Participation in large international collaborations and consortia

Athena/WFI Consortium: members of the Science Team that defines the science goals and technical requirements of the Wide Field Imager (WFI) of the Athena X-ray Observatory, currently the L2 mission of ESA. Participation in the ground segment team of the WFI instrument and involved in the development of routines for the detection of X-ray sources on the Athena/WFI images. The image on the right shows a simulated 500ks Athena/WFI observations of the Chandra Deep Field South (Credit: Athena Community Office).

Simulated 500ks Athena/WFI image of the Chandra Deep Field South point source population enhanced by a set of simulated clusters of galaxies. End-to-End simulation generated with SIXTE. Credit Athena Community Office.

The energetic universe as seen with the eROSITA X-ray telescope. The first eROSITA all-sky survey was conducted over a… [more] Credit: Jeremy Sanders, Hermann Brunner and the eSASS team (MPE); Eugene Churazov, Marat Gilfanov (on behalf of IKI)

eROSITA German Consortium: The eROSITA X-ray telescope on-board the Russian-German SRG (Spectrum-Roentgen-Gamma) observatory scans the entire sky to provide the deepest All-Sky Survey at soft X-ray energies (0.2-2.6keV). We are developing routines for the source detection chain of the eROSITA Science Analysis Software System. Our group is also involved in the science exploitation of the eROSITA data by studying the statistical properties of the Active Galactic Nuclei found by eROSITA.

XMM-XXL Survey Collaboration: The XMM-XXL is the largest contiguous X-ray survey carried out by the XMM-Newton X-ray telescope with a total invested time of over 6Ms. It consists of two extragalactic regions of 25deg² down to a point-source sensitivity of ~ 5 10^-15 erg/s/cm² in the 0.5-2keV band. The main goal of the project is to constrain the Dark Energy equation of state using clusters of galaxies. This survey will also have lasting legacy value for cluster scaling laws and studies of AGNs and X-ray background. The group is involved in both the cosmological analysis of the data as well as the AGN science.

The X-ray image of the XMM-XXL southern field with a total sky area of 25deg2, an area about 100 times bigger than the size of the moon. The red circles on the image mark the positions of clusters of galaxies. Also visible against the blue background are white dots. These are Active Galactic Nuclei (Credit: ESA/XMM-Newton/XXL survey consortium)

NEXUS Survey

Matter in the Universe is not evenly distributed but forms a cosmic web of filaments shaped by gravity, with galaxy clusters found at their intersections. Galaxy clusters are the largest bound entities in the Universe – they trace the highest density peaks in its large-scale structure, making them a powerful tool for answering questions about cosmology.

The NEXUS Survey is an X-ray galaxy cluster search in the XMM-Newton Science Archive (XSA). The main goal of the survey is the compilation of a well-selected cluster sample suitable for cosmological analyses. The structure and evolution of the Universe is described by a set of cosmological parameters, which include the density of its various components and the rate that it is expanding. Currently, we know the value of many of these parameters fairly well, but large samples of cosmic tracers at a variety of distances are required to more accurately describe the underlying structure of the Universe.