Search

A project on a 3.0 GeV Siam Photon Source II (SPS-II) has been started. The storage ring of SPS-II was designed to obtain an electron beam with a low-emittance below 1 nm-rad. The SPS-II injector mainly consists of a 150 MeV linac and a full-energy booster synchrotron. The booster synchrotron will be installed in the same tunnel as the storage ring, with a total circumference of 304.829 meters. The proposed lattice of the booster contains 40 modified FODO cells with combined function magnets. This lattice achieves a small beam emittance less than 10 nm-rad at 3 GeV, which can provide a high injection efficiency for top-up operation. The conceptual design for SPS-II booster synchrotron is presented in this work., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

The new light source facility in Thailand, SPS-II, is a ring-based 3 GeV light source with a circumference of approximately 330 m. The target stored beam current is 300 mA with an emittance of below 1.0 nm rad. The injector has been changed from a full energy linac to a booster injector with 150 MeV linac. The main RF frequency has been reconsidered to a low-frequency range at 119 MHz. Low frequency is chosen with the benefit of low RF voltage for a high RF acceptance together with experience with the present ring RF system of 118 MHz. Details of RF frequency consideration will be discussed. The requirements and details of the RF systems in the booster ring and the storage ring will be presented., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

A new THz Coherent Undulator Radiation (THz-CUR) source has been developed to generate intense quasi-monochromatic THz radiation at the Institute of Advanced Energy, Kyoto University. The system consists of a photocathode RF gun, bunch compression chicane, quadrupole magnets, and short planar undulator. The total length of this system is around 5 meters. At present, this compact accelerator has successfully started giving the THz-CUR in the frequency range of 0.16 - 0.65 THz. To investigate the performance of the source, the relationship between the total radiation energy, peak power and power spectrum as a function of bunch charge at the different undulator gaps were measured. The results are reported in the paper., Proceedings of the 38th Int. Free Electron Laser Conf., FEL2017, Santa Fe, NM, USA

A mid-infrared free electron laser (FEL) named KU-FEL has been developed for promoting energy-related research at the Institute of Advanced Energy, Kyoto University.* KU-FEL can cover the wavelength range from 3.6 to 23 micrometers and is routinely operated for internal and external user experiments. Recently a THz Coherent Undulator Radiation (CUR) source using a photocathode RF gun has been developed as an extension of the facility.* As the result of commissioning the experiment, it was confirmed that the CUR source can cover the frequency range from 160 to 550 GHz. Present status of these infrared light sources will be presented., Proceedings of the 38th Int. Free Electron Laser Conf., FEL2017, Santa Fe, NM, USA

In recent years the beam diagnostics and instrumenta-tion of Siam Photon Source (SPS), Thailand synchro-tron radiation facility, have been significantly improved for both the booster synchrotron and the 1.2 GeV stor-age ring. Additional diagnostics have been designed, fabricated, and installed, and the existing systems have been upgraded. This paper describes the current status of the beam diagnostics at SPS, as well as their respec-tive performances. These systems include beam posi-tion monitors (BPMs), a diagnostics beamline, beam loss monitors (BLMs), real-time tune measurement setups, and others. Apart from the instrument hardware, the acquisition electronics along with the processing software have been improved as well. The details of these upgrades are reported herewith., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

Siam Photon Source, the Thailand synchrotron light source, has received several upgrades in recent years. Most important of which are the improvement of the positional stability of the stored electron beam, and the installation of 2 IDs, i.e. a 2.2 T hybrid multipole wiggler and a 6.5 T superconducting wavelength shifter, to extend the available SR spectrum into hard x-ray region. The beam stability improvement was achieved through several activities, including improving the BPM system, upgrading the existing corrector power supplies, and implementing global orbit feedback. The two new IDs provide higher-intensity and higher-energy (up to 25 keV) synchrotron light, which will be utilized for MX, high-energy SAXS, WAXS, XAS, and microtomography. Ongoing machine upgrades include increasing the energy of the booster and transport line to 1.2 GeV for full-energy injection and eventual top-up operation. Utilization of the electron beam is also being explored. A beam test facility, which extracts electron beam in the booster for characterizing high-energy particle sensors, as well as calibrating other beam diagnostic instruments, has been constructed and is now in operation., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The old RF cavity in the storage ring of SIAM Photon Source (SPS), the 1.2 GeV second generation synchrotron light source in Thailand, has been pushed to its maximum capability to compensate electron energy lost in the storage ring. This energy lost is the effect from two additional insertion devices, which have been installed in SPS storage ring during June to August 2013. The new RF system has been planned since 2012, but with some technical and procurement difficulty the new system was successfully commissioning and running in August 2016. The installation, acceptance testing, conditioning and commissioning results of the new RF cavity, RF high power transmitter, and the low level RF system will be presented, Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Optimisation of a particle accelerator with very limited diagnostic system is proved to be very challenging and complicated. Theoretical calculation and perfect machine model never guarantee the best solution in the actual machine. In this work, optimisation of injection system from Low energy Beam Transport line (LBT) to Siam Photon Source (SPS) storage ring and reduction of beam coupling employing Robust Conjugate Direction Search (RCDS) algorithm are demonstrated. New record improvement on injection efficiency and better coupling control will be presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

A new tune measurement system was recently developed and implemented at Siam Photon Source (SPS) for both the booster synchrotron and the 1.2 GeV electron storage ring. A new electronic module was installed at the SPS booster for collecting the turn-by-turn signal generated when the beam is excited with white noise and fast kicker. The beam excitation was carefully studied in order to determine the optimum beam response. With this system we observed the variation of the tune during energy ramping. The measurement provides information needed to optimise the working tune and to keep it constant. At the SPS storage ring, the excitation signal was changed from swept frequency signal to frequency modulation (FM) signal to reduce the measurement time. Details of the instrumentation setup and its performance will be presented in this report., Proceedings of the 4th International Beam Instrumentation Conference, IBIC2015, Melbourne, Australia

A description of the newly re-built beam loss monitor (BLM) system at the Siam Photon Source (SPS) is presented. The original BLM system was designed and installed in the 1.2 GeV SPS storage ring in 2005. The main problems of this system were poor performance due to RF electromagnetic interference and the use of now obsolete data acquisition electronics. The beam loss detector used is a PIN-diode type from Bergoz. The new BLM system has been implemented using low-noise coaxial cable and an acquisition system based on NI-PXI. The hardware and software modifications incorporated into the new BLM system are presented., Proceedings of the 4th International Beam Instrumentation Conference, IBIC2015, Melbourne, Australia

To generate intense and high energy synchrotron radiation at the Siam Photon Source (SPS) 1.2 GeV storage ring, two insertion devices (IDs), namely, a 2.2 T hybrid multipole wiggler (MPW) and a 6.5 T superconducting wavelength shifter (SWLS), have been installed and operated since 2013. The angular kicks due to the nonlinear effects generated by the IDs represented by kick maps were used in our analysis. The optics distortion was compared to the ones obtained from calculation using hard-edge model and measurement results. In order to investigate the effects of IDs on the beam dynamics, Frequency Map Analysis (FMA) was employed. The effects of the IDs and their compensation are presented herewith., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Nonlinear effects of insertion devices were studied for the Siam Photon Source (SPS) storage ring. Despite the fact that shimming technique was used to minimize the nonlinear components of magnetic field integral arising from random errors, the nonlinear dynamics effects still remain. It was found that calculated dynamic field integrals are largest in the 2.2 T Hybrid Multipole Wiggler (MPW). Dynamics effects of insertion devices are attributed to the wiggling trajectory of electron in the region of magnetic field roll-off due to finite pole width. For better and more effective operation of the SPS storage ring, multipole components of the dynamic field integral in the MPW have to be further reduced., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Beam Loss Monitoring (BLM) system is an essential tool for observing beam instabilities and hence for machine protection. At the Siam Photon Source (SPS) storage ring, the BLM system is used to check the beam behavior due to optics perturbation, ion trapping, and vacuum leakage. A network of 50 PIN-diode detectors from Bergoz has been installed around the ring at the positions of high particle density. These positions are at the values of large betatron and dispersion functions in the machine lattice. The operational results of tune scanning verses loss rate in the resonance diagram are described. These results will be useful for improving the beam performance in terms of lifetime and beam stability., Proceedings of the 4th International Beam Instrumentation Conference, IBIC2015, Melbourne, Australia

The SLRI Beam Test Facility (SLRI BTF) is a part of the future upgrades of the SLRI accelerator complex. Upon completion, SLRI BTF will be able to produce electron test beams with the number of electrons ranging from a few to several thousand electrons per bunch. The project is divided into three stages based on the complexity of the electron reduction setups. The simple setup for the initial stage has been implemented without any modifications to the current high-energy beam transport line (HBT) while additional elements together with an existing 4-degree dipole are required for the short-term setup in the second stage. For the last stage, a new dedicated transfer line equipped with a high-resolution energy selector will be constructed to direct the electron beam from the HBT beam line to an experimental station. This project aims to provide a defined number of electrons with maximum energy of 1 GeV for calibration and testing of high energy detectors as well as other beam diagnostic instrumentations., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

A 2.4 T hybrid multipole wiggler (MPW) and a 6.5 T superconducting wavelength shifter (SWLS) have been successfully installed and commissioned at Siam Photon Source (SPS). The influence of the two insertion devices on the electron beam dynamic at different operating points have been studied in order to determine the optimal lattice configuration for operation. In this paper, the compensation of the linear optics will be presented, and the commissioning scheme will also be described. In addition, the investigation of the difference between the model and the actual observed machine parameters will be reported in details., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The Siam Photon Source (SPS) is the 1.2 GeV second generation light source in Thailand. It is managed by the Synchrotron Light Research Institute (SLRI). The institute is located inside the campus of Suranaree University of Technology (SUT), which is approximately 20 km from the city of Nakhon Ratchasima (or normally called Korat). Korat is 250 km north-east of Bangkok. Two insertion devices (IDs) have been installed in the SPS storage ring during June to August 2013. These IDs require additional electrical field energy from RF cavity to compensate electron energy loss in the storage ring. The existing RF cavity has been pushed to its maximum capability and the new RF cavity is in the procurement process. The design and study of the new RF cavity will be presented. Electromagnetic fields of the cavity are studied together with the effects to electron beam instabilities., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany