eagle_50.yml

# Define some meta-data about the simulation
MetaData:
  run_name:   EAGLE-L0050N0752-Ref

# Define the system of units to use internally. 
InternalUnitSystem:
  UnitMass_in_cgs:     1.98841e43    # 10^10 M_sun in grams
  UnitLength_in_cgs:   3.08567758e24 # Mpc in centimeters
  UnitVelocity_in_cgs: 1e5           # km/s in centimeters per second
  UnitCurrent_in_cgs:  1             # Amperes
  UnitTemp_in_cgs:     1             # Kelvin

# Cosmological parameters
Cosmology:
  h:              0.6777        # Reduced Hubble constant
  a_begin:        0.0078125     # Initial scale-factor of the simulation
  a_end:          1.0           # Final scale factor of the simulation
  Omega_m:        0.307         # Matter density parameter
  Omega_lambda:   0.693         # Dark-energy density parameter
  Omega_b:        0.0482519     # Baryon density parameter

# Parameters governing the time integration
TimeIntegration:
  dt_min:     1e-10 # The minimal time-step size of the simulation (in internal units).
  dt_max:     1e-2  # The maximal time-step size of the simulation (in internal units).
  
# Parameters governing the snapshots
Snapshots:
  basename:            eagle # Common part of the name of output files
  output_list_on:      1
  output_list:         ./output_list.txt

# Parameters governing the conserved quantities statistics
Statistics:
  delta_time:           1.02
  scale_factor_first:   0.05

# Parameters for the self-gravity scheme
Gravity:
  eta:                         0.025     # Constant dimensionless multiplier for time integration.
  MAC:                         geometric # Use the geometric opening angle condition
  theta_cr:                    0.7       # Opening angle (Multipole acceptance criterion)
  use_tree_below_softening:    0
  mesh_side_length:            256
  comoving_DM_softening:         0.003320 # Comoving softening for DM (3.32 ckpc)
  max_physical_DM_softening:     0.001300 # Physical softening for DM (1.30 pkpc)
  comoving_baryon_softening:     0.001790 # Comoving softening for baryons (1.79 ckpc)
  max_physical_baryon_softening: 0.000700 # Physical softening for baryons (0.70 pkpc)

# Parameters for the hydrodynamics scheme
SPH:
  resolution_eta:                    1.2348   # Target smoothing length in units of the mean inter-particle separation (1.2348 == 48Ngbs with the cubic spline kernel).
  h_min_ratio:                       0.1      # Minimal smoothing length in units of softening.
  h_max:                             0.5      # Maximal smoothing length in co-moving internal units.
  CFL_condition:                     0.2      # Courant-Friedrich-Levy condition for time integration.
  minimal_temperature:               100.0    # (internal units)
  initial_temperature:               268.7    # (internal units)
  particle_splitting:                1        # Particle splitting is ON
  particle_splitting_mass_threshold: 7e-4     # (internal units, i.e. 7e6 Msun ~ 4x initial gas particle mass)

# Parameters of the stars neighbour search
Stars:
  resolution_eta:        1.1642   # Target smoothing length in units of the mean inter-particle separation
  h_tolerance:           7e-3

# Parameters for the Friends-Of-Friends algorithm
FOF:
  basename:                        fof_output  # Filename for the FOF outputs.
  min_group_size:                  256         # The minimum no. of particles required for a group.
  linking_length_ratio:            0.2         # Linking length in units of the main inter-particle separation.
  black_hole_seed_halo_mass_Msun:  1.5e10      # Minimal halo mass in which to seed a black hole (in solar masses).
  scale_factor_first:              0.05        # Scale-factor of first FoF black hole seeding calls.
  delta_time:                      1.00751     # Scale-factor ratio between consecutive FoF black hole seeding calls.

