Beamline Control System Research Articles

SPring-8 beamline control system.

The SPring-8 beamline control system is now taking part in the control of the insertion device (ID), front end, beam transportation channel and all interlock systems of the beamline: it will supply a highly standardized environment of apparatus control for collaborative researchers. In particular, ID operation is very important in a third-generation synchrotron light source facility. It is also very important to consider the security system because the ID is part of the storage ring and is therefore governed by the synchrotron ring control system. The progress of computer networking systems and the technology of security control require the development of a highly flexible control system. An interlock system that is independent of the control system has increased the reliability. For the beamline control system the so-called standard model concept has been adopted. VME-bus (VME) is used as the front-end control system and a UNIX workstation as the operator console. CPU boards of the VME-bus are RISC processor-based board computers operated by a LynxOS-based HP-RT real-time operating system. The workstation and the VME are linked to each other by a network, and form the distributed system. The HP 9000/700 series with HP-UX and the HP 9000/743rt series with HP-RT are used. All the controllable apparatus may be operated from any workstation.

Construction of the JAERI soft X-ray beamline for actinide material sciences.

An undulator beamline for spectroscopy studies focusing on the electronic structure of actinide materials is under construction. Linearly or circularly polarized soft X-rays are provided by employing a variably polarizing undulator. Varied-line-spacing plane gratings and a sagittal-focusing system are used to monochromatize the undulator beam, whose energy ranges from 0.3 to 1.5 keV. A resolving power of 10(4) is expected in the whole energy region. These components are methodically operated by the SPring-8 beamline control system. There are three experimental stations in the beamline. In one of the stations the photoemission spectroscopy experiments are carried out at a radioisotope-controlled area where actinide compounds as well as unsealed radioactive materials are usable. Other experimental stations are planned in the beamline for surface photochemical reactions and biological applications.

Modular data acquisition system and its use in gas-filled detector readout at ESRF

Since 1992, 18 ESRF beamlines are open to users. Although the data acquisition requirements vary a lot from one beamline to another, we are trying to implement a modular data acquisition system architecture that would fit with the maximum number of acquisition projects at ESRF. Common to all of these systems are large acquisition memories and the requirement to visualize the data during an acquisition run and to transfer them quickly after the run to safe storage. We developed a general memory API handling the acquisition memory and its organization and another library that provides calls for transferring the data over TCP/IP sockets. Interesting utility programs using these libraries are the ‘online display’ program and the ‘data transfer’ program. The data transfer program as well as an acquisition control program rely on our well-established ‘device server model’, which was originally designed for the machine control system and then successfully reused in beamline control systems. In the second half of this paper, the acquisition system for a 2D gas-filled detector is presented, which is one of the first concrete examples using the proposed modular data acquisition architecture.

Integrating microprobe laboratory automation with high speed data acquisition and analysis

We are developing a laboratory and beam line control system. The MpControl system utilises all the flexibility and power of a computer network. Target stages, power supplies, Faraday cups, beam monitors, event counters, etc. can all be controlled by any of a number of computers in the laboratory. Software on each of these computers allows control, monitoring and display of the state of the beam line, accelerator and target manipulation stage. The entire system may be simultaneously controlled from any computer terminal on the network. The system has the potential to allow a user to manipulate the target stage from the beam control room, or to adjust accelerator parameters from the target chamber at the end of the beam line. The system has been designed to be easily transportable across computer platforms, currently with support for UNIX, X-Windows and MS-DOS. We believe this is a critical factor in a world of rapidly advancing computer and instrumentation hardware systems. The system has been designed to integrate with the MpSys data acquisition system.

The Elettra beam line control system

Elettra is a third generation Synchrotron Light Source located in Trieste (Italy). It consists of a full energy linac injector and a storage ring with beam energies between 1.5 and 2 GeV. The facility is scheduled to be operational by end 1993. For the whole project 22 beam lines from insertion devices are foreseen, each of them is composed of a large number of measurement and controls instruments, most of them embedded in intelligent devices; in addition each beam line can be considered unique compared to the others, having been designed to provide a different kind of synchrotron radiation. This results in a large not homogenous environment where more than 200,000 physical points have to be controlled. A joint team composed of Softeco Sismat and Digital Equipment has developed a fully automated beam line control system able to give full remote controls, with different kind of access rights, to beam line users and beam line specialists as well as a full integration with experiment control systems.

Materials impurity analysis by means of nuclear resonance reactions

An automated beam line for measurement of trace impurities in materials is installed on the FN tandem in the Center for Accelerator Mass Spectrometry, LLNL. The major purpose of the beam-line system is to determine the diffusion of water into glasses by use of the 19F(p, αγ) 16O reaction. This study is stimulated by the radiation-waste-isolation program; however, the system is applicable to studies of other impurities in many material matrices. The target wheels, each of which holds twenty-four samples, can be changed in less than an hour. The beam-line control system both indexes the target wheel and controls the tandem energy as it steps through the requested measurement protocol. The tandem control system, in response to a request, adjusts the terminal potential and other transport elements to maintain constant spot size and location.

Development of centrally controlled synchrotron radiation lithography beamline system

The centrally controlled beamline system for synchrotron radiation lithography has been investigated using the SORTEC storage ring(l GeV). From a practical standpoint, the recently built beamlines aim at attaining a centrally controlled beamline system, which is also serially interfaced with the storage ring. In operating the beamlines, not only local control, but also a central control notion is adopted. The central beamline control system comprises a beamline main computer and a programmable sequence controller (PSC) link. The local beamline control system consists of a PSC, a control panel, and a personal computer. The beamline main computer collects each beamline status datum through the PSC link, receiving the storage ring data from the main computer of the 1 GeV synchrotron radiation (SR) source. A novel oscillating mirror mechanism is proposed, in which the mirror chamber, driven by a combination of a cam mechanism and pulse motor installed in air, is oscillated to scan the mirror, thus producing high reliability and compact design. In addition, a practical beamline structure is offered which fulfills system vacuum protection and protects operators from radiation exposure.

Characteristics and performance of the Los Alamos VUV beamline at the NSLS

We describe the design and performance of the Los Alamos VUV synchrotron radiation beamline, U3C, on the VUV ring of the National Synchrotron Light Source at Brookhaven National Laboratory. The beamline uses separate function optics to collect and focus the horizontally and vertically diverging beam. The monochromator is a grazing incidence Rowland circle instrument of the extended grasshopper design (ERG). A postmonochromator refocusing mirror is used to focus or collimate the diverging beam from the monochromator. The beamline control and diagnostics systems are also discussed. Particular emphasis in the design has been placed on the reduction of stray and harmonic light. Higher order light is reduced by a grazing angle mirror low pass filter installed immediately downstream from the monochromator while stray light is reduced through the use of baffles and thin film filters. Also included in the line is a differential pumping section that permits gas phase and other experiments requiring pressures in the 10 −5 to 10 −4 Torr range to be coupled to the beamline.

LSI-11 Based Auxiliary Crate Controller for Beam Line and Experiment Control

A beam line control system using an Auxiliary Crate Controller incorporating a LSI-11/2 processor has been developed at the Clinton P. Anderson Meson Physics Facility. The LSI-ll runs under the RSX-11S operating system and by means of a specially designed control console allows easy implementation of beam line and experiment controls independent of a larger computer system.