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Feature comparison
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This page gives an overview of the features that StORM supports and for which cases you might want to use other oscillation codes.

Input data
==========

StORM currently only supports the `GSM <https://gyre.readthedocs.io/en/stable/ref-guide/stellar-models/gsm-file-format.html>`_ format. If you have other stellar model formats that you want to use with StORM, see if `tomso <https://tomso.readthedocs.io/en/stable/>`_ is able to import the format you have and convert it to a GSM. While StORM might be able to read more types of models in the future, this is currently a low priority given tools such as tomso exist.

Included physics
================

StORM only solves the adiabatic pulsation equations [#eqn]_ with the vacuum boundary conditions [#boundary]_. Any form of energy transport through radiation, conduction, ... is ignored.

Rotation is included on various levels. A more detailed explanation can be `found here <rotation>`_. In short, StORM does the following:

- The main solver includes terms for the Coriolis acceleration up to first order
- Toroidal mode coupling in a perturbative way
- Stellar deformation and resulting mode coupling in a perturbative way

The radial order determination is done with `Eckart-Scuflaire-Osaki-Takata <https://ui.adsabs.harvard.edu/abs/2006PASJ...58..893T/abstract>`_ scheme.

Some features you might want, but are not supported
===================================================

- Automatic regridding in case the stellar model resolution is low (manually increasing the number of points is supported as part of the ``input`` command)
- Non-adiabatic calculations
- Full 2D stellar models (e.g. such as done by ACOR and TOP) and pulsation calculations
- Traditional approximation of rotation for high-order g modes with rotation
- Effects of magnetic fields

These features may be supported in the future.

.. [#eqn] Derivations for the adiabatic pulsation equations can be found in `various <https://ui.adsabs.harvard.edu/abs/2010aste.book.....A/abstract>`_ `textbooks <https://ui.adsabs.harvard.edu/abs/1989nos..book.....U/abstract>`_. An overview of the equations can be found in the `GYRE documentation <https://gyre.readthedocs.io/en/stable/ref-guide/osc-equations.html>`_. Note that StORM uses a modified form of the equations to partial include the effect of the Coriolis force in the main solver, similar to `Soufi et al. (1998) <https://ui.adsabs.harvard.edu/abs/1998A&A...334..911S>`_. Validation of the results can be found in ``maxima/oscillation-equations.mac``.
.. [#boundary] This assumes that the pressure goes to zero near the surface of the star. Should the density not go to zero, the outer boundary is treated as having a density discontinuity, immediately dropping to zero outside the star.