.. _rotation: Including Rotation ================== This section discusses how to include the effects of rotation in GYRE calculations. See the :ref:`osc-rot` section for further details of GYRE's rotation treatment. Setting the Rotation Rate ------------------------- There are two different ways to define the rotation angular frequency :math:`\Orot`, via parameters in the :nml_g:`rot` namelist group. * If :nml_n:`Omega_rot_source` = :nml_v:`'MODEL'`, then differential rotation is assumed with a spatially varying :math:`\Orot` obtained from the stellar model. If the model doesn't have this capability (see the :ref:`model-caps` section), then :math:`\Orot` is set to zero throughout the star. * If :nml_n:`Omega_rot_source` = :nml_v:`'UNIFORM'`, then uniform rotation is assumed with a spatially constant :math:`\Orot` set by the :nml_n:`Omega_rot` and :nml_n:`Omega_rot_units` parameters. Incorporating Doppler Effects ----------------------------- The :ref:`osc-rot-doppler` effect is incorporated automatically whenever calculations are performed with non-zero :math:`\Orot` and mode azimuthal order :math:`m`. To disable this effect, set :nml_n:`m`\ = :nml_v:`0` in the :nml_g:`mode` namelist group. Incorporating Coriolis Effects ------------------------------ Incorporating the effects of the Coriolis force can be done using a :ref:`perturbative treatment ` or a :ref:`non-perturbative treatment `. In the former case the effects are be applied as a post-calculation correction to non-rotating eigenfrequencies (see the :nml_v:`domega_rot` output item in the :ref:`summary-files` and :ref:`detail-files` sections). In the latter case, the traditional approximation of rotation (TAR) can be enabled by setting :nml_n:`coriolis_method`\ =\ :nml_v:`'TAR'` in the :nml_g:`rot` namelist group. The :ref:`TAR solution family ` is controlled by the :nml_n:`rossby` parameter of the :nml_g:`rot` namelist group; set to :nml_v:`.TRUE.` for the Rossby family, and to :nml_v:`.FALSE.` for the gravito-acoustic family.