Search

The Taiwan Photon Source (TPS) is capable of operat-ing in multi-bunch and single-bunch mode. To operate in a hybrid mode as requested by users, we developed a lattice with chromaticities of 0.8/2 (x/y) to provide higher single bunch currents. Beam dynamics simulations and lattice characterizations including dynamic aperture, frequency map analysis, tune shift with energy, tune shift with amplitude, and betatron coupling will be discussed in this report., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

In synchrotron facilities, X-ray beam position monitor (XBPM) is an important detector for photon beam position monitoring and must be calibrated to ensure reliability and precision. However, light source operating conditions, such as beam orbit, injection and insertion device parameters, etc., can influence the sensitivity and specific weighting of photoemission current from the XBPM diamond blades. In the Taiwan Photon Source (TPS), Experimental Physics and Industrial Control System (EPICS) was utilized to implant an automatic calibration process. By using EPICS, we can ensure a seamless integration between the different front ends (FEs) and direct all data stream into a centralized server, creating a distributed XBPM calibration system. The XBPM performance indicators are analyzed to evaluate the validity of calibration parameters by input/ output controller (IOC) in each FE computing system. This paper will discuss the benefits of implanting this distributed control system into a working environment such as the TPS., Proceedings of the 8th International Beam Instrumentation Conference, IBIC2019, Malmö, Sweden

Taiwan Photon Source (TPS) has been operated for several years since it’s first light in December 2014. TPS has achieved reliable routine operation at 500 mA with more than 10 hrs beam lifetime. The dynamic aperture measurements and associated Frequency Map Analyses (FMA) at TPS reveal the beam dynamics behavior with and without insertion devices. A preliminary measurement study by using the turn-by-turn BPMs and comparison with the model simulation results will be presented in this paper., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

We have developed a beam-based alignment procedure for small gap IVUs (In-vacuum undulators) at TPS, which allow us to measure the field center and mechanical canter of IVUs with 0.1 mm accuracy. The measurement method and results are presented in this paper., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

In order to provide short bunch length for picosecond time-resolved experiments and for coherent IR/THz radiation, low momentum compaction factor (alpha) lattices have been commissioned recently at the Taiwan Photon Source (TPS). The momentum compaction can be positive or negative and its value can be reduced by more than two orders of magnitude. In this paper, we discuss variable low alpha lattice optics, its beam dynamics issues, the measured momentum compaction and bunch lengths as well as beam orbit stability issues, etc., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Pulse magnets are used in storage ring injection kickers. The waveform of the the four kickers have strong relation with injection efficiency. A slightly offset of waveform may cause the four kickers mismatched, which would lead to storaged beam loss and decrease injection efficiency. In order to define the peak value and timing of the half-sine waveform which has noises interfering diagnosis, a curve-fitting method was introduced to monitor and fine-tuning the waveform. The waveforms' data are also archived for reference in case of replacing power supplies. By using this method, it helps to retain a consistent injection efficiency after the power supplies maintenance or replacement., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

In order to provide short-pulse radiation for pump-probe experiments and coherent radiation for THz/IR measurements, we develop low alpha lattices to reduce the momentum compaction factor from nominal operation values 2.4*10⁻⁴ to 2.6*10-5 or lower. The corresponding bunch length at 2.8 MV RF voltage and zero current are from 10.78 ps to 3.55 ps or less. In the low alpha operations, the bunch lengthening as a function of bunch current, the orbit drift and noise enhancements as well as rf stability effect are observed. In this report we will present our studies on the lattice design, optics correction, beam parameters measurements and alpha measurements., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

We developed and tested lattice with lower momentum compaction factor (low alpha) in TPS (Taiwan Photon Source) recently. Operating low alpha lattice can provide picosecond bunch length for time-resolved research and coherent IR/THz synchrotron light. The bunch length around 2.5 picosecond rms was measured by a streak camera* in low alpha mode while operating in the routine users mode** it was around 10 picosecond. This paper presents the related processes and measurements., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Failure analysis during TPS users operation is im-portant to improve the performance of the TPS storage ring. In this report, we discuss the particular radiation dose patterns, relevant to different beam trips, and the development of a tool to help us analyse this dose distri-bution. We will use this analysing tool to train our ability for future failure analysis to shorten the time it takes to find the problem., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

