The accuracy of weak lensing simulations

  title={The accuracy of weak lensing simulations},
  author={Stefan Hilbert and Alexandre Barreira and Giulio Fabbian and Pablo Fosalba and Carlo Giocoli and Sownak Bose and Matteo Calabrese and Carmelita Carbone and Christopher T. Davies and Baojiu Li and Claudio Llinares and Pierluigi Monaco},
  journal={Monthly Notices of the Royal Astronomical Society},
We investigate the accuracy of weak lensing simulations by comparing the results of five independently developed lensing simulation codes run on the same input N-body simulation. Our comparison focuses on the lensing convergence maps produced by the codes, and in particular on the corresponding PDFs, power spectra, and peak counts. We find that the convergence power spectra of the lensing codes agree to $\lesssim 2{{\ \rm per\ cent}}$ out to scales ℓ ≈ 4000. For lensing peak counts, the… 

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