Zooming by in the CARPoolGP lane: new CAMELS-TNG simulations of zoomed-in massive halos

TL;DR

This paper introduces CARPoolGP, a novel method for efficiently exploring high-dimensional parameter spaces in cosmological simulations, demonstrated on an extended CAMELS suite of zoom-in simulations of massive halos, with applications to astrophysical parameter forecasting.

Contribution

The paper presents CARPoolGP, a new sampling and emulation technique that reduces variance and computational cost in high-dimensional galaxy formation models, and extends CAMELS with 768 zoom-in simulations of massive halos.

Findings

CARPoolGP effectively explores high-dimensional parameter spaces.

Extended CAMELS suite includes 768 zoom-in simulations of massive halos.

Emulation of Y-M relation improves future SZ observation forecasts.

Abstract

Galaxy formation models within cosmological hydrodynamical simulations contain numerous parameters with non-trivial influences over the resulting properties of simulated cosmic structures and galaxy populations. It is computationally challenging to sample these high dimensional parameter spaces with simulations, particularly for halos in the high-mass end of the mass function. In this work, we develop a novel sampling and reduced variance regression method, CARPoolGP, which leverages built-in correlations between samples in different locations of high dimensional parameter spaces to provide an efficient way to explore parameter space and generate low variance emulations of summary statistics. We use this method to extend the Cosmology and Astrophysics with MachinE Learning Simulations (CAMELS) to include a set of 768 zoom-in simulations of halos in the mass range of $10^{13} - 10^{14.5} M_\odot\,h^{-1}$ that span a 28-dimensional parameter space in the IllustrisTNG model. With these simulations and the CARPoolGP emulation method, we explore parameter trends in the Compton $Y-M$, black hole mass-halo mass, and metallicity-mass relations, as well as thermodynamic profiles and quenched fractions of satellite galaxies. We use these emulations to provide a physical picture of the complex interplay between supernova and active galactic nuclei feedback. We then use emulations of the $Y-M$ relation of massive halos to perform Fisher forecasts on astrophysical parameters for future Sunyaev-Zeldovich observations and find a significant improvement in forecasted constraints. We publicly release both the simulation suite and CARPoolGP software package.