An optimized injection efficiency is related to a perfect match between the pulsed magnetic fields in the storage ring and transfer line extraction in the TPS. However, misalignment errors, hardware output errors and leakage fields are unavoidable. We study the influence of injection transients on the stored TPS beam and discuss solutions to compensate these. Related simulations and measurements will be presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The TPS commissioning period is from August 2014 to March 2016. The experience of phase I [1] (bare lattice 2014.8~2015.3) and phase II [2,3] (SRF and insertion devices 2015.9~2016.3) commissioning is overviewed. Taiwan Photon Source (TPS) started user operation in March 2016. The delivery user time reached 3211 hours. The continuous improvements of integrated accelerator performance are described and future developments are discussed., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The Taiwan Photon Source (TPS) is the latest generation of 3 GeV synchrotron light source which subsystem includes magnet, power supply, vacuum, RF system, insertion device, control system, etc. The operating procedures and checking items are complex. To speed up the machine start-up and shut-down procedures, check the system's status, and prevent misoperation, we summarize the procedures for routine operation and develop the integrated control interface, which concentrates most machine information and control functions into a single window. This interface clearly indicates the machine status and improves operational efficiency., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The Taiwan Photon Source (TPS) is a low-emittance 3-GeV light source at Natioal Synchrotron Radiation Research Center (NSRRC). Five in-vacuum undulator beamlines were delivered to users on Sep. 22, 2016. To generate 10 ~ 500 eV photon with variuos polarizations, users proposed a new EPU : EPU200. In this paper, we present the preliminary results of beam dynamics simulation for EPU200., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The 3 GeV Taiwan Photon Source has been routinely operated for public users since September 2016. Orbit reproducibility and stability are critical for the quality of user experiments. Ambient temperature variations and earth tides can cause a change in circumference, changing in turn the beam energy, and orbit drift. Therefore both, orbit correction and rf frequency adjustments are necessary to keep the ring circumference constant. A Fast Orbit Feedback (FOFB) system combined with rf frequency correction deduced from the fast corrector strengths is applied to the FOFB routine. The correlation between the measured frequency variation with ambient temperature and earth tides is also reported in this article., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

A stable, reliable and well-calibrated beam position monitor (BPM) system is essential for the operation of accelerators. At newly constructed Taiwan Photon Source (TPS), it not only helps us to determine the accelerator parameters, such as Twiss parameters and tune, but also to avoid the damage on accelerator instruments caused by high-energy particle beams or radiation. In this study, we demonstrate a new BPM calibration scheme at TPS storage ring. To excite the electron beams inside accelerator beam pipe by one horizontal or vertical corrector magnet, we measure the response of analog-to-digital converter (ADC) of each BPM pick-up electrodes with different lateral positions and beam currents. Depending on the measured ADC responses, we calibrated the beam position monitor system. Simultaneously, because of limited preparation time after every long shutdown, we are looking for a fast algorithm to ensure the measurement could be done easily and finished as quickly as possible., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The Taiwan Photon Source (TPS) has been successfully commissioned and has reached now stable operation. Now, the machine must be turned off routinely for week-ly maintenance. While following standard machine turn-on procedures for now, we have developed an automatic turn-on program to accelerate operation, for automatic system status checks and to prevent human errors. The turn-on program process flow includes: turn-on of the LTB (linac to booster transport line), the BTS (booster to storage ring transport line), the SR (storage ring), the BR (booster ring) power supplies and BR&SR pulsers as well as degaussing magnets, turning on the BR&SR RF sys-tems, activating the linac electron source, opening all insertion device (ID) gaps to their parking positions, set-ting all ID phases to zero, controlling all front ends (FEs) and loading the desired machine lattice. Individual pro-cedures can be executed alone depending on the desired practical situation. Experience so far shows, that it takes about 30 minutes to proceed from tunnel safety search to the injection ready state of the light source, including a 20 minute period for magnet degaussing., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The Taiwan Photon Source is a 3-GeV low emittance synchrotron light machine with circumference of 518.4m. The lattice is with 24-cell DBA structure and emittance is 1.6 nm-rad. During the commissioning in the past year, we employed MATLAB-based high level applications to calibrate the optical functions in three different operation lattice modes. In particular, we used LOCO (Linear Optics from Closed Orbit) to restore the machine optical functions and reduce emittance coupling ratio. The beam-based alignment (BBA) measurements as well as BPM and corrector errors were identified., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

