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From international conference on bone mineral measurement; Chicago, Illinois, USA (12 Oct 1973). Abstracts of papers presented at the international conference on bone mineral measurement are presented. The papers were grouped into two sessions: a physical session including papers on measuring techniques, errors, interpretation and correlations, dual photon techniques, and data handling and exchange; a biomedical session including papers on bone disease, osteoporosis, normative data, non-disease influences, renal, and activity and inactivity. (ERB)

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We have measured the critical magnetic field for superconductivity In tungsten from 5.5 to 15 mK using a {gamma}-ray anisotropy thermometer, and we have measured the heat capacity between 0.35 and 25 K. Analysis of the data gives H{sub 0} = 1.237 Oe for the 0 K critical field, T{sub c} = 16.0 mK for the critical temperature, {gamma} = 1.008 mJ/mole K{sup 2} for the coefficient of the electronic heat capacity, and {Theta}{sub 0} = 383 K for the 0 K Debye temperature. The measured values of the critical field H{sub c} are consistently higher than those reported by Black, Johnson and Wheatley (BJW) on the CMN temperature scale, but the temperature dependence is similar. This discrepancy and the temperature dependence of H{sub c} suggest that both sets of H{sub c} data are affected by magnetic impurities. Use of the calorimetric {gamma} value permits an improved test of the CMN temperature scale with the very low temperature H{sub c} data obtained by BJW.

The authors present measurements of the invariant cross section for the inclusive reaction p + p {yields} p + X in the region 0.14 < |t| < 0.38 GeV{sup 2}, 100 < s < 750 GeV{sup 2} and 0.07 < M{sub x/s}{sup 2} < 0.20.

Neutral decays and {gamma} conversions have been analyzed in an exposure of the NAL 30 hydrogen bubble chamber to 205 GeV/c pions. This paper presents preliminary results on inclusive cross sections for the production of {Upsilon}'s, K{sub s}{sup 0}'s, {Lambda}{sup 0}'s and {bar {Lambda}}{sup 0}'s by 205 GeV/c {pi}{sup -}p interactions. The experiment was done in the NAL 30 hydrogen bubble chamber. Six hundred and sixty-four neutral decays (or conversions) found in a scan of 3058 {pi}{sup -}p interactions were measured. During measurement, three percent of these events were rejected as not pointing to the primary vertex. Another 29% were discarded by a fiducial volume cut on the neutral vertex.

The authors have measured the doubly differential cross section sd{sup 2}{sigma}/dtdM{sup 2} for the reaction p + p {yields} p + X using 200 GeV incident protons in the external beam at the National Accelerator Laboratory. Here t is the square of the four momentum transfer to the target proton, M{sup 2} is the mass squared of X, and s is the total center of mass energy squared. They cover the region of 0.019 < |t| < 0.19 GeV{sup 2} and 1 < M{sup 2} < 60 GeV{sup 2}. Interesting structure is observed at low |t| and M{sup 2} values.

A new analytical mechanism for distributing air sampling locations around nuclear facilities, including reactors, fuel fabrication, fuel reprocessing and research centers, has been devised. This method was developed to facilitate the efficient incorporation of past experiences into environmental surveillance programs for now or developing installations. The technique provides an initial distribution of air samplers around a site which correlates well with placements on sites which have been occupied by long established programs with their inherent evolution and refinements. The applicability of this approach has been examined by comparing sampling locations in well-established air monitoring programs scattered worldwide with location distributions recommended by this mechanism. Results of these comparisons will be detailed.

Article regarding a reunion for former teachers and students of the Palo Pinto School, including location and a list of event officers. A brief history of the school is included.

The authors describe a state-of-the-art automatic control system as it is used to control a manufacturing process in an explosive environment. Compact, explosion proof sensing devices and a custom designed interface to a controller input are discussed.

A device for automatic dispensing of precise amounts of finely divided solids has been developed. Precision is a function of dispensing time. Smaller than gram quantities may be dispensed at a rate of about 1/3 g/min with a precision corresponding to a weight range of about 0.001 g for a series. The process consists in moving the material with the effect of the vibratory motion of a miniature air-powered vibrator. Operation is automatically controlled by the electronic system of the weighing unit interfaced to the pneumatic dispensing device via a combination fluidic and pneumatic control system.

Preliminary data are presented on {pi}-production in inclusive pp interactions at 200 GeV/c using the NAL 30-inch bubble chamber and downstream wide-gap spark chambers. Correlations between {pi}{sup -}'s are studied. No strong short-range correlation effect is seen in contrast to ISR results. Further details of the physical characteristics of the hybrid system and track reconstruction are described in accompanying papers. In this paper they present preliminary results on correlations between {pi}{sup -}'s in 200 GeV/c pp interactions obtained from the NAL 30-inch bubble chamber-wide gap spark chamber hybrid system. The physical characteristics of the hybrid system and track reconstruction are described in accompanying papers. The data came from a film sample of 5,000 pictures. By selecting frames with no upstream bubble chamber wall interactions and with the number of beam tracks less than 15, they have obtained 596 events (1604 negative tracks) from all topologies in the first measurement pass. By detecting high momentum secondaries in the spark chambers, they have obtained a complete momentum spectra in the entire range of kinematic variables.

