Gas Kinematic Position Angle Data Product
Changes between DR2 and DR3
This dataproduct was not part of DR2.
Gas kinematic position angle
The gas kinematic measurements are described in detail in Emission Line Data products Section 3.1. The position angle (PA) of the gas rotation was measured from the two-dimensional 1st component gas velocity kinematic maps on all spaxels that pass the quality cut for the Velocity measurements ($Vel_{error}<30$ km/s). We use the FIT_KINEMATIC_PA code that is based on the method described in Appendix C of Krajnovic et al. (2006). The kinematic PA was measured with an assumed centre of the map at (25.5,25.5). FIT_KINEMATIC_PA calculates a 3-sigma uncertainty which can maximally become 90 degrees. Because we provide a 1-sigma uncertainty in this catalog, the maximum uncertainty PA_GASKIN_ERR is 30 degrees. The kinematic PA is measured anticlockwise, with 0 degrees being North on the sky.
We do not provide safe usage criteria as it will depend on the specific science case. Please note that these gas kinematic PAs have not been subjected to rigorous quality control checks. We recommend to use them with caution.
The catalog parameters are:
PA_STELKIN | Kinematic position angle
PA_STELKIN_ERR | 1-sigma error on the kinematic position angle