diff --git a/doc/RTD/source/SubgridModels/EAGLE/index.rst b/doc/RTD/source/SubgridModels/EAGLE/index.rst index 0587f3f2e0f5295d1eab91ef53f902e8757c0b77..a4069bda593204af1fb977e14ca57f5db157ee49 100644 --- a/doc/RTD/source/SubgridModels/EAGLE/index.rst +++ b/doc/RTD/source/SubgridModels/EAGLE/index.rst @@ -62,12 +62,21 @@ EAGLE run, that section of the parameter file reads: Jeans_density_threshold_H_p_cm3: 0.1 # 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: 8000 # 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 + Jeans_gamma_effective: 1.3333333 # Slope 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: 8000 # Temperature of the EAGLE Cool limiter entropy floor at the density threshold, expressed in Kelvin. - Cool_gamma_effective: 1. # Slope the of the EAGLE Cool limiter entropy floor - + Cool_gamma_effective: 1. # Slope of the EAGLE Cool limiter entropy floor + +SWIFT will convert the temperature normalisations and Hydrogen number +density thresholds into internal energies and densities respectively +assuming a neutral gas with primoridal abundance pattern. This implies +that the floor may not be exactly at the position given in the YAML +file if the gas has different properties. This is especially the case +for the temperature limit which will often be lower than the imposed +floor by a factor :math:`\frac{\mu_{\rm neutral}}{\mu_{ionised}} +\approx \frac{1.22}{0.59} \approx 2` due to the different ionisation +states of the gas. Note that the model only makes sense if the ``Cool`` threshold is at a lower density than the ``Jeans`` threshold.