[time-nuts] Result of Earth Quake speeds up earth?

[Magnus Danielson]

On 03/20/2011 08:26 PM, Bruce Griffiths wrote:
> The beam from the interferometer/phased array can be swept over the sky
> by varying the phase shift between the elements during the data
> reduction process allowing high resolution imaging.
> Compensating for Earth rotation and consequent changes in the
> atmospheric delay are necessary. Differential phase shifts of a few tens
> of picosec are significant in the imaging process.
> The effect of atmospheric refraction has to be accounted for if accurate
> positions of the source relative to the Earth's surface are required.

I would use cross-correlation between two (or more) antennas. The noise 
of the individual antenna assembly would cancel out for sufficient 
correlation length. That would help to boot-strap the direct correlation 
if not the FFTed correlation will do.

Long FFTs is cheap these days.

Then again, the real VLBI people would beat me up for such naive approaches.

Cheers,
Magnus