2015/06/03 by Peter Behroozi, Alexander Knebe, F. R. Pearce +11 · 75 citations
Physics and Astronomy · #Accretion (finance) #Astronomy #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics #Cluster (spacecraft) #Computer science #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Halo effect #Physics #Redshift #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stv2046
published in Monthly Notices of the Royal Astronomical Society 454(3), 3020-3029 (Oxford University Press) · Figs. 2, 4, and 7 show the main issues. This project was initiated at the Subhaloes Going Notts conference (http://popia.ft.uam.es/SubhaloesGoingNotts/Home.html). MNRAS submitted
arxiv created 2015/06/03 · openalex publication_date 2015/10/17 · arxiv updated 2015/10/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Merging haloes with similar masses (i.e. major mergers) pose significant challenges for halo finders. We compare five halo-finding algorithms’ (ahf, hbt, rockstar, subfind, and velociraptor) recovery of halo properties for both isolated and cosmological major mergers. We find that halo positions and velocities are often robust, but mass biases exist for every technique. The algorithms also show strong disagreement in the prevalence and duration of major mergers, especially at high redshifts (z > 1). This raises significant uncertainties for theoretical models that require major mergers for, e.g. galaxy morphology changes, size changes, or black hole growth, as well as for finding Bullet Cluster analogues. All finders not using temporal information also show host halo and subhalo relationship swaps over successive timesteps, requiring careful merger tree construction to avoid problematic mass accretion histories. We suggest that future algorithms should combine phase-space and temporal information to avoid the issues presented.