With the beam energy of 1.5 GeV, the storage ring of Taiwan Light Source (TLS) in National Synchrotron Radiation Research Center (NSRRC) has provided research service to users for more than twenty years. It takes a lot of efforts to keep this accelerator reliable and to improve its stability. NSRRC has finished the construction and commissioning of the new 3-GeV accelerator Taiwan Photon Source (TPS) which will be opened to users with limited beam lines in 2016. On the other hand, TLS has 25 beamlines and still serves users very well as being benefited by its mature operation skills and continuous efforts on maintenance and system improvement. Main challenges and corresponding solutions on TLS operation in these recent years t are presented herein, together with the statistics on operation performance., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The storage ring of Taiwan Photon Source (TPS) has eighteen short straight sections (length 7 m) and six long straight sections (length 12 m). In phase I, three elliptically polarized undulators of type APPLE II and seven in-vacuum undulators, which included four in-vacuum undulators and two elliptically polarized undulators in three double mini-βy sections, were installed. Commissioning of the insertion devices began in 2015 November. The influence of insertion devices on the electron beam and the results after compensation are presented. Problems during the commissioning induced by the electron beam and by radiation, and their solutions, are also explained. For insertion devices in phase II and for devices developed in TPS, the preliminary designs are presented herein, to cover from the VUV to the hard X-ray region., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

To acquire precise beam orbits from beam position monitors (BPMs) in storage ring is one of the most significant diagnosis to measure beam parameters. However, the precise spectrum analyses from BPM data acquisitions such as betatron tune, dynamics aperture and frequency map '..etc. that are depended on more accurate discrete Fourier transform (DFT) or the fast Fourier transform (FFT). A method of the fast Fourier transform correction (FFTc) was employed for the more accurate spectrum measurement in Taiwan Photon Source (TPS). We perform the accuracy and error analyses of this method from some spectral lines in two window functions. And the precise spectrum for betatron tune measurements and related results will be presented., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The Taiwan Photon Source (TPS) is a low-emittance 3-GeV light source at Natioal Synchrotron Radiation Research Center, next to the Taiwan Light source (1.5 GeV). On March 26, 2015, the TPS storage ring with two 5-cell PETRA cavities has successfully operated in 100 mA in top-up mode without the installation of insertion devices (IDs). To reach the design goal of 500 mA, the machine was shut down for 5 months to replace PETRA cavitites with superconducting RF (SRF) cavities and to install 10 IDs: 7 in-vacuum undulators (IU) and 3 elliptically polarized undulators (EPU). The commissioning of TPS storage ring with SRF cavities and IDs began in Sep. 2015. In this paper, we present our results and proceedures of ID commissioning., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The traditional alarm systems usually set up/low limit for various signals. When the acquired values exceed the limits, the alarm system would be activated. The proposed system in this article can focus on various possible events with many kinds of signals for response judgments. During alarm calling period, data can also be announced and recorded. The system can also monitor various events according to different time shifts. Integrating LabVIEW, mobile phone, AT-command and Bluetooth communication, the system can handle factory broadcast, sending E-mail and SMS message. The above sound and words messages can be set directly at the home-made software interface. The new intelligent alarm system can eliminate the procedure made by man with the added event recording, system stability improvement and debugging function in wider application fields., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Taiwan Photon Source (TPS), a low emittance 3-GeV third-generation synchrotron light source, began its hardware integration testing, safety checkout and beam commissioning on August 12, 2014 [1]. The booster ring and the storage ring share the same tunnel in a concentric fashion; the booster ring has circumference 496.8 m, the largest among light source facilities in operation. A combined-function FODO lattice is adopted for the booster ring with natural emittance 10 nm-rad. After hardware improvements were completed, the commissioning of the beam in the booster ring began on December 12 and attained the 3-GeV design energy on December 16., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

The oncoming completion of Taiwan Photon Source is closely constructed beside Taiwan Light Source (TLS). Few civil works are continuously under construction. Building the measurement, recording and analysis platform of software and hardware is the one of the main directions of operation group. To diagnose the instability problem of the light source, the external influence must be eliminated. One of the factors causing the instability is the physical vibration. Vibration measurement helps to evaluate if newly installed equipments are suited for adding on or the influence of the earthquake to the stability of TLS and to improve the light source quality for users. Software has been developed to provide assistance to do some preliminary diagnoses at TLS. In this article, some actual cases in routine operation are also presented., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The test results of a dual one-turn coils configuration for Taiwan Light Source (TLS) booster extraction kicker is presented in this report. The achieved capability of the test unit demonstrates that the rise-time of the kicker current pulse has been improved for beam extraction optimization. This improved performance is mainly accomplished by reducing the load inductance effectively with a dual one-turn coils configuration. The measured result of rise-time variation versus the corresponding load inductance change is briefly discussed., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A test unit of a pulse-forming-network (PFN) kicker power supply has been designed and fabricated for Taiwan Photon Source (TPS) beam injection/extraction of the booster ring. In order to fulfill the requirements, the performance of the designed unit has been bench tested and the results are examined for evaluation purpose. The pulse-to-pulse stability and the flattop specifications are specified according to the beam injection/extraction requirements. Effort has been made to enhance the rise/fall time of the delivered pulse current. The engineering evaluation and its possible application for beam diagnostics purpose are briefly discussed., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan