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In the version of RAMSES after RUM 2017 (PR #284 and after), new blocks were introduced instead of one large &PHYSICS_PARAMS:
Cooling parameters
The block named &COOLING_PARAMS contains the parameters related to cooling / basic chemistry
| Variable name | Fortran type | Default value | Description |
|---|---|---|---|
cooling |
boolean |
.false. |
Enable gas atomic & metal cooling |
metal |
logical |
.false. |
Enable metals advection (requires 1 hydro variable) |
isothermal |
logical |
.false. |
(deprecated) Enable equation of state for gas (heating and cooling disabled if .true.) |
barotropic_eos |
logical |
.false. |
Enable barotropic equation of state for gas (heating and cooling disabled if .true.). Replaced 'isothermal' |
barotropic_eos_form |
string |
legacy |
Type of barotropic EOS. Options: isothermal, polytrope, double_polytrope, custom, legacy |
polytrope_rho |
real |
1.0d50 | sets rho0 in EOS (density normalisation or knee-density), in g/cm3 |
polytrope_index |
real |
1.0d0 | sets gamma in EOS (polytropic index) |
T_eos |
real |
10 | sets T0 in EOS (isothermal temperature or temperature normalisation), in K |
mu_gas |
real |
1d0 | molecular weight |
haardt_madau |
logical |
.false. |
Enable UV background |
J21 |
real |
0.0 | UV flux at threshold in 10^21 units |
a_spec |
real |
1.0 | Slope of the UV spectrum |
self_shielding |
logical |
.false. |
Enable self-shielding for densities above 0.01 g.cm^-3 |
z_ave |
real |
0.0 | Initial average metal abundance |
z_reion |
real |
8.5 | Reionization redshift (UV background disabled for higher redshifts) |
ind_rsink |
real |
4.0 | Number of cells defining the radius of the sphere where AGN feedback is active |
T2max |
real |
HUGE | Temperature ceiling for gas heating (heating ceiling if isothermal=.false.) |
neq_chem |
logical |
.false. |
Enable non-equilibrium chemistry |
Star formation parameters
The block named &SF_PARAMS contains the parameters related to star formation
| Variable name | Fortran type | Default value | Description |
|---|---|---|---|
m_star |
real |
-1.0 | Star particle mass in units of mass_sph |
n_star |
real |
0.1 | Star formation density threshold in H/cc |
T2_star |
real |
0.0 | Typical ISM polytropic temperature (cooling floor if isothermal=.false.) |
g_star |
real |
1.6 | Typical ISM polytropic index (cooling floor if isothermal=.false.) |
del_star |
real |
2D2 | Star formation density threshold in critical density (cosmo=.true. only) |
eps_star |
real |
0.0 | Star formation efficiency |
jeans_ncells |
real |
-1.0 | Jeans polytropic equation of state (cooling floor if isothermal=.false.) |
sf_virial |
logical |
.false. |
Enable turbulent star formation prescriptions (requires 1 hydro variable) |
sf_trelax |
real |
0.0 | Relaxation time for star formation (cosmo=.false. only) |
sf_tdiss |
real |
0.0 | Dissipation timescale for subgrid turbulence in units of turbulent crossing time (sf_virial=.true. only) |
sf_model |
integer |
3 | Turbulent star formation model (sf_virial=.true. only) |
sf_log_properties |
logical |
.false. |
Output gas properties of cells undergoing a star particle birth or supernova event |
sf_compressive |
logical |
.false. |
Store and advect the compressive and solenoidal turbulent field in two different hydro variables (sf_virial=.true. only) |
Feedback parameters
The block named &FEEDBACK_PARAMS contains the parameters related to cooling / basic chemistry
| Variable name | Fortran type | Default value | Description |
|---|---|---|---|
eta_sn |
real |
0.0 | Supernova mass fraction |
eta_ssn |
real |
0.95 | Single supernova ejected mass fraction (sf_imf=.true. only) |
t_sne |
real |
10.0 | Supernova blast time in Myr |
delayed_cooling |
logical |
.false. |
Enable delayed cooling through passive energy scalar advection (requires 1 hydro variable) |
t_diss |
real |
20.0 | Dissipation timescale for supernova feedback in Myr (delayed_cooling=.true. only) |
yield |
real |
0.0 | Supernova metal yield |
mass_gmc |
real |
0.0 | Stochastic exploding GMC mass in solar mass |
kappa_IR |
real |
0.0 | IR dust opacity for supernova feedback |
f_ek |
real |
0.0 | Supernova kinetic energy fraction (only between 0 and 1) |
f_w |
real |
0.0 | Supernova mass loading factor (f_ek>0 only) |
rbubble |
real |
0.0 | Supernova superbubble radius in pc (f_ek>0 only) |
ndebris |
integer |
1 | Supernova debris particle number (f_ek>0 only) |
mass_star_max |
real |
120.0 | Maximum mass of a star to undergo a supernova with eta_ssn efficiency in solar mass (sf_imf=.true. only) |
mass_sne_min |
real |
10.0 | Minimum mass of a star to undergo a supernova blast in solar mass (sf_imf=.true. only) |
ir_feedback |
logical |
.false. |
Enable IR feedback from accreting sink particles |
ir_eff |
real |
0.75 | Efficiency of the IR feedback on sink particles (ir_feedback=.true.only) |
Units parameters
The block named &UNITS_PARAMS contains the parameters related to units that are set "by hand" (cosmo=.false. only!).
