Optimizing Simulation Parameters for Weak Lensing Analyses Involving Non-Gaussian Observables
Abstract
We performed a series of numerical experiments to quantify the sensitivity of the predictions for weak lensing statistics obtained in ray-tracing dark matter (DM)-only simulations, to two hyper-parameters that influence the accuracy as well as the computational cost of the predictions: the thickness of the lens planes used to build past light cones and the mass resolution of the underlying DM simulation. The statistics considered are the power spectrum (PS) and a series of non-Gaussian observables, including the one-point probability density function, lensing peaks, and Minkowski functionals. Counterintuitively, we find that using thin lens planes (< 60 h-1 Mpc on a 240 h-1 Mpc simulation box) suppresses the PS over a broad range of scales beyond what would be acceptable for a survey comparable to the Large Synoptic Survey Telescope (LSST). A mass resolution of 7.2 × 1011 h-1 M⊙ per DM particle (or 2563 particles in a (240 h-1 Mpc)3 box) is sufficient to extract information using the PS and non-Gaussian statistics from weak lensing data at angular scales down to 1' with LSST-like levels of shape noise.
- Publication:
-
The Astronomical Journal
- Pub Date:
- June 2020
- DOI:
- 10.3847/1538-3881/ab8f8c
- arXiv:
- arXiv:1909.12345
- Bibcode:
- 2020AJ....159..284Z
- Keywords:
-
- Weak gravitational lensing;
- Large-scale structure of the universe;
- Computational methods;
- 1797;
- 902;
- 1965;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 17 pages, 10 figures, accepted to ApJ