[daip] aips fringe fitting

[Eric Greisen]

Cao Hongmin wrote:
> 
> 
> Hi Eric,
> 
> when doing fringe fitting, we can choose to solve "phase","delay",and 
> "rate",
> 
> but i am confused about the "phase" noted above.
> 
> The error of the interferometer phase can be expressed as:
> 
> 
> so the "phase" solved by aips task "fring" means the in the above 
> fomula, or something else?
> 
> thanks for the helps,
> 
> hongmin

As you can probably see - all math symbols are missing from your e-mail 
so I cannot examine your question.  The interferometer phase is all that 
we measure.  If there is a delay error, the phase will be A + f * d 
where A is a frequency independent value, f is the frequency and d the 
delay error.  FRING puts a phase correction into the SN table to attempt 
to bring all IFs to the same phase after application of the delay 
correction it determines.  The rate part is used when it is found that d 
varies with time and corrects for changes between the times at which d 
is measured.

Eric Greisen