| Variable name | Fortran type | Default value | Description |
|---|---|---|---|
units_density |
real |
1.0 | Density unit in cgs (only for cosmo=.false., requires G=1) |
units_time |
real |
1.0 | Time unit in cgs (only for cosmo=.false., requires G=1) |
units_length |
real |
1.0 | Length unit in cgs (only for cosmo=.false., requires G=1) |
GRACKLE parameters
Additionally, if the code has been compiled with GRACKLE=1 in the Makefile and properly linked against the hdf5 and grackle libraries, it is possible to define a &GRACKLE_PARAMS block to control the grackle parameters.
Please visit https://grackle.readthedocs.io/en/grackle-3.0/Parameters.html for a more extensive description of the grackle parameters.
| Variable name | Fortran type | Default value | Description |
|---|---|---|---|
use_grackle |
integer |
1 | Activate Grackle |
grackle_with_radiative_cooling |
integer |
1 | Include radiative cooling |
grackle_primordial_chemistry |
integer |
0 | Primordial chemistry flag |
grackle_metal_cooling |
integer |
0 | Enable metal cooling using Cloudy tables |
grackle_UVbackground |
integer |
0 | Enable UV background |
grackle_cmb_temperature_floor |
integer |
1 | Enable effective CMB temperature floor |
grackle_h2_on_dust |
integer |
0 | Enable H2 formation on dust grains |
grackle_photoelectric_heating |
integer |
0 | Enable a spatially uniform heating term approximating photo-electric heating |
grackle_use_volumetric_heating_rate |
integer |
0 | Signal that an array of volumetric heating rates is being provided |
grackle_use_specific_heating_rate |
integer |
0 | Signal that an array of specific heating rates is being provided |
grackle_three_body_rate |
integer |
0 | Flag to control which three-body H2 formation rate is used |
grackle_cie_cooling |
integer |
0 | Enable H2 collision-induced emission cooling |
grackle_h2_optical_depth_approximation |
integer |
0 | Enable H2 cooling attenuation |
grackle_ih2co |
integer |
1 | |
grackle_ipiht |
integer |
1 | |
grackle_NumberOfTemperatureBins |
integer |
600 | |
grackle_CaseBRecombination |
integer |
0 | |
grackle_Compton_xray_heating |
integer |
0 | Flag to enable Compton heating from an X-ray background |
grackle_LWbackground_sawtooth_suppression |
integer |
0 | Flag to enable suppression of Lyman-Werner flux due to Lyman-series absorption |
grackle_NumberOfDustTemperatureBins |
integer |
250 | |
grackle_use_radiative_transfer |
integer |
0 | Signal that arrays of ionization and heating rates from radiative transfer solutions are being provided |
grackle_radiative_transfer_coupled_rate_solver |
integer |
0 | Flag that must be enabled to couple the passed radiative transfer fields to the chemistry solver |
grackle_radiative_transfer_intermediate_step |
integer |
0 | Flag to enable intermediate stepping in applying radiative transfer fields to chemistry solver |
grackle_radiative_transfer_hydrogen_only |
integer |
0 | Flag to only use hydrogen ionization and heating rates from the radiative transfer solutions |
grackle_self_shielding_method |
integer |
0 | Switch to enable approximate self-shielding from the UV background |
grackle_Gamma |
real |
5./3. | The ratio of specific heats for an ideal gas |
grackle_photoelectric_heating_rate |
real |
8.5D-26 | The heating rate in units of erg cm-3 s-1 |
grackle_HydrogenFractionByMass |
real |
0.76 | |
grackle_DeuteriumToHydrogenRatio |
real |
2.0*3.4e-5 | |
grackle_SolarMetalFractionByMass |
real |
0.01295 | |
grackle_TemperatureStart |
real |
1.0 | |
grackle_TemperatureEnd |
real |
1.0D9 | |
grackle_DustTemperatureStart |
real |
1.0 | |
grackle_DustTemperatureEnd |
real |
1500. | |
grackle_LWbackground_intensity |
real |
0.0 | Intensity of a constant Lyman-Werner H2 photo-dissociating radiation field in units of 10-21 erg s-1 cm-2 Hz-1 sr-1 |
grackle_UVbackground_redshift_on |
real |
7.0 | |
grackle_UVbackground_redshift_off |
real |
0.0 | |
grackle_UVbackground_redshift_fullon |
real |
6.0 | |
grackle_UVbackground_redshift_drop |
real |
0.0 | |
grackle_cloudy_electron_fraction_factor |
real |
9.153959D-3 | |
grackle_data_file |
character |
Path to the data file containing the metal cooling and UV background HDF5 tables |
Physics parameters (LEGACY ONLY)
The block named &PHYSICS_PARAMS contains the parameters related to physical models.
