Simple temperature sensor with direct readout

Sensor is easy to construct, requires only one operational amplifier, and has very fast response. It provides direct readout of temperature on digital voltmeter

Separation of gas mixtures by centrifugation

Magnetohydrodynamic (MHD) centrifuge utilizing electric currents and magnetic fields produces a magnetic force which develops supersonic rotational velocities in gas mixtures. Device is superior to ordinary centrifuges because rotation of gas mixture is produced by MHD force rather than mechanical means

Nondestructive measurement of capillary tube internal diameter

Technique provides nondestructive method of making quick, accurate determination by measuring electrical resistance of capillary tube when it is filled with electrolyte of known conductivity. Apparatus consists of conductivity cell and equipment for measuring resistance and for monitoring and controlling temperature

Nuclear halo structure from quasielastic charge-exchange reactions

Neutron and proton densities in the nuclear periphery are investigated within (p,n) charge-exchange isobar transitions. For this purpose we have developed parameter-free optical potentials with a detailed treatment of the in-medium $t_{\tau}$ part of the effective interaction. Non local coupled-channel Lane equations are solved to obtain the scattering observables. The use of conventional proton and neutron densities significantly underestimates Fermi (forward-angle) cross-sections in agreement with findings by various other groups. However, we have found model-independent densities which provide a remarkable improvement in the description of the quasielastic scattering data.The densities obtained are consistent with recent measurements at CERN in studies of the neutron-to-proton halo factor f(r)=Z$\rho_n/N\rho_p$ with antiprotons. These findings provide an alternative way to investigate the nuclear periphery, and may also help to solve the long-standing puzzle of the underestimated Fermi cross section in (p,n) charge-exchange phenomena.Comment: 5 pages and 2 figs. Presented at the Baryons-04 Conference (Palaiseau, France, Oct 2004). To appear in Nucl. Phys.

An in-medium full-folding model approach to quasielastic (p,n) charge-exchange reactions

A microscopic description of the quasielastic (p,n) charge-exchange reaction (here, charge-exchange scattering between analogue states) is presented and discussed. Emphasis is focused on the spin-isospin structure of the projectile-target coupling. The model is a coupled-channel extension of the full-folding optical model approach (OMP) developed for nucleon elastic scattering, where emphasis is placed on retaining the genuine off-shell behavior of realistic effective interactions in the nuclear medium. The resulting non-local optical potentials are applied to the calculation of (p,n) differential cross sections, with particular emphasis on small-angle Fermi ($\Delta S=0$) cross-sections to isobaric analog states. These parameter-free results provide a reasonable description of the $^{14}$C(p,n)-data at proton energies above $\sim$100 MeV, but deteriorate for heavier targets. These shortcomings are analyzed and possible ways to correct them are discussed.Comment: 20 pages plus 10 figures. Accepted for publication in Phys. Rev.

Measurements of the dielectric properties of sea water at 1.43 GHz

Salinity and temperature of water surfaces of estuaries and bay regions are determined to accuracies of 1 ppt salinity and 0.3 kelvin surface temperature. L-band and S-band radiometers are used in combination as brightness temperature detectors. The determination of the brightness temperature versus salinity, with the water surface temperature as a parameter for 1.4 GHz, is performed with a capillary tube inserted into a resonance cavity. Detailed analysis of the results indicates that the measured values are accurate to better than 0.2 percent in the electric property epsilon' and 0.4 percent in epsilon''. The calculated brightness temperature as a function of temperature and salinity is better than 0.2 kelvin. Thus it is possible to reduce the measured data obtained with the two-frequency radiometer system with 1 ppt accuracy to values in the salinity range 5 to 40 ppt

Spin structure of spin-1/2 baryon and spinless meson production amplitudes in photo and hadronic reactions

The most general spin structures of the spin-1/2 baryon and spinless meson production operator for both photon and nucleon induced reactions are derived from the partial-wave expansions of these reaction amplitudes. The present method provides the coefficients multiplying each spin operator in terms of the partial-wave matrix elements. The result should be useful in studies of these reactions based on partial-wave analyses, especially, when spin observables are considered.Comment: RevTex 34 pages, revised versio

Plasma tests of sprayed coatings for rocket thrust chambers

Several plasma-sprayed coating systems were evaluated for structural stability in hydrogen plasma and in oxygen plasma mixed with hydrogen plasma. The principal test heat flux was 15 Btu per inch squared seconds. The system consisted of a number of thin 0.002 to 0.020 in. layers of metal oxides and/or metals. The principal materials included are molybdenum nichrome, alumina, and zirconia. The study identifies important factors in coating system fabrication and describes the durability of the coating systems in the test environments. Values of effective thermal conductivity for some of the systems are indicated

Establishing an energy scale for pulse-height distributions from gamma-ray spectrometers based on inorganic scintillators

Energy scale for pulse height distributions from gamma ray spectrometers based on inorganic scintillator