diff --git a/src/cooling.c b/src/cooling.c
index 376373ad80e1d784f183eecafbe51d20a80b3159..793f22ec15825a2eb781886dc6ed1fc92e0874c2 100644
--- a/src/cooling.c
+++ b/src/cooling.c
@@ -67,7 +67,7 @@ void cooling_struct_dump(const struct cooling_function_data* cooling,
}
/**
- * @brief Restore a hydro_props struct from the given FILE as a stream of
+ * @brief Restore a cooling_function struct from the given FILE as a stream of
* bytes.
*
* @param cooling the struct
diff --git a/src/entropy_floor.h b/src/entropy_floor.h
index c03f2ff5db714d984e2a7d851546751cbb6d3139..e65d55b2ab51047748403ee690edd7cb361eda1d 100644
--- a/src/entropy_floor.h
+++ b/src/entropy_floor.h
@@ -35,4 +35,3 @@
#endif
#endif /* SWIFT_ENTROPY_FLOOR_H */
-
diff --git a/src/entropy_floor/EAGLE/entropy_floor.h b/src/entropy_floor/EAGLE/entropy_floor.h
index 0260eb85090fda03735429f7797a563642c13f46..55316ebcb6239dabf32ec9a5c70718245d111a94 100644
--- a/src/entropy_floor/EAGLE/entropy_floor.h
+++ b/src/entropy_floor/EAGLE/entropy_floor.h
@@ -19,10 +19,217 @@
#ifndef SWIFT_ENTROPY_FLOOR_EAGLE_H
#define SWIFT_ENTROPY_FLOOR_EAGLE_H
+#include "adiabatic_index.h"
+#include "cosmology.h"
+#include "hydro_properties.h"
+#include "parser.h"
+#include "units.h"
+
/**
* @file src/entropy_floor/EAGLE/entropy_floor.h
* @brief Entropy floor used in the EAGLE model
*/
+/**
+ * @brief Properties of the entropy floor in the EAGLE model.
+ */
+struct entropy_floor_properties {
+
+ /*! Density threshold for the Jeans floor in Hydrogen atoms per cubic cm */
+ float Jeans_density_threshold_H_p_cm3;
+
+ /*! Density threshold for the Jeans floor in internal units */
+ float Jeans_density_threshold;
+
+ /*! Inverse of the density threshold for the Jeans floor in internal units */
+ float Jeans_density_threshold_inv;
+
+ /*! Over-density threshold for the Jeans floor */
+ float Jeans_over_density_threshold;
+
+ /*! Slope of the Jeans floor power-law */
+ float Jeans_gamma_effective;
+
+ /*! Temperature of the Jeans floor at the density threshold in Kelvin */
+ float Jeans_temperature_norm_K;
+
+ /*! Temperature of the Jeans floor at the density thresh. in internal units */
+ float Jeans_temperature_norm;
+
+ /*! Pressure of the Jeans floor at the density thresh. in internal units */
+ float Jeans_pressure_norm;
+
+ /*! Density threshold for the Cool floor in Hydrogen atoms per cubic cm */
+ float Cool_density_threshold_H_p_cm3;
+
+ /*! Density threshold for the Cool floor in internal units */
+ float Cool_density_threshold;
+
+ /*! Inverse of the density threshold for the Cool floor in internal units */
+ float Cool_density_threshold_inv;
+
+ /*! Over-density threshold for the Cool floor */
+ float Cool_over_density_threshold;
+
+ /*! Slope of the Cool floor power-law */
+ float Cool_gamma_effective;
+
+ /*! Temperature of the Cool floor at the density threshold in Kelvin */
+ float Cool_temperature_norm_K;
+
+ /*! Temperature of the Cool floor at the density thresh. in internal units */
+ float Cool_temperature_norm;
+
+ /*! Pressure of the Cool floor at the density thresh. in internal units */
+ float Cool_pressure_norm;
+};
+
+/**
+ * @brief Compute the entropy floor of a given #part.
+ *
+ * Note that the particle is not updated!!
+ *
+ * @param p The #part.
+ * @param cosmo The cosmological model.
+ * @param props The properties of the entropy floor.
+ */
+float entropy_floor(const struct part *p, const struct cosmology *cosmo,
+ const struct entropy_floor_properties *props) {
+
+ /* Physical density in internal units */
+ const float rho = hydro_get_physical_density(p, cosmo);
+
+ /* Critical density at this redshift.
+ * Recall that this is 0 in a non-cosmological run */
+ const float rho_crit = cosmo->critical_density;
+
+ float pressure = 0.;
+
+ /* Are we in the regime of the Jeans equation of state? */
+ if ((rho > rho_crit * props->Jeans_over_density_threshold) &&
+ (rho > props->Jeans_density_threshold)) {
+
+ const float pressure_Jeans = props->Jeans_pressure_norm *
+ powf(rho * props->Jeans_density_threshold_inv,
+ props->Jeans_gamma_effective);
+
+ pressure = max(pressure, pressure_Jeans);
+ }
+
+ /* Are we in the regime of the Cool equation of state? */
+ if ((rho > rho_crit * props->Cool_over_density_threshold) &&
+ (rho > props->Cool_density_threshold)) {
+
+ const float pressure_Cool = props->Cool_pressure_norm *
+ powf(rho * props->Cool_density_threshold_inv,
+ props->Cool_gamma_effective);
+
+ pressure = max(pressure, pressure_Cool);
+ }
+
+ /* Convert to an entropy.
+ * (Recall that the entropy is the same in co-moving and phycial frames) */
+ return gas_entropy_from_pressure(rho, pressure);
+}
+
+/**
+ * @brief Initialise the entropy floor by reading the parameters and converting
+ * to internal units.
