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The electromagnetic interaction of an intense relativistic coasting beam with itself, including the effect of a confining nonperfect vacuum tank, or a quiescent rf cavity, is investigated theoretically. It is shown that the resonances that may occur between harmonics of the particle circulation frequencies and the electromagnetic modes of the cavities can lead to a longitudinal instability of the beam. A criterion for stability of the beam against such longitudinal bunching is obtained as a restriction on the shunt impedance of the rf cavity, or the Q of the vacuum tank. This criterion contains the energy spread and intensity of the coasting beam, as well as the parameters of the accelerator. Numerical examples are given which indicate that in general the resonances with the vacuum tank will not cause instabilities, while those with an rf cavity can be prevented from causing instabilities by choosing the shunt impedance at a sufficiently low but still convenient value.

Modern {beta}-ray spectrometers are based upon the concept, first introduced by Svartholm and Siegbahn in 1946, of focusing in both the radial and vertical directions. The theory of axially symmetric devices has been carefully studied by a large number of workers, culminating in the analysis, in 1956, of Lee-Whiting and Taylor. These last authors calculate aberrations through the sixth order and show that by appropriate choice of the magnetic field a spectrometer can be designed with a relatively large transmission and a high resolution. The acceptable transmission is remarkable because the second-order 'spherical' aberration in the median plane of the image cannot be made to vanish identically, and consequently the design is forced to a tall thin aperture (or a slightly less advantageous short wide aperture) which a priori would seem to imply a low transmission. It is the purpose of this communication to show that if the arbitrary restriction to axially symmetric fields is removed, then both the radial and the vertical contributions to the 'spherical' aberration can be made to vanish in second order. That azimuthally varying field (AVF) afford the freedom to accomplish this end may well be suspected in view of the technological revolution that the …

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Diverse methods proposed for the acceleration of particles by means of collective fields are reviewed. A survey is made of the various currently active experimental programs devoted to investigating collective acceleration, and the present status of the research is briefly noted.

Relationships necessary for ring stability are derived between the self-focusing forces of an electron ring and the magnetic field gradient defocusing forces present near and just subsequent to spillout.

The purpose of this paper is twofold: to introduce the reader to the subject of instabilities exhibited by relativistic particle beams, and to summarize the present state of our knowledge concerning these phenomena. Most of the material in the first part of the paper is not new. It has been known to some specialists for a good many years; what is new is that the problems that can be solved are now of much more interest to the general community of accelerator physicists. Consequently, many accelerator physicists who have not paid much attention to these matters may now want to become informed; it is my hope that this paper will provide an introduction to the field. The second part of the article consists of two sections. The first summarizes the experimental information presently available, with emphasis upon the degree to which it confirms or disagrees with theory. Our current level of understanding is delineated: considering the generality and reliability of the theoretical analysis as well as the degree of experimental confirmation, the author expresses his opinion as to what can be considered relatively well established. The final section contains a discussion of subjects needing further investigation and, consequently, supplements the …

Recently a number of authors have suggested modifications of the Brueckner theory of nuclear matter so as to include hole-hole interactions, as well as particle-particle interactions. Iwamoto has demonstrated that in a perturbation theory calculation the inclusion of hole-hole interaction makes no change in the ground-state energy through second order. The singular two-body potential between nucleons makes it difficult, however, to conclude anything about the contribution of these terms in nuclear matter. The formal similarity between the equation of Iwamoto and the equation for the energy gap in nuclear matter, coupled with the fact that the energy gap is very small at normal density, indicates that the effect of hole-hole interactions is probably only a very small change in the ground-state energy of nuclear matter. It is the point of this note to show that this conclusion is in fact correct, the demonstration proceeding by use of the separation method for evaluating the energy of nuclear matter.

Radiation damage may occur to the lithium hydride shields as a result of the reaction Li{sup 6}(n, {alpha})H{sup 3}. There is evidence in the literature indicating both the existence and absence of radiation damage to the SNAP shields. It is believed that there is a high probability that there will be damage and that it will adversely affect the properties of the shield. This damage may take the form of: (1) volume expansion of the hybrids, (2) void formation within the hybrids, and (3) gas pressure build-up in the shield container. Based upon the results of experiments with lithium fluoride, which may serve as a model for the hydride, there appears to be a threshold neutron dose which volume expansion effects can not be removed by annealing. Similarly, above the threshold dose, intercrystalline voids, formed as a result of radiation damage, appear to increase in size with increasing temperature. It has been established that at the SNAP shield operating conditions, essentially all of the hydrogen formed will recombine with free lithium. The helium atoms, however, remain trapped interstitially, in intercrystalline voids, or along subgrain boundaries. Appreciable amounts of helium gas are not released until the melting point of the hydride …

As a result of an AEC directive, a review has been made of the disposal of chemicals to the Columbia River by 100-N to determine if any water pollution hazards exist. The search revealed that no chemicals are released continuously in hazardous concentrations; that three cases exist where hazardous concentrations might be released intermittently under worst-case conditions; that two cases exist where intermittent releases result in questionable conditions; and that two cases exist where accidental release from storage might result in hazardous conditions. Recommendations for corrective action are given in all cases.

