[alma-config]"Chajnantor South" coordinates

[Bryan Butler]

simon,

there are at least 5 different coordinates floating around for
"Chajnantor South".  let me state unequivocally that the _true_
position is:

627807 E, 7453229 N

i leave off the decimal places because they are not meaningful in the
context of antenna placement.

the genesis of the positions is as follows:

 - the position given in ALMA memo 338 is: 627750, 7453100
   this position was derived entirely by looking only at the digital
   topography maps - i.e., no "ground truth" was involved.  it was,
   as you will recall, statistically, the center of the best area
   in that flat region.

 - the first surveyed position was staked during our site campaign in
   november 1999.  this was obtained from rough in-field modification
   of some preliminary analysis i had done similar to what went into
   memo 338.  the coordinates of this position are: 627749 E, 7453181 N;
   obtained from a hand-held GPS.

 - during that same site campaign, angel and i drove around the "Chajnantor
   North", "Chajnantor South", "Chajnantor East", "Chajnantor West", and
   "Pampa La Bola" possible center locations, and modified the locations
   of the centers to match more realistically what was the center of the
   "flat & smooth" part - for "Chajnantor South", this involved moving it
   about 100 meters to the east.  the new location for "Chajnantor South"
   obtained in that way was: 627822 E, 7453192 N; via hand-held GPS.

 - during that same site campaign, the guys from u. antofagasta came out
   with the differential GPS and measured the modified "Chajnantor South"
   location properly and accurately, and got: 627807 E, 7453229 N.  this
   is the *correct* "Chajnantor South" location.  this is referenced either
   to the oso/chalmers mast or the higesa marker (one was used on the first
   day, the other on the 2nd day).

 - apparently, during your visit last september, you marked a different
   location as "Chajnantor South".  unfortunate, but, hell, these things
   happen at 5000 m!  this is the place where the pictures were apparently
   taken.  i gather that villanueva measured this location in october to
   be 627748 E, 7453112 N (you probably got the location from the ALMA
   memo - they're pretty similar).  this is *not* the correct "Chajnantor
   South" location.

we will have to fix the marker when we are down next week - to make sure
that the proper place is well marked (move the orange cone to the right
place), i guess...

	-bryan