Takashi Kosuge

A soft X-ray (80–1500 eV) grazing-incidence monochromator with varied-line-spacing plane gratings at PF-BL-11A

The design and performance of a new soft X-ray beamline BL-11A at the Photon Factory (PF) are presented. A Hettrick-type grazing-incidence monochromator equipped with three varied-line-spacing plane gratings was designed and constructed at a bending-magnet source of the PF 2.5 GeV storage ring. An 800 lines mm(-1) laminar grating produced by aspheric-wavefront holographic recording optics, as well as a mechanically ruled blazed one, were tested. A resolving power of more than 4500 was achieved at 400 eV with either grating, and approximately 10(10) photons s(-1) are available at a resolving power of 2000. High photon flux enables low-concentration samples, such as surface adsorbates, to be studied. A simple scanning mechanism for a wide energy range is quite useful for EXAFS measurements on light elements such as C, N and O.

Commissioning of a Soft X‐ray Beamline PF‐BL‐16A with a Variable‐Included‐Angle Varied‐Line‐Spacing Grating Monochromator

The design and commissioning of a new soft X‐ray beamline, BL‐16A, at the Photon Factory is presented. The beamline consists of a pre‐focusing mirror, an entrance slit, a variable‐included‐angle varied‐line‐spacing plane grating monochromator, and a post‐focusing system as usual, and provides circularly and linearly polarized soft X rays in the energy range 200–1500 eV with an APPLE‐II type undulator. The commissioning procedure for the beamline optics is described in detail, especially the check of the focal position for the zero‐th order and diffracted X rays.

Secure UNIX socket based controlling system for high throughput protein crystallography experiments

A control system for high-throughput protein crystallography experiments has been developed based on a multilevel secure (SSL v2/v3) UNIX socket under the Linux operating system. Main features of protein crystallography experiments (purification, crystallization, loop preparation, data collecting, data processing) are dealt with by the software. All information necessary to perform protein crystallography experiments is stored (except raw X-ray data, that are stored in Network File Server) in a relational database (MySQL). The system consists of several servers and clients. TCP/IP secure UNIX sockets with four predefined behaviors [(a) listening to a request followed by a reply, (b) sending a request and waiting for a reply, (c) listening to a broadcast message, and (d) sending a broadcast message] support communications between all servers and clients allowing one to control experiments, view data, edit experimental conditions and perform data processing remotely. The usage of the interface software is well suited for developing well organized control software with a hierarchical structure of different software units (Gaponov et al., 1998), which will pass and receive different types of information. All communication is divided into two parts: low and top levels. Large and complicated control tasks are split into several smaller ones, which can be processed by control clients independently. For communicating with experimental equipment (beamline optical elements, robots, and specialized experimental equipment etc.), the STARS server, developed at the Photon Factory, is used (Kosuge et al., 2002). The STARS server allows any application with an open socket to be connected with any other clients that control experimental equipment. Majority of the source code is written in C/C++. GUI modules of the system were built mainly using Glade user interface builder for GTK+ and Gnome under Red Hat Linux 7.1 operating system.

Newly designed double surface bimorph mirror for BL-15A of the photon factory

BL-15A is a new x-ray undulator beamline at the Photon Factory. It will be dedicated to two independent research activities, simultaneous XAFS/XRF/XRD experiments, and SAXS/WAXS/GI-SAXS studies. In order to supply a choice of micro-focus, low-divergence and collimated beams, a double surface bimorph mirror was recently developed. To achieve further mirror surface optimization, the pencil beam scanning method was applied for “in-situ” beam inspection and the Inverse Matrix method was used for determination of optimal voltages on the piezoelectric actuators. The corrected beam profiles at every focal spot gave good agreement with the theoretical values and the resultant beam performance is promising for both techniques. Quick and stable switching between highly focused and intense collimated beams was established using this new mirror with the simple motorized stages.

Development and Application of the STARS‐based Beamline Control System at the Photon Factory

STARS[1–2] (Simple Transmission and Retrieval System) is a message transferring software for small‐scale control systems with TCP/IP sockets, originally developed at the Photon Factory (PF). Because it has a server‐client architecture using TCP/IP sockets and can work on various types of operating systems, the design and application are quite flexible. We have developed a common low‐level beamline control system based on the STARS technology. Many kinds of useful STARS clients (device drivers, data acquisitions, user interfaces etc.) are available now, and so far, the system has been installed at 22 PF beamlines. We will describe the development and generalize of the STARS‐based beamline control system at the PF.

Improvement and Upgrade of Small-Angle X-ray Scattering Beamlines at the Photon Factory

Three small-angle X-ray scattering (SAXS) beamlines, BL-6A, BL-10C and new BL-15A2 are available at the Japanese synchrotron facility, Photon Factory (PF). We are recently improving and upgrading the SAXS beamlines at the PF in order to support new measurements and construct a high-throughput experimental system. BL-6A is a bending magnet beamline and the wavelength is fixed at 1.5 angstrom. This beamline had two detectors, PILAUS 300K (Dectris) for SAXS/GI-SAXS and PILATUS 100K (Dectris) for WAXD experiment, respectively, and the simultaneous measurement using these detectors are available. We installed a new experimental stage and replaced PILATUS 300K with PILATUS3 1M in this March. Therefore, the range of an applicable camera length spread to 0.25 ~ 2.5 m, and the detectable angle area expanded in the small-angle region. BL-10A is also a bending magnet beamline and the wavelength has been fixed at 1.488 angstrom. We replaced almost all the optical and experimental components of this beamline with new ones in this March. A fixed-exit double-crystal monochromator, a focusing mirror and a mirror bender were newly installed in this beamline. We will be able to change the energy from 6 to 14 keV. Although the photon flux at the sample position will not change after this upgrade, the area of the beam at the focal point will decrease to 40 % on the basis of the raytracing calculation. The camera length spread from 2 m to 3m in a new experimental stage with the camera tube. PILATUS3 2M and 200K (Dectris) were also installed as a detector. The commissioning will be started from this May, and the beamline will be re-opened from this June. In order to control all new devices and make the user-operation easier, we newly developed GUI software for the beamline control and the experiment. We are also developing the solution sample mixer and changer at BL-15A2 for the high-throughput Bio-SAXS measurement. We will present the current status of these beamline refurbishment.

Integrated Controlling System and Unified Database for High Throughput Protein Crystallography Experiments

An integrated controlling system and a unified database for high throughput protein crystallography experiments have been developed. Main features of protein crystallography experiments (purification, crystallization, crystal harvesting, data collection, data processing) were integrated into the software under development. All information necessary to perform protein crystallography experiments is stored (except raw X‐ray data that are stored in a central data server) in a MySQL relational database. The database contains four mutually linked hierarchical trees describing protein crystals, data collection of protein crystal and experimental data processing. A database editor was designed and developed. The editor supports basic database functions to view, create, modify and delete user records in the database. Two search engines were realized: direct search of necessary information in the database and object oriented search. The system is based on TCP/IP secure UNIX sockets with four predefined sending and...