Scheduler:
  max_top_level_cells:   32
  tasks_per_cell:        5
  cell_split_size:       200
  
Restarts:
  onexit:       1
  delta_hours:  6.0

# Parameters related to the initial conditions
InitialConditions:
  file_name:  EAGLE_L0050N0752_ICs.hdf5
  periodic:   1
  cleanup_h_factors: 1               # Remove the h-factors inherited from Gadget
  cleanup_velocity_factors: 1        # Remove the sqrt(a) factor in the velocities inherited from Gadget
  generate_gas_in_ics: 1             # Generate gas particles from the DM-only ICs
  cleanup_smoothing_lengths: 1       # Since we generate gas, make use of the (expensive) cleaning-up procedure.

# Parameters of the line-of-sight outputs
LineOfSight:
  basename:            eagle_los
  num_along_x:         0
  num_along_y:         0
  num_along_z:         100
  scale_factor_first:  0.1
  delta_time:          1.1

# Impose primoridal metallicity
EAGLEChemistry:
  init_abundance_metal:     0.
  init_abundance_Hydrogen:  0.752
  init_abundance_Helium:    0.248
  init_abundance_Carbon:    0.0
  init_abundance_Nitrogen:  0.0
  init_abundance_Oxygen:    0.0
  init_abundance_Neon:      0.0
  init_abundance_Magnesium: 0.0
  init_abundance_Silicon:   0.0
  init_abundance_Iron:      0.0

# EAGLE cooling parameters
EAGLECooling:
  dir_name:                ./coolingtables/
  H_reion_z:               7.5                 # Planck 2018
  H_reion_eV_p_H:          2.0
  He_reion_z_centre:       3.5
  He_reion_z_sigma:        0.5
  He_reion_eV_p_H:         2.0

# COLIBRE cooling parameters
COLIBRECooling:
  dir_name:                ./UV_dust1_CR1_G1_shield1.hdf5 # Location of the cooling tables
  H_reion_z:               7.5               # Redshift of Hydrogen re-ionization (Planck 2018)
  H_reion_eV_p_H:          2.0
  He_reion_z_centre:       3.5               # Redshift of the centre of the Helium re-ionization Gaussian
  He_reion_z_sigma:        0.5               # Spread in redshift of the  Helium re-ionization Gaussian
  He_reion_eV_p_H:         2.0               # Energy inject by Helium re-ionization in electron-volt per Hydrogen atom
  delta_logTEOS_subgrid_properties: 0.3      # delta log T above the EOS below which the subgrid properties use Teq assumption
  rapid_cooling_threshold:          0.333333 # Switch to rapid cooling regime for dt / t_cool above this threshold.

# EAGLE star formation parameters
EAGLEStarFormation:
  EOS_density_norm_H_p_cm3:          0.1       # Physical density used for the normalisation of the EOS assumed for the star-forming gas in Hydrogen atoms per cm^3.
  EOS_temperature_norm_K:            8000      # Temperature om the polytropic EOS assumed for star-forming gas at the density normalisation in Kelvin.
  EOS_gamma_effective:               1.3333333 # Slope the of the polytropic EOS assumed for the star-forming gas.
  KS_normalisation:                  1.515e-4  # The normalization of the Kennicutt-Schmidt law in Msun / kpc^2 / yr.
  KS_exponent:                       1.4       # The exponent of the Kennicutt-Schmidt law.
  min_over_density:                  57.7      # The over-density above which star-formation is allowed.
  KS_high_density_threshold_H_p_cm3: 1e3       # Hydrogen number density above which the Kennicut-Schmidt law changes slope in Hydrogen atoms per cm^3.
  KS_high_density_exponent:          2.0       # Slope of the Kennicut-Schmidt law above the high-density threshold.
  EOS_entropy_margin_dex:            0.3       # Logarithm base 10 of the maximal entropy above the EOS at which stars can form.
  threshold_norm_H_p_cm3:            0.1       # Normalisation of the metal-dependant density threshold for star formation in Hydrogen atoms per cm^3.
  threshold_Z0:                      0.002     # Reference metallicity (metal mass fraction) for the metal-dependant threshold for star formation.
  threshold_slope:                   -0.64     # Slope of the metal-dependant star formation threshold
  threshold_max_density_H_p_cm3:     10.0      # Maximal density of the metal-dependant density threshold for star formation in Hydrogen atoms per cm^3.
  
