Set of scripts to quickly calculate proper motions for astronomical masers.
This pipeline is intended for VLBI maser positions derived from interferometric software such as AIPS and CASA. The input data sets used as example is the tables generated by SAD in AIPS. #See AIPS website here. #See CASA website here.
The pipeline consists of 4 scripts:
- region-identification.py An interactive plot to identify regions of proper motion. Specifically regions from which to average individual maser spots (data points identified by gaussian fitting) to maser features (averages of maser spots in regions which are thought to be the same gas cloud). The script plots all the epochs of the maser spots, and gives interactive controls for zoom, panning and to select regions which should be averaged to calculate proper motions.
- relative_pm.py A script which reduces maser spots to maser features and then calculates the relative proper motions using linear regression fitting. The script takes the output of region-identification.py as input and generates a textfile of maser features and proper motions.
- pm_corrections.py (TODO) An optional script which corrects for parralax, galactic rotation and the motion of the reference maser if possible or required.
- pm_flagging.py (TODO) A script which flags proper motions based on user specified criteria.