[alma-config] Imaging simulations for ACA

[Kouichirou MORITA]

Hi Melvyn,

Thank you for your comments.

> I like your conclusion that 6 m 
> antennas would provide better performance on wide field imagings 
> than with 8 m antennas. !
>
> some comments and questions.
>
> 1. You show several configurations of 6m antennas - 
> which configuration appears to be best ?

Among configurations used these simulations, 18 x 6 m ACA 
showed the best performance.  But I have an indication
that imaging performance of ALMA+ACA depends on sidelobe
level of ACA.  The shape of these configurations is too 
regular, so some randomizations to reduce the 
sidelobe level are needed, I think.


> 2. " smoothed 
> total power data instead of raw total power data from 12 m 
> antennas. Improvements of imaging quality have been obtained 
> by this method." 
> -- so do you efffectively use only up to ~ 6m spacings from the
> 12m antennas ?

Yes.  But, I should test different beam width for the smoothing.

> 3.  In calibrating the compact array, I think it's reasonable to use
> nearby 12m antennas as part of a calibration.

I agree with you.

Regards,
Koh-Ichiro