Population Status of the Illinois Chorus Frog (Pseudacris Streckeri Illinoensis) in Madison County, Illinois, With Emphasis on the New Poag Road/FAP 413 Interchange and FAP 413 Wetland Mitigation Site. Report on 1993 Results.

IDOT Contract 1-5-90179INHS Technical Report prepared for Illinois Department of Transportatio

The Cosmic Large-Scale Structure in X-rays (CLASSIX) Cluster Survey I: Probing galaxy cluster magnetic fields with line of sight rotation measures

To search for a signature of an intracluster magnetic field, we compare measurements of Faraday rotation of polarised extragalactic radio sources in the line of sight of galaxy clusters with those outside. We correlated a catalogue of 1383 rotation measures (RM) of extragalactic polarised radio sources with X-ray luminous galaxy clusters from the CLASSIX survey (combining REFLEX II and NORAS II). We compared the RM in the line of sight of clusters within their projected radii of r_500 with those outside and found a significant excess of the dispersion of the RM in the cluster regions. Since the observed RM is the result of Faraday rotation in several presumably uncorrelated magnetised cells of the intracluster medium, the observations correspond to quantities averaged over several magnetic field directions and strengths. Therefore the interesting quantity is the standard deviation of the RM for an ensemble of clusters. We found a standard deviation of the RM inside r_500 of about 120 +- 21 rad m^-2. This compares to about 56 +- 8 rad m^-2 outside. We show that the most X-ray luminous and thus most massive clusters contribute most to the observed excess RM. Modelling the electron density distribution in the intracluster medium with a self-similar model, we found that the dispersion of the RM increases with the column density, and we deduce a magnetic field value of about 2 - 6 (l/10kpc)^-1/2 microG assuming a constant magnetic field strength, where l is the size of the coherently magnetised intracluster medium cells. This magnetic field energy density amounts to a few percent of the average thermal energy density in clusters. When we assumed the magnetic energy density to be a constant fraction of the thermal energy density, we deduced a slightly lower value for this fraction of 3 - 10 (l/10kpc)^-1/2 per mille.Comment: 7 pages, 6 figures, in press, Astronomy and Astrophysics, 201

A multi-frequency study of the peculiar interacting system Arp 206

Arp 206 is a nearby, relatively large, and bright interacting system comprising unequal members: NGC 3432 and UGC 5983. A third anonymous galaxy, Arp 206c, is visible in the field. The CCD images show a well-developed bridge between NGC 3432 and UGC 5983. On the other hand, the complex H I tails are not visible in the optical. In the total H I map, the bridge is lost in a general envelope encompassing both galaxies. The bridge also appears to have some radio emission. On the Total H I map the system is rather edge-on, far more than it would appear in optical wavelengths. UGC 5983 falls exactly in line with NGC 3432. The velocity of the centers of mass of NGC 3432 and UGC 5983 are 530 km s(exp -1) and 630 km s(exp -1), respectively. In view of the considerable damage sustained by NGC 3432 and the apparent low mass of UGC 5983, it appears that the passage must have been at near parabolic speed, with a small pericentric distance and a very low inclination with rspect to the disk of NGC 3432. The apparent distribution of H I along the z axis of the galaxy could be accounted for by projection effects. The tidal appendage found at higher velocities, which rises at a P.A. approx. equal to 25 degrees west of the main body of the galaxy is probably the tail, the part of the tidal damage away from the perturbing companion. The bridge may be rising north-east from the galaxy and then continue under to the south of the galaxy. The relative sizes of the appendages would indicate that the pericenter was crossed recently. Any further inferences about the collision parameters will need to await the results of detailed computational modelling of the interaction. The authors also summarize the observational characteristics of NGC 3432, UGC 5983, and Arp 206c

Superconductivity and Pairing Fluctuations in the Half-Filled Two-Dimensional Hubbard Model

The two-dimensional Hubbard model exhibits superconductivity with d-wave symmetry even at half-filling in the presence of next-nearest neighbor hopping. Using plaquette cluster dynamical mean-field theory with a continuous-time quantum Monte Carlo impurity solver, we reveal the non-Fermi liquid character of the metallic phase in proximity to the superconducting state. Specifically, the low-frequency scattering rate for momenta near (\pi, 0) varies non-monotonously at low temperatures, and the dc conductivity is T-linear at elevated temperatures with an upturn upon cooling. Evidence is provided that pairing fluctuations dominate the normal-conducting state even considerably above the superconducting transition temperature.Comment: 4.3 pages, 4 figure

Hydrodynamical simulations and similarity relations for eruptive mass loss from massive stars

Motivated by the eruptive mass loss inferred from Luminous Blue Variable (LBV) stars, we present 1D hydrodynamical simulations of the response from sudden energy injection into the interior of a very massive ($100 \, M_\odot$) star. For a fiducial case with total energy addition set to a factor $f=0.5$ of the net stellar binding energy, and applied within the stellar envelope, we detail the dynamical response that leads to ejection of the outermost $7.2 \, M_\odot$. We find that the ejecta's variations in time $t$ and radius $r$ for the velocity $v$, density $\rho$, and temperature $T$ are quite well fit by similarity forms in the variable $r/t \approx v$. Specifically the scaled density follows a simple exponential decline $\rho t^{3} \sim \exp (-r/v_{\rm o} t)$. This `exponential similarity' leads to analytic scaling relations for total ejecta mass $\Delta M$ and kinetic energy $\Delta K$ that agree well with the hydrodynamical simulations, with the specific-energy-averaged speed related to the exponential scale speed $v_{\rm o}$ through ${\bar v} \equiv \sqrt{2 \Delta K/\Delta M} = \sqrt{12} \, v_{\rm o}$, and a value comparable to the star's surface escape speed, $v_{\rm esc}$. Models with energy added in the core develop a surface shock breakout that propels an initial, higher-speed ejecta ($>$5000km s$^{-1}$), but the bulk of the ejected material still follows the same exponential similarity scalings with ${\bar v} \approx v_{\rm esc}$. A broader parameter study examines how the ejected mass and energy depends on the energy-addition factor $f$, for three distinct model series that locate the added energy in either the core, envelope, or near-surface. We conclude by discussing the relevance of these results for understanding LBV outbursts and other eruptive phenomena, such as failed supernovae and pulsational pair instability events.Comment: 14 Pages, 12 figures; MNRAS, in pres

MNE’s Regional Location Choice - A Comparative Perspective on East Germany, the Czech Republic and Poland

The focus of this article is the empirical identification of factors influencing Foreign Direct Investment (FDI) in transition economies on a regional level (NUTS 2). The analysis is designed as benchmark between three neighboring post-communist regions, i.e. East Germany, the Czech Republic and Poland. Their different transition paths have not only resulted in economic differences. We can also observe today that the importance of pull factors for FDI varies significantly across the regions. This analysis shows that in comparison with Poland and the Czech Republic, East Germany’s major benefit is its purchasing power, its geographical proximity to West European markets, and its modern infrastructure. Furthermore, the analysis suggests that intra-industry linkages such as specialization and agglomeration economies are relevant factors for the location decision of foreign investors. This result can help to explain the regional divergence of FDI streams in transition economies.multinational enterprises, international business, regional economic activity: growth, development, and changes, discrete choice