# Parameters for the EAGLE "equation of state"
EAGLEEntropyFloor:
  Jeans_density_threshold_H_p_cm3: 1e-4      # Physical density above which the EAGLE Jeans limiter entropy floor kicks in expressed in Hydrogen atoms per cm^3.
  Jeans_over_density_threshold:    10.       # Overdensity above which the EAGLE Jeans limiter entropy floor can kick in.
  Jeans_temperature_norm_K:        800       # Temperature of the EAGLE Jeans limiter entropy floor at the density threshold expressed in Kelvin.
  Jeans_gamma_effective:           1.3333333 # Slope the of the EAGLE Jeans limiter entropy floor
  Cool_density_threshold_H_p_cm3: 1e-5       # Physical density above which the EAGLE Cool limiter entropy floor kicks in expressed in Hydrogen atoms per cm^3.
  Cool_over_density_threshold:    10.        # Overdensity above which the EAGLE Cool limiter entropy floor can kick in.
  Cool_temperature_norm_K:        10.        # Temperature of the EAGLE Cool limiter entropy floor at the density threshold expressed in Kelvin. (NOTE: This is below the min T and hence this floor does nothing)
  Cool_gamma_effective:           1.         # Slope the of the EAGLE Cool limiter entropy floor

# EAGLE feedback model
EAGLEFeedback:
  use_SNII_feedback:                1               # Global switch for SNII thermal (stochastic) feedback.
  use_SNIa_feedback:                1               # Global switch for SNIa thermal (continuous) feedback.
  use_AGB_enrichment:               1               # Global switch for enrichement from AGB stars.
  use_SNII_enrichment:              1               # Global switch for enrichement from SNII stars.
  use_SNIa_enrichment:              1               # Global switch for enrichement from SNIa stars.
  filename:                         ./yieldtables/  # Path to the directory containing the EAGLE yield tables.
  IMF_min_mass_Msun:                0.1             # Minimal stellar mass considered for the Chabrier IMF in solar masses.
  IMF_max_mass_Msun:              100.0             # Maximal stellar mass considered for the Chabrier IMF in solar masses.
  SNII_min_mass_Msun:               8.0             # Minimal mass considered for SNII stars in solar masses.
  SNII_max_mass_Msun:             100.0             # Maximal mass considered for SNII stars in solar masses.
  SNII_sampled_delay:               1               # Sample the SNII lifetimes to do feedback.
  SNII_delta_T_K:                   3.16228e7       # Change in temperature to apply to the gas particle in a SNII thermal feedback event in Kelvin.
  SNII_energy_erg:                  1.0e51          # Energy of one SNII explosion in ergs.
  SNII_energy_fraction_min:         0.3             # Minimal fraction of energy applied in a SNII feedback event.
  SNII_energy_fraction_max:         3.0             # Maximal fraction of energy applied in a SNII feedback event.
  SNII_energy_fraction_Z_0:         0.0012663729    # Pivot point for the metallicity dependance of the SNII energy fraction (metal mass fraction).
  SNII_energy_fraction_n_0_H_p_cm3: 1.4588          # Pivot point for the birth density dependance of the SNII energy fraction in cm^-3.
  SNII_energy_fraction_n_Z:         0.8686          # Power-law for the metallicity dependance of the SNII energy fraction.
  SNII_energy_fraction_n_n:         0.8686          # Power-law for the birth density dependance of the SNII energy fraction.
  SNIa_DTD:                         Exponential     # Functional form of the SNIa delay time distribution.
  SNIa_DTD_delay_Gyr:               0.04            # Stellar age after which SNIa start in Gyr (40 Myr corresponds to stars ~ 8 Msun).
  SNIa_DTD_exp_timescale_Gyr:       2.0             # Time-scale of the exponential decay of the SNIa rates in Gyr.
  SNIa_DTD_exp_norm_p_Msun:         0.002           # Normalisation of the SNIa rates in inverse solar masses.
  SNIa_energy_erg:                 1.0e51           # Energy of one SNIa explosion in ergs.
  AGB_ejecta_velocity_km_p_s:      10.0             # Velocity of the AGB ejectas in km/s.
  stellar_evolution_age_cut_Gyr:    0.1             # Stellar age in Gyr above which the enrichment is down-sampled.
  stellar_evolution_sampling_rate:   10             # Number of time-steps in-between two enrichment events for a star above the age threshold.
  SNII_yield_factor_Hydrogen:       1.0             # (Optional) Correction factor to apply to the Hydrogen yield from the SNII channel.
  SNII_yield_factor_Helium:         1.0             # (Optional) Correction factor to apply to the Helium yield from the SNII channel.
  SNII_yield_factor_Carbon:         0.5             # (Optional) Correction factor to apply to the Carbon yield from the SNII channel.
  SNII_yield_factor_Nitrogen:       1.0             # (Optional) Correction factor to apply to the Nitrogen yield from the SNII channel.
  SNII_yield_factor_Oxygen:         1.0             # (Optional) Correction factor to apply to the Oxygen yield from the SNII channel.
  SNII_yield_factor_Neon:           1.0             # (Optional) Correction factor to apply to the Neon yield from the SNII channel.
  SNII_yield_factor_Magnesium:      2.0             # (Optional) Correction factor to apply to the Magnesium yield from the SNII channel.
  SNII_yield_factor_Silicon:        1.0             # (Optional) Correction factor to apply to the Silicon yield from the SNII channel.
  SNII_yield_factor_Iron:           0.5             # (Optional) Correction factor to apply to the Iron yield from the SNII channel.

