E. F. Parker

Initial Test of a Proton Radiographic System

Protons have a well defined range in matter. A detector, therefore, placed near the end of range of a monoenergetic proton beam becomes a very sensitive measure of changes in the mass of material which the beam has traversed. This property of protons can be exploited in a variety of ways to make radiographs of solid objects. The experimental radiography system we have built to use with the 200 MeV booster synchrotron of the Zero Gradient Synchrotron (ZGS) is described. In addition, there is a brief description of a more elegant system which would operate with a suitable source such as the proton diagnostic accelerator proposed by R. Martin.

Operating Results and Improvements on the Zero Gradient Synchrotron (ZGS) Polarized Proton Ion Source

The ANL polarized proton ion source has been operating for almost two years. In that time, the improvements and modifications discussed here have increased the peak current by a factor of 3 and the polarization to 75 to 80%. The beam stability and, spin reversal are no longer problems, and the maintenance requirements have been significantly reduced. Some further increases in the output current of the source may be possible. Adding up all of the current gains discussed above and applying them to a well-tuned source with a clean, efficient dissociator tube; beam currents of 50-60 ¿A may be possible. A new RF amplifier and a higher voltage electron gun in the ionizer may allow currents in the 75 iA range. However, beam currents beyond this level will probably require a radically new approach to the design of atomic beam sources.

A High Intensity 1.5 Megavolt Heavy Ion Preaccelerator for Ion Beam Fusion

A preaccelerator is being developed at Argonne National Laboratory (ANL) in a program to demonstrate the accelerator technology which will be needed for power plants utilizing inertial-confinement fusion (ICF). The preaccelerator has been constructed and is now undergoing performance tests with the initial objective of achieving pulsed 30 mA beams of 1.5 MeV Xe+1. The design, construction, and initial performance of the preaccelerator are described.

A New Diagnostic System for Studying the Injector and Injection at the Zero Gradient Synchrotron (ZGS)

The SFC system provides detailed information about the injector beam and the capture and early acceleration cycle of the ZGS more rapidly and accurately than was previously possible. The system was an important part of the retuning program after the titanium vacuum chamber installation. The SFCs a-re frequently employed in maintaining stable ZGS operation with intense beams.

Injection and Acceleration of Protons in the Zero Gradient Synchrotron (ZGS) by Stripping H Ions

The booster injector program for the ZGS requires the stripping of H ions at 50 MeV as the source of protons in the booster accelerator. 1, 2 Using the former Cornell 2. 2 GeV electron synchrotron as a prototype booster, the injection of protons by stripping negative hydrogen ions in a poly-paraxylene thin film has already been demonstrated at the ZGS. 3 A brightness multiplication factor of 100 has been achieved. The limiting factor is the scattering of the circulating protons in the stripping foil.

The Possibility of Acceleration of Polarized Protons in the Brookhaven AGS

The unexpected importance of high energy spin effects and the success of the 12 GeV Argonne ZGS in jumping many intrinsic and imperfection depolarizing resonances suggests that polarized proton acceleration should be tried at higher energy. The 1977 Ann Arbor Workshop concluded that it might be possible to jump depolarizing resonances in strong focusing synchrotrons. During the past year we have evaluated the possibility of accelerating polarized protons in the Brookhaven AGS. We found that for about

High Energy Polarized Deuterons at the Argonne National Laboratory Zero Gradient Synchrotron

2 million one could obtain a polarized ion source, fast resonance jumping magnets, and 3 polarimeters which should allow acceleration of 1011 to 1012 polarized protons to 23 GeV/c with about 70% polarization or to 26 GeV/c with about 50% polarization.

Polarized proton source improvements at the ZGS

Modifications made on the ZGS to allow the acceleration of polarized deuterons and the operational experiences with the first production run with this beam are described.

History of the polarized beam

The final configuration of the Polarized Proton Ion Source used at the Argonne Zero Gradient Synchrotron and the changes to the original configuration are summarized. In particular, we describe the results of cooling the dissociator nozzle to very low temperatures.

New Injection Scheme at the ZGS

In 1973, the first high energy polarized proton beam was developed at the Argonne Zero Gradient Synchrotron (ZGS). It operated very successfully and productively until 1979 when the ZGS was shut down permanently. This report describes the development, characteristics, and operations of this facility.