UNT Libraries Government Documents Department - 550 Matching Results

Search Results

0-2 kv Flash Tube Supplies
In order to perform the various experiments with a bubble chamber, a high intensity flash tube is used. This report briefly describes the power supplies designed and constructed to power these lamps.
6 kv Capacitor Charging Supply
The power supplies designed and constructed to power high intensity flash tubes used in bubble chamber experiments are briefly described and are accompanied by a schematic diagram of the layout. (D.C.W.)
80" Bubble Chamber Expansion System Preliminary Operating Procedures
These procedures are intended to be used for the initial operation of the expansion system and serve as a basis for a more complete and revised form to be written once operating experience has been gained. An attempt has been made to offer a logical and systematic presentation to facilitate operation and maintenance of the system by the operating personnel. Thus, the sequence of valve actuations has been presented in matrix and check list form to minimize errors; this also has the advantage of making it easier to adapt certain expansion system procedures to programmed control by a process control computer.
80" Bubble Chamber Expansion System Summary of Piston Motion Studies
Prior to assembly into the 80" bubble chamber, the expansion system was subjected to a series of tests to check piston dynamics and gain information on the reliability of the various components. Furthermore, the rest provided operating personnel with the opportunity to become familiar with the operation and maintenance of the expansion system. Two separate tests were performed with the apparatus that was located at the north end of the AGS experimental area; one during the week of Oct. 15 and the other during the week of Nov. 12. The system was run with helium gas supplied from AGS compressor room and the piston was operated at room temperature.
80" Chamber - Low Energy Beams
One of the major, as well as first, decisions which must be taken on a large chamber is to decide on the direction of the magnetic field, i.e., vertical or horizontal. Either alternative has advantages and disadvantages ad it is the intention of this note to discuss these features.
Abscopal Effects of Localized Irradiation by Accelerator Beams
The aim of this series of experiments was to evaluate the existence of abscopal effects of irradiation. No attempt was made towards the elucidation of mechanisms. Very early in the history of radiological research it was noticed radiation produces both local and general effects involving the entire body. Gauss and Lembcke introduced the term "Roentgenkater" (radiation sickness). They ascribed these "General Effects" to the circulation of toxic substances released from cells that disintegrated following irradiation.
The Absolute Yield of the Ferrous Sulfate Oxidation Reaction
The absolute yield of the ferrous sulfate oxidation reaction, under the influence of ionizing radiation, has been determined. A polystyrene, parallel plate ionization chamber, filled with argon, nitrogen, or air, was used to measure the energy absorbed per unit volume of the solution through the application of the Bragg-Gray principle. The ionization current was extrapolated to zero chamber spacing. In related experiments the average ionization potential of polystyrene was determined to be 34.3 ev by comparison with argon and nitrogen. The G value obtained in this experiment using the three gases was 15.9 ± 0.5 ions/100 ev, in good agreement with calorimetric and cathode-ray bombardment measurements.
Absorption and Turnover Rates of Iron Measured by the Whole Body Counter
Human iron metabolism has been extensively studied in the past twenty-five years with the radioisotopes iron⁵⁵ and iron⁵⁹. Before the availability of the whole body counter, however, iron absorption studies were performed by the indirect methods of fecal assay of unabsorbed radioiron, and estimation of red cell incorporation of absorbed tracer. The few long-term excretion studies performed required numerous assumptions, since human iron excretion was less well understood. Whole body counting provides a simple and accurate method of measuring the total body retention of administrative tracer iron⁵⁹, thus making absorption and subsequent excretion determinations possible with a single radioiron study. The energetic gamma emissions of iron⁵⁹ permit ready external detection with small quantities of isotope, Normal radioiron distribution is uniform throughout the circulating red cell mass and thus minimize geometry influences on the counting efficiency, 0nly the 45.1 day half-life of iron⁵⁹ limits long term iron turnover studies. Measurements of iron⁵⁹ absorption and long-term body turnover have been under way at Brookhaven National Laboratory for over two years. The present paper outlines some of the results of these studies, and discusses some implications of the method.
