[en] The wide use of CAMAC systems in the Large Aperture Solenoid Spectrometer facility led to the design of several dedicated CAMAC interfaces. The one described here features the implementation of bidirectional data transfers, and is used exclusively with the SLAC crate controller, 135-279. Efforts were made to ensure maximum versatility for acquisition of high-energy physics data. Specifications are set forth, and hardware and software (memory address register, word count register, data buffer register, and high-byte register) are described. 4 figures

[en] The 3081/E project was formed to prepare a much improved IBM mainframe emulator for the future. Its design is based on a large amount of experience in using the 168/E processor to increase available CPU power in both online and offline environments. The processor will be at least equal to the execution speed of a 370/168 and up to 1.5 times faster for heavy floating point code. A single processor will thus be at least four times more powerful than the VAX 11/780, and five processors on a system would equal at least the performance of the IBM 3081K. With its large memory space and simple but flexible high speed interface, the 3081/E is well suited for the online and offline needs of high energy physics in the future

[en] A new hardware has been developed to measure the trajectory of microbunches along the Stanford Linac. To be suitable for the operation of the SLAC Single Pass Collider, the bunches absolute position must be kept within +-100 microns of the accelerator center, and the acquisition of this measurement must be made along the machine in a snapshot fashion. Typically, the position of three bunches will be monitored during subsequent shots; we expect a minimum charge of 10⁹ particles per bunch and a time spacing between bunches of 50 nanoseconds. The mechanics of the position detectors is described as well as the general system organization and the calibration of various components

[en] A system has been developed, the primary function of which is to continually display the position, shape, and intensity of the charged particle beam being delivered to the experiment. The system is modular for easy maintenance and is a stand-alone device independent of any computer. (orig.)

[en] We formulate the multibunch feedback problem as a standard control-systems design problem and solve it using Linear Quadratic Gaussian (LQG) regulator theory. Use of a specific optimality criterion allows quantitative evaluation of different controllers and leads to the design of optimal LQG controllers. Computer simulations are used to show that, as compared to the existing Finite Impulse Response (FIR) control, LQG control can provide the same closed-loop damping for less peak power, thus making more effective use of limited kicker power. Furthermore, LQG control enables us to use more power to provide better damping without the problem of driving instabilities with higher loop gains. The code for the LQG filters described has been written for the Quick prototype installed at ALS

[en] We have developed an inexpensive sonar-based instrument to provide a routine on-line monitor of the composition and stability of several gas mixtures having application in a Cherenkov Ring Imaging Detector. The instrument is capable of detecting small (<1%) fluctuations in the relative concentration of the constituent gases and, in contrast with some other gas analysis techniques, lends itself well to complete automation. (orig.)

[en] The design of a FASTBUS interface to the 3081/E is presented. The interface consists of two boards, one specific to FASTBUS, the other usable by other interfaces to the 3081/E. The FASTBUS board is a dual-ported slave, permitting access from either of two cable segments. The general purpose board supports transfers to and from 3081/E memory and provides control of program execution. It also has several features which facilitate software debugging

[en] Since the introduction of the 168/_E, emulating processors have been successful over an amazingly wide range of applications. This paper will describe a second generation processor, the 3081/_E. This new processor, which is being developed as a collaboration between SLAC and CERN, goes beyond just fixing the obvious faults of the 168/_E. Not only will the 3081/_E have much more memory space, incorporate many more IBM instructions, and have much more memory space, incorporate many more IBM instructions, and have full double precision floating point arithmetic, but it will also have faster execution times and be much simpler to build, debug, and maintain. The simple interface and reasonable cost of the 168/_E will be maintained for the 3081/_E

[en] The next generation of synchrotron light sources and particle accelerators will require active feedback systems to control multi-bunch instabilities. Stabilizing hundreds or thousands of potentially unstable modes in these accelerator designs presents many technical challenges. Feedback systems to stabilize coupled-bunch instabilities may be understood in the frequency domain (mode-based feedback) or in the time domain (bunch-by-bunch feedback). In both approaches an external amplifier system is used to create damping fields that prevent coupled-bunch oscillations from growing without bound. The system requirements for transverse (betatron) and longitudinal (synchrotron) feedback are presented, and possible implementation options developed. Feedback system designs based on digital signal-processing techniques are described. Experimental results are shown from a synchrotron oscillation damper in the SSRL/SLAC storage ring SPEAR that uses digital signal-processing techniques

[en] A new hardware has been developed to measure the trajectory of microbunches along the Stanford Linac. To be suitable for the operation of the SLAC Single Pass Collider, the bunches' absolute position must be kept within + or - 100 microns of the accelerator center, and the acquisition of this measurement must be made along the machine in a snapshot fashion. Typically, the position of three bunches will be monitored during subsequent shots; the authors expect a minimum charge of 10⁹ particles per bunch and a time spacing between bunches of 50 nanoseconds. The mechanics of the position detectors is described as well as the general system organization and the calibration of various components