[mmaimcal]Y+ Simulations

[Mark Holdaway]

I see three different sets of Y+ imaging simulations to do:

1. Full Resolution Simulations

The main drawback of the Y+ configurations, which NOBODY
seems to be picking up on, is it's probable inferior
snapshot imaging.  I aim to investigate this in the full
resolution array by looking at the imaging performance
over 30 minute, 1 hour, 2 hour, 4 hour, and 8 hour integrations.
I anticipate that the ring array's image quality will not 
change greatly with increasing integration time, while the
Y+ configuration will.

In addition, I'll add noise of varying amounts (just seems like
the right thing to do) so I'll have, for a given configuration,
a simulation result matrix that looks like:

                 integration
noise     0.5    1.0    2.0     4.0   8.0
 0.1
 0.5
 2.5
 12

We'll have one such matrix for each of the array configurations
in:  ring, loose Y+, tight Y+, strict Y.

This will take some time in doing the computing.




2. Sensitivity Loss with Resolution

No actual imaging needs to be done here, just simulation
and reweighting to achieve the desired resolution.

We DO need to have a guess at the distribution of desired
resolutions.  I would guess for a first pass that we want
a large fraction of the Y+ observations at the full resolution
(50% ?), and the rest are logrythmically distributed between
the full resolution and the largest spiral configuration.

This will not take much time (which is why I've listed it 
second priority and not third).



3. Imaging quality of the incremental Y+ configurations

The incremental Y+ configurations will have generally superior
imaging performance as compared with the ring array tapered to
the proper resolution for comparison.  (The ring array will
participate in observations in which the longest baselines
resolve out the detectable structure, so tapering will happen.)
We could quantify this.  Rather than perform an exhaustive
comparison, I suggest that we take two of the incremental 
configurations and compare them to the taperd ring array,
but just for some simple cases.

We could pass on this if we run out of time.





	   -Mark