Calculations of the photonuclear giant resonance according to the Wilkinson model are presented in this report. In this model the giant resonance in the cross section for absorption of gamma rays by nuclei is ascribed to the excitation of large numbers of nucleons in closed shells. The model generally predicts correctly the integrated cross section for the giant resonance, bu the resonance energy is too low. Results are presented in a series of tables and formulas so that the integrated cross section may be calculated for any given nucleus.

It is shown that under very simple and general assumptions the existence of an antiunitary reflection transformation and the charge gauge group implies the existence of an antiparticle corresponding to a given charged particle. Similar consequences follow on replacing the charge gauge group by the baryon gauge group. No assumptions as to specific wave equations, or indeed the existence of local fields, are made.

This paper discusses a group of high-speed switching circuits using the basic current-switching mode of operation. The first part of the paper presents a dynamic analysis of the basic current-switching mode and the second part is the dynamic and steady-state analysis of a current-switching flip-flop.

The spin of neodymium-141 was measured by the method of atomic beams and found to be 3/2. A lower limit placed on the hyperfine separation of the states with total angular momentum [formula] by second-order perturbation theory shows [formula]. A prerequisite for the determination of the nuclear spin from hyperfine-structure measurements is the knowledge of the electronic structure. The ground-state configuration of neodymium is known and the value is used throughout this work.

Even in its present primitive stage the molecular beam method promises to open up many opportunities for detailed studies of reactive collisions. The early results described here have revealed several features inaccessible to the traditional methods of kinetics. We hope this program of beam studies will ultimately provide the basis for constructing a theory of the molecular mechanics of reactions. By borrowing what are now everyday techniques in nuclear physics (modulation of the beams; mass analysis and counting of detected ions) it appears possible to gain from four to six orders of magnitude.

A displacement of energy levels has been observed in the K=O band of odd-odd deformed nuclei. It is shown that this shift is due to a particular type of scattering in which the final state is obtained from the initial state by a rotation of 180'. This circumstance allows one to state certain selection rules on the parts of the n-p residual interaction responsible for the shift. The Wigner component of the force cannot contribute to the shift. In certain cases the contribution of all central forces will be strongly damped allowing observation of the tensor force scattering contribution. Numerical results are presented.

It is shown that the annihilation rates of positrons in metals can be correlated to a good degree by a simple model of the annihilation process based on an assumption that the fractional number of electrons available for annihilation varies as the inverse of the atomic volume of the metal.

The concept of thermonuclear explosives as a potentially cheap and almost inexhaustible energy source for mankind's non military needs has for several years been under active consideration at the Lawrence Radiation Laboratory. Many of the proposed peaceful applications involve underground nuclear explosions, and several experiments at the AEC Nevada Test Site have provided valuable insight into the phenomenology of such explosions. Among the possible uses currently under consideration are excavation, heat production, isotope production, mining, recovery of oil from shales and tar sands, improvements of ground water supplies, and the construction of earth fill dams. In addition a program of experimental research in the laboratory and in the field is under way. Sometime in 1961 Project Gnome if approved will be conducted in New Mexico. The purpose of Gnome, a contained nuclear explosion in a salt deposit, is to study the feasibility of heat recovery and isotope production, neutron scattering experiments will also be included. Other proposed nuclear projects will involve the creation of a small harbor near Cape Thompson, Alaska as the result of an experiment designed to investigate the cratering effects of nuclear explosives; a proposal to investigate the recovery of oil from Canadian tar sands using thermonuclear …

The wide use of liquid oxygen as an oxidant in rocket engines has resulted in an increased interest in low-temperature heat transfer. Storage tanks for this type of application, being uninsulated, contain a boiling-liquid low-temperature sink, which is susceptible to environmental heat inputs and subsequent liquid loss by vaporization. Such losses are difficult to predict due to the complex combination of ambient conditions which exist, and the lack of knowledge concerning their combined effects. Heat transfer in this field is difficult to analyze primarily because of its transient nature. This is a result of such factors as: (1) the growth of an insulating frost layer on the outer surface of the container, with its accompanying energy transfer to the system; (2) the temperature dependent convective air pattern that surrounds the container, (3) the transfer of radiant energy to the system, and (4) the mechanical failure of the frost itself with subsequent sloughing from the container wall. A lack of knowledge regarding the coefficient of diffusion of water vapor through air and the thermal conductivity of frost in this depressed temperature range further complicates the predictions of heat transfer.

