Abstract. We investigate the efficiency of galactic mass loss, triggered by ram-pressure stripping and galactic winds of cluster galaxies, on the chemical enrichment of the intra-cluster medium (ICM). We combine N-body and hydrodynamic simulations with a semi-numerical galaxy formation model. By including simultaneously different enrichment processes, namely ram-pressure stripping and galactic winds, in galaxy-cluster simulations, we are able to reproduce the observed metal distribution in the ICM. We find that the mass loss by galactic winds in the redshift regime z>2 is ∼10% to 20% of the total galactic wind mass loss, whereas the mass loss by ram-pressure stripping in the same epoch is up to 5% of the total ram-pressure stripping mass loss over the whole simulation time. In the cluster formation epochs z<2 ram-pressure stripping becomes more dominant than galactic winds. We discuss the non-correlation between the evolution of the mean metallicity of galaxy clusters and the galactic mass losses. For comparison with observations we present two dimensional maps of the ICM quantities and radial metallicity profiles. The shape of the observed profiles is well reproduced by the simulations in the case of merging systems. In the case of cool-core clusters the slope of the observed profiles are reproduced by the simulation at radii below ∼300 kpc, whereas at larger radii the observed profiles are shallower. We confirm the inhomogeneous metal distribution in the ICM found in observations. To study the robustness of our results, we investigate two different descriptions for the enrichment process interaction.

Aims. We investigate whether X-ray observations map heavy elements in the Intra-Cluster Medium (ICM) well and whether the X-ray observations yield good estimates for the metal mass, with respect to predictions on transport mechanisms of heavy elements from galaxies into the ICM. We further test the accuracy of simulated metallicity maps. Methods. We extract synthetic X-ray spectra from N-body/hydrodynamic simulations including metal enrichment processes, which we then analyse with the same methods as are applied to observations. By changing the metal distribution in the simulated galaxy clusters, we investigate the dependence of the overall metallicity as a function of the metal distribution. In addition we investigate the difference of X-ray weighted metal maps produced by simulations and metal maps extracted from artificial X-ray spectra, which we calculate with SPEX2.0 and analyse with XSPEC12.0. Results. The overall metallicity depends strongly on the distribution of metals within the galaxy cluster. The more inhomogeneously the metals are distributed within the cluster, the less accurate is the metallicity as a measure for the true metal mass. The true metal mass is generally underestimated by X-ray observations. The difference between the X-ray weighted metal maps and the metal maps from synthetic X-ray spectra is on average less than 7% in the temperature regime above T > 3 × 10 7 K, i.e. X-ray weighted metal maps can be well used for comparison with observed metal maps. Extracting the metal mass in the central parts (r < 500 kpc) of galaxy clusters with X-ray observations results in metal mass underestimates up to a factor of three.

Aims. We study the X-ray morphology and dynamics of the galaxy cluster Abell 514. Also, the relation between the X-ray properties and Faraday Rotation measures of this cluster are investigated in order to study the connection of magnetic fields and the intra-cluster medium. Methods. We use two combined XMM-Newton pointings that are split into three distinct observations. Results. The data allow us to evaluate the overall cluster properties like temperature and metallicity with high accuracy. The cluster has a temperature of 3.8 ± 0.2 keV and a metallicity of 0.22 ± 0.07 in solar units. Additionally, a temperature map and the metallicity distribution are computed, which are used to study the dynamical state of the cluster in detail. Abell 514 represents an interesting merger cluster with many substructures visible in the X-ray image and in the temperature and abundance distributions. These results are used to investigate the connection between the ICM properties and the magnetic field of the cluster by comparing results from radio measurements. The new XMM-Newton data of Abell 514 confirm the relation between the X-ray brightness and the sigma of the Rotation Measure (S X -σ RM relation).

Abstract. Hitherto unstudied objects from Stephenson's list of Hα emission line objects at high galactic latitude were observed spectroscopically to prove their nature. 9 out of 11 objects show Hα in emission. Spectroscopy combined with photometric information indicates most of them being classical Be stars, while one object is a Post-AGB star and one a T-Tauri star. The classification of two objects, which are showing Hα in emission, is unclear.

We present XMM-Newton observations of the galaxy cluster Abell 514. This cluster shows a very complex X-ray morphology. Radio observations show that there are six radio sources located inside the cluster. This makes it possible to determine the magnetic field strength using the Faraday rotation method. This cluster is an example for the hierarchical growth of structure and a very interesting object for studying the correlation between magnetic field strength and X-ray properties. ResultsAbell 514 was observed with the EPIC cameras on-board XMM. The data was analysed using the Science Analysis Software (SAS). All the X-ray point sources in the field of view were cut out to study only the extended cluster emission. Figure 1. The galaxy cluster A514 as seen with XMM-Newton. The first image shows the main part of the cluster. The substructure rich morphology can be seen. The circles are at the position of the radio sources. The second image shows the spectrum that has been extracted from this area.The XMM-Newton images reveal the complex morphology of the cluster. It consists of a main clump with an elliptical shape on top of an elongated structure, including different smaller sub clumps (see figure 1, first image). The location of three radio point sources that lie inside the XMM field of view are indicated in figure 1. The magnetic field strength in the cluster center has a value of 3-7 µG (Govoni et al. 2001). If the elongated structure in the South-East is excluded the surface brightness profile of the main clump can be approximately fitted with a single beta profile with a beta of 1.98. For the whole cluster, an X-ray spectrum could be extracted (see fig 1, second image) and an overall temperature of the cluster (2.9 to 3.5 keV) as well as a cluster metallicity (0.05 to 0.25 solar abundance) was calculated.256