The authors describe the track reconstruction and bubble chamber/spark chamber hookup software used in the NAL hybrid spectrometer. Results for 15-200 GeV/c tracks are presented. Further details of the physical characteristics of the hybrid system and preliminary physics results are presented in accompanying papers.

From nuclear science symposium; San Francisco, California, USA (14 Nov 1973). Work has been continued on the development of techniques for imaging spatial elemental distributions by means of differential absorption about the K- absorption edge of the particular element Z. A method to correct for spurious effects due to differential absorption in overlying absorber is described. Initial clinical studies of thyroid iodine images on patierts are presented. Application of absorption edge transmission scanning to measurements of Ca cortent in thin in-vitro samples of rat bone is also discussed. An x-ray source with a broad energy spectrum was used. (CH)

There are numerous reasons for performing environmental measurements for routine health or safety monitoring and to determine the movement of trace elements or radionuclides through our environment to man. This is often a requirement for the licensing of nuclear power reactors, as well as many other meteorological or environmental research experiments. In this paper a variety of sensitive low-level counting systems are discussed from an analyst's viewpoint, centering on a variety of Nal(Tl) and Ge(Li) gamma ray spectrometers. The coincident gamma-ray emitters are most sensitively detected through NaI(Tl) multidimensional gamma ray spectrometry, while single gamma ray emitters are very sensitively detected with Ge(Li) detector systems. NaI(Tl) detector systems are superior in general for environmental measurements. (auth)

From seminar on high-energy accelerator science; Tokyo and Tsukuba, Japan (5 Nov 1973). Parameters for the PEP (Proton-- Electron-- Positron) colliding beam facility and the status of the proposed facility are outlined. - The design study has been a joint effort by SLAC and LBL. (WHK)

ABS>From symposium on fuel and elements for fast reactors; Brussels. Belgium (2 Jul 1973). Developmental programs aimed at fabrication of stainless steelclad PuO/sub 2/ fuel pins are described. Information and data are included on welding fast reactor fuel cans, methods of reducing the incidence of weld cracking, effects of weld stresses, and fuel plug design. (JRD)

From third international corference on atomic collisions in solids; Gatlinburg, Tennessee, USA (23 Sep 1973). Focused sequences of replacement collisions have been studied, especially in association with radiation damage cascades. Radiation-damage events are simulated using a computer program based on binary collision approximations. The results are averaged over a complete set of initial directions of the primary knock-on atom for each primary energy to obtain quantities of physical interest for which the effects of replacement sequences may be made explicit. The calculations are compared with recent experimental results. (auth)

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The dosimetry for a person exposed to a large cloud of /sup 85/Kr, supposed to be uniformly distributed in air, is considered. Methods are described that are general, and will also apply to exposure to an infinite cloud of other noble gases. Computer calculations are used for estimates of dose in an anthropomorphic phantom. The decay scheme of /sup 85/Kr which is taken from MIRD Pamphlet No. 6 is included. There is only one photon and its intensity is only 0.41% per disintegration. (auth)

From international symposium on thermal expansion of solids; Lake of the Czarks, Missouri, USA (7 Nov 1973). A quartz differential dilatometer was interfaced with a Digital Equipment Corporation PDP-8 computer to automatically measure the thermal expansion of solids from 300 to 1000 K. A Carson-Dice Electronic-Mechanicai Micrometer, readable to 2.5 x 10/sup -6/ cm, was employed for length-change measurements accurate to 2.5 x 10/sup -5/ cm. Calibrated Pt/Pt/ sub 90/Rh/sub 10/ thermocouples were used to measure temperature changes to plus or minus 0.22 K. The software and hardware necessary to completely automate the measurements are described. Measurements on National Bureau of Standards certified quartz, tungsten, and copper specimens demonstrated an accuracy of plus or minus 1.5% in determination of the coefficient of thermal expansion. (auth)

The implosion-heating power supply uses four 125-kV generators in series. Each generator consists of a fast 125-kV pulse-forming network made up of capacitors attached to a 1m-wide parallel-plate transmission line which is fed through multiple cables from a 2.5- mu F, 0.5- mu H Marx bank charged to 180 kV. To simplify construction it was decided to do without oil or water for high- voltage insulation and grading. The developments described here are: (1) a low- inductance connection between the 125-kV capacitors and the parallel-plate transmission line using an elastomer gasket capable of holding 200 kV; (2) edge flashover prevention by ballooning'' the sheet insulation, by which a 10-cm edge extension of insulation is capable of withstanding a 200-kV pulse for several microseconds; (3) using the edge flashover for over-voltage prevention; (4) grading of voltage along insulators with conducting plastic sheets to prevent flashover at the load switches and cable connections; and (51 capacitively graded insulating supports for the Marx banks. (auth)

From effects of neutron irradiation upon cell function; Neuherberg, F.R. Germany (22 Oct 1973). Procedures are described for irradiating Tradescantia cuttings with neutrons and x rays. Stamen hairs were scored for various mutations. Results are discussed under the following headings: experimental end points and RBE; influence of dose on RBE; effect of dose rate on RBE; influence of neutron energy on RBE; the RBE of 3.9 GeV nitrogen ions; the influence of hypoxia (OER); and the influence of chromosome volume and ploidy level on RBE; pollen abortion data. Graphs are presented to show survival curves for stamen hairs after neutron and x irradiation and neutron and x-ray dose-response curves for pink mutants, blue giant cells. and colorless mutants. (HLW)

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