Evolutionary tracks for Steam Worlds

<h3>Evolutionary tracks from the Steam Worlds Evolution (SWE) model (Aguichine et al. 2025, in prep).</h3> <p>Link to manuscript: <a href="https://arxiv.org/abs/2412.17945" target="_blank" rel="noopener">https://arxiv.org/abs/2412.17945</a></p> <p><strong>Model summary:</strong><br>Earth-like core (32.5% iron-sulfur alloy, 67.5% mantle with Earth-like Fe/Si ratio)<br>Pure H2O envelope and pure H2O atmosphere connected at P_b = 1000 bar<br><br><strong>Parameters:</strong><br>ST: Stellar Type (M or G), for radiative transfer in the atmosphere<br>WMF: Water Mass Fraction, between 0.001 and 1<br>T_eq: Equilibrium temperature (K), between 500 K and 700 K<br>M_p: Planet mass (M_e), between 0.2 M_E and 20.0 M_E<br>Age: Host star age (Gyr), between 0.01 Gyr and 20 Gyr, assuming the planet formed at t_0 = 10 Myr (can be adjusted)<br><br><strong>Model outputs:</strong><br>R_b: Planet radius (R_E) at 1000 bar<br>R_b: Planet radius (R_E) at 20 mbar, pressure level where pure steam is opaque at 1 micron<br>R_b: Planet radius (R_E) at 1 &micro;bar, pressure level of aerosols/haze formation<br>T_b: Temperature (K) at 1000 bar)<br>T_int: Intrinsic temperature (K), nominal values are between 10 K and 400 K<br>s_env: Specific entropy of H2O in the envelope (in J/K/kg)<br>I/MR^2: Moment of inertia factor<br><br><strong>Sources of energy for the cooling, expressed as luminosities (in W):</strong><br>L_env: energy from the H2O envelope (thermal + gravitational)<br>L_rad: radiogenic heat produced in the core<br>L_core: thermal energy of the core<br>L_grav: gravitational energy of the core<br>u_tot: total energy of the planet (J), obtained by fully integrating thermal (cp*T*dm) and gravitational energy<br><br><br><strong>By construction:</strong><br>L_env + L_rad + L_core + L_grav = (4 * Pi * R_p**2) * (sigma_SB * T_int**4)<br>d u_tot / d t = -L_int + L_rad&nbsp;<br><br><strong>NB:</strong> The last line of each track represents an estimate of the time until "full exhaustion" (see paper for details).</p>