The purpose of Project Cowboy was to investigate the seismic signals generated by chemical explosions in underground cavities, with particular emphasis on the possibility of decoupling of these signals from the surrounding media. The project site was the Carey Salt Company salt mine, located approximately five miles west of Winnfield, Louisiana. The tests were run during fiscal year 1960. This report presents the results of tests performed on specimens from the samples of salt taken in the area.

Abstract. The Equivalence Theorem of P. Lax is extended to difference schemes for initial-value problems for linear inhomogeneous PDE with linear inhomogeneous boundary values and for boundary-value problems.

The following document describes the usage of the LRL 9-ZOOM code, a neutron diffusion theory reactor code for the IBM 709. The code has been modified to solve configuration of a series of stacked cylindrical disks, designating a new geometry case.

This bibliography is selective, unclassified, and covers the period 1950 - April 1960. Sources consulted were the following: Applied Science and Technology Index (Industrial Arts Index), Chemical Abstracts, Engineering Index, U.S. Atomic Energy Commission Nuclear Science Abstract, Armed Services Technical Information Agency Title Announcement Bulletin, and Publisher's Catalogs.

Abstract. The idea of determining potentials from phase shifts is here called the "optical model" while the construction of an effective single particle scattering potential from the known two-body forces is called the "optical potential." A novel method is given for construction of the optical potential with the Pauli principle and its difficulties are pointed out. In the Appendix one connection between the optical potential and optical model is given.

At the Montreal colloquium Ahmed urged Oliver to make batches of emulsion which would differ only in gelatin concentration. At that meeting Oliver had reported finding a correlation between grain size and silver ion concentration during precipitation, as implied by Perfilov and his Leningrad colleagues. Ahmad felt that one should have more precise knowledge of the relative influence of gelatin concentration of grain sized and their distribution. The incentive is that, in spite of excellent progress in many laboratories and in consistently dependable production from industry (to us, of course, Ilford is most familiar), nuclear emulsions are needed in a wider variety of sensitivities and grain sizes. Available nuclear emulsions have limitations in sensitivity, discriminatory ability, and concentration of hydrogen nuclei. Fine grain size enhances discriminatory ability. An incentive is also in that there is a shortage of literature dealing with the processes involved in the fundamental steps of emulsion production.

Abstract. The measured stresses and deflections of cylindrical shells with free ends, when subjected to concentrated loads along the central diameter, are presented. An empirical analog is made with a simply supported flat plate for which stresses and deflection are easy to compute. Over the range of parameters studied (ratio of cylinder diameter to wall thickness varied from 32 to 64, ratio of cylinder length to diameter varied for. 0.6 to 5) the agreement is such that the empirical results should have useful application in the design of shells for local loading.

A technique for measuring extremely small temperature changes by means of a pyroelectric device is described. The sensing element is a short thin rod of polarized barium titanate ceramic with electrodes on the ends. The electric charges produced by changes in temperature are measured by a vibrating-reed electrometer. A number of calorimetric and noncalorimetric applications for the device are suggested.

This report analyzes a linear, hard-core pinch tube built to examine tubes afflicted by small-scale instabilities evident from many observations.

This report describes a toroidal version of the hard-core pinch and the additional information it can obtain to what the analogous linear pinch can get.

Report discussing theories of irreversible thermodynamic processes. "The purpose of this review is to collect the presently available experimental data for a variety of quite different irreversible phenomena and to show that this evidence does indeed verify the Onsager Reciprocal Relations."

An experiment was designed utilizing a charge-exchange reaction to study the decay and interactions of the neutral K mesons produced. The experiment produced no events that could be interpreted as either the decay or interaction of neutral K mesons. The nature of the experiment and the possible explanations of this unexpected result are presented in this paper.

In another paper there was reported an attempt to observe the charge-exchange process in a counter-triggered multiplate cloud chamber at the Bevatron but the interpretation was ambiguous. Shortly after the close of that experiment the 30-in. propane bubble chamber at the Lawrence Radiation Laboratory was completed and able to be used for a combined engineering test and experiment. The existence of Reaction (1) has been confirmed in this experiment, and an approximate cross-section value for carbon is calculated.

Report discussing a system designed to "punch binary data from an RCL pulse-height analyzer (PHA) on paper tape concurrent with the printing of decimal information."

From abstract: "The toxicological properties of beryllium and compounds of beryllium are briefly reviewed, together with the historical development of the recommendations for maximum permissible beryllium air concentrations. The application of the enclosure technique presently in use at this laboratory for the control of beryllium hazards is described... Monitoring procedures used to evaluate the performance of enclosures are discussed."