# EAGLE AGN model
EAGLEAGN:
  subgrid_seed_mass_Msun:             1.5e5      # Black hole subgrid mass at creation time in solar masses.
  multi_phase_bondi:                  0          # Compute Bondi rates per neighbour particle?
  with_angmom_limiter:                1          # Are we applying the Rosas-Guevara et al. (2015) viscous time-scale reduction term?
  viscous_alpha:                      1e6        # Normalisation constant of the viscous time-scale in the accretion reduction term
  radiative_efficiency:               0.1        # Fraction of the accreted mass that gets radiated.
  max_eddington_fraction:             1.         # Maximal allowed accretion rate in units of the Eddington rate.
  eddington_fraction_for_recording:   0.1        # Record the last time BHs reached an Eddington ratio above this threshold.
  coupling_efficiency:                0.15       # Fraction of the radiated energy that couples to the gas in feedback events.
  AGN_delta_T_K:                      3.16228e8  # Change in temperature to apply to the gas particle in an AGN feedback event in Kelvin.
  AGN_num_ngb_to_heat:                1.         # Target number of gas neighbours to heat in an AGN feedback event.
  max_reposition_mass:                2e8        # Maximal BH mass considered for BH repositioning in solar masses.
  max_reposition_distance_ratio:      3.0        # Maximal distance a BH can be repositioned, in units of the softening length.
  with_reposition_velocity_threshold: 1          # Should we only reposition to particles that move slowly w.r.t. the black hole?
  max_reposition_velocity_ratio:      0.5        # Maximal velocity offset of a particle to reposition a BH to, in units of the ambient sound speed of the BH. Only meaningful if with_reposition_velocity_ratio is 1.
  min_reposition_velocity_threshold: -1.0        # Minimal value of the velocity threshold for repositioning [km/s], set to < 0 for no effect. Only meaningful if with_reposition_velocity_ratio is 1.
  set_reposition_speed:               0          # Should we reposition black holes with (at most) a prescribed speed towards the potential minimum?
  threshold_major_merger:             0.333      # Mass ratio threshold to consider a BH merger as 'major'
  threshold_minor_merger:             0.1        # Mass ratio threshold to consider a BH merger as 'minor'
  merger_threshold_type:              2          # Type of velocity threshold for BH mergers (0: v_circ at kernel edge, 1: v_esc at actual distance, with softening, 2: v_esc at actual distance, no softening).
  merger_max_distance_ratio:          3.0        # Maximal distance over which two BHs can merge, in units of the softening length.