Germans in Germany's Ethnic Neighborhoods

In contrast to most research on the effects on residents of living in an ethnic neighborhood, this paper explores how living within an ethnic neighborhood affects members of the dominant ethnic group - in this case Germans - rather than the minorities that define it. The results indicate that Germans living within ethnic neighborhoods are less well off financially than their peers in other parts of the city, and are more likely to be living in large buildings in need of repair. The analysis did not however suggest that Germans living in ethnic neighborhoods have fewer social contacts, or that they are more likely to be unemployed. Indeed, Germans living within ethnic neighborhoods reported levels of satisfaction with their housing and standard of living equal to Germans elsewhere. These results would seem to paint a rosy picture of the lives of German residents of ethnic neighborhoods, were it not for a notable absence of school-aged German children within these spaces.

K-Electron-Capture-to-Positron-Emission Ratio in the Decays of ^(15)O and ^(19)Ne

The K/β^+ ratio in the decays of ^(19)Ne and ^(15)O have been measured as (9.6 ± 0.3) × 10^(-4) and (10.7 ± 0.6) × 10^(-4), respectively. A gas-flow proportional counter, operating in anticoincidence with the surrounding plastic scintillator, was used. Theoretical K/β^+ ratios for ^(19)Ne and ^(15)O were computed, using exchange-overlap corrections calculated by Vatai and, separately, exchange corrections extrapolated from the results of Bahcall for 14 ≤ Z ≤ 37. The experimental results were found to be in better agreement with Vatai's calculations

Measurements of mechanical Q in levitated paramagnetic crystals

Thermal noise from test masses, arising both from internal noise in the test mass material and from losses in the suspension wires and their attachments, is a significant factor limiting sensitivity of interferometric gravity-wave detectors. To investigate ways of reducing these noise sources we are using magnetic levitation in place of suspension wires. A search for high-Q crystals with magnetic properties allowing tests in moderate field strengths has led us to paramagnetic crystals, and we report preliminary results with small levitated samples of Gadolinium Gallium Garnet (GGG) and Terbium Gallium Garnet (TGG). The technique seems the first to allow Q measurements with no mechanical contact, and may facilitate work aimed at reducing thermal noise

Doppler-Induced Dynamics of Fields in Fabry-Perot Cavities with Suspended Mirrors

The Doppler effect in Fabry-Perot cavities with suspended mirrors is analyzed. Intrinsically small, the Doppler shift accumulates in the cavity and becomes comparable to or greater than the line-width of the cavity if its finesse is high or its length is large. As a result, damped oscillations of the cavity field occur when one of the mirrors passes a resonance position. A formula for this transient is derived. It is shown that the frequency of the oscillations is equal to the accumulated Doppler shift and the relaxation time of the oscillations is equal to the storage time of the cavity. Comparison of the predicted and the measured Doppler shift is discussed, and application of the analytical solution for measurement of the mirror velocity is described

Analysis of a four-mirror cavity enhanced Michelson interferometer

We investigate the shot noise limited sensitivity of a four-mirror cavity enhanced Michelson interferometer. The intention of this interferometer topology is the reduction of thermal lensing and the impact of the interferometers contrast although transmissive optics are used with high circulating powers. The analytical expressions describing the light fields and the frequency response are derived. Although the parameter space has 11 dimensions, a detailed analysis of the resonance feature gives boundary conditions allowing systematic parameter studies

Gaining Access to Housing in Germany: The Foreign Minority Experience

Housing is a critical component of household well being and the extent to which minority households have achieved parity with Germans is a measure of the extent to which this population is integrated into the larger German society. Specifically we examine whether the housing conditions for immigrants2 has improved between 1985 and 1998 despite the greater barriers to upward mobility for low skill workers arising from industrial restructuring. We use regression models to determine the degree to which socioeconomic differences between the two populations account for variations in the average quality of their housing. Finally, given the low number of vacancies in the German housing market and the disadvantaged position of minorities within it, we are interested in measuring the magnitude of the improvements persons of foreign origin are able to make through residential mobility. Our descriptive analyses reveal that although housing conditions for minorities have improved in absolute terms across a wide array of indicators, only in a few instances has the housing quality gap between Germans and persons of foreign origin narrowed. Further, we find that the housing conditions of minorities remained poorer even after controlling for variables thought to be strong predictors of housing quality (income, age, family size etc..) Finally, persons of foreign origin are becoming increasingly likely to move into the large, often geographically and socially isolated apartment complexes built in the post World War II era.

Passive and active seismic isolation for gravitational radiation detectors and other instruments

Some new passive and active methods for reducing the effects of seismic disturbances on suspended masses are described, with special reference to gravitational radiation detectors in which differential horizontal motions of two or more suspended test masses are monitored. In these methods it is important to be able to determine horizontal seismic accelerations independent of tilts of the ground. Measurement of changes in inclination of the suspension wire of a test mass, relative to a direction defined by a reference arm of long period of oscillation, makes it possible to carry this out over the frequency range of interest for earth-based gravitational radiation detectors. The signal obtained can then be used to compensate for the effects of seismic disturbances on the test mass if necessary. Alternatively the signal corresponding to horizontal acceleration can be used to move the point from which the test mass is suspended in such a way as to reduce the effect of the seismic disturbance and also damp pendulum motions of the suspended test mass. Experimental work with an active anti-seismic system of this type is described

Measurement of Tritium as Water Vapor

When Geiger or proportional counters are used for the assay of tritiated water, the sample is usually converted into hydrogen or methane which is included in the counter filling. Measurement of the sample itself as water vapor would appear to be a more direct method which avoids possible uncertainties in the chemical conversion, and this technique has been used recently [1,2]. It will be shown, however, that although counters containing water vapor may have satisfactory characteristics, adsorption effects can introduce large errors

Stabilization of a Fabry-Perot interferometer using a suspension-point interferometer

A suspension-point interferometer (SPI) is an auxiliary interferometer for active vibration isolation, implemented at the suspension points of the mirrors of an interferometric gravitational wave detector. We constructed a prototype Fabry-Perot interferometer equipped with an SPI and observed vibration isolation in both the spectrum and transfer function. The noise spectrum of the main interferometer was reduced by 40 dB below 1 Hz. Transfer function measurements showed that the SPI also produced good vibration suppression above 1 Hz. These results indicate that SPI can improve both the sensitivity and the stability of the interferometer.Comment: 14 pages, 8 figures; added discussion; to be published in Physics Letters