Asymmetric surface brightness structure of caustic crossing arc in SDSS J1226+2152: a case for dark matter substructure

  title={Asymmetric surface brightness structure of caustic crossing arc in SDSS J1226+2152: a case for dark matter substructure},
  author={Liang Dai and Alexander A. Kaurov and Keren Sharon and Michael K. Florian and Jordi Miralda-Escud'e and Tejaswi Venumadhav and Brenda Frye and Jane R. Rigby and Matthew B. Bayliss},
We study the highly magnified arc SGAS J122651.3+215220 caused by a star-forming galaxy at $z_s=2.93$ crossing the lensing caustic cast by the galaxy cluster SDSS J1226+2152 ($z_l=0.43$), using Hubble Space Telescope observations. We report in the arc several asymmetric surface brightness features whose angular separations are a fraction of an arcsecond from the lensing critical curve and appear to be highly but unequally magnified image pairs of underlying compact sources, with one brightest… 
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  • S. Birrer
  • Physics
    The Astrophysical Journal
  • 2021
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