Mitsuhiro Yamaga

Data acquisition system for X-ray free-electron laser experiments at SACLA

We have developed a data acquisition, control, and storage system for user experiments at the X-ray Free Electron Laser facility, SACLA, at the SPring-S site. The system is designed to handle up to 5 Gbps data rate of shot-by-shot data in synchronization with the 60-Hz of beam repetition cycle. The system has been stably operating for the public users experiments since March 2012.

A soft X-ray free-electron laser beamline at SACLA: the light source, photon beamline and experimental station

The status of a soft X-ray free-electron laser beamline at SACLA is reported.

High‐speed classification of coherent X‐ray diffraction patterns on the K computer for high‐resolution single biomolecule imaging

A code with an algorithm for high-speed classification of X-ray diffraction patterns has been developed. Results obtained for a set of 1 × 106 simulated diffraction patterns are also reported.

Control and data acquisition system for X-ray Free-Electron Laser experiments at SACLA

We have developed a data acquisition, control, and storage system for user experiments at the X-ray Free Electron Laser facility, SACLA, at the SPring-S site. The system is designed to handle up to 5 Gbps data rate of shot-by-shot data in synchronization with the 60-Hz of beam repetition cycle. The system has been stably operating for the public users experiments since March 2012.

A photodiode amplifier system for pulse-by-pulse intensity measurement of an x-ray free electron laser.

We have developed a single-shot intensity-measurement system using a silicon positive-intrinsic-negative (PIN) photodiode for x-ray pulses from an x-ray free electron laser. A wide dynamic range (10(3)-10(11) photons/pulse) and long distance signal transmission (>100 m) were required for this measurement system. For this purpose, we developed charge-sensitive and shaping amplifiers, which can process charge pulses with a wide dynamic range and variable durations (ns-μs) and charge levels (pC-μC). Output signals from the amplifiers were transmitted to a data acquisition system through a long cable in the form of a differential signal. The x-ray pulse intensities were calculated from the peak values of the signals by a waveform fitting procedure. This system can measure 10(3)-10(9) photons/pulse of ~10 keV x-rays by direct irradiation of a silicon PIN photodiode, and from 10(7)-10(11) photons/pulse by detecting the x-rays scattered by a diamond film using the silicon PIN photodiode. This system gives a relative accuracy of ~10(-3) with a proper gain setting of the amplifiers for each measurement. Using this system, we succeeded in detecting weak light at the developmental phase of the light source, as well as intense light during lasing of the x-ray free electron laser.

Data Analysis Environment for X-ray Free-Electron Laser Experiments at SACLA

X-ray free-electron lasers (XFELs) with full spatial coherence, extreme brilliance, and ultra-fast pulse duration [1, 2] allow the investigation of complex phenomena in physics, chemistry, and biology with angstrom and femtosecond resolutions. In particular, a concept of “diffraction before destruction” [3] has been demonstrated for serial femtosecond crystallography (SFX) [4, 5] and coherent diffractive imaging (CDI) [6]. Using femto-second XFEL pulses, diffraction data are collected before radiation damage to samples has time to occur. Since samples are exchanged for each XFEL pulse, shot-to-shot data acquisition (DAQ) is mandatory to correlate the recorded data with the sample characteristics. The shot-to-shot DAQ must be synchronized with the repetition rate of the XFEL source, typically several tens to one hundred Hz for the machine based on normal-conducting accelerators. Shot-to-shot recording of XFEL pulse characteristics is also essential because they fluctuate due to the stochastic nature of a self-amplified spontaneous emission (SASE). We must carefully analyze a huge data set taking the fluctuation into account.

Current status and future plan of the soft x-ray beamline at SACLA (Conference Presentation)

SACLA was inaugurated in March 2012 with two beamlines: BL3 for hard X-ray FEL and BL1 for wide range spontaneous emission. To enhance the research opportunities in soft X-ray region, the SCSS test accelerator, which was a prototype linac of SACLA and decommissioned in 2013, was upgraded, relocated to the SACLA undulator hall, and connected to BL1. The commissioning of this upgraded BL1 had been started from September in 2015, and user operation was started from June 2016. Currently, SASE-FEL pulses in the photon energy range of 20 to 150 eV are available and average pulse energy is about 70 μJ at 100 eV. We are developing beam diagnostic systems such as an arrival timing diagnostics between the SXFEL and the synchronized optical laser. We have further upgrade plans of the accelerator and the beamline. In this presentation, I will report the latest status and future upgrade plans of this beamline.

Current status of the EUV/soft x-ray FEL beamline at SACLA(Conference Presentation)

SACLA was inaugurated in March 2012 with two beamlines: BL3 for hard X-ray FEL and BL1 for wide range spontaneous emission. Currently, all user experiments have been performed at BL3 and BL2 that was constructed as the second hard XFEL beamline. To enhance research opportunities with softer X-ray FEL, we decided to relocate the SCSS test accelerator, which was a prototype of SACLA and decommissioned in 2013, to the SACLA undulator hall, to connect to BL1, and to generate EUV and soft X-ray FEL independently of the SACLA linac. In addition, we started commissioning of the upgraded BL1 in September 2015, and successfully observe SASE lasing at a photon energy of 36 eV in October. We are now constructing the end station, and will start commissioning in June 2016. We will install two C-band accelerator units that increase an electron beam energy up to 750 MeV with a photon energy up to 100 eV in the summer of 2016. In this presentation, I will report the latest status of the beamline.

Data acquisition system to handle multiple experiments at the data rate of 12 Gbps at X-ray free-electron laser facility SACLA

In 2014, the control and data acquisition (DAQ) system for user experiments was reorganized at the X-ray free electron laser facility, SACLA. The upgraded DAQ system now supports concurrent experiments on two beamlines. In order to secure data throughput and introduce access restriction, the data stream and control communications are physically separated for each beamline. The system can handle two data streams of as much as 12 Gbps from two concurrent experiments. Because the system is scalable, it is adaptable to the future upgrades of as many as five beamlines.

Development of a DAQ front-end board for X-ray free-electron laser experiments

In this study, we developed a new data acquisition (DAQ) front-end board for X-ray free-electron laser (XFEL) experiments. X-ray imaging detectors are indispensable for X-ray experiments and their performance is being continuously enhanced. Moreover, recently performed experiments have used various types of detectors. Therefore, we propose a DAQ front-end system design that satisfies relatively high data rates and supports a variety of X-ray imaging detector interfaces. The novel detector that is under development at SPring-8 was selected for one of its applications. Because the first phase of the detector adopted a camera link (CL) interface, we developed a DAQ front-end with a CL field-programmable gate array mezzanine card (FMC). The proposed design has a general-purpose input/output interface to receive trigger signals and event-building information for synchronization of equipments. Moreover, bit error checking during data transmission via CL was also implemented. The system was evaluated for operation tests lasting 209 h with a 3.7 Gbps bandwidth. The results showed that the system achieved stable operation, and no errors were found during bitwise checks or with trigger and event-building information processes. The results indicated that using the silicon-on-insulator photon imaging array sensor (SOPHIAS), the DAQ front-end board was sufficiently stable for XFEL experiments.