The eROSITA view of the Abell 3391/95 field: The Northern Clump: The largest infalling structure in the longest known gas filament observed with eROSITA, XMM-Newton, and Chandra

Angie Veronica, Yuanyuan Su, Veronica Biffi, Thomas H. Reiprich, Florian Pacaud, Paul E.J. Nulsen, Ralph P. Kraft, Jeremy S. Sanders, Akos Bogdan, Melih Kara, Klaus Dolag, Jürgen Kerp, Bärbel S. Koribalski, Thomas Erben, Esra Bulbul, Efrain Gatuzz, Vittorio Ghirardini, Andrew M. Hopkins, Ang Liu, Konstantinos MigkasTessa Vernstrom

Research output: Contribution to journalArticlepeer-review

9 Scopus citations

Abstract

Context. Galaxy clusters grow through mergers and the accretion of substructures along large-scale filaments. Many of the missing baryons in the local Universe may reside in such filaments as the warm-hot intergalactic medium (WHIM). Aims. SRG/eROSITA performance verification observations revealed that the binary cluster Abell 3391/3395 and the Northern Clump (the MCXC J0621.7-5242 galaxy cluster) are aligning along a cosmic filament in soft X-rays, similarly to what has been seen in simulations before. We aim to understand the dynamical state of the Northern Clump as it enters the atmosphere (3 ÃÂ-R200) of Abell 3391. Methods. We analyzed joint eROSITA, XMM-Newton, and Chandra observations to probe the morphological, thermal, and chemical properties of the Northern Clump from its center out to a radius of 988 kpc (R200). We utilized the ASKAP/EMU radio data, the DECam optical image, and the Planck y-map to study the influence of the wide-angle tail (WAT) radio source on the Northern Clump's central intracluster medium. Using eROSITA data, we also analyzed the gas properties of the Northern Filament, the region between the virial radii of the Northern Clump and the A3391 cluster. From the Magneticum simulation, we identified an analog of the A3391/95 system along with an infalling group resembling the Northern Clump. Results. The Northern Clump is a weak cool-core cluster centered on a WAT radio galaxy. The gas temperature over 0.2-0.5R500 is kBT500 = 1.99 ± 0.04 keV. We employed the mass-temperature (M -T) scaling relation and obtained a mass estimate of M500 = (7.68 ± 0.43) ÃÂ-1013 M and R500 = (63 6 ± 12) kpc. Its X-ray atmosphere has a boxy shape and deviates from spherical symmetry. We identify a southern surface brightness edge, likely caused by subsonic motion relative to the filament gas in the southern direction. At ~R500, the southern atmosphere (infalling head) appears to be 42% hotter than its northern atmosphere. We detect a downstream tail pointing toward the north with a projected length of ~318 kpc, plausibly the result of ram pressure stripping. Through a two-temperature fit, we identify a cooler component in the Northern Filament with kBT = 0.68- 0.64+ 0.38 keV kBT=0.68 0.64+0.38keV and ne = 1.99-1.24+0.88 ÃÂ-10-5cm-3, ne1.99 1.24+0.88ÃÂ-*10 5cm 3 which are consistent within the expected ranges of WHIM properties. The analog group in the Magneticum simulation is experiencing changes in its gas properties and a shift between the position of the halo center and that of the bound gas, while approaching the main cluster pair. Conclusions. The Northern Clump is a dynamically active system and far from being relaxed. Its atmosphere is affected by an interaction with the WAT and by gas sloshing or its infall toward Abell 3391 along the filament, consistent with the analog group-size halo in the Magneticum simulation.

Original languageEnglish
Article numberA46
JournalAstronomy and Astrophysics
Volume661
DOIs
StatePublished - May 1 2022

Bibliographical note

Funding Information:
aboard SRG, a joint Russian-German science mission supported by the Russian Space Agency (Roskosmos), in the interests of the Russian Academy of Sciences represented by its Space Research Institute (IKI), and the Deutsches Zentrum für Luft-und Raumfahrt (DLR). The SRG spacecraft was built by Lavochkin Association (NPOL) and its subcontractors, and is operated by NPOL with support from the Max Planck Institute for Extraterrestrial Physics (MPE). The development and construction of the eROSITA X-ray instrument was led by MPE, with contributions from the Dr. Karl Remeis Observatory Bamberg and ECAP (FAU Erlangen-Nuernberg), the University of Hamburg Observatory, the Leibniz Institute for Astrophysics Potsdam (AIP), and the Institute for Astronomy and Astrophysics of the University of Tübingen, with the support of DLR and the Max Planck Society. The Argelander Institute for Astronomy of the University of Bonn and the Ludwig Maximilians Universität Munich also participated in the science preparation for eROSITA. The eROSITA data shown here were processed using the eSASS/NRTA software system developed by the German eROSITA consortium. Partly based on observations obtained with XMMNewton , an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. We acknowledge the Wajarri Yamatji people as the traditional owners of the Murchison Radio-astronomy Observatory, where ASKAP is located.

Funding Information:
cA knowledgements. We would like to thank the anonymous referee for their valuable feedback that helped improve the manuscript. We thank Kaustuv moni Basu for discussion about the Planck y-map. Funded by the Deutsche Forschungs-gemeinschaft (DFG, German Research Foundation) – 450861021. This research was supported by the Excellence Cluster ORIGINS which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC-2094 – 390783311. V.B. acknowledges funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – 415510302. Y.S. acknowledges support from Chandra grants AR8-19020A and GO1-22126X. A.V. is a member of the Max-Planck International School for Astronomy and Astrophysics (IMPRS) and of the Bonn-Cologne Graduate School for Physics and Astronomy (BCGS), and thanks for their support. This work is based on data from eROSITA, the soft X-ray instrument

Funding Information:
We would like to thank the anonymous referee for their valuable feedback that helped improve the manuscript. We thank Kaustuv moni Basu for discussion about the Planck y-map. Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)-450861021. This research was supported by the Excellence Cluster ORIGINS which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy-EXC-2094-390783311. V.B. acknowledges funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)-415510302. Y.S. acknowledges support from Chandra grants AR8-19020A and GO1-22126X. A.V. is a member of the Max-Planck International School for Astronomy and Astrophysics (IMPRS) and of the Bonn-Cologne Graduate School for Physics and Astronomy (BCGS), and thanks for their support. This work is based on data from eROSITA, the soft X-ray instrument aboard SRG, a joint Russian-German science mission supported by the Russian Space Agency (Roskosmos), in the interests of the Russian Academy of Sciences represented by its Space Research Institute (IKI), and the Deutsches Zentrum fur Luft- und Raumfahrt (DLR). The SRG spacecraft was built by Lavochkin Association (NPOL) and its subcontractors, and is operated by NPOL with support from the Max Planck Institute for Extraterrestrial Physics (MPE). The development and construction of the eROSITA X-ray instrument was led by MPE, with contributions from the Dr. Karl Remeis Observatory Bamberg and ECAP (FAU Erlangen-Nuernberg), the University of Hamburg Observatory, the Leibniz Institute for Astrophysics Potsdam (AIP), and the Institute for Astronomy and Astrophysics of the University of Tubingen, with the support of DLR and the Max Planck Society. The Argelander Institute for Astronomy of the University of Bonn and the Ludwig Maximilians Universitat Munich also participated in the science preparation for eROSITA. The eROSITA data shown here were processed using the eSASS/NRTA software system developed by the German eROSITA consortium. Partly based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. We acknowledge the Wajarri Yamatji people as the traditional owners of the Murchison Radio-astronomy Observatory, where ASKAP is located

Publisher Copyright:
© 2022 EDP Sciences. All rights reserved.

Keywords

  • Galaxies: clusters: individual: A3391
  • Galaxies: clusters: individual: MCXCJ0621.7-5242
  • Galaxies: clusters: individual: Northern Clump
  • Galaxies: clusters: intracluster medium
  • X-rays: galaxies: clusters

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'The eROSITA view of the Abell 3391/95 field: The Northern Clump: The largest infalling structure in the longest known gas filament observed with eROSITA, XMM-Newton, and Chandra'. Together they form a unique fingerprint.

Cite this