NOCTUA Stellar Evolution ======================== .. warning:: This module is currently work in progress. All features should be considered experimental for now! Framework for stellar evolution and feedback in idealised and cosmological zoom-in simulations Usage ----- Designed to be used in conjunction with the chemistry module :doc:`modules_sgchem`, the star formation module :doc:`modules_sf_ecogal` and the supernova-feedback module :doc:`modules_sne`. This module enables normalized advection of 10 scalar fields, corresponding to :math:`\mathrm{H,\ He,\ C,\ N,\ O,\ Ne,\ Mg,\ Si,\ Fe,\ X}`, where :math:`\mathrm{X}` is a placeholder for all other metals. These fields are coupled to the chemistry module through the SGCHEM_VARIABLE_Z switch. Ionic chemical species and molecules are also consistently advected with respect to the elemental abundances listed above. The dust content is also advected as a passive scalar, but for now no proper dust model is implemented. Data about the metal and dust abundances are saved to snapshot files to the fields ``Noctua_Metals``, ``Noctua_Metallicity`` and ``DusttoGasRatio``. Chemical enrichment occurs through stellar processes, using the star particles handled by SF_ECOGAL. For now, only enrichment due to core-collapse SNe is considered by this module, where the latter are handled by SNE. Additional Parameters --------------------- * ``YieldTable_SNII`` Path to the HDF5 table containing stellar yields as a function of stellar mass and metallicity. * ``InitialAbundancesMode`` Determines how the initial metal abundances are set, details are given below. **When NOCTUA_DUST_MODE = 0:** * ``InitialDustToGasRatio`` Sets the initial dust to gas ratio in the simulation, depending on the mode selected above. It is given relative to the value of the local ISM (as in SGCHEM). Currently, the d2g ratio will **not** evolve over time, so this is effectively a fixed value for the whole simulation. **When NOCTUA_DUST_MODE = 1:** * ``DustToMetalsRatio`` Sets the dust-to-metals ratio :math:`\beta_\mathrm{D2M}`. The scaling that is applied is the following, for each gas cell: :math:`\frac{\xi}{\xi_\odot} = \beta_\mathrm{D2M} \cdot \frac{Z}{Z_\odot}`, where :math:`\xi_\odot` is the dust to gas ratio in the local ISM. In other words, for ``DustToMetalsRatio=1.0``, the dust to gas ratio will scale to metallicity exactly, following the solar neighbourhood relation. Initial Abundances ^^^^^^^^^^^^^^^^^^ The following values are supported for ``InitialAbundancesMode``: * **(0)** A metallicity floor is applied to all elements beside hydrogen and helium, which for now is hard-coded to :math:`10^{-10}`. * **(1)** The values found in the IC file are used to initialise the fields. In this case, it is important to define the relevant datasets listed above in the HDF5 initial conditions file. * **(2)** The fields are set to scaled values of the solar abundances of Asplund et al. (2009), keeping the relative abundance patterns unchanged. Scaling is controlled through ``InitialMetallicityScaling``, where setting it to 1 would give exactly solar abundances. For all modes except **1**, the initial dust to gas ratio is set by the ``InitialDustToGasRatio`` parameter. Additional Config.sh Options ---------------------------- Main module switches ^^^^^^^^^^^^^^^^^^^^ NOCTUA_STELLAR_EVOLUTION Master switch used to enable stellar evolution and metal advection NOCTUA_DUST_MODE Sets how dust is handled by the module. Set to 0 to use a fixed dust-to-gas ratio across gas cells, and set to 1 to use a fixed dust-to-metals ratio (i.e. a scaling is then applied relative to the local gas metallicity, see description of relevant parameter above). Testing and debugging switches ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ NOCTUA_SKIP_MASS_INJECTION Do not return mass or inject yields in the event of a supernova (only inject energy) NOCTUA_TEST_IMF_CONVERGENCE Normalize the masses of yields by the mass of the star particle. Used to test convergence to the continuous IMF case. NOCTUA_OUTPUT_METAL_MASSES Save masses of individual metals to snapshot files. Useful only for debugging, in principle this is redundant with the mass fractions and gas mass. Authors ------- * Patrick Hirling (patrick.hirling@epfl.ch) Acknowledgements ---------------- Some aspects of this module, in particular the normalized metal advection, are based on the implementation of :doc:`modules_gfm`, with authorisation. Usage Policy and Citation ------------------------- Please contact the authors before using this code, so that we can avoid any unnecessary project overlap. Co-authorship on independent publications produced with the code are not necessary, although we are happy to actively collaborate with users of the code that are interested in doing so.