Included in this semi-monthly report written in 1943 are progress with neutron beams, neutron absorption in enriched materials, equipment operation and maintenance reports of the cyclotron neutron source facility, and instrumentation maintenance activities of individuals in the cyclotron group. (GHT)

Among the spallation products obtained from the 350-Mev proton bombardment of Th{sup 232} they have identified two gaseous alpha-emitters which apparently do not decay into any presently known alpha-decay chains. The half-lives observed for the decay of the alpha-activities are 23 minutes and 2.1 hours. These half-lives may be principally determined by an unknown amount of orbital electron capture. At least one alpha-emitting daughter (about 4 hours half-life) has been observed to grow from a gaseous parent, but it has not been determined whether it arises from alpha-decay or electron-capture. Since these gaseous atoms emit alpha-particles it is assumed that they are isotopes of element 86 (emanation or radon) rather than a lighter rare gas. if they were heavy isotopes such as Em{sup 221} or Em{sup 223}, both unknown, they would decay into known alpha-decay series, the neptunium and actinium series, respectively, and so would grow known short lived alpha-emitters which would have been detected. It thus appears reasonable that they must be lighter than the known emanation isotopes.

Correlations of alpha-decay energies in terms of mass number and atomic number have been made for all of the alpha-emitting species now numbering over 100. For each element isotopes show increase in alpha-energy with decrease in mass number except in the region of 126 neutrons where there is an explainable reversal. This reversal has the effect of creating a region of relatively low alpha-energy and long half-life at low mass numbers for such elements as astatine, emanation, francium, and possibly higher elements as had been noted already for bismuth and polonium. Methods and examples of using alpha-decay data to define the energy surface in the heavy element region are discussed. The regularities in alpha-decay are used for predictions of nuclear properties including prediction of the beta-stable nuclides among the heavy elements. The half-life vs. energy correlations show that the even-even nuclides conform well with existing alpha-decay theory, but all nuclear types with odd nucleons show prohibited decay. The reason for this prohibition is not found in spin changes in the alpha-emission but in the assembly of the components of the alpha particle, and this theory is discussed further in terms of observations made on nuclides having two or more alpha-groups. …

Some time ago we started work in an attempt to observe alpha-particle decay in isotopes of atomic number less than 83. In the first experiments, thin targets of gold leaf were bombarded with 190-Mev deuterons in the 184-inch cyclotron. Two alpha-decay periods were observed in these targets; one of 0.7 minutes half-life and another of 4.3 minutes half-life. The alpha-particle energies were 5.7 and 5.2 Mev, respectively. Chemical separations proved that the 4.3-minute period is due to a gold isotope and suggested that the 0.7-minute period is due to a mercury isotope. The mass numbers of these new isotopes have not been determined. However, the results of excitation-functions in the production of the gold isotope by bombarding gold and platinum with protons suggest that its mass number lies in the range 185-188. The work on this isotope indicates that the alpha to electron capture branching ratio is of the order of magnitude of 10{sup -4}, and that positron activity accompanies the 4.3-minute alpha-period.

At the spring, 1949, meeting of the National Academy of Sciences(l) a preliminary account was given of some observations of mesons produced by the 335 Mev x-ray beam from the Berkeley synchrotron. The present paper is a progress report of this work; no claim is made for completeness, but sufficient new data are available to make publication at this time worth while, especially since some of the numerical results given in the earlier report require revision. The x-ray beam, produced by the impact of 335 Mev electrons on a 20 mil thick platinum target, has a width at half maximum of 0.0135 radian (about 1 inch at 6 feet from the target). In all but the earliest experiments the beam was further defined by a 1 inch hole in a lead block, then passed through a piece of carbon which served as the meson source. The x-ray intensity at one meter from the target was about 3500 r per hour (measured behind 1/8 inch of lead) under the best running conditions; the average was about half this. The actual exposures at the carbon meson source (6 feet from the target) ranged from 500 to 2000 r in the later runs. …

This is a progress report on the following: (1) 184-inch Cyclotron Program; (2) 60-inch Cyclotron Operation; (3) Synchrotron Program; (4) Linear Accelerator Operation; (5) Experimental Physics; (6) Theoretical Physics; (7) Isotope Separation Program; (8) Chemistry; (9) Medical Physics; and (10) Health Chemistry and Physics.

