Early Results on Radioactive Background Characterization for Sanford Laboratory and DUSEL Experiments

Measuring external sources of background for a deep underground laboratory at the Homestake Mine is an important step for the planned low-background experiments. The naturally occurring $\gamma$-ray fluxes at different levels in the Homestake Mine are studied using NaI detectors and Monte Carlo simulations. A simple algorithm is developed to convert the measured $\gamma$-ray rates into $\gamma$-ray fluxes. A good agreement between the measured and simulated $\gamma$-ray fluxes is achieved with the knowledge of the chemical composition and radioactivity levels in the rock. The neutron fluxes and $\gamma$-ray fluxes are predicted by Monte Carlo simulations for different levels including inaccessible levels that are under construction for the planned low background experiments.Comment: 16 pages, 2 figures, and 9 table

NRQCD results on the MILC extra coarse ensemble

We present preliminary results using NRQCD to describe heavy quarks on the MILC 2+1 flavour dynamical extra coarse ensemble. We calculate the spectra of low lying states in bottomonium to complement earlier results on the finer MILC ensembles. We then exploit the coarseness of the lattices to calculate charm propagators using NRQCD. These are used to examine the charmonium spectrum and to calclate the mass of the $B_c$ using NRQCD. Finally we look breifly at the $B_d$ and $B_s$ systems using the imporoved staggered formalism to describe the light valence quarks.Comment: 6 pages, Talk presented at Lattice 2005 (Heavy Quarks), Dublin, 25-30 July 200

A Case of Head Injury

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A New Framework for Analyzing and Managing Macrofinancial Risks of an Economy

The high cost of international economic and financial crises highlights the need for a comprehensive framework to assess the robustness of national economic and financial systems. This paper proposes a new comprehensive approach to measure, analyze, and manage macroeconomic risk based on the theory and practice of modern contingent claims analysis (CCA). We illustrate how to use the CCA approach to model and measure sectoral and national risk exposures, and analyze policies to offset their potentially harmful effects. This new framework provides economic balance sheets for inter-linked sectors and a risk accounting framework for an economy. CCA provides a natural framework for analysis of mismatches between an entity's assets and liabilities, such as currency and maturity mismatches on balance sheets. Policies or actions that reduce these mismatches will help reduce risk and vulnerability. It also provides a new framework for sovereign capital structure analysis. It is useful for assessing vulnerability, policy analysis, risk management, investment analysis, and design of risk control strategies. Both public and private sector participants can benefit from pursuing ways to facilitate more efficient macro risk accounting, improve price and volatility discovery, and expand international risk intermediation activities.

Equilibrium in the hydrogen-methane-steel system

The equilibrium hydrogen-methane compositions were determined for S.A.E. 1050 steel at 800 and 850 degrees centigrade and for 0.80 percent carbon spring steel at 750, 800, 850, and 900 degrees centigrade;All reactions were carried out at pressures slightly above one atmosphere and equilibrium constants were calculated on the basis of the partial pressures of the active gases and the mol fractions of the iron and iron carbide in the solid phase. The results obtained here were compared with the results of other investigators by calculating the methane-hydrogen equilibrium composition for one atmosphere;The heat effect at 850 degrees centigrade was found to be 23,500 calories for the reaction, 3Feg Inaustenite+CH4 &lrarr2;Fe3Cb Inaustenite +2H2. This value of the heat of reaction was obtained from the slope of the straight line drawn for a plot of log K against 1/T. A value of 14,700 calories was calculated for the heat effect for the reaction, 3Fea+CH 4&lrarr2;Fe3Ca +2H2 at 25 degrees centigrade. This calculation was based on the above heat effect at 850 degrees centigrade and heat capacity and transition data for the reactants and products over the temperature interval

The magnetic fields of forming solar-like stars

Magnetic fields play a crucial role at all stages of the formation of low mass stars and planetary systems. In the final stages, in particular, they control the kinematics of in-falling gas from circumstellar discs, and the launching and collimation of spectacular outflows. The magnetic coupling with the disc is thought to influence the rotational evolution of the star, while magnetised stellar winds control the braking of more evolved stars and may influence the migration of planets. Magnetic reconnection events trigger energetic flares which irradiate circumstellar discs with high energy particles that influence the disc chemistry and set the initial conditions for planet formation. However, it is only in the past few years that the current generation of optical spectropolarimeters have allowed the magnetic fields of forming solar-like stars to be probed in unprecedented detail. In order to do justice to the recent extensive observational programs new theoretical models are being developed that incorporate magnetic fields with an observed degree of complexity. In this review we draw together disparate results from the classical electromagnetism, molecular physics/chemistry, and the geophysics literature, and demonstrate how they can be adapted to construct models of the large scale magnetospheres of stars and planets. We conclude by examining how the incorporation of multipolar magnetic fields into new theoretical models will drive future progress in the field through the elucidation of several observational conundrums.Comment: 55 pages, review article accepted for publication in Reports on Progress in Physics. Astro-ph version includes additional appendice

Long Umbilical Cord.

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Thermal design of the space shuttle external tank

The shuttle external tank thermal design presents many challenges in meeting the stringent requirements established by the structures, main propulsion systems, and Orbiter elements. The selected thermal protection design had to meet these requirements, and ease of application, suitability for mass production considering low weight, cost, and high reliability. This development led to a spray-on-foam (SOFI) which covers the entire tank. The need and design for a SOFI material with a dual role of cryogenic insulation and ablator, and the development of the SOFI over SLA concept for high heating areas are discussed. Further issuses of minimum surface ice/frost, no debris, and the development of the TPS spray process considering the required quality and process control are examined