W. Saurer

Spin vector orientations of galaxies in seven Abell clusters of BM type III

We present an analysis of the spatial orientations of 851 galaxies in 7 Abell clusters of BM type III (type III in the Bautz-Morgan system). Anisotropy is found in all 7 clusters. It is found that the spin vector orientations of the galaxies in the clusters of BM type III tend to be oriented both parallel (Abell 1412, Abell 2048 and Abell 4038) and perpendicular (Abell 2061, Abell 2065, Abell 2151 and Abell 2197) to the local supercluster plane. The spin vector projections of galaxies in 5 clusters (Abell 2061, Abell 2065, Abell 2151, Abell 2197 and Abell 4038) is found to be oriented perpendicular to the Virgo cluster center.

Detection of Nonrandom Galaxy Orientations in X-Ray Subclusters of the Coma Cluster

This study on the Coma Cluster suggests that there are deviations from a completely random galaxy orientation on small scales. Since we found a significant coincidence of hot-gas features identified in the latest X-ray observations of Coma with these local anisotropies, they may indicate regions of recent mutual interaction of member galaxies within subclusters that are currently falling in on the main cluster.

Spatial orientation of galaxies in the core of the Shapley concentration - the cluster Abell 3558

We present an analysis of the spatial orientations of 323 galaxies in the cluster Abell 3558. Our aim is to examine non-random effects in galaxy orientations in the subsample of the cluster. The “position angle–inclination” method is used to find the threedimensional rotation axes. To check for anisotropy or isotropy we carried out three statistical tests: Fourier, Kolmogorov-Smirnov, and Kuiper-V. We assumed a spatially isotropic distribution to examine non-random effects. The galaxies found in the investigated cluster region show isotropy in both two- and three-dimensional analyses of the galactic coordinate system. In addition, it is found that the overall isotropic appearance cannot be maintained when looking at the subsamples. The low radial-velocity galaxies in A 3558 showed anisotropy in both two- and three-dimensional analyses. A weak anisotropy is noticed in the hard X-ray emission region. Few subsamples shows similar alignments with respect to both the galactic and Supergalactic coordinate systems. We offer possible explanations of these anisotropies.

Coexistence of chiral symmetry restoration and random orientation of galaxies

We studied the chiral symmetry restoration and the spatial orientation of 2288 spiral and spiral barred galaxies that have radial velocities (RV) less than 5000 km s −1 . A random direction of the rotation of galaxies is assumed in order to classify the structural modes. The distribution of spin vector and spin vector projections of leading and trailing arm galaxies in the total sample and subsamples are studied. We use chi-square, auto-correlation and Fourier tests in order to discriminate the preferred alignments from the random alignments. A good correlation between the random alignment and the chiral symmetry is noticed in the Local Supercluster (RV < 3000 km s −1 ) and in galaxies nearby the Local Supercluster (3000 < RV (km s −1 ) ≤ 5000). Spiral galaxies show a similar result. The barred spirals show an opposite trend to that observed for the spirals. Nearby the Local Supercluster, we noticed a preferred spatial alignment and non-chiral property in the leading and trailing arm spiral barred galaxies. Our result predicts that the progressive loss of chirality might have some connection with the rotationally supported (spirals, barred spirals) and randomized (lenticulars, ellipticals) systems. Thus, we suspect that the dynamical processes in the cluster evolution give rise to a dynamical loss of chirality.

Preferred alignments of angular momentum vectors of galaxies in six dynamically unstable Abell clusters

A spatial orientation of angular momentum vectors of galaxies in six dynamically unstable Abell clusters (S1171, S0001, A1035, A1373, A1474 and A4053) is studied. For this, two-dimensional observed parameters (e.g., positions, diameters and position angles) are converted into three-dimensional (3D) rotation axes of the galaxy using the ‘position angle - inclination’ method. The expected isotropic distribution curves for angular momentum vectors are obtained by performing random simulations. The observed and expected distributions are compared using several statistical tests. No preferred alignments of angular momentum vectors of galaxies are noticed in all six dynamically unstable clusters, supporting the hierarchy model of galaxy formation. These clusters have a larger value of velocity dispersion. However, local effects are noticed in the clusters that have substructures in the 1D-3D number density maps.

Das Physikinteresse von zehn- bis sechzehnjährigen Schülerinnen und Schülern in Tirol

Viele empirische Studien aus Deutschland und den nordischen Landern haben ergeben, dass es im Verlauf der Sekundarstufe I bei Schulerinnen und Schulern zu einem signifikanten Einbruch des Interesses an Physik kommt, insbesondere bei Madchen (siehe z.B. Hoffmann et al., 1998; Honer, 1996; Todt, 1993). Durch verschiedene Initiativen wurde in den letzten Jahren versucht, diesem Interessenabfall entgegenzusteuern. Beispiele dafur sind: das SINUSund SINUS-Transfer Programm unter der Leitung von Prof. Dr. Manfred Prenzel (2009), Zehn Thesen zur physikalischen Bildung (Labudde, 2006), IPN Videostudie Physik (Prenzel et al., 2001), Videostudie zum Physikunterricht in der Schweiz (Fischer et al., 2005), Physik im Kontext – Ein Programm zur Forderung der naturwissenschaftlichen Grundbildung durch Physikunterricht, Lernort Labor (Euler, 2005) und unzahlige weitere (eine Liste findet man in Duit, 2006). Auch zur Forderung der Madchen im Physikunterricht wurden verschiedene Beitrage und Modellversuche konkretisiert z.B. Chancengleichheit – Veranderung des Anfangsunterrichts (Hoffmann et al., 1997), Koedukation im Physikunterricht – Eine Interventionsstudie auf der Sekundarstufe II (Herzog et al., 1997) und andere mehr (eine Ubersicht findet man in Wodzinski, 2007).