A5005945384- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Radio Astronomy Observations and Technology
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Particle Accelerators and Free-Electron Lasers
- Dengue and Mosquito Control Research
- Calibration and Measurement Techniques
- Cosmology and Gravitation Theories
- Viral Infections and Vectors
- Mosquito-borne diseases and control
National Space Activities Commission
2024
University of Bonn
2020-2024
Consejo Nacional de Investigaciones Científicas y Técnicas
2024
Clusters of galaxies can be used as powerful probes to study astrophysical processes on large scales, test theories the growth structure, and constrain cosmological models. The driving science goal SRG/eROSITA All-Sky Survey is assemble a sample X-ray clusters with well-defined selection function determine evolution mass and, hence, parameters. We present here catalog 12 247 optically confirmed galaxy groups detected in 0.2–2.3 keV extended sources 13 116 deg 2 region western Galactic half...
We used dedicated SRG/eROSITA X-ray, ASKAP/EMU radio, and DECam optical observations of a 15 sq.deg region around the interacting galaxy cluster system A3391/95 to study warm-hot gas in outskirts filaments, surrounding large-scale structure its formation process. relate expectations from cosmological hydrodynamic simulations Magneticum suite. trace irregular morphology main clusters their centers out well beyond characteristic radii, $r_{200}$. Between two systems, we observe an emission...
Galaxy cluster gas temperatures ( T ) play a crucial role in many cosmological and astrophysical studies. However, it has been shown that measurements can significantly vary between different X-ray telescopes. These biases propagate to several applications which be used, such as measuring hydrostatic masses constraining the angular variation of parameters. Thus, is important accurately cross-calibrate instruments account for systematic biases. In this work, we present cross-calibration...
ABSTRACT We present the serendipitous discovery of (1) a large double radio relic associated with galaxy cluster PSZ2 G277.93 + 12.34 and (2) new odd circle, ORC J1027–4422, both found in same deep MeerKAT 1.3 GHz wide-band continuum image. The angular separation two arc-shaped relics is ∼16 arcmin or ∼2.6 Mpc for redshift z ≈ 0.158. thin southern relic, which shows several ridges/shocks including one possibly moving inwards, has linear extent ∼1.64 Mpc. In contrast, northern about twice as...
Context. As the closest galaxy cluster, Virgo Cluster is an exemplary environment for study of large-scale filamentary structure and physical effects that are present in cluster outskirts but absent from more easily studied inner regions. Aims. Here, we analysis SRG/eROSITA data five all-sky surveys. Methods. eROSITA allows us to resolve entire its on scales between 1 kpc 3 Mpc, covering a total area sky about 25° by 25°. We utilized image manipulation techniques surface brightness profiles...
The Centaurus cluster is one of the brightest and closest clusters. Previous comprehensive studies were done only in its part (r<30'), where centers main substructures (Cen 30 Cen 45) are located, a small fraction outskirts has been studied. Through this work, we aim to characterize intracluster medium (ICM) morphology properties out radius within which density 200 times critical Universe at redshift cluster, R_ We utilized combined five SRG/eROSITA All-Sky Survey data (eRASS:5) perform...
The pre-merging system of galaxy clusters Abell 3391-Abell 3395 located at a mean redshift 0.053 has been observed 1 GHz in an ASKAP/EMU Early Science observation as well X-rays with eROSITA. projected separation the X-ray peaks two is $\sim$50$'$ or $\sim$ 3.1 Mpc. Here we present inventory interesting radio sources this field around cluster merger. While eROSITA observations provide clear indications bridge thermal gas between clusters, neither ASKAP nor MWA show any diffuse emission...
Clusters of galaxies can be used as powerful probes to study astrophysical processes on large scales, test theories the growth structure, and constrain cosmological models. The driving science goal SRG/eROSITA All-Sky Survey (eRASS) is assemble a sample X-ray-selected clusters with well-defined selection function determine evolution mass and, hence, parameters. We present here catalog 12247 optically confirmed galaxy groups detected in 0.2-2.3 keV extended X-ray sources 13,116deg$^2$ region...
We investigated the origin and gas properties of a simulated galaxy cluster pair, to connect simulation predictions SRG/eROSITA X-ray observations Abell 3391/95 field. The system has been extracted from (352 cMpc/h)^3 volume Magneticum Pathfinder cosmological simulations at z=0.07. tracked back in time main progenitors pair clusters surrounding groups study assembly history its evolution. Similarly observed A3391/95 system, is embedded complex network filaments, with structures aligned over...
Context . About 30% – 40% of the baryons in local Universe remain unobserved. Many these "missing" are expected to reside warm-hot intergalactic medium (WHIM) cosmic web filaments that connect clusters galaxies. SRG/eROSITA performance verification (PV) observations covered about 15 square degrees A3391/95 system and have revealed a ~15 Mpc continuous soft emission connecting several galaxy groups clusters. Aims We aim characterize gas properties cluster outskirts ( R 500 < r 200 )...
Galaxy cluster gas temperatures ($T$) play a crucial role in many cosmological and astrophysical studies. However, it has been shown that $T$ measurements can vary between different X-ray telescopes. These biases propagate to several applications for which be used. Thus, is important accurately cross-calibrate instruments account systematic biases. In this work, we present the cross-calibration SRG/eROSITA Chandra/ACIS, XMM-Newton/EPIC, using first time large sample of galaxy $T$. To do so,...
