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Title: Frontier fields: Subaru weak-lensing analysis of the merging galaxy cluster A2744

Journal Article · · Astrophysical Journal
 [1];  [2];  [3];  [4];  [5];  [6];  [7];  [8]
  1. Department of Astrophysical Sciences, 4 Ivy Lane, Princeton, NJ 08544 (United States)
  2. Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)
  3. Department of Physical Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)
  4. INAF/Osservatorio Astronomico di Trieste, Via G.B. Tiepolo 11, I-34143 Trieste (Italy)
  5. WinSet, Falls Church, 6107E Arlington Blvd., VA 22044 (United States)
  6. Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom)
  7. Observatório Nacional, Rua Gal. Jóse Cristino, 20921-400 Rio de Janeiro (Brazil)
  8. Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)

We present a weak-lensing analysis of the merging Frontier Fields (FF) cluster Abell 2744 using new Subaru/Suprime-Cam imaging. The wide-field lensing mass distribution reveals this cluster is comprised of four distinct substructures. Simultaneously modeling the two-dimensional reduced shear field using a combination of a Navarro–Frenk–White (NFW) model for the main core and truncated NFW models for the subhalos, we determine their masses and locations. The total mass of the system is constrained as M{sub 200c}=(2.06±0.42)×10{sup 15} M{sub ⊙}. The most massive clump is the southern component with M{sub 200c}=(7.7±3.4)×10{sup 14} M{sub ⊙}, followed by the western substructure (M{sub 200c}=(4.5±2.0)×10{sup 14} M{sub ⊙}) and two smaller substructures to the northeast (M{sub 200c}=(2.8±1.6)×10{sup 14} M{sub ⊙}) and northwest (M{sub 200c}=(1.9±1.2)×10{sup 14} M{sub ⊙}). The presence of the four substructures supports the picture of multiple mergers. Using a composite of hydrodynamical binary simulations we explain this complicated system without the need for a “slingshot” effect to produce the northwest X-ray interloper, as previously proposed. The locations of the substructures appear to be offset from both the gas (87{sub −28}{sup +34} arcsec, 90% CL) and the galaxies (72{sub −53}{sup +34} arcsec, 90% CL) in the case of the northwestern and western subhalos. To confirm or refute these findings, high resolution space-based observations extending beyond the current FF limited coverage to the west and northwestern area are essential.

OSTI ID:
22882296
Journal Information:
Astrophysical Journal, Vol. 817, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Since 2009, the country of publication for this journal is the UK.; ISSN 0004-637X
Country of Publication:
United Kingdom
Language:
English