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MEETING XII -- BEVATRON RESEARCH CONFERENCE -- BEVATRON OPERATION

Description: On February 2, the first 10 Mev proton beau was injected from the linear accelerator. Injection parameters were varied to study first turn beams with the magnet excited by a d-c generator. A few minutes after the magnetic field had been adjusted to the value calculated from magnetic measurements. the 180{sup o} beam was observed on fluorescent flags and measured with Faraday cups. During the remainder of the week several radio frequency components were installed and operated. Ground current signals in various pieces of equipment were a limitation in detecting.
Date: March 16, 1954
Creator: Cork, Bruce.

MEETING XIII -- BEVATRON RESEARCH CONFERENCE -- TARGET AREA MODIFICATIONS

Description: The following modifications are planned to facilitate greater usefulness of available target space in the west tangent tank: (1) A 3/32-inch x 6-inch x 106-inch aluminum window is to be added to the outer radius tank wall. (2) One 12-inch x 6-inch air lock is to be added on the inside centerline of the reentrant section on the west tangent tank. (3) Two 24-inch x 30-inch openings are to be cut on the beam centerline in the top of the west tangent tank, one at each end. These openings will accommodate photographic plate wells of various kinds and also a large air lock that is being designed. It is suggested that any other modifications to the target area be presented to E. Lofgren as soon as possible so that the modifications can be programmed with respect to operations. The same general policy holds for target location, viz: (a) Small targets - allocations in west tangent tank; and (b) Large targets - allocations in south tangent tank. The design of two general purpose magnets is in the final stages. Copper for the coils will be ordered soon. The characteristics of these magnets are given. Results of magnetic field measurements on the Bevatron are reported, Some of the details and compromises in design of the magnet are discussed. The pole tip confiscation in the 1 x 4-foot aperture nominally n = 0.6 has been cut to a mechanical slope of 0.63. The laminated pole tips have protruding ears which modify the fringing field at low magnet currents to provide the widest possible aperture at injection. These ears are slotted so that they saturate and at intermediate field values become ineffective. This design represents a compromise between maximum useful field width and maximum obtainable field at peak current. The pole tips contain 21 ...
Date: March 23, 1954
Creator: Chupp, Warren

MEETING XIV -- BEVATRON RESEARCH CONFERENCE -- CHEMISTRY EXPERIMENTS

Description: The main purpose of Chemistry Division personnel in using the Bevatron will be to learn as much as possible about nuclear reactions in the Bev energy range using the radiochemical approach. The type and extent of these experiments will depend greatly on the beam intensity. Significant results can be obtained at 10{sup 6} or 10{sup 7} protons per pulse, but it is highly desirable that this figure ultimately be raised to 10{sup 10} or greater.
Date: March 29, 1954
Creator: Hyde, Earl K.

MEETING XV -- BEVATRON RESEARCH CONFERENCE -- BEVATRON STATUS

Description: On April 1, a new energy peak of 6.1 Bev was attained with the Bevatron. Scattered particles monitored with a counter telescope in triple coincidence gave approximately 100 counts per beam pulse. April 2s the machine was down to air to allow work on beam monitoring equipment. Test operations resumed April 5. Though the total number of accelerated particles is still small, due to low energy beam losses, some cloud chamber tracks have been observed. Several plates have been exposed for Goldhaber. Stars with up to 29 prongs have been observed. The following consists of a discussion of the administration, operation and some of the experimental techniques evolved in the use of the Cosmotron.
Date: April 6, 1954
Creator: Lofgren, E.J.

MEETING XVI -- BEVATRON RESEARCH CONFERENCE -- BEVATRON OPERATION

Description: The occurrence of a fault April 7 caused a short in the stator winding of one of the main generators. Repairs will require at least one month and the total time the generator will be down can be determined only after a further inspection of the damage. In a week or two, after a thorough inspection of the generator and the ignitron system, Bevatron operation will be continued on one generator. Since the targets of use in a Bevatron experiment will depend greatly on the nature of the experiment and the techniques to be employed the ideas presented here relate primarily to the area of research which involves the detection with counters of heavy mesons emitted in the backward direction in the laboratory system. These mesons and their decay products have low kinetic energy over the entire range of Bevatron energies above threshold for production. For this reason discrimination by means of momentum resolution, collimating slits, ionization density and range will be possible.
Date: April 13, 1954
Creator: Lofgren, E.J.