| Variable name | Fortran type | Default value | Description |
|---|---|---|---|
units_density |
real |
1.0 | Density unit in cgs (only for cosmo=.false., requires G=1) |
units_time |
real |
1.0 | Time unit in cgs (only for cosmo=.false., requires G=1) |
units_length |
real |
1.0 | Length unit in cgs (only for cosmo=.false., requires G=1) |
cooling |
boolean |
.false. |
Enable gas atomic & metal cooling |
isothermal |
logical |
.false. |
Enable equation of state for gas (heating and cooling disabled if .true.) |
metal |
logical |
.false. |
Enable metals advection (requires 1 hydro variable) |
haardt_madau |
logical |
.false. |
Enable UV background |
self_shielding |
logical |
.false. |
Enable self-shielding for densities above 0.01 g.cm^-3 |
smbh |
logical |
.false. |
Enable super massive black holes for sink particles |
agn |
logical |
.false. |
Enable AGN feedback from super massive black holes |
neq_chem |
logical |
.false. |
Enable non-equilibrium chemistry |
ir_feedback |
logical |
.false. |
Enable IR feedback from accreting sink particles |
sf_virial |
logical |
.false. |
Enable turbulent star formation prescriptions (requires 1 hydro variable) |
sf_compressive |
logical |
.false. |
Store and advect the compressive and solenoidal turbulent field in two different hydro variables (sf_virial=.true. only) |
sf_log_properties |
logical |
.false. |
Output gas properties of cells undergoing a star particle birth or supernova event |
delayed_cooling |
logical |
.false. |
Enable delayed cooling through passive energy scalar advection (requires 1 hydro variable) |
sf_imf |
logical |
.false. |
Model Initial Mass Function during thermal feedback events |
T2_star |
real |
0.0 | Typical ISM polytropic temperature (cooling floor if isothermal=.false.) |
g_star |
real |
1.6 | Typical ISM polytropic index (cooling floor if isothermal=.false.) |
jeans_ncells |
real |
-1.0 | Jeans polytropic equation of state (cooling floor if isothermal=.false.) |
T2max |
real |
1D50 | Temperature ceiling for gas heating (heating ceiling if isothermal=.false.) |
n_star |
real |
0.1 | Star formation density threshold in H/cc |
m_star |
real |
-1.0 | Star particle mass in units of mass_sph |
del_star |
real |
2D2 | Star formation density threshold in critical density (cosmo=.true. only) |
eps_star |
real |
0.0 | Star formation efficiency |
t_star |
real |
0.0 | Star formation time scale in Gyr (only used if eps_star>0) |
sf_trelax |
real |
0.0 | Relaxation time for star formation (cosmo=.false. only) |
sf_tdiss |
real |
0.0 | Dissipation timescale for subgrid turbulence in units of turbulent crossing time (sf_virial=.true. only) |
sf_model |
integer |
3 | Turbulent star formation model (sf_virial=.true. only) |
eta_sn |
real |
0.0 | Supernova mass fraction |
eta_ssn |
real |
0.95 | Single supernova ejected mass fraction (sf_imf=.true. only) |
t_sne |
real |
10.0 | Supernova blast time in Myr |
t_diss |
real |
20.0 | Dissipation timescale for supernova feedback in Myr (delayed_cooling=.true. only) |
yield |
real |
0.0 | Supernova metal yield |
mass_gmc |
real |
0.0 | Stochastic exploding GMC mass in solar mass |
kappa_IR |
real |
0.0 | IR dust opacity for supernova feedback |
f_ek |
real |
0.0 | Supernova kinetic energy fraction (only between 0 and 1) |
f_w |
real |
0.0 | Supernova mass loading factor (f_ek>0 only) |
rbubble |
real |
0.0 | Supernova superbubble radius in pc (f_ek>0 only) |
ndebris |
integer |
1 | Supernova debris particle number (f_ek>0 only) |
mass_star_max |
real |
120.0 | Maximum mass of a star to undergo a supernova with eta_ssn efficiency in solar mass (sf_imf=.true. only) |
mass_sne_min |
real |
10.0 | Minimum mass of a star to undergo a supernova blast in solar mass (sf_imf=.true. only) |
J21 |
real |
0.0 | UV flux at threshold in 10^21 units |
a_spec |
real |
1.0 | Slope of the UV spectrum |
z_ave |
real |
0.0 | Initial average metal abundance |
z_reion |
real |
8.5 | Reionization redshift (UV background disabled for higher redshifts) |
ind_rsink |
real |
4.0 | Number of cells defining the radius of the sphere where AGN feedback is active |
ir_eff |
real |
0.75 | Efficiency of the IR feedback on sink particles (ir_feedback=.true.only) |
Updated