$\kappa$TNG: Effect of Baryonic Processes on Weak Lensing with IllustrisTNG Simulations
Abstract
We study the effect of baryonic processes on weak lensing (WL) observables with a suite of mock WL maps, the $\kappa$TNG, based on the cosmological hydrodynamic simulations IllustrisTNG. We quantify the baryonic effects on the WL angular power spectrum, onepoint probability distribution function (PDF), and number counts of peaks and minima. We also show the redshift evolution of the effects, which is a key to distinguish the effect of baryons from fundamental physics such as dark energy, dark matter, and massive neutrinos. We find that baryonic processes reduce the smallscale power, suppress the tails of the PDF, peak and minimum counts, and change the total number of peaks and minima. We compare our results to existing semianalytic models and hydrodynamic simulations, and discuss the source of discrepancies. The $\kappa$TNG suite includes 10,000 realisations of $5 \times 5 \, \mathrm{deg}^2$ maps for 40 source redshifts up to $z_s = 2.6$, well covering the range of interest for existing and upcoming weak lensing surveys. We also produce the $\kappa$TNGDark suite of maps, generated based on the corresponding dark matter only IllustrisTNG simulations. Our mock maps are suitable for developing analytic models that incorporate the effect of baryons, but also particularly useful for studies that rely on mass maps, such as nonGaussian statistics and machine learning with convolutional neural networks. The suite of mock maps is publicly available at Columbia Lensing (www.columbialensing.org).
 Publication:

arXiv eprints
 Pub Date:
 October 2020
 arXiv:
 arXiv:2010.09731
 Bibcode:
 2020arXiv201009731O
 Keywords:

 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 10 pages, 7 figures, 3 tables, submitted to MNRAS, data available at http://columbialensing.org/