MEETING XVII -- BEVATRON RESEARCH CONFERENCE -- BEVATRON OPERATION

Description: Bevatron operation has been stopped temporarily due to a generator fault. While repairs are being instituted the tank will be down to air for repairs and target installation. Operation on one generator is scheduled for May 3. It has been previously proposed that one could investigate the {pi}{sub 0} lifetime by measuring the converted electron yield from {pi}{sub 0} decay photons as a function of the thickness of a thin target in which both the {pi}{sub 0} production and photon conversion occur. If the lifetime were effectively zero the electron yield should depend quadratically upon thickness; whereas if the lifetime is sufficiently great, this quadratic rise will be delayed as the thickness is increased, due to the distance travelled by the {pi}{sub 0} before decay. In fact, the beginning of the yield dependence is cubic rather than quadratic in character. It is estimated that a lifetime of 10{sup -15} seconds should provide a distinctly detectable effect. The investigation may be considered practical at the Bevatron providing: (a) the production cross section for {pi}{sub 0}'s at 6 Bev is about 100 times that at 340 Mev, (b) a Bevatron pulse of 10{sup 8} protons, with a recirculation of 1000 times thru the thin target can be achieved. Thin foils of Au or of U would be used as targets, with thicknesses of the order of 10{sup -4} cm. Some assumptions about the meson momentum spectrum are implicit in these plans. It has been assumed that tho pion kinetic energy spectrum in the nucleon-nucleon C.M. frame peaks at 0.3 Bev. This gives at 0{sup o} in the laboratory T{sub {pi}} = 1.5 Bev, or a time dilation of {gamma} = 12. Techniques have been evolved for utilization of 6 x 6-inch Ilford G-5 plates of 600{micro}-thickness. A typical operating schedule and some ...
Date: April 20, 1954
Creator: Lofgren, E.J.

MEETING XVIII -- BEVATRON RESEARCH CONFERENCE -- BEVATRON OPERATION and NUCLEAR EMULSION EXPERIMENTS

Description: Results of preliminary tests with photographic emulsions using a lip target are discussed. Some methods for the search of heavy mesons are suggested. The preliminary tests with photographic emulsions were designed to investigate exposure conditions inside the Bevatron. These were carried out with stationary targets, since injected targets were not available at that time. The first exposure was designed to study the shielding required for emulsions placed in the direct beam (9 inches from the magnet conterline) during the entire acceleration cycle. Three 200{micro} Ilford G5 emulsions embedded in various thicknesses of brass were exposed for 30 pulses. Nominal maximum energy of beam was 3.5 Bev. During the second and third exposure (nominal maximum beam energies 4.1 and 6 Bev respectively) a lip target was placed in front of the emulsions. This was designed so as to dampen out the radial oscillations in the first section (.36 inches thick, 1/2 inch radial length). The beam should then hit the second section (.9 inches thick, .75 inch radial length) which is designed to reduce the beam orbit by {approx} 1 1/4 inches and then hit the emulsions on the next turn. 1/2 inch brass absorber was placed ahead of the emulsions.
Date: May 11, 1954
Creator: Lofgren, E.J. & Goldhaber, Gerson

Memorandum on Chemical Reactors and Reactor Hazards

Description: Two important problems in the investigation of reactor hazards are the chemical reactivity of various materials employed in reactor construction and the chracteristics of heat transfer under transient conditions, specifically heat transfer when driven by an exponentially increasing heat source (exp t/T). Although these problems are independent of each other, when studied in relation to reactor hazards they may occur in a closely coupled sequence. For example the onset of a dangerous chemical reactor may be due to structural failure of various reactor components under an exponentially rising heat source originating with a runaway nuclear reactor. For this reason, these two problems should eventually be studied together after an exploratory experimental survey has been made in which they are considered separately.
Date: July 5, 1951
Creator: Mills, M.M.; Pearlman, H.; Ruebsamen, W. & Steele, G., Chrisney, J.

