Speaker
Des Small
Description
When combining signals from separate antennas to do interferometry, we focus our observation on a phase centre by applying appropriate delays based on a geometric and atmospheric model. However, the atmosphere isn't perfectly predictable, and signal chains may also introduce delays. In order to be able to average down data for imaging and other analysis we need to calibrate out residual delays by fringe fitting. Building on the Radio Interferometry Measurement Equation, this lecture will explain the theory and the practice of fringefitting in CASA.
