[alma-config] Pads for the largest array

[Min Yun]

Al,

If we include the 10+ km array, which requires yet another 60 or
so pads, the total number of pads would increase to about 250.
For the zoom spiral, that's more like 270, and perhaps even more pads
if the zoom spiral requires a separate "compact configuration".  
As I stated at the ASAC meeting, there is abundant
scientific reasons to have the 10+ km configuration, but it has
a significant cost in infrastructure (at least $6M) and time 
penalty for reconfiguration (10-14 days just one way).


					-- Min
					
p.s. The strawperson configuration I have in mind is a little
different from Leonia's earlier memos (which was also for only
40 antennas) so that each pad is used by two different configuration
(except the inner most cluster and the outer 3 km ring).


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> From: Al Wootten <awootten at cv3.cv.nrao.edu>
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> Min wrote:
> 'The numbers of pads needed for the current strawperson donut design
> is 192 (vs 180 in your case), so the difference is not large.  If
> you need further 30 pads for the 3 km ring, then the zoom spiral
> design actually requires 18 additional pads.  By the way, the 
> 192 pads needed for the donut configurations also include all of the
> pads needed for the compact configuration as well. '
> 
> Leonia--were the interesting array ideas you proposed in ALMA Memo No. 296
> constrained to share pads in any way?  The project budget is due soon
> at NSF and we'd like some idea of the number of pads to be used.
> The current 160 is clearly an underestimate.
> 
> Thanks,
> Al
> +--------------------------------------------------------+
> | Alwyn  Wootten   (http://www.cv.nrao.edu/~awootten/)	 |
> | Project Scientist, Atacama Large Millimeter Array/US   |
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