFB is expected to achieve a submicron stability of the electron beam working at a bandwidth of at least 100 Hz.