This document summarizes the amounts of radioactive contamination discharged to ground from chemical separations and laboratory facilities through December, 1964. Detailed data for individual disposal sites are presented on a month-to-month basis for the period of January through December, 1964. Previous publications of this series are listed in the bibliography and may be referred to for specific information on measurements and radioactivity totals prior to December, 1964. Several changes in crib nomenclature were made during 1964. These changes are noted on the individual tables so reference may be made to them in previous reports. Tables I and II list the major disposal sites in the separation facilities, total volume of waste discharged to each location, and the gross amounts of plutonium and beta particle emitters discharged to ground since startup. Tables III through XXIV present this same data on a monthly basis for cribs still in use, and also include information on the source of the waste stream and the settling facility if used. Isotopic data are included for disposal sites from which the waste was analyzed for specific contaminants. Estimates of contamination and volumes discharged to swamps are also included in Tables XXV and XXVI.

The purpose of this report is to permit the charging of the fourth E-N demonstration loading at H Reactor; modifications in the charge makeup and the loading pattern, designed to improve the conversion ratio and to advantageously re-shape the longitudinal flux pattern, are recommended. These gains are available through utilization of the small surplus of excess reactivity, over operating requirements, in the present (third) core.

The original test authorized the irradiation of about 20 fuel columns containing hot-die-sized, diffusion-bonded fuel elements. Objectives of this supplement are to permit irradiation of an additional ten columns of hot-die-sized, diffusion-bonded fuel elements, and to obtain data on the relation of the coolant temperature distribution and fuel element behavior. These fuel columns will be irradiated in smooth-bore Zircaloy-2 process tubes in the C Reactor.

This report details a K area test with the following objectives: find the temperature range within a graphite sample carrier; find the temperature range with a solid graphite bar; find the temperature range with a test hole; determine the temperature difference between the old and new graphite sample boats; compare the temperature of a sample load and a solid bar in the same location; and find the temperature range in which the graphite samples are irradiated in all test holes. Results and conclusions are presented.

This document defines codes which are for use with the data processing program developed for calculating isotopic analyses from raw data out put of a thermal ionization mass spectrometer.

Process and development activities reported include: depleted uranium irradiations, thoria irradiation, and hot die sizing. Reactor engineering activities include: brittle fracture of 190-C tanks, increased graphite temperature limits for the F reactor, VSR channel caulking, K reactor downcomer flow, zircaloy hydriding, and ribbed zircaloy process tubes. Reactor physics activities include: thoria irradiations, E-D irradiations, boiling protection with the high speed scanner, and in-core flux monitoring. Radiological engineering activities include: radiation control, classification, radiation occurrences, effluent activity data, and well car shielding. Process standards are listed, along with audits, and fuel failure experience. Operational physics and process physics studies are presented. Lastly, testing activities are detailed.

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Interchannel flow through fuel element junctions can occur in production reactor fuel columns as a result of different pressure loss patterns in the two coolant subchannels. This interchannel flow is most significant during boiling conditions because, generally, the boiling length in each subchannel is different. These different boiling lengths result in divergent pressure loss characteristics in the subchannels and cause differential pressures to exist across the fuel element junctions. These differential pressures are the predominant driving forces for interchannel flow. The extent to which interchannel flow exists, and its effect on the thermal hydraulic characteristics of reactor flow channels has long been a question of concern in the design of electrically heated models of reactor fuel columns for laboratory experiments. Interchannel flow is quite unpredictable and subject to considerable variation due to mechanical and alignment changes at the junction. It is also very important because it significantly affects the total thermal-hydraulic performance of the fuel column. The purpose of this investigation was to analytically evaluate the effects of interchannel flow on the predicted thermal-hydraulic performance of a production reactor fuel channel and to develop accurate methods by which it could be simulated in electrically heated laboratory models.

Data in this report are significant to Pile Physics calculations and are submitted by the Area Physicists at the respective reactors. Reactivity in non-uranium charges and in radial and spike enrichment is calculated either by one-group diffusion theory or by the simpler flux-squared weighting method. The former method provides a more accurate evaluation for larger enrichment inventories; the latter method is sufficient for radial enrichment of less than about 0.25 percent excess K.

This monthly research and development report details activities of the Irradiation Processing Department for the month of October 1965.

This document provides a method for calculating the compensating effects of horizontal control rods in highly shadowed cases encountered in total control administration. The two-dimensional diffusion theory computer code ``9 ANGIE`` was used to calculate the reactivity effects of the horizontal control rod geometry with respect to total control requirements at B, D, F, and DR Reactors. For total control requirements in the center section of B, D, F, and DR Reactors the horizontal control rods will compensate approximately 25% of the buckling increase presently due to enriched fuel at the top and bottom of the pile. If the enrichment is already compensated by adjacent supplementary poison, the inserted horizontal control rods will reduce the center ``B`` section buckling by an amount equivalent to charging 2 PCCF tubes in the center zone. The direct compensating effect of the horizontal control rods with respect to the enriched fuel on the near side of the ``square pile`` remains unchanged.

This monthly report details the Research and Engineering Section Irradiation Processing Department`s activities for the month of October 1965.

This monthly report details research and engineering operations of the Irradiation Processing Department during the month of July 1965.