Theoretical prediction of the impact of Auger recombination on charge collection from an ion track

A recombination mechanism that significantly reduces charge collection from very dense ion tracks in silicon devices was postulated by Zoutendyk et al. The theoretical analysis presented here concludes that Auger recombination is such a mechanism and is of marginal importance for higher density tracks produced by 270-MeV krypton, but of major importance for higher density tracks. The analysis shows that recombination loss is profoundly affected by track diffusion. As the track diffuses, the density and recombination rate decrease so fast that the linear density (number of electron-hole pairs per unit length) approaches a non-zero limiting value as t yields infinity. Furthermore, the linear density is very nearly equal to this limiting value in a few picoseconds or less. When Auger recombination accompanies charge transport processes that have much longer time scales, it can be simulated by assigning a reduced linear energy transfer to the ion

Cavitation in liquid cryogens

Cavitation in liquid hydrogen and nitrogen flowing in transparent plastic ventur

Incipient and developed cavitation in liquid cryogens

Cavitational flow of liquid nitrogen and liquid hydrogen in Venturi tub

Thermodynamic depressions within cavities and cavitation inception in liquid hydrogen and liquid nitrogen Final report, 15 Jul. 1964 - 15 Dec. 1967

Thermodynamic depressions within cavities and cavitation inception in liquid hydrogen and nitrogen in transparent plastic venturi tube

Comparison of mass limiting two-phase flow in a straight tube and in a nozzle

Mass-limiting and near mass-limiting two-phase flow in straight tube and nozzle of refrigerant flow loop syste

Cavitation inception in liquid nitrogen and liquid hydrogen flowing in a venturi Interim report, 15 Jul. 1964 - 15 Jul. 1967

Cavitation characteristics of liquid hydrogen, and liquid nitrogen flow in plastic ventur

Response of river-dominated delta channel networks to permanent changes in river discharge

Using numerical experiments, we investigate how river-dominated delta channel networks are likely to respond to changes in river discharge predicted to occur over the next century as a result of environmental change. Our results show for a change in discharge up to 60% of the initial value, a decrease results in distributary abandonment in the delta, whereas an increase does not significantly affect the network. However, an increase in discharge beyond a threshold of 60% results in channel creation and an increase in the density of the distributary network. This behavior is predicted by an analysis of an individual bifurcation subject to asymmetric water surface slopes in the bifurcate arms. Given that discharge in most river basins will change by less than 50% in the next century, our results suggest that deltas in areas of increased drought will be more likely to experience significant rearrangement of the delta channel network. Copyright 2010 by the American Geophysical Union

X-ray Studies of Two Neutron Stars in 47 Tucanae: Toward Constraints on the Equation of State

We report spectral and variability analysis of two quiescent low mass X-ray binaries (X5 and X7, previously detected with the ROSAT HRI) in a Chandra ACIS-I observation of the globular cluster 47 Tuc. X5 demonstrates sharp eclipses with an 8.666+-0.01 hr period, as well as dips showing an increased N_H column. The thermal spectra of X5 and X7 are well-modeled by unmagnetized hydrogen atmospheres of hot neutron stars. No hard power law component is required. A possible edge or absorption feature is identified near 0.64 keV, perhaps an OV edge from a hot wind. Spectral fits imply that X7 is significantly more massive than the canonical 1.4 \Msun neutron star mass, with M>1.8 \Msun for a radius range of 9-14 km, while X5's spectrum is consistent with a neutron star of mass 1.4 \Msun for the same radius range. Alternatively, if much of the X-ray luminosity is due to continuing accretion onto the neutron star surface, the feature may be the 0.87 keV rest-frame absorption complex (O VIII & other metal lines) intrinsic to the neutron star atmosphere, and a mass of 1.4 \Msun for X7 may be allowed.Comment: 16 pages, 7 figures, accepted by Ap

Lowering The Threshold: How Far Has The Americans With Disabilities Act Expanded Access To The Courts in Employment Litigation?

The purpose of the Americans with Disabilities Act Amendments Act (“ADAAA”) was to restructure and clarify the definition of the legal term “disability” in the Americans with Disabilities Act of 1990 (“ADA”). One of the three prongs of the ADA’s definition of disability is “a physical or mental impairment that substantially limits one or more major life activities of such individual.” The ADAAA was the result of a compromise reached after thirteen weeks of negotiations between representatives of the business and disabilities communities over its provisions. Like many other compromises, the ADAAA did not leave either side fully satisfied. Almost from its inception, the ADAAA has been a target for legal scholars on both sides of the partisan divide. Some commenters have argued that the law did not go far enough in protecting access to the courts for people with disabilities, and others have argued that the law went too far and would unleash a flood of frivolous litigation. Although the ADAAA has so far met any reasonable expectation for success from a policy standpoint, there are still issues regarding its implementation. This Article reviews selected employment litigation cases since the implementation of the ADAAA and determines whether courts have been able to apply the changes to the major life activity standard in an effective and reasonable manner. It also discusses the historical background of the ADAAA and the ongoing attempts to find or create new major life activities, the new bodily functions amendments to the major life activity standard, and the Equal Employment Opportunity Commission (“EEOC”) guidance that classifies some impairments as being “predictable assessments” for disabilities. This Article also provides an empirical study of ADA cases and the competing scholarly perspectives as to whether the ADAAA has gone too far, or not far enough, in terms of who should or should not be covered, and examines whether experience has proven or disproven the various claims made by scholars, and the unintended consequences of the law’s implementation