A summary of the dynamic behavior of the proton bunches in the Brookhaven Alternating Gradient Synchrotron (AGS) has been given previously. In these reports, the usual linearization of the differential equations involved has been made and the theory was restricted to well bunched beams. The linearized approach is no longer valid at transition where the actual phase angle of the bunch can differ appreciably for a short time from the stable phase angle Φ₀. In this report the non-linearity of the differential equations for phase oscillations will no longer be neglected. At transition the beam is slow enough so that the electronics of the bootstrap system can be considered as being ideal and the radius servo loop can be characterized by one time constant. Under these assumptions the analysis can be carried out in a two-dimensional phase plane. The essential new result will be the short existence of a stable equilibrium point for the bunch motion not coinciding with Φ₀. The results here derived have been tested experimentally and at least a qualitative agreement was found. However, the conclusions are no more valid if debunching takes place since we have still neglected the finite bunch width.

From abstract: "The objective of this program is to make a compilation of neutron capture gamma ray spectra of the naturally occurring elements, covering both the low and high energy region, using Na I(TI) scintillation detectors...During this phase of the program a detection system, together with its associated shielding was constructed and tested."

A system for scintillations from nuclear events has been developed and is presently in use at the Lawrence Radiation Laboratory. This paper primarily describes the pulsed light source used to simulate nuclear events; it also describes the necessary nanosecond pulse techniques to measure the light source parameters and to operate large numbers of lamps. Considerations concerning distribution networks are shown. Use of the light source as a spark gap trigger is also discussed.

Monthly report the progress and development of improved zirconium alloys for service in superheated water and steam. This report covers the period between April 1 to April 31, 1961 and was conducted by the United States and the European Atomic Energy Community (EURATOM).

The structure and operation of cyclotrons are discussed. Factors limiting cyclotron size and energy are given. Improvements to the basic continuous-wave cyclotron are described, including frequency modulation, strong focusing, and variable-energy facilities.

Recent experience in instrumentation of several nuclear-physics experiments has demonstrated the feasibility of automating the data-acquisition phases of the experiment. Electronic circuits are employed wherever the rate of data flow would be slowed by the use of human operations. Information is selected, temporarily stored, and then recorded in a form suitable for immediate entry into a computer. Experimenters thus freed from the tedious aspects of data collection can devote their time to studying the results of the experiments. Potentially useful nuclear events are first selected by the fast-logic part of the instrumentation. Circuits performing simple logical functions are packaged in modular form for easy grouping into particular coincidence, gating, and mixing configurations. Circuits with slower response times are used for temporary storage and recording operations. Automatic test routines are used to initially align the equipment as well as provide continuous calibration during the experiments. Some of the high-speed circuits are described as well as the methods used to incorporate them into a large counting system.

An engineering-scale demonstration of the Sulfex process indicated that semi-continuous decladding of unirradiated stainless steel-clad UO2 or U02ThO2 fuels is feasible.

"The ion source used for hydrogen and deuterium ions in the variable energy cyclotron at the University of Rochester is of the hooded arc type. For the past year it has been operating with a new feature which has greatly improved its performance. The new feature is a magnetic mirror built into the upper end of the arc hood by a simple insertion of a steel bearing ball 1/8" in diameter. The magnetic field gradient near the ball provides a magnetic mirror action on electrons moving up the arc channel toward the ball, reflecting may of them."

Startup accident and pump run-down on the ORR have been simulated on the Reactor Controls Analog Facility. At full flow the 150% level scram (45 Mv) easily terminates the startup accident before the metal temperature gets above 180°F. For very low flows typical of criticality runs, temperature coefficients turn the excursion before it reaches 150% of full power, and temperatures climb to boiling, a potentially hazardous condition. (This same behavior can occur at full flow is the power is increased to the point where the level scram must be set above 50 Mw).