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Detailed Mass Map of CL0024+1654 from Strong Lensing

J. Anthony Tyson·Greg P. Kochanski·Ian P. Dell'Antonio
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Abstract

We construct a high resolution mass map of the z=0.39 cluster 0024+1654, based on parametric inversion of the associated gravitational lens. The lens creates eight well-resolved sub-images of a background galaxy, seen in deep imaging with HST. Excluding mass concentrations centered on visible galaxies, more than 98% of the remaining mass is represented by a smooth concentration of dark matter centered near the brightest cluster galaxies, with a 35 h^{-1} kpc soft core. The asymmetry in the mass distribution is <3% inside 107 ~h^{-1} kpc radius. The dark matter distribution we observe in CL0024 is far more smooth, symmetric, and nonsingular than in typical simulated clusters in either Omega=1 or Omega=0.3 CDM cosmologies. Integrated to 107 h^{-1} kpc radius, the rest-frame mass to light ratio is M/L_V = 276\pm 40 h (M/L_V)_solar.

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J. Anthony Tyson, Greg P. Kochanski, Ian P. Dell'Antonio. 1998-05-02. Detailed Mass Map of CL0024+1654 from Strong Lensing. https://doi.org/10.1086/311314

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