+ *
+ * @param params The YAML parameter file.
+ * @param us The system of units used internally.
+ * @param phys_cont The physical constants.
+ * @param props The entropy floor properties to fill.
+ */
+void entropy_floor_init(struct swift_params *params,
+ const struct unit_system *us,
+ const struct phys_const *phys_const,
+ const struct hydro_props *hydro_props,
+ struct entropy_floor_properties *props) {
+
+ /* Read the parameters in the units they are set */
+ props->Jeans_density_threshold_H_p_cm3 = parser_get_param_float(
+ params, "EAGLEEntropyFloor:Jeans_density_threshold_H_p_cm3");
+ props->Jeans_over_density_threshold = parser_get_param_float(
+ params, "EAGLEEntropyFloor:Jeans_over_density_threshold");
+ props->Jeans_temperature_norm_K = parser_get_param_float(
+ params, "EAGLEEntropyFloor:Jeans_temperature_norm_K");
+ props->Jeans_gamma_effective =
+ parser_get_param_float(params, "EAGLEEntropyFloor:Jeans_gamma_effective");
+
+ props->Cool_density_threshold_H_p_cm3 = parser_get_param_float(
+ params, "EAGLEEntropyFloor:Cool_density_threshold_H_p_cm3");
+ props->Cool_over_density_threshold = parser_get_param_float(
+ params, "EAGLEEntropyFloor:Cool_over_density_threshold");
+ props->Cool_temperature_norm_K = parser_get_param_float(
+ params, "EAGLEEntropyFloor:Cool_temperature_norm_K");
+ props->Cool_gamma_effective =
+ parser_get_param_float(params, "EAGLEEntropyFloor:Cool_gamma_effective");
+
+ /* Initial Hydrogen abundance (mass fraction) */
+ const float X_H = hydro_props->hydrogen_mass_fraction;
+
+ /* Now convert to internal units */
+ props->Jeans_temperature_norm =
+ props->Jeans_temperature_norm_K /
+ units_cgs_conversion_factor(us, UNIT_CONV_TEMPERATURE);
+ props->Jeans_density_threshold =
+ props->Jeans_density_threshold /
+ units_cgs_conversion_factor(us, UNIT_CONV_VOLUME) *
+ phys_const->const_proton_mass / X_H;
+
+ props->Cool_temperature_norm =
+ props->Cool_temperature_norm_K /
+ units_cgs_conversion_factor(us, UNIT_CONV_TEMPERATURE);
+ props->Cool_density_threshold =
+ props->Cool_density_threshold /
+ units_cgs_conversion_factor(us, UNIT_CONV_VOLUME) *
+ phys_const->const_proton_mass / X_H;
+
+ /* We assume neutral gas */
+ const float mean_molecular_weight = hydro_props->mu_neutral;
+
+ /* Get the common terms */
+ props->Jeans_density_threshold_inv = 1.f / props->Jeans_density_threshold;
+ props->Cool_density_threshold_inv = 1.f / props->Cool_density_threshold;
+
+ /* P_norm = (k_B * T) / (m_p * mu) * rho_threshold */
+ props->Jeans_pressure_norm =
+ (phys_const->const_boltzmann_k * props->Jeans_temperature_norm) /
+ (phys_const->const_proton_mass * mean_molecular_weight) *
+ props->Jeans_density_threshold;
+
+ props->Cool_pressure_norm =
+ (phys_const->const_boltzmann_k * props->Cool_temperature_norm) /
+ (phys_const->const_proton_mass * mean_molecular_weight) *
+ props->Cool_density_threshold;
+}
+
+/**
+ * @brief Write an entropy floor struct to the given FILE as a stream of bytes.
+ *
+ * @param props the struct
+ * @param stream the file stream
+ */
+void entropy_floor_struct_dump(const struct entropy_floor_properties *props,
+ FILE *stream) {
+
+ restart_write_blocks((void *)props, sizeof(struct entropy_floor_properties),
+ 1, stream, "entropy floor", "entropy floor properties");
+}
+
+/**
+ * @brief Restore a entropy floor struct from the given FILE as a stream of
+ * bytes.
+ *
+ * @param props the struct
+ * @param stream the file stream
+ */
+void entropy_floor_struct_restore(struct entropy_floor_properties *props,
+ FILE *stream) {
+
+ restart_read_blocks((void *)props, sizeof(struct entropy_floor_properties), 1,
+ stream, NULL, "entropy floor properties");
+}
#endif /* SWIFT_ENTROPY_FLOOR_EAGLE_H */
diff --git a/src/entropy_floor/none/entropy_floor.h b/src/entropy_floor/none/entropy_floor.h
index 69412a44763e95e3413f9f711c9e2d826c580ab0..16cf4e66697d58ddc8107580f8bad34bc64ca744 100644
--- a/src/entropy_floor/none/entropy_floor.h
+++ b/src/entropy_floor/none/entropy_floor.h
@@ -25,5 +25,4 @@
* floors.
*/
-
#endif /* SWIFT_ENTROPY_FLOOR_NONE_H */
diff --git a/src/runner.c b/src/runner.c
index 7befd7a60c3440704b7f57023a666f3d0c250d4e..83ae4b72bb3a3380e634f89e8da9507b55f60074 100644
--- a/src/runner.c
+++ b/src/runner.c
@@ -48,6 +48,7 @@
#include "debug.h"
#include "drift.h"
#include "engine.h"
+#include "entropy_floor.h"
#include "error.h"
#include "gravity.h"
#include "hydro.h"