Abstract for the Glasgow Meeting - "International Conference on Nuclear Physics": Gamma Transitions and the Shell Model
The study of the interaction of the electromagnetic field with nuclei has proved very fruitful for the elucidation of many details of nuclear structure. The γ-ray transitions observed in either absorption or emission can be divided into three classes, depending on whether the matrix elements of the transition are (1) much larger, (2) approximately equal or (3) much smaller than those expected for single proton transitions which are usually taken as a norm. In class (1) we find (a) the broad transitions leading to the "giant resonances" in the nuclear photo-electric effect, and (b) the "fast" transitions between low lying states, especially for even-even nuclei far removed from magic numbers. The large matrix elements and the regular dependence of their magnitude on the atomic weight speak for cooperative phenomena in which many nucleons or the nuclei as a whole are involved. In class (2) we find the much studied M4 transitions which give strong support for the single particle model; they have rather uniform matrix elements. Some finer points remain to be understood, especially why some odd nuclei do not show the expected ratio for |M|^2 of ~ 2:1. The transitions belonging to class (3) require further selection rules and are more difficult to describe in general terms. Among the better understood "slow" transitions are some electric transitions which have a reduced transition probability either because they correspond to neutron jumps, or because they involve more than one particle in the transitions.
Acceleration Design Studies for Production of High Center-of-Mass Energies
To aid in planning Brookhaven's future program in high-energy physics, we have just completed a summer study on possible experimentation with super-high-energy accelerators and with storage rings. I should like to review a few of our conclusions and to describe an experiment on coasting beams in progress at Brookhaven. First, however, to provide background for this review, I shall present a short history of the past year. During 1962, many proposals were submitted to the United States Government for design or construction of accelerators for energies above 700 Mev. In order to decide which of these proposals should receive support, an advisory panel was set up under the chairmanship of Professor Norman Ramsey of Harvard. Last April this panel submitted its report. During last April the Brookhaven Laboratory received an official authorization to proceed with studies aimed at the recommended storage rings and super-energy accelerator.
Acceleration of Deuterons or Alpha Particles in the AGS
The magnetic field of the AGS ring can contain particles of magnetic rigidity about 34 Bv/c. This includes not only protons of kinetic energy 33 Bev, but also 32 Bev deuterons, 64 Bev alpha particles, and conceivably heavier nuclei such as 188 Bev carbon nuclei. It will be shown in this paper that such nuclei can be injected and accelerated in the AGS if some rather small modifications are made in the injection and acceleration systems. What physics could be done with such beams? Several types of experiments may be suggested. In the first place, since the deuteron is a rather loosely bound combination of a neutron and a proton, it is likely to break up when it hits a target nucleus (stripping reaction). In a considerable fraction of the collisions the neutron will go straight on with essentially unchanged energy (half the deuteron energy). Therefore, with an internal target bombarded by 30 Bev deuterons one should obtain an intense, rather well collimated and monochromatic beam of 15 Bev neutrons in the forward direction.
Acceleration of Polarized Protons to Relativistic Energies
Maintenance of polarization of polarized protons in a linear accelerator is known to be feasible. Circular accelerators present a different problem, and the investigation of the interaction of orbit dynamics and particle polarization in general is undertaken. The equation of motion of the spin vector of a charged particle in a magnetic field as formulated by Bargmann, Michel, and Telegdi is utilized in the study of depolarization for several accelerators. High values of depolarization are obtained, and means for avoiding such depolarization are suggested. (D.C.W.)
Accelerator Development Department Internal Report
In this report we present solutions of the design problem in which a system of quadruple lenses is required to carry a particle beam from given focal lines in the x and y planes to other given focal lines. Particular attention will be given to the case of the anastigmatic lens system which takes a beam from one focal point to another focal point. Since the general problem is almost impossibly complicated a simplification is introduced by breaking the lens system into two parts. The first part of the lens system is required to bring the initial beam to the state where it is parallel to the z axis in both planes. The second part carries the initially parallel beam to the required final condition. Each part will involve two quadrupoles so that the complete system will consist of four quadruples; usually, however, the field gradients in the second and third quadrupoles can be made identical so that those quadrupoles can be combined into one and the system becomes a three quadrupole system. The configuration of the lens element will be as shown in the figures below. These figures indicate also the general character of the beam path in the two planes.
Accident in Continuous-Dissolver Pilot Plant of Fluoride Volatility Project on May 15, 1957
The so-called Fluoride Volatility Processes refer to several proposed non-aqueous methods of processing irradiated fuel elements. In each of these methods, the uranium is fluorinated to UF6 and then decontaminated by distillation. One of those methods, involving the direct fluorination of the uranium by bromine trifluoride (BTF), has been under investigation at BNL since 1950. In 1952, it was demonstrated at BNL that uranium, as UF6, could be satisfactorily decontaminated by distillation in small-scale pilot plant equipment; end in 1953, BNL undertook the job of determining the technical feasibility of a continuous dissolver on a pilot-plant scale. The reason for the project was that the economic superiority of the process seemed to depend upon its amenability to continuous operation.
