Stability Threshold for flagging data after Self-Calibration.
For Self-calibration solutions with more than one iteration, the solution is flagged if the difference between the last two iterations exceeds Threshold times the expected phase error due to noise.
The default is 0, a convention indicating to ignore this flagging step.
When the noise level is appropriately estimated, a Threshold of 3 is a good value to suppress unstable solutions that reflect some issues in the self-calibration model.