R. Sah

The Advanced Light Source

The Advanced Light Source (ALS) is a new synchrotron radiation source which has been proposed by Lawrence Berkeley Laboratory. The ALS will be a key component in a major new research facility, the National Center for Advanced Materials. The ALS will consist of an electron linear accelerator, a booster synchrotron, a 1.3-GeV electron storage ring, and a number of photon beam lines. Most or all photon beam lines will originate from wiggler and undulator magnets placed in the 12 long straight sections of the ALS. A very low electron beam emittance will provide photon beams of unsurpassed spectral brilliance from specially-designed undulators, and a high radiofrequency will produce very short pulse lengths.

Design of a Dedicated Heavy Ion Accelerator for Radiotherapy

A new heavy ion accelerator facility for radiotherapy is being designed at the Lawrence Berkeley Laboratory. Performance requirements have been established. Ions from helium to argon can be accelerated to a maximum energy of 800 MeV/nucleon with intensities in the range 108-109 particles per second. The accelerator subsystems consist of a linac injector, a synchrotron and a beam delivery system. Specifications have been developed for many of the technical components, and some details of the technical design are presented.

Advanced Medical Accelerator Design

This report describes the design of an advanced medical facility dedicated to charged particle radiotherapy and other biomedical applications of relativistic heavy ions. Project status is reviewed and some technical aspects discussed. Clinical standards of reliability are regarded as essential features of this facility. Particular emphasis is therefore placed on the control system and on the use of technology which will maximize operational efficiency. The accelerator will produce a variety of heavy ion beams from helium to argon with intensities sufficient to provide delivered dose rates of several hundred rad/minute over large, uniform fields. The technical components consist of a linac injector with multiple PIG ion sources, a synchrotron and a versatile beam delivery system. An overview is given of both design philosophy and selected accelerator subsystems. Finally, a plan of the facility is described.

A High Performance Control System for a Heavy Ion Medical Accelerator

A high performance control system is being designed as part of a heavy ion medical accelerator. The accelerator will be a synchrotron dedicated to clinical and other biomedical uses of heavy ions, and it will deliver fully stripped ions at energies up to 800 MeV/nucleon. A key element in the design of an accelerator which will operate in a hospital environment is to provide a high performance control system. This control system will provide accelerator modeling to facilitate changes in operating mode, provide automatic beam tuning to simplify accelerator operations, and provide diagnostics to enhance reliability. The control system being designed utilizes many microcomputers operating in parallel to collect and transmit data; complex numerical computations are performed by a powerful minicomputer. In order to provide the maximum operational flexibility, the Medical Accelerator control system will be capable of dealing with pulse-to-pulse changes in beam energy and ion species.

A New High Intensity K-Beam at the Bevatron

A new high-intensity K-beam has been installed at the Bevatron. The design goal was 2.2 x 105 K+ s per machine pulse at 500 MeV/c, 7.4 × 104 stopped K+ s, and less than 106¿ contamination. Large horizontal acceptance (± 210 mrad), short length (~ 10 m) and two stages of separation are the most prominent features of the design. The observed optical properties are in reasonable agreement with the calculations. An evaluation of the performance of this beam is presented.

High Intensity Stopped K-Meson Beam at the Bevatron

A high intensity stopped K-meson beam with a design goal of 105 stopped K+ per pulse is being constructed for the Bevatron. The facility is a large acceptance, 33-ft long beam line, which selects and transports 500 MeV/c Ks to a stopper. The beam consists of a symmetrical arrangement of two large 900 bending magnets, three quadrupoles, and two electrostatic separators. Construction completion of this facility is scheduled for the Fall of 1973.

The PEP Liquid Level System

A liquid level system has been installed in the accelerator housing of the PEP storage ring. This instrument spans the entire 2.2 km circumference of the PEP project, and over one hundred readouts provide reference elevations which are used for the accurate alignment of accelerator components. The liquid level has proven to be extremely precise (± 0.10 mm) and quick to use, and it has contributed to the accurate alignment of PEP before beam turn-on. Since the liquid level readouts are rigidly attached to the accelerator housing, the liquid level has been a convenient means to monitor the settling of the accelerator housing.