Accuracy of Relaxation Length Measurements
We consider here the accuracy of relaxation lengths measured during the water-uranium lattice experiments. Since such an analysis for all measurements would take a great deal of time, we have applied it to just one lattice. This one (2:1 water-to-metal ratio) was chosen completely at random.
Acute Intravenous and Intraperitoneal Toxicity Studies on Sodium Pentaborate Decahydrate and Sodium Tetraborate Decahydrate
This technical report describes the toxicity observations on mice of varying borate-glucose molar ratios and relative potencies (p) (4) for the pentaborate and tetraborate drug. This report outlines the methods and results of this experiment and provides a discussion of the results.
Adaptation of a Commercial Counter X-Ray Diffractometer for Investigations to 3000°C
The rapid advances in many technologically important areas have not only served to accentuate the increased demands for high temperature metals and ceramics but have necessitated a more through knowledge of their physical properties when exposed to high temperature service. Toward this latter end, the use of X-ray diffraction has proved an invaluable tool in providing data of regions of thermal stability, expansion coefficients, solid solubility limits, and phase transformations by direct examination at temperature. Since this Laboratory has for some time now been engaged in the study of refractory nuclear materials, it was thought desirable to employ and possibly extend this technique to temperatures ranging up to 3000°C. This communication will describe the equipment developed for this purpose, with experimental results to be described in subsequent publications.
Additional Experiments on Stored Energy in BNL Reactor Graphite
In the memorandum entitled "Stored Energy in BNL Reactor Graphite", dated February 25, 1953, there is described an experiment conducted by Gurinsky's group to determine the energy per gram of irradiated graphite released in a 200°C anneal. Similar experiments were subsequently conducted by W. Kosiba, differing from the original in two particulars: a) Instead of two graphite samples, one normal, and one irradiated, Kosiba used only an irradiated sample which he heated first to release the stored energy, and then again after the energy was released. In this way, he obtained time against temperature curves for both normal and irradiated graphite from the same sample. (These curves are graphed for each run in Figs. 1 thru 5.) b) The vycor tubing used in the original experiment was not used by Kosiba. Five runs of this experiment were selected, Runs 4P, 13, 36, and 40 at furnace temperatures of 200°C, and Run 45 at a furnace temperature of 400°C.
Adenosinetriphosphate Cleavage During the G-Actin to F-Actin Transformation and the Binding of Adenosinetriphosphate to F-Actin
Since the discovery of the Straub and Feuer as well as Laki et al. that ATP bound to G-actin is transformed to ADP and inorganic phosphate during polymerization of actin (1, 2), it has become increasingly clear that the chemical changes in the nucleotide are related to the change in the physical state of the protein. Barany, Biro, Molnar and Straub have shown that highly purified actin preparation free of any enzyme which would use ATP, ADP or AMP as a substrate still catalyze the breakdown of ATP (3) thus supporting the original idea that the ATP to ADP transformation is related to the globular to fibrous transformation of the actin protein itself. Mommaerts was the first to show that the ADP formed during polymerization remains bound to F-actin and Ulbrecht et al. while extending Mommaert's finding on exhaustively purified actin preparations have shown that the P1 formed during polymerization is not bound to F-actin. The stoichiometry of the splitting and the tightness of binding of the ADP lead inevitably to questions in regard to the position of bond breaking during the hydrolysis and to the nature of the forces involved in the tight binding of ADP to F-actin. To aid in the clarification of these problems, this study using O18 isotope was initiated.
Adsorption Studies on Clay Minerals. III. A Torsion Pendulum Adsorption Balance
Many of the most important properties of the clay minerals are in reality properties of the complex systems clay-water. Since water enters directly into the equilibria between clays and ionic solutions, determination of the water content of the minerals under specified conditions are an obvious necessity in any complete study of these equilibria. A formulation of the thermodynamics involved indicates what information is necessary and how to take it into account. Furthermore, recent results of others indicate that a knowledge of the water adsorption isotherms can profitably be used to help elucidate the structures of the clay minerals.
