SOAP: A Python Package for Calculating the Properties of Galaxies and Halos Formed in Cosmological Simulations

TL;DR

SOAP is a Python package that efficiently computes detailed properties of galaxies and halos from cosmological simulation data, supporting multiple definitions and parallel processing for large datasets.

Contribution

We introduce SOAP, a versatile Python tool that enables consistent, parallel analysis of galaxy and halo properties across various simulation types and halo definitions.

Findings

Supports multiple halo definitions including spherical overdensities and fixed apertures.

Provides parallel processing capabilities for large datasets.

Compatible with dark matter-only and hydrodynamic simulations.

Abstract

Modern large scale cosmological hydrodynamic simulations require robust tools capable of analysing their data outputs in a parallel and efficient manner. We introduce SOAP (Spherical Overdensity and Aperture Processor), a Python package designed to compute halo and galaxy properties from SWIFT simulations after being post-processed with a subhalo finder. SOAP takes a subhalo catalogue as input and calculates a wide array of properties for each object. SOAP offers parallel processing capabilities via mpi4py for efficient handling of large datasets, and allows for consistent property calculation across multiple halo finders. SOAP supports various halo definitions, including spherical overdensities and fixed physical apertures, providing flexibility for diverse observational comparisons. The package is compatible with both dark matter-only and full hydrodynamic simulations, producing HDF5 catalogues that are integrated with the swiftsimio package for seamless unit handling.