Re: [alma-sw-ssr] Offline and Pipeline Requirements

[Frederic Gueth <gueth@iram.fr>]

mel wright 456 wrote:
> 
> Tim,
> 
>         It's good to have your participation, and know what
> to expect.
> 
> If there is a significant increase in image fidelity by
> going back to the uv-data in the deconvolution of mosaiced
> images, then this has a very significant effect on the operational
> model for ALMA image analysis.
> 
> It remains to be demonstrated that there is a meaningful
> increase in image fidelity with telescopes with real pointing
> and other errors, and what the cost in performance is.
> 
> These tests should be done as soon as possible, and I would be happy
> to provide some data. The attached MIRIAD script, takes
> about 5 min to make images, 10 min for SDI and 20 min for Maxen
> on a sun ultra 10 (93000 uv-points and 19 pointings and 64 channels).
>  The numbers can be scaled appropriately for ALMA.
> 
>                 cheers,
> 
>                         Melvyn
>  


In order to study the impact of the ACA on the imaging
capabilities of ALMA, there has been a considerable effort
this summer to get simulations of the whole imaging process 
as realistic as possible.

At IRAM, we have developed a simulator in GILDAS. It 
includes pointing errors, anomalous refraction and phase 
errors induced by an atmospheric phase screen, amplitude 
errors, etc. Mosaicing is the default mode. The deconvolution 
is done with CLEAN or one of its variant. You can check the
(preliminary) results at: http://iram.fr/~alma

Frederic.