AEC Research and Development Report: Yield of Kr-85 and Xe-133 in the Thermal Neutron Fission of U-235 and Yield of Kr-85 in the Thermal Neutron Fission of Pu-239
We have made absolute radiochemical measurements of the yields of Kr-85 and Xe-133 in the thermal neutron fission of U-235, and of Kr-85 in the thermal neutron fission of Pu-239. For Kr-85 in U-235 fission, the mean of eight measurements gives the ratio, X/T, of fission yield to half-life: X/T = 0.0253%/yr; σ = 1.59%; 99-1 error of the mean = 2.41%. For Kr-85 in Pu-239 fission, the mean of three measurements gives X/T = 0.0092%/yr; σ = 4.3%. Here σ is the standard deviation of a single measurement expressed as percent of the mean. If the Kr-85 half-life is 10.8 (±4%) yr, the yields are U-235 fission: X = 0.273% (±5% of X). Pu- 239 fission: X = .0994%. The error estimate in the U-235 yield is an accuracy estimate compounded of estimated accuracies of 3% in the X/T value and 4% in the half life. For Xe-133 in U-235 fission, the mean of five measurements gives the yield: X = 6.62%; σ = 0.095% of X; accuracy = ±3% of X. The accuracy estimates are based on a detailed investigation of the possible sources of error in the fission counting, the chemical procedure, and the beta-counting (gas-phase proportional counter). A separate measurement of the yield ratio Xe-133/Kr-85 in U fission agreed closely with the same ratio computed from the absolute yield measurement above. As by-products of this work, we have found: 1) The independent yield of Xe-133 in U-235 fission is not greater than 0.1% of the 133 chain yield. 2) The independent yield of Xe-135 in U-235 fission is 3.5 (± 1.0) percent of the 135 chain yield. 3) The half-life of I-133 is 20.8 (± 0.2) hours. The Kr-85 and Xe-133 absolute yields in U-235 fission, together with the accurate relative yields of Kr and Xe …
"Ages" of the Sikhote Alin Meteorite
The potassium-argon age of the Sikhote Alin iron meteorite has been determined. The value is 1.7 + 0.2 x 10⁹ years. Previous lead data suggest an age of 4.6 x 10⁹ years . The date of solidification may be the sum of these two ages.
AGS Performance and Plans
The scope of the AGS complex has expanded rapidly during the three years since an accelerated beam was first obtained. Demand for research time far exceeds the amount available although facilities have been much increased. At the same time, experiments are being designed which are more complicated than previous ones and which make more stringent demands on the accelerator and on its auxiliary equipment. There is a continuous trend of experiments to particle beams of greater momentum, as the experimental techniques are refined. This use of increased momentum means that larger areas are required for the apparatus and that more power is necessary for the magnetic optics. All beam-sharing at the AGS is done by multiple use of each accelerated pulse because our experience indicates that pulse-by-pulse beam-sharing is relatively inefficient. (Expansion chambers have seldom been used at the AGS.) The problems of scheduling experiments becomes increasingly complex since combinations must be found satisfying the criteria: maximum number of experiments to run simultaneously; minimum downtime to be taken for rearrangement between successive experimental arrays
An Alcohol Drip Apparatus for the Sliding Microtome
In wet sectioning of celloidin embedded tissue it is necessary to maintain a layer of alcohol on the knife and on the surface of the block. The alcohol acts as a lubricant and also prevents drying of the block. The application of alcohol may be done by hand or mechanically. To apply the alcohol by hand while operating the microtome slows down the cutting operation, unless the operator is ambidextrous. In addition, stopping and starting the knife to apply alcohol results in an extensive wasting of tissue due to half-sections and sections of uneven thickness. Unless the knife can be kept moving smoothly at a constant rate the result will be sections of non-uniform thickness regardless of the setting on the microtome.
Alternating Gradient Magnets
The angle by which a magnet deflects the trajectory of a particle in the x-z plane is proportional to the integral [integral not transcribed] taken over the trajectory wherever B≠0. Alternating gradient focusing is achieved by designing magnets so that I=I(x) varies linearly with x over a suitable x interval. Usually this is done by shaping the poles to give a linear variation of By with x while keeping the length of the magnet constant for different x. Certain advantaged may be gained by varying the effective length of the magnet with x and keeping By constant so that the integral varies properly with x. Figure 1 shows several such poles for which the trajectory length, and hence the integral (1), varies approximately from 2/3 to 4/3 of the mean value.
