From: <Tasso.Tzioumis_at_email.protected>
Date: Thu, 1 Sep 2005 01:37:17 +1000

Hi Steven and everyone,

Terrific job done beautifully. We will get there in the end.

Can I suggest that next NZ test involves at least 2 Oz antennas to
check out that the system is working and home in any problems?

Cheers
Tasso

On 31/08/2005, at 2:55 PM, Steven Tingay wrote:

>Jim,
>
>
>>I'm a bit surprised that the non-detection from the 6m to Australia
>>is due to sensitivity. Even in 1 second, a 5 Jy source should be
>>detectable from a big Australian antenna to the 6m. All else being
>>equal, the sensitivity of the 14m-ATCA baseline should be better than
>>the 6m-ATCA baseline by the ratio of the product of the antenna
>>diameters. So if 1-sigma on the 14m-ATCA baseline is 0.35 Jy, 1-sigma
>>on the 6m-ATCA baseline should be 0.35 * (14/6) = 0.8 Jy. So 0537-441
>>should be a 6 sigma detection to NZ in 1 second.
>>
>
>Yes, this matches my rough calculation of what we should have
>expected...
>
>....If everything was working ok with the equipment, which I am not
>sure
>it was. Pointing is a possible worry too, and timestamping of the
>data
>was an even bigger worry at the time, as was the maser etc etc. We
>found
>and eliminated a number of noise sources in the 6m environment that
>substantially raised the Tsys. Also, we really have no idea how
>well the
>feed sat at the focus of the 6m and how the surface (and surrounding
>ground!) was illuminated by the feed. The sensitivity may well
>have been
>compromised by a raised Tsys.
>
>In short there are a number of unknowns with the 6m, which was
>exactly the
>reason we did tests in a controlled environment in Hobart.
>
>We now have a VLBI result and better confidence if we do a further
>test
>with the 6m.
>
>Cheers, Steven
>
Received on 2005-09-01 01:37:43