Cheng-Zong Ruan is a postdoctoral fellow at the Institute of Theoretical Astrophysics, University of Oslo. Photo: ITA/UiO.
Cosmic voids (regions of low galaxy density) provide extra cosmological information beyond that obtained from galaxy clustering. The streaming model describes the mapping between real and redshift space for clustering statistics.
This talk presents a simulation-based streaming model for the redshift space void-galaxy correlation. To capture the cosmological dependence, we trained neural-network emulators for the model ingredients — void-galaxy position and velocity statistics — on a suite of N-body simulations. The model accurately reproduces the redshift space multipoles (monopole and quadrupole) measured from N-body simulations.
In the end, we discuss the requirements for pushing this method to data from future DESI and Euclid data.
The underlining matter density field in modern cosmological simulations. Low-density voids (dark blue regions) are surrounded by galaxies which form in high-density regions (orange/white). Void-galaxy cross-correlation provides extra cosmological information beyond the traditional galaxy auto-correlation probes. Credits: the IllustrisTNG collaboration (https://www.tng-project.org/media/)
