AHF halo catalogues, protohalo shape data, and merger tree cross-match files for CDM and WDM N-body cosmological simulations (L=25 Mpc/h, N=512^3)

This dataset contains the simulation data products generated for the study of tidal adaptive force softening and artificial fragmentation in cosmological N-body simulations, published as: Mostoghiu Paun R. A., Croton D., Power C., Knebe A., Ussing A. J., Duffy A. R. (2025). Tidal adaptive softening and artificial fragmentation in cosmological simulations. MNRAS 542, 735–746. https://doi.org/10.1093/mnras/staf1229 The data are also used as the basis for a machine learning spurious halo classifier, available at: [here: spurious_halo_classifier] --- Contents --- Four zip archives are provided: B25_N512_CDM_3LPT.zip AHF halo catalogues (*.AHF_halos) and protohalo shape files (SPHERICITY_ALL_INFO.*.hdf5) for cold dark matter (CDM) simulations across four configurations: z39_fixed, z39_adapt, z99_fixed, z99_adapt, corresponding to initial redshifts z_ini = 39 or 99 and fixed or tidal adaptive force softening. B25_N512_WDM_3LPT.zip Same structure as CDM, but for 1 keV warm dark matter (WDM) simulations. WDM_CDM_crossmatch.zip AHF MergerTree cross-correlation files (.croco format) with WDM haloes as primaries and CDM haloes as secondaries. Used as the source of spurious halo labels in the ML classification project. CDM_WDM_crossmatch.zip AHF MergerTree cross-correlation files with CDM haloes as primaries and WDM haloes as secondaries. Provided for completeness, they are not used in either the published paper or the ML project. Note: the crossmatch archives were produced specifically for the ML classification project and were not part of the analysis in Mostoghiu Paun et al. (2025). The paper's spurious halo identification relied on protohalo sphericity, not CDM–WDM counterpart matching. --- Simulation setup --- Gravity code: GIZMO (Hopkins 2015, 2017) Box size: L = 25 Mpc/h Resolution: 512^3 particles; m_p = 1e7 M_sun/h Cosmology: Planck18 (H_0=67.74, Omega_m=0.31, Flat LCDM) Initial conditions: 3LPT with MONOFONIC (Michaux et al. 2021) Initial redshifts: z_ini = 39 (late-start, preferred) and z_ini = 99 WDM model: 1 keV (Viel et al. 2005 transfer function) Softening schemes: fixed (eps = 1.22 kpc/h) and tidal adaptive (Hopkins et al. 2023, min eps = 122 pc/h) Halo finder: AHF (Gill et al. 2004; Knollmann & Knebe 2009) Merger trees: MERGERTREE (packaged with AHF)