Analysis of Cell Population Kinetics
The relation between trace kinetic parameters of cell populations and the statistics used in studies on cell populations is discussed. It is pointed out that responses in cell populations are complex and subject to many perturbations. Some of these are discussed. It is concluded that a complete check list of sources of error is required for studies of great accuracy, and a calculus to help in combining heterogeneous data is needed for studies of systems of great complexity.
Analysis of Meteorological Tower Data, April 1950 - March 1952, Brookhaven National Laboratory
Report issued by the Brookhaven National Laboratory discussing data collected from two BNL meteorological towers. As stated in the introduction, "results are presented in graphic form rather than tabular form" (p. 1). This report includes tables, maps, illustrations, and photographs.
Analysis with a New Type Mass Spectrometer
The purpose of this paper is to describe the application of a magnetic time of flight mass spectrometer to analytical problems. This new spectrometer has a number of advantageous features. It has a linear mass scale and heavy masses are easily resolved. The whole mass spectrum can be observed continuously on an oscilloscope and changes in its composition are seen instantaneously. The voltage of the ionizing electron beam can be varied continuously while viewing the spectrum, giving additional information about characteristic break-up patterns of complex molecules.
Analytic Spin Functions of a Single Variable
There has been considerable recent interest in the development of spin representations which are operations upon analytical functions. The familiar Pauli spin matrix representation, has been sufficient for the solutions of most problems involving nonrelativistic electron spin, but it is to be hoped that, for some problems, an "analytic" representation could be found which has greater physical significance. The new representations that have been presented all hae spin functions of two or more variables.
The Angular Dependence of Thermal Neutron Spectra in Lattices
This technical report discusses techniques that have been developed for "computing the angular thermal flux spectrum emerging from a lattice. These methods are applied to water lattices and it is found that the computed spectra are sensitive to the geometrical description of the lattice, but insensitive to the anisotropic scattering by water. Comparisons with measured spectra indicate that corrections for gradients and the finite size of the experimental lattice are important." -- from abstract (p. 3).
Annealing of Radiation Induced Defects in Fused Silica
Technical report describes how glasses and crystals subjected to ionizing radiation develop absorption bands and become colored. The coloring of defects can be used to determine how nuclear reactor induced defects anneal out or disappear as an irradiated sample is heated.
Antibody Formation by Transplanted Bone Marrow, Spleen, Lymph Node and Thymus Cells in Irradiated Recipients
The role of the marrow as a site for antibody formation has been considered for many years. In 1912 Ludke reported the appearance of antibody in cultures of marrow cells obtained from previously immunized rabbits. Specific agglutinins for killed typhoid bacilli and lysins for ox red cells and sheep red cells were detected in the culture media 2 to 5 days later. However, the cultured cells failed to produce antibody when these antigens were added to the media. Similar findings by Reiter, Przygode, and Schilf appeared in the early literature with regard to the appearance of antibodies to various antigens in tissue cultures of bone marrow from immunized animals, along with failure to elicit antibody formation by addition of antigen to the culture resulted from the addition of excess amounts of antigen, so that if antibody synthesis occurred, the excess antigen combined with antibody and significant amounts of free antibody could not be detected in the culture media. Thorbecke and Keuning observed an increase in antibody in culture fluids when bone marrow fragments from rabbits immunized to paratyphoid B vaccine were cultured in roller tubes.
Antiproton-Proton Two-Prong Interactions at 3.25 Bev/c
A study is being made of two-prong antiproton interactions in hydrogen at 3.25 Bev/c. About 2250 two-prong events were measured on automatic digitized machines and their reconstruction and analysis were performed with standard programs. Of the total number of events 1003 were classified as elastic interactions. About 500 inelastic events were examined using bubble density estimates in addition to criteria based on distribution values in the classification procedure. The inelastic events in which a secondary nucleon or antinucleon was unambiguously identified were used to obtain limits for annihilation and non-annihilation partial cross sections. The two-prong events were 57% of the total. Results for angular distributions and cross sections are presented in graphs and tables. (M.C.G.)
The Application of Inert Fluidized Beds to the Volatility Reprocessing of Reactor Fuels
In the reprocessing of spent solid fuels from nuclear reactors by direct volatilization, one of the major problems is the removal of heat from the highly exothermic gas-solid reactions. The use of fluidized beds of inert granular material as heat transfer media to control these exothermic reactions forms the basis of one approach to volatile reprocessing which is under development at BNL The engineering scale work carried out under this development program is discussed.