Mercury: A Materials Survey

Description: Report issued by the U.S. Bureau of Mines discussing materials surveys conducted on mercury. As stated in the foreword, "the surveys dealing with metals and minerals summarize the demand-supply position in the United States and include information on production, imports, consumption, exports, substitutes, and pertinent history" (p. v). This report includes maps, tables, illustrations, and photographs.
Date: 1959
Creator: Pennington, James W. & Bailey, Edgar H.

Mesaverde Uranium Deposits in the Yale Point-Black Mountain Area, Arizona

Description: Abstract: To date uranium deposits have been confined to a thin sandstone in a zone near the contact of the Middle and Lower Members of the Toreva Formation and as a leach in the Lower Sandstone Member. On a large scale the deposits are apparently restricted to zones of tectonic deformation. Locally mineralization is primarily controlled by small intraformational channels and cross bedding, and is usually associated with carbonaceous material and quartzose sand lenses.
Date: January 1956
Creator: Meador, John P.

The Metabolism of 2-Caroboxy-4-Ketopentitol Diphosphate

Description: 2-Carboxy-4-ketopentitol is converted enzymatically by a cell-free preparation from spinach leaves into a substance undergoing acid-lactone interconversion. This substance has no phosphate or letone group and is probably a dicarboxylic, six-carbon sugar acid or the saccharic or saccharinic acid type. The significance of these findings with regard to the metabolic role of 2-carboxy-4-ketopentitol diphosphate is discussed.
Date: July 15, 1958
Creator: Moses, V. & Calvin, M.

Metabolism of Thioctic Acid in Algae

Description: Thioctic acid labeled with sulfur-35 has been prepared and i t s metabolism b y algae has been studied. It i s converted by the algae into a number of forms, all of which upon hydrolysis yield either the disulfide o r i t s sulfoxide. One of these constituted the major portion of the labeled material in the chloroplasts. Aerobic metabolism for some minutes i s required to produce this form. Preliminary studies of the chemical nature of this form suggest i t to be esterified on the carboxyl group with a moiety of very high lipid solubility.
Date: April 17, 1956
Creator: Grisebach, Hans; Fuller, R.C. & Calvin, M.

THE METABOLSIM AND TOXICITY OF RADIUM-223 IN RATS

Description: This report covers studies of the excretion and retention of 'tracer' and toxic doses of the 11.2-day Ra{sup 223} isotope, its acute toxicity (organ weight changes, gross and microscopic pathology, and Fe{sup 59} utilization by the bone marrow), and long-term histopathological changes and alterations in the hemogram.
Date: February 21, 1958
Creator: Durbin, Patricia; Durbin, Patricia W.; Asling, C. Willet.; Jeung, Nylan; Williams, Marilyn H.; Post, James. et al.

METAL COMBUSTION PROCESSES. Aeornautical Engineering Laboratory Report No. 473

Description: Since the light metallic elements undoubtedly will play a greater and greater role as propellants in advanced chemical and nuclear-chemical propulsion systems, interest in their burning characteristics is increasing. Presented here are some preliminary conclusions on burning characteristics. These conclusions are based on fundamental physical considerations and not on experimental results. An analytical approach to calculate the burning rate of metals is also suggested. This approach differs from the diffusion-droplet approach in that it includes radiation feed-back and loss terms. Such terms can be important at the high temperatures of the diffusion film surrounding a burning metal. (auth)
Date: August 1, 1959
Creator: Glassman, I.

Metal detector study for Hanford

Description: This study was undertaken at the request of the Hanford Works to investigate the possibility of detecting 3/8 inch diameter boron-steel control-balls which become lodged within cracks between the graphite blocks of an atomic pile. The cracks concerned occur radially from 4 3/16 inch diameter holes which pass vertically through the pile. The problem is complicated by the following facts: The graphite blocks are conducting and will therefore give rise to spurious signals primarily due to the cracks between blocks. Numerous aluminum tubes containing water and bars of uranium pass horizontally through the pile at distances closer to the hole than the ball at its extreme position. The vertical holes themselves are warped in an arbitrary manner. Calculations were made to determine theoretically whether or not the ball could be detected. Best operating frequency and coil design were also determined. Tests were made utilizing a specially designed search coil and a test section of graphite pile. Measurements of particle voltage vs. position relative to the coil were made and compared with that resulting from the graphite.
Date: March 25, 1952
Creator: Hansen, W.O.