Detection of Dark Matter Skewness in the VIRMOS-DESCART Survey: Implications for Ω0

  title={Detection of Dark Matter Skewness in the VIRMOS-DESCART Survey: Implications for $\Omega$0},
  author={Ue-li Pen and Tong-Jie Zhang and Ludovic van Waerbeke and Yannick Mellier and Pengjie Zhang and John Dubinski},
  journal={The Astrophysical Journal},
Weak gravitational lensing provides a direct statistical measure of dark matter distribution. The variance is easiest to measure, which constrains the degenerate product σ8Ω. The degeneracy is broken by measuring the skewness arising from the fact that densities must remain positive, which is not possible when the initially symmetric perturbations become nonlinear. Skewness measures the nonlinear mass scale, which in combination with the variance measures Ω0 directly. We present the first… 

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