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In order to protect the hardware components of the de-tector and accelerator from sudden beam loss of high beam currents, the fast beam abort system is developed in the SuperKEKB. The previous abort system was not fast enough for sudden beam loss that caused QCS quench, and it gave a damage to the collimator and the Belle-II detector. A fast abort system is required to pre-venting such damage. The abort system consists of sev-eral sensors that generate interlock signal (the loss moni-tor, dose in the Bell-II detector, and the magnet failure etc.), optical cable system to transfer the interlock signal to central control room (CCR), the abort trigger signal generation system and the abort kicker. To reduce total time, we reduce transmission time from local control room to CCR by changing signal cable route. Since the interlock signal produced by magnet power supply was slow, we modified the magnet power supply. For more quick generation of abort trigger signal, we increased number of the abort gap. By these improvements, an average abort time is reduced from 31µsec to 25µsec. This improvement looks small, but it brought preventing the serious radiation damage to many hardware compo-nents. Detail of the system and result is presented in this paper., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

KEKB was upgraded from 2011 over 5 years in order to increase the luminosity and started SuperKEKB commissioning in 2018 after the test operation. In order to cope with large beam currents and small beam sizes, various updates have been applied to the beam instrumentation system. This talk summarizes the performance of beam instrumentation in SuperKEKB Phase-III and challenges to it., Proceedings of the 65th ICFA Advanced Beam Dynamics Workshop on High Luminosity Circular e+e- Colliders, eeFACT2022, Frascati, Italy

We introduce the control system of the SuperKEKB collider which is based on EPICS. We standardize the CPU module so that we easily maintain our huge control system. Most Input/Output Controllers (IOCs) installed along the 3 km beamline at SuperKEKB are developed with only two kinds of CPU module. In addition to providing standard IOC for individual hardware, we develop some beam operation system which promotes the beam commissioning. The alarm monitoring system, abort trigger system, and Beam Gate system are developed by the control group. The sophisticated Beam Gate system for positron beam controls operation of both damping ring and main ring. It obviously promotes the beam commissioning at those rings. The other highlight is the precisely synchronized control system. It is necessary to realize the highly complicated control of beam injection process. We configure the dedicated network with the Event Timing System and the distributed shared memory. The distant hardware components are synchronously operated with this network. The beam commissioning of SuperKEKB has been started in 2016. The control system supports its fruitful beam operation without serious problem., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA

SuperKEKB project aims at world highest luminosity to 8x10³⁵cm⁻²s⁻¹. To achieve the luminosity, a lot of equipment was newly constructed or upgraded. Especially, Damping Ring (DR) was newly constructed for reducing positron emittance, and was located at the middle of the injector LINAC. The DR timing system was also constructed. The synchronized timing which is generated at injector LINAC, is received at DR sub timing station and is distributed the end of some equipment, Kicker, Septum, and monitoring devices. We succeeded to generate not only synchronized timing but also beam control information such as beam gate for trigger inhibit signal and injection and extraction timing "value" via data buffer delivery. By using this method, accelerator operation became more convenient system., Proceedings of the 12th Int. Workshop on Emerging Technologies and Scientific Facilities Controls, PCaPAC2018, Hsinchu, Taiwan

The electron beam pulses of injector linac for the SuperKEKB collider are enabled and disabled by Beam Gate control system. This system controls the delivery of triggers to the electron guns at the injector. Also, the septum and kicker magnets for injection point of main ring are controlled with this Beam Gate to avoid unnecessary operation and to prolong their lifetime. The Beam Gate synchronizes the enabling and disabling operations of these hardware even though they are about 1km distant. Besides, from the phase-2 operation, the kicker and septum magnets for newly constructed damping ring becomes controlled apparatus of this system. We develop the new Beam Gate control system with the Event Timing System network*. The new system improves the unsatisfied performance of Beam Gate in the phase-1 operation and realizes the complicated control for phase-2. The advantages of new system are: the control signal is delivered via Event nettork, so that we do not need to cable new network. The enabling and disabling operations for distant hardware are surely synchronized by the Event Timing System., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

The KEK electron/positron injector chain delivers beams for particle physics and photon science experiments. A damping ring has been constructed at the middle of the linac to generate a positron beam with sufficiently low emittance to support a 40-fold higher luminosity in the SuperKEKB asymmetric collider over the previous project of KEKB, in order to increase our understanding of flavour physics. A timing and control system for the damping ring is under construction to enable the timing synchronization and beam bucket selection between the linac, the positron damping ring and the SuperKEKB main ring. It should manage precise timing down to several picoseconds for the beam energy and bunch compression systems. Besides precise timing controls to receive and transmit positron beams, it has to meet local analysis requirements in order to measure beam properties precisely with changing the RF frequency. It is incorporating the event timing control modules from MRF and SINAP., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

