Multi-wavelength view of SPT-CL J2106-5844: A massive galaxy cluster merger at z~1.13

  • Kim, HyeongHan (Department of Astronomy, Yonsei University) ;
  • Di Mascolo, Luca (Max-Planck-Institu fur Astrophysik (MPA)) ;
  • Mroczkowski, Tony (European Southern Observatory (ESO)) ;
  • Perrott, Yvette (School of Chemical and Physical Sciences) ;
  • Rudnick, Lawrence (Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota) ;
  • Jee, M. James (Department of Astronomy, Yonsei University) ;
  • Churazov, Eugene (Max-Planck-Institu fur Astrophysik (MPA)) ;
  • Collier, Jordan D. (The Inter-University Institute for Data Intensive Astronomy (IDIA), Department of Astronomy, University of Cape Town) ;
  • Diego, Jose M. (Institute de Fisica de Cantabria (CSIC-UC)) ;
  • Hopkins, Andrew M. (Australian Astronomical Optics, Macquarie University) ;
  • Kim, Jinhyub (Department of Astronomy, Yonsei University) ;
  • Koribalski, Barbel S. (School of Science, Western Sydney University) ;
  • Marvil, Joshua D. (National Radio Astronomy Observatory) ;
  • van der Burg, Remco (European Southern Observatory (ESO)) ;
  • West, Jennifer L. (Dunlap Institute for Astronomy and Astrophysics University of Toronto)
  • Published : 2021.04.13

Abstract

SPT-CL J2106-5844 is the most massive galaxy cluster at z>1 discovered to date. It has been known to be an isolated system with a singular, well-defined halo. However, recent studies provide lines of evidence for its merging state. We strengthen the case with the multi-wavelength observations from ALMA, ACA, ASKAP, ATCA, and Chandra. With the sensitive, high resolution ALMA+ACA observations, we reconstruct the ICM pressure map from the thermal SZ effect. It reveals two main gas components that are associated with the mass clumps inferred from the weak-lensing analysis. Furthermore, the X-ray hardness map supports the bimodal gas distribution. With these multi-wavelength data, we probe the merger phase in SPT-CL J2106-5844.

Keywords