SRG/eROSITA PV observations revealed the A3391/95 cluster system and Northern Clump (MCXC J0621.7-5242 galaxy cluster) are aligning along a cosmic filament in soft X-rays, similarly to what has been seen simulations before. We aim understand dynamical state of as it enters atmosphere ($3\times R_{200}$) A3391. analyzed joint eROSITA, XMM-Newton, Chandra probe morphological, thermal, chemical properties from its center out radius 988 kpc ($R_{200}$). utilized ASKAP/EMU radio data, DECam...
Contact. The extended ROentgen Survey with an Imaging Telescope Array (eROSITA) telescope on board the Spectrum-Roentgen-Gamma (SRG) mission has completed first eROSITA All-Sky (eRASS:1). It detected ∼10 4 galaxy clusters in western Galactic hemisphere. In radio band, Australian Square Kilometre Pathfinder (ASKAP) its pilot 1 phase of project Evolutionary Map Universe (EMU) 220 000 sources a 270 deg 2 field overlapping eRASS:1. These two surveys are used to study radio-mode active galactic...
The X-ray telescope eROSITA onboard the newly launched SRG mission serendipitously observed galaxy cluster A3408 ($z=0.0420$) during PV observation of AGN 1H0707-495. Despite its brightness and large extent, it has not been by any modern observatory. A neighbouring in NW direction, A3407 ($z=0.0428$), appears to be close at least projection ($\sim 1.7$ Mpc). This pair could a pre- or post-merger state. We perform detailed analysis A3408. construct particle background subtracted exposure...
Methods. We utilized the combined five SRG/eROSITA All-Sky Survey data (eRASS:5) to perform X-ray imaging and spectral analyses of Centaurus cluster in various directions large radii. Surface brightness (SB) profiles out $2R_{200}$ were constructed. acquired gas temperature, metallicity, normalization per area $R_{200}$. compared our results with previous studies, outskirts measurements, simulations. Comprehensive sky background analysis was done across FoV, particular, assess variation...
The properties of the warm-hot intergalactic medium (WHIM) in cosmic filaments are among least quantified units modern astrophysics. Spectrum Roentgen Gamma/eROSITA All Sky Survey (SRG/eRASS) provides a unique opportunity to study X-ray emission WHIM. We applied both imaging and spectroscopic stacking techniques data first four eRASS scans inspect emissions from 7817 identified Sloan Digital (SDSS) optical galaxy samples. obtained 9 σ significant detection total signal 0.3–1.2 keV band....
We present the serendipitous discovery of a large double radio relic associated with merging galaxy cluster PSZ2 G277.93+12.34 and new odd circle, ORC J1027-4422, both found in deep MeerKAT 1.3 GHz wide-band data. The angular separation two arc-shaped relics is 16 arcmin or 2.6 Mpc for redshift z = 0.158. thin southern relic, which shows number ridges/shocks including one possibly moving inwards, has linear extent 1.64 Mpc. In contrast, northern about twice as wide, bright, but only largest...
The new Spectrum Roentgen Gamma (SRG) eROSITA X-ray telescope has a superior response to extended soft X-rays, which makes it ideal for studying low surface brightness emission of cosmic filaments. We search between the two nearby galaxy clusters Abell~3667 and Abell~3651, are separated by projected transverse distance ${\sim}13\,\mathrm{Mpc}$, using data from SRG/eROSITA All-Sky Survey. performed detailed image analysis region conducted redshift sources them. carried out thorough spectral...
As the closest galaxy cluster, Virgo Cluster is an exemplary environment for study of large-scale filamentary structure and physical effects that are present in cluster outskirts but absent from more easily studied inner regions. Here, we exploration SRG/eROSITA data five all-sky surveys. eROSITA allows us to resolve entire its on scales between 1 kpc 3 Mpc, covering a total area sky about 25 by degrees. We utilize image manipulation techniques surface brightness profiles search extended...
The properties of the warm-hot intergalactic medium (WHIM) in cosmic filaments are among least quantified modern astrophysics. eROSITA All Sky Survey (eRASS) provides us with a unique opportunity to study X-ray emission WHIM. We applied both imaging and spectroscopic stacking techniques data first four eRASS scans inspect emissions from 7817 identified Sloan Digital optical galaxy samples. obtained 9-sigma significant detection total signal 0.3-1.2 keV band. introduce novel method estimate...
Context. A significant fraction of the missing baryons in local Universe is expected to reside large-scale filaments that may be observable soft X-ray emission. Until now, however, very few candidate emission have been found individual systems, and none beyond three times virial radius clusters at nodes these filaments. The new Spectrum Roentgen Gamma (SRG) eROSITA telescope has a superior response extended X-rays, which makes it ideal for studying low surface brightness cosmic Aims. We...
The eROSITA X-ray telescope on board the Spectrum-Roentgen-Gamma (SRG) observatory performed calibration and performance verification (CalPV) observations between September 2019 December 2019, ahead of planned four-year all-sky surveys. Most them were deep, pointing-mode observations. We present here catalog detected from set extra-galactic CalPV released to public by German consortium, multiband counterparts these sources. developed a source detection method optimized for point-like sources...
The extended ROentgen Survey with an Imaging Telescope Array (eROSITA) telescope onboard the Spectrum-Roentgen-Gamma (SRG) mission has finished first eROSITA All-Sky (eRASS:1), and detected 10$^4$ galaxy clusters in western Galactic hemisphere. In radio band, Australian Square Kilometre Pathfinder (ASKAP) its pilot 1 phase of project 'Evolutionary Map Universe' (EMU) 220.000 sources a 270 deg$^2$ field overlapping eRASS:1. These two surveys are used to study radio-mode Active Nuclei (AGN)...