The time synchronization for multi CPU system is always a problem to be worried. The control system of accelerator is no exception since it consists of a lot of CPUs located among large area distantly. The problem appears conspicuously when the beam is aborted. Usually, several hardware show abort signals in one beam abort event. However it is difficult to know which is the source of beam abort and which issues an abort signal under the influence of original failure. We introduce the time synchronization system of the SuperKEKB collider which choose EPICS as the control software. The system utilize Event Timing System and synchronizes the EPICS general time for I/O controllers located distantly. The accuracy of synchronization is around 10ns. It is the excellent performance in terms of synchronization of CPU time. The all abort channels of SuperKEKB are synchronized their issued time. Besides they synchronize with also the injector linac which is operated with the different control system in different network., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The SuperKEKB B-Factory at KEK (Japan), after few years of shutdown for the construction and renovation, has finally come to the Phase-1 commissioning of the LER and HER rings, without the final focus system and the Belle II detector. Vacuum scrubbing, optics tuning and beam related background measurements were performed in this phase. Low emittance tuning techniques have also been applied in order to set up the rings for Phase-2 with colliding beams next year. An update of the final focus system construction, as well as the status of the injection system with the new positron damping ring and high current/low emittance electron gun is also presented., Proceedings of the North American Particle Accelerator Conf., NAPAC2016, Chicago, IL, USA

The beam abort system was installed in KEKB in order to protect the accelerator equipment and the Belle detector, and for radiation safety, from high current beams. For SuperKEKB, the new abort trigger system was developed. It collects more than 130 beam abort request signals and issues the beam abort trigger signal to the abort kickers. The request signals are partially aggregated in local control rooms located along the SuperKEKB ring and finally aggregated in central control room. In order to increase the system reliability, the VME-based module and the O/E module was developed, and all the abort signals between the modules are transmitted as optical signals. The VME-based module aggregates input signals and input signals are OR and latched. The E/O module converts electrical signal from abort request source to optical signal. The system also has the timestamp function to keep track of the abort signal received time. The timestamps are expected to contribute to identify the cause of the beam abort. Based on feasibility tests with a prototype module, the new module design was improved and fixed. This paper describes the details of the new abort trigger system., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

There were more than 2500 magnet power supplies for KEKB storage rings and injection beam transport lines. For the remote control of such a large number of power supplies, the Power Supply Interface Controller Module (PSICM), which is plugged into each power supply, was developed. It has a microprocessor, ARCNET interface, trigger signal input interface, and parallel interface to the power supply. The PSICM is not only an interface card but also controls synchronous operation of the multiple power supplies with an arbitrary tracking curve. For SuperKEKB we have developed the upgraded version of the PSICM. It has the fully backward compatible interface to the power supply. The enhanced features includes high speed ARCNET communication and redundant trigger signals. Towards the phase 1 commissioning of SuperKEKB, the construction of the magnet control system is ongoing. First mass production of 1000 PSICMs has been completed and their installation is in progress. The construction status of the magnet control system is presented in this paper., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

SuperKEKB is the upgrade of KEKB, the asymmetric energy electron-positron collider for the B-factory experiment in Japan. It aims at the 40-times higher luminosity than the world record by KEKB. The KEKB control system has been built based on EPICS at the equipment layer and scripting languages at the operation layer. The SuperKEKB control system continues to employ these frameworks while we implement new features for the successful operation at such a high luminosity. As the commissioning of the SuperKEKB main storage rings is scheduled to start in 2016, the construction of the control system is now in the final phase. We have upgraded and reinforced the network system, server computers and operator consoles. Most of the VME-based IOCs (I/O Controllers), which has been widely used in KEKB, are upgraded while the PLC-based IOCs are also widely introduced. The new timing system has been developed in order to handle the complicated injection scheme of the SuperKEKB accelerator complex efficiently. The new beam abort trigger system and the new beam gate control system have been developed, and so on. The construction status of the SuperKEKB accelerator control system will be presented., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

This presentation will cover the status of the installation and the injector commissioning status of SuperKEKB. The IR optics and design with very low β^{*} of less than 1 mm will be discussed., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

We have upgraded the accelerator control network system for SuperKEKB, the upgrade of the KEKB asymmetric energy e⁺e⁻ collider for the next generation B-factory experiment in Japan. For SuperKEKB, the accelerator control network system with the higher performance of the wider bandwidth data transfer, and more reliable and redundant configuration, is required, to ensure the robust operations under the 40 times higher luminosity. We install the 10 gigabit Ethernet (10GbE) network switches for the wider network bandwidth and optical cables to construct the redundant network. We reconfigure the network design to connect the accelerator control network and the KEK laboratory network to enhance the security. For the beamline construction and the accelerator components maintenance, we install the new wireless network system consists with the Leaky Coaxial (LCX) cable antennas and collinear antennas, which have good radiation hardness of >1MGy, into the 3 km circumference accelerator tunnel. In this paper, we describe the design and current status of the SuperKEKB accelerator control network system., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

In this report, we describe the machine operation in the first 3 months of the Phase 1 commissioning of SuperKEKB. The beam commissioning is smoothly going on. Vacuum scrubbing, the optics corrections and others are described., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea