Simulations

Specifications

This page contains the specification of the simulations in AbacusSummit. We tabulate the simulations below.

Simulation specifications are given a descriptive label, which is included in the simulation name:

• Base: this is our standard size, 6912³ particles in 2 Gpc/h.

• High: A box with 6x better mass resolution, 6300³ in 1 Gpc/h.

• Highbase: A 1 Gpc/h box with the base mass resolution.

• Huge: these are larger boxes run with 27x worse mass resolution.

• Hugebase: Re-runs of some 2 Gpc/h boxes with the same 27x worse mass resolution.

• Fixedbase: Simulations with the base mass resolution but fixed-amplitude initial conditions, 4096³ in 1.18 Gpc/h.

• Small: Simulations with base mass resolution but 1728³ particles in 0.5 Gpc/h.

Run-Time Products

Only a few of our simulations include the full timeslice output; we typically output only subsamples. The “Full Outputs” column in the simulations table below specifies the redshifts (if any) for which a simulation has full timeslices. This column refers to sets of redshifts using the following abbreviations:

• Full: z = 3.0, 2.5, 2.0, 1.7, 1.4, 1.1, 0.8, 0.5, 0.4, 0.3, 0.2, 0.1

• Partial: z = 2.5, 1.4, 0.8, 0.2

• Partial+HiZ: Adds z = 3.0, 2.0 to the Partial list

Subsamples of particles, with positions, velocities, ID numbers, and kernel density estimates, are typically provided at the same 12 redshifts as the Full list (see Data Products). CompaSO group finding is run at these redshifts as well as 21 others (see CompaSO Halo Finder).

Note

The 21 “secondary” redshifts are only approximate and may not match from simulation to simulation. We do not shorten the Abacus timestep to land exactly on these secondary redshifts as we do for the primary redshifts. Always use the redshift in the header, not the directory name.

The huge and hugebase sims have fewer group finding and subsample epochs.

Base sims and Huge sims have light-cone outputs; others do not.

A base simulation typically produces about 10 TB of subsampled output, and each output slice is another 4 TB above that.

Covariance (Small) Boxes

We ran 2000 small simulations in 500 Mpc/h at the base mass resolution, intended for studies of covariance matrices in periodic boundary conditions. These have particle subsample outputs at z = 1.4, 1.1, 0.8, 0.5, and 0.2, as well as halo finding at all redshifts >0.2. However, about 15% of these simulations crashed due to some unresolved issue, almost certainly uncorrelated with any property of the large-scale structure in the simulation. Some of the crashed ones still produced usable outputs at higher redshifts. We have chosen to present the 1883 that yielded outputs at z = 1.1; 1643 of these reached z = 0.2. The numbering between ph3000 and ph4999 will be irregular.

Simulations Table

The following is a complete listing of the AbacusSummit simulations. You can also download this table as a CSV file here.

The numbers in the “Cosm” column correspond to cosmologies in the Cosmologies Table.

The “PPD” column is the number of particles-per-dimension.

SimName	Cosm	Phase	PPD	Box (Mpc/h)	z_Final	Full Outputs	Notes
AbacusSummit_base_c000_ph000	000	000	6912	2000	0.1	Full	Planck2018 LCDM
AbacusSummit_base_c000_ph{001-005}	000	001-005	6912	2000	0.1	Partial+HiZ	Planck2018 LCDM
AbacusSummit_base_c000_ph{006-024}	000	006-024	6912	2000	0.1	none	Planck2018 LCDM
AbacusSummit_high_c000_ph100	000	100	6300	1000	0.1	Full	High-res LCDM, no lightcone
AbacusSummit_highbase_c000_ph100	000	100	3456	1000	0.1	Full	Base-res LCDM, no lightcone
AbacusSummit_huge_c000_ph201	000	201	8640	7500	0.1	1.4, 1.1, 0.8, 0.5, 0.2	Low-res LCDM, box-centered lightcone
AbacusSummit_huge_c000_ph202	000	202	8640	7500	0.1	1.4, 1.1, 0.8, 0.5, 0.2	Low-res LCDM, box-centered lightcone
AbacusSummit_hugebase_c000_ph{000-024}	000	000-024	2304	2000	0.1	1.4, 1.1, 0.8, 0.5, 0.2	Low-res match to base, no lightcone
AbacusSummit_fixedbase_c000_ph099	000	099	4096	1185	0.1	Full	Base-res LCDM, fixed amplitudes
AbacusSummit_fixedbase_c000_ph098	000	098	4096	1185	0.1	Full	Base-res LCDM, fixed amplitudes, inversion of phase 99
AbacusSummit_small_c000_ph{3000-4999}	000	3000-4999	1728	500	0.2	none	Covariance matrix set
AbacusSummit_base_c001_ph000	001	000	6912	2000	0.1	Partial+HiZ	Low omega_c
AbacusSummit_base_c001_ph{001-005}	001	001-005	6912	2000	0.1	Partial	Low omega_c
AbacusSummit_base_c002_ph000	002	000	6912	2000	0.1	Partial+HiZ	wCDM with thawing model w0 = -0.7, wa = -0.5
AbacusSummit_base_c002_ph{001-005}	002	001-005	6912	2000	0.1	Partial	wCDM with thawing model w0 = -0.7, wa = -0.5
AbacusSummit_base_c003_ph000	003	000	6912	2000	0.1	Partial+HiZ	Neff=3.70, from base_nnu_plikHM_TT_lowl_lowE_Riess18_post_BAO
AbacusSummit_base_c003_ph{001-005}	003	001-005	6912	2000	0.1	Partial	Neff=3.70, from base_nnu_plikHM_TT_lowl_lowE_Riess18_post_BAO
AbacusSummit_base_c004_ph000	004	000	6912	2000	0.1	Partial+HiZ	Low sigma8_matter = 0.75, otherwise Baseline LCDM
AbacusSummit_base_c004_ph{001-005}	004	001-005	6912	2000	0.1	Partial	Low sigma8_matter = 0.75, otherwise Baseline LCDM
AbacusSummit_fixedbase_c{001-004}_ph099	001-005	099	4096	1185	0.1	Partial	Base-res LCDM, fixed amplitudes
AbacusSummit_base_c009_ph000	009	000	6912	2000	0.1	Partial	Baseline LCDM with massless neutrinos
AbacusSummit_base_c010_ph000	010	000	6912	2000	0.1	none	AbacusCosmos LCDM
AbacusSummit_base_c012_ph000	012	000	6912	2000	0.1	none	Euclid Flagship1
AbacusSummit_base_c013_ph000	013	000	6912	2000	0.1	none	Euclid Flagship2
AbacusSummit_base_c014_ph000	014	000	6912	2000	0.1	none	OuterRim
AbacusSummit_base_c015_ph000	015	000	6912	2000	0.1	none	Dark Sky
AbacusSummit_base_c016_ph000	016	000	6912	2000	0.1	none	Horizon
AbacusSummit_base_c017_ph000	017	000	6912	2000	0.1	none	Illustris
AbacusSummit_base_c018_ph000	018	000	6912	2000	0.1	none	Multidark Planck
AbacusSummit_base_c019_ph000	019	000	6912	2000	0.1	none	Baseline LCDM w/2 massive neutrino species
AbacusSummit_base_c020_ph000	020	000	6912	2000	0.1	none	Baseline LCDM with massless neutrinos
AbacusSummit_highbase_c021_ph000	021	000	3456	1000	0.1	Partial	MassiveNUs with massless neutrinos
AbacusSummit_highbase_c022_ph000	022	000	3456	1000	0.1	Partial	MassiveNUs w/1 massive 0.1 eV neutrino species
AbacusSummit_base_c{100-115}_ph000	100-115	000	6912	2000	0.1	none	Linear Derivative Grid
AbacusSummit_base_c116_ph000	116	000	6912	2000	0.1	none	Linear Derivative Grid
AbacusSummit_base_c{117-126}_ph000	117-126	000	6912	2000	0.1	none	Linear Derivative Grid
AbacusSummit_base_c{130-181}_ph000	130-181	000	6912	2000	0.1	none	Broader Emulator Grid

Missing Data

In the course of running AbacusSummit, a few rare instances of irreversible data loss occurred before the data could be archived. The resulting inhomogeneities in the data products presented by AbacusSummit are recorded here.

• AbacusSummit_base_c103_ph000, for redshifts 0.8 and above, is missing all field particles and all halo RVs (but not halo PIDs). Consequently, the halo cleaning is not present at redshift 0.8 and above.

• AbacusSummit_base_c004_ph003 is missing full (pack9) time slice outputs for redshifts 0.8 and 1.4. And, as a result, no time slice power spectra exist for those redshifts (AB power spectra exist as normal).

• AbacusSummit_base_c163_ph000 is missing some light cone files; some step files are missing, and within step files, some ranks’ outputs may be missing. The light cone should probably be treated as corrupt and unusable, although a manifest of all the files that survived to be merged into the ASDF data products is available under AbacusSummit_base_c163_ph000/lightcones/lcfiles.txt.

• AbacusSummit_base_c102_ph000 is missing all light cone step files except LightCone0 for steps 991 and later. Within those step files, it is unknown if outputs from particular ranks are missing. The light cone should probably be treated as corrupt and unusable.