[evlatests] Antenna 13 baseline

[Craig Walker]

We've spent a lot of time in the past trying to relate the VLA and VLBI 
(ITRF) systems.  The longitude we now use for conversions is 107.617988.
That number is derived by forcing a match between the baseline longitude 
of the N8 to Pie Town baselines derived by the VLA baseline solution and 
by VLBI geodesy.


Also recall that, last I heard, the VLA system did not use the official 
speed of light (recall it is now defined).  I don't think this matters 
because the baselines are actually used in ns, but it is a bit odd.

Cheers,

Craig


Ken Sowinski wrote:
> Rick reported:
> 
>>    The `AIPS-approved' changes,  in METERS, are:
>>
>>    Delta Bx = 0.15 
>>    Delta By = 0.22 
>>    Delta Bz = 0.50
>>
>>    It would be useful to put these into the Modcomps, and see if the
>>phase rate slows down, or doubles ...
> 
> 
> These offsets have been rotated to the longitude of Greenwich,
> 107.617222 degrees (chose your sign), and applied to the EVLA 
> position parameters for the master pad.
> Delta Bx = +0.16 m
> Delta By = -0.21
> Delta Bz = +0.50
> 
> They were also converted to ns and applied to the VLA baseline
> file to keep the two systems consistent.
> Delta Bx = +0.50 ns
> Delta By = +0.73
> Delta Bz = +1.67
> 
> _______________________________________________
> evlatests mailing list
> evlatests at listmgr.cv.nrao.edu
> http://listmgr.cv.nrao.edu/mailman/listinfo/evlatests


-- 
---------------------------------------------------------------------
     R. Craig Walker            Array Operations Center
     cwalker at nrao.edu           National Radio Astronomy Observatory
     Phone  505 835 7247        P. O. Box O
     Fax    505 835 7027        Socorro NM 87801   USA
---------------------------------------------------------------------