The Approximation with Anisotropic Effects for Cylindrical Geometry
The method of spherical harmonic tensors developed Mark for solving the Boltzmann transport equation in isotropic media is herein extended to anisotropic media for cylindrical geometry. A formal solution is given for the case of two concentric cylindrical media, A and B, but no numerical work has yet been done. The following treatment differs from a similar one by the H. K. Ferguson Co. in that the external medium B is assumed to be both a neutron absorber and finite in extent rather than a non-absorber and infinite in extent.
Area Survey Manual
Report issued by the Brookhaven National Laboratory discussing the area survey manual covering the 15 service stations. Design and operations of the service stations are presented. This report includes tables, illustrations, photographs, and a map.
The Area Survey Manual of Brookhaven National Laboratory: Area Radiation Detection Instrumentation, Maintenance, and Results
Report issued by the Brookhaven National Laboratory discussing the instrumentation, operation, and maintenance of the established area radiation monitoring stations. This report includes maps, tables, illustrations, and photographs.
Automatic Bubble Density Measurement with the Hough-Powell System
The Brookhaven Bubble Chamber Group is developing a Hough-Powell fast analysis system (HPD)1 for bubble chamber photographs. High precision measurements are made with a computer controlled flying spot digitizer. We are currently testing the track selection programs for the system. We have just completed a study of a method for automatic bubble density measurements.
Autoradiographic Study on the Origin and Fate of Small Lymphoid Cells in the Dog Bone Marrow: Effect of Femoral Artery Clamping During in Vivo Availability of Thymidine-H
Mammalian bone marrow contains a considerable number of small lymphoid cells (small lymphocytes and small lymphocyte-like cells). The total number of these cells (50,000 to 500,000 per mm3) depends on species, age and other factors. The origin, function and fate of these cells remain obscure in many respects. In particular, it has not been shown beyond doubt, if and to what extent small lymphoid cells enter the bone marrow via the blood stream or if their origin is in part or entirely within the bone marrow. In addition it has not been clearly shown whether or not these cells may function as multipotential hemopoietic stem cells. Results obtained from experiments with irradiated parabiotic animals and animals given regional fractioned doses of X-irradiation, and transplantation of leukocytes from peripheral blood into lethally irradiated recipients afford indirect evidence that peripheral blood of mice and rats may contain stem cells capable of DNA synthesis and division.
Bacterial Virus: Radiation and Function
One of the materials most extensively studied with the dry state ionizing particle approach described in the preceding papers has been T-1 bacteriophage. It was one of the earliest materials subjected to cyclotron bombardment in the Yale biophysics group (Pollard and Forro, 1951) and a number of workers associated with the group have from time to time returned to it (Pollard and Jane Setlow, 1954). One reason is that investigation of various functional properties of a single material is relatively easy for bacteriophage, and among the T-series coliphages T-1 is the most easily handled dry. Another reason is that the bacteriophage work, as represented to a large extent by T-1, does not fit the one primary ionization - one inactivation conclusion stated in the preceding paper by Dr. R. B. Setlow for many other materials. T-1 is one of the exceptions and we have kept coming back to it to see more clearly why is is exceptional.
The Ball Tuner Change Tables
Technique used in deriving values of the linac ball tuner settings to produce various fields is discussed briefly, and tables showing ball tuner change numbers and values used in making up the ball tuner change numbers are given.
Beam Current Integrator
The object of this report is to acquaint the operator with the operational and technical aspects of the beam current integrator as well as the theory of the system operation. The design and operation of a beam current integrator are described, and the theory of operation is discussed. The instrument has two channels. The console channel is designed to measure the accumulation of charge received by a target during a period of a day no matter what the range used in the experimenter's channel. An analysis indicated that this unit will measure the accumulation of charge by a target to an accuracy of 0.1215% assuming that the constant error due to shorting the integrating capacitor is accounted for. The instrument is ranged to handle from 0.5 to 500 mu a of beam current. (M.C.G.)
