CoLoRe: fast cosmological realisations over large volumes with multiple tracers

TL;DR

CoLoRe is a versatile software tool that efficiently generates large-scale synthetic cosmological survey data, supporting multiple tracers and various levels of physical accuracy for comprehensive analysis and systematics studies.

Contribution

It introduces a flexible, fast, and publicly available software package capable of simulating multi-tracer cosmological surveys with different accuracy levels.

Findings

Accurately reproduces theoretical predictions of cosmological maps.

Successfully simulates multi-survey datasets including DESI, LSST, and SKA.

Demonstrates utility in systematics characterization and covariance estimation.

Abstract

We present CoLoRe, a public software package to efficiently generate synthetic realisations of multiple cosmological surveys. CoLoRe can simulate the growth of structure with different degrees of accuracy, with the current implementation supporting lognormal fields, first, and second order Lagrangian perturbation theory. CoLoRe simulates the density field on an all-sky light-cone up to a desired maximum redshift, and uses it to generate multiple 2D and 3D maps: galaxy positions and velocities, lensing (shear, magnification, convergence), integrated Sachs-Wolfe effect, line intensity mapping, and line of sight skewers for simulations of the Lyman-$\alpha$ forest. We test the accuracy of the simulated maps against analytical theoretical predictions, and showcase its performance with a multi-survey simulation including DESI galaxies and quasars, LSST galaxies and lensing, and SKA intensity mapping and radio galaxies. We expect CoLoRe to be particularly useful in studies aiming to characterise the impact of systematics in multi-experiment analyses, quantify the covariance between different datasets, and test cross-correlation pipelines for near-future surveys.