Analysis of low resolution mass spectra

Computer program determines gas constituents from measurements of mass/peak-height spectrum from residual gas analyzer. Applications of program include residual gas analysis for work in space environmental simulators, space environment contamination, and air pollution monitoring

Omni-directional anisotropic molecular trap Patent

Omnidirectional anisotropic molecular trap, used with vacuum pump to simulate space environments for testing spacecraft component

Quality Improvement in Health Care: A Framework for Price and Output Measurement

The durability of health care treatment, the substantial technical change in health care treatment, and the prevalence of third-party payment interact to create substantial difficulty in measuring the price and output of health care. This paper provides a framework for analyzing the demand for health care taking into account these difficulties. It then suggests how this framework might be used to improve measurement of health care prices and output.

Photoassociation adiabatic passage of ultracold Rb atoms to form ultracold Rb_2 molecules

We theoretically explore photoassociation by Adiabatic Passage of two colliding cold ^{85}Rb atoms in an atomic trap to form an ultracold Rb_2 molecule. We consider the incoherent thermal nature of the scattering process in a trap and show that coherent manipulations of the atomic ensemble, such as adiabatic passage, are feasible if performed within the coherence time window dictated by the temperature, which is relatively long for cold atoms. We show that a sequence of ~2*10^7 pulses of moderate intensities, each lasting ~750 ns, can photoassociate a large fraction of the atomic ensemble at temperature of 100 microkelvin and density of 10^{11} atoms/cm^3. Use of multiple pulse sequences makes it possible to populate the ground vibrational state. Employing spontaneous decay from a selected excited state, one can accumulate the molecules in a narrow distribution of vibrational states in the ground electronic potential. Alternatively, by removing the created molecules from the beam path between pulse sets, one can create a low-density ensemble of molecules in their ground ro-vibrational state.Comment: RevTex, 23 pages, 9 figure

Analysis and performance of the gas-lubricated tilting pad thrust bearing Interim report

Optimal design and performance criteria for gas lubricated tilting pad thrust bearin

A formalism for the construction of binary neutron stars with arbitrary circulation

Most numerical models of binary stars - in particular neutron stars in compact binaries - assume the companions to be either corotational or irrotational. Either one of these assumptions leads to a significant simplification in the hydrodynamic equations of stationary equilibrium. In this paper we develop a new formalism for the construction of binary stars with circulation intermediate between corotational and irrotational. Generalizing the equations for irrotational flow we cast the Euler equation, which is an algebraic equation in the case of corotational or irrotational fluid flow, as an elliptic equation for a new auxiliary quantity. We also suggest a parameterized decomposition of the fluid flow that allows for a variation of the stellar circulation.Comment: 8 pages, no figures; published version with erratu

Luminosity versus Rotation in a Supermassive Star

We determine the effect of rotation on the luminosity of supermassive stars. We apply the Roche model to calculate analytically the emitted radiation from a uniformly rotating, radiation-dominated supermassive configuration. We find that the luminosity at maximum rotation, when mass at the equator orbits at the Kepler period, is reduced by ~36% below the usual Eddington luminosity from the corresponding nonrotating star. A supermassive star is believed to evolve in a quasistationary manner along such a maximally rotating ``mass-shedding'' sequence before reaching the point of dynamical instability; hence this reduced luminosity determines the evolutionary timescale. Our result therefore implies that the lifetime of a supermassive star prior to dynamical collapse is ~56% longer than the value typically estimated by employing the usual Eddington luminosity.Comment: 5 pages, 2 figures, uses emulateapj.sty; to appear in Ap