Gravitational Lensing by a Massive Object in a Dark Matter Halo. II. Shear, Phase, and Image Geometry

  title={Gravitational Lensing by a Massive Object in a Dark Matter Halo. II. Shear, Phase, and Image Geometry},
  author={Michal Karamazov and David Heyrovsk{\'y}},
  journal={The Astrophysical Journal},
We study the gravitational lensing influence of a massive object in a dark matter halo, using a simple model of a point mass embedded in a spherical Navarro–Frenk–White halo. Building on the analysis of critical curves and caustics presented in the first part of this work, we proceed to explore the geometry of images formed by the lens. First, we analyze several lensing quantities including shear, phase, and their weak-lensing approximations, illustrating the results with image-plane maps. We… 
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  • M. Oguri
  • Physics
    Publications of the Astronomical Society of the Pacific
  • 2021
We present a new approach for fast calculation of gravitational lensing properties, including the lens potential, deflection angles, convergence, and shear, of elliptical Navarro–Frenk–White (NFW)