The radio-active xenon and iodine evolved during the dissolution of the uranium may present a health hazard within certain areas around the base of the stack through which the dissolver off-gases are discharged. Since the concentration of these elements in the uranium metal is directly proportional to the power of the pile* and is related to decay period of the metal in accordance with their half-lifes, the maximum rate of discharge of these elements from the stack at H.E.W. can be estimated form existing Clinton data. The required wind dilution to reduce the discharging activation to tolerance levels can then be calculated. The time with respect to the start of the metal dissolution at which the maximum rates of discharge will be attained can also be roughly estimated form existing Clinton data. 3 figs., 3 tabs.

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This report discusses effluent dilution of a retention basin at the Hanford Works in 1943. (JL)

This report consists of a discussion concerning maximum allowable tolerance dose for personnel working in a contaminated area on an 8 hour per day basis. It is a follow up of a telephone conversation between the Medical Superintendent at Hanford Works and Dr. Robert Lash of Knoxville, Tennessee on April 13, 1943. (CBS)

This document details activities at the Hanford Works during the month of August 1948. (JL)

In the design of the pile, it was considered advisable never to impose so great a heat load on any tube that the available header pressure would be insufficient to sweep the tube free of vapor if boiling should accidentally be initiated in the tube. Figures are given for the maximum temperature rises permissible, as function of header pressure and orifice diameter.

This paper gives a cost breakdown of all the water facilities in the 100-F area for the month of January, 1948. Also given is the cost of chlorine for addition to the process water system along with where it is added and in what amounts. Lastly, the average figure for the hardness for the Columbia River water at Hanford.

This barely legible document describes the canning process, B area activities, and the 200 area activities.

This barely legible document describes the canning process, autoclave tests, slug weight distributions, and general information on progress in the 100 Area to include: Reactor physics, corrosion, instrument development, plant assistance, slug recovery, outgassing, sniffer tests, statistics, and analytical services.

This document is a letter sent on September 6, 1944. The topic of discussion is the chemical composition of the water in the Columbia River. Tests show the amount of metals, dissolved solids, hardness and turbidity of the water before and after laboratory filtration.

There were seven charges of metal inspected during the month for corrosion and blistering studies. There were no unusual cases of blistering noted and the corrosion rates were normal for this time of year. Borescopic examination of the graphite packing around the ``B`` Hole in the F Pile revealed that the graphite is no more severely cracked than in the D Pile when it was inspected about a year ago. Examination of the graphite at the downstream and of Tube 1385-D did not indicate that any damage had been done by the leak in that tube. Forty one tubes have been charged in the F Pile on Production Test 105-90-P, ``Exposure of TX Metal Slugs.`` The routine job of taking vertical bowing measurements was turned over to the Instrument Department after working with them once in each Area. Installation of Van Stone test units was completed and a brief run was started. Van Stone flanges at both ends of 64 process tubes in both the B and F Piles were measured with a micrometer to determine the minimum amount of metal remaining.

No administrative or operations significant events are reported. Construction in the pile areas, separations areas, and the technical center is reported. The Southern Railroad connection, Richland paving and related work, and housing work is described. Personnel and visitor data is presented.

This report details technical activities of the Hanford Engineer Works for the time period of September 1 through September 7, 1944.

This monthly report details 100 Area technical activities of the Physics Group for the month of August 1949.

This report details events of importance as reported by the Hanford Operations Office for the week ending September 28, 1949.

This is a brief review of the status of the Redox Solvent Extraction Process. Two alternative flowsbeets are included. Planned and current operations are indicated.

None

This report is a discussion between Dr, Robert Stone of Knoxville, Tennessee and Dr. W.D. Norwood, the Medical Superintendent at HAPO, concerning the health hazards involved from working at HAPO and the maximum exposure to gamma radiation which a worker could be exposed to without receiving adverse irreparable damage. (CBS)