Beam Separators for Bev Particles
The problem of separation of beams of particles of different masses but of the same momentum at Bev energies is the subject of a great deal of study at several high energy laboratories. In this note we shall describe the problem and tabulate a few of the cogent parameters. Frequently the student of high energy interactions is faced with a beam of miscellaneous particles coming from an accelerator. By standard techniques this beam can be rendered approximately parallel and an inch or so in diameter. By passage through a magnetic field the beam can be analyzed in momentum. Now it frequently happens that the particles in which the experimenter is particularly interested make up only a small fraction of the beam and the exigencies of the proposed experiment may well demand that the background of undesired particles be drastically reduced. The problem is difficult because the velocities of the various particles are almost equal to each other and to the velocity of lights; this makes time-of-flight techniques relatively ineffective. The energies of the particles are almost equal so electrostatic separation also is difficult. Since the beam is already analyzed in momentum, further separation by magnetic means is impossible.
The Biological Effects of heavy Cosmic Ray Particles
Technical report investigates creating a microbeam of deuterons to simulate cosmic rays and the results of brain irradiation, irradiation of the eye, and irradiation of hair follicles of mice. The report's conclusion was that "astronauts exposed to heavy primary particles over a period of some weeks would be expected to develop gray hairs, but this is the only significant biological damage they would suffer."
Biological Effects of Thermal Neutrons and the B10 (n,c) Li7 Reaction
Boron-10 has a high thermal neutron capture cross section (3880 barns). Following neutron capture, the subsequent nuclear disintegration produces an alpha particle and a lithium-7 nucleus with the release of an average of 2.34 MeV for the particle irradiation, and in 93% of the reactions there is also the emission of an 0.48 MeV gamma ray: [equation not transcribed]. The kinetic energy is divided between the lithium-7 nucleus and the alpha particle giving the equal and opposite momentums with a range in tissue of about 8-14μ or approximately 1 cell diameter (1). This fact and the reported favorable partition of boron between tumor and the normal brain suggested a possible therapeutic usefulness which has been investigated clinically. The object of our study is to document the biological effects of the B10 (n,α) Li7 reaction on the brain of dogs injected with boron-10 30 minutes prior to irradiation with thermal neutrons. For this, we felt it desirable to estimate a dose for the boron-10 reaction which if exceeded, produces destruction of normal tissue. This dose could then be a reference dose to be utilized as a maximal limit for the irradiation of normal tissue. We have assured that the largest fluence of thermal neutrons that permits a healing radioepidermitis in pigs injected with 35 mg/kg of boron-10, 30 minutes prior to irradiation would be suitable first approximation.
Boiling Burnout Newsletter No.1
Preliminary data are enclosed in Tables I, II, II, IV, V, and VI. Tables I to V are data for round nickel tubes in a vertical and inclined (45°) position. Table VI contains some preliminary data for nickel rectangular channels (0.060" and 0.050" spacings) in a vertical position.
Boiling Potassium Heat Transfer Project Loop Design and Development
This technical report reviews the general purposes and immediate goals of the Heat Transfer Group at BNL's study of the heat transfer characteristics of alkali metals with phase change in forced convective flow. This report also presents a brief description of the design and development of the test loop. Figures detailing findings accompany the report.
A Bond-Cell Method for Complex Molecules and Metals
This technical report introduces "some approximations into the basic quantum mechanical theory" so that the theory of the covalent bond and the molecular orbital method "can be combined into one which will yield quantitative rather than qualitative binding energies and cohesive energies and also distinct energy levels and band structure." This approach will provide a common method "suitable to both solid state physicists and physical chemists, for calculating the energy levels in metals and complex molecules." This report also contains figures detailing the findings. (Quotations taken from introduction)
Bromine Exchange in Graphite-Bromine Lamellar Compounds
A kinetic study of the exchange of normal and radioactive bromine in graphite-bromine lamellar compounds has been made at temperatures of 30° to 50°C. Natural and synthetic graphite powders were investigated. Two alternative mechanisms for the exchange, volume diffusion and surface exchange, were considered. The data were in better agreement with the diffusion mechanism. Diffusion coefficients of 10 -9 to 10 -8 cm2/sec and an activation energy of 11 to 14 kcal/mole were calculated for the natural graphite powders. The diffusion coefficients increased with increasing bromine content. Reversibly absorbed bromine exchanged more rapidly than irreversibly absorbed bromine.
Brookhaven Chemo-Nuclear In-Pile Research Loop
The purpose of the Chemo-nuclear In-pile Research Loop is to provide a versatile facility for investigating chemo-nuclear reactions under flow conditions. The loop os designed to handle gaseous systems in conjunction with fixed packages of solid fuel.
Back to Top of Screen