Including Rotation

GYRE can partially include the Doppler and Coriolis effects arising from stellar rotation, as described in detail in the Rotation Effects section. Here, we briefly review the parameters that influence how these effects are calculated.

Setting the Rotation Rate

There are a number of different ways to define the rotation angular velocity \(\Omega\), via parameters in the &rot namelist group.

  • If Omega_rot_source = MODEL, then \(\Omega\) is obtained from the stellar model (for those model formats that include these data)
  • If Omega_rot_source = UNIFORM, then uniform rotation is assumed, with the spatially constant \(\Omega\) set by the Omega_rot and Omega_rot_units parameters

Enabling Doppler Effects

Doppler effects are enabled by default whenever calculations are performed with non-zero \(\Omega\) and mode azimuthal order \(m\). To disable these effects, set m= 0 in the &mode namelist group.

Enabling Coriolis Effects

Coriolis effects are disabled by default, but can be enabled using the traditional approximation of rotation (TAR) by setting coriolis_method='TAR' in the &rot namelist group. The solution family is controlled by the rossby parameter of the &rot namelist group; set to .TRUE. for the Rossby family, and to .FALSE. (the default) for the gravito-acoustic family.