[mmaimcal]Re: SMA Calendar 11/16/03

[Al Wootten]

Dear Jim, and Mark

Congratulations on reaching this tremendous milestone!  I look forward 
to reams of great scientific results from SMA over the more than eight 
years it will take ALMA to go from groundbreaking week before last to 
reach its comparable milestone.

Clear skies,
Al

James Moran   wrote: 
                        +
> +   The first image has been made with the SMA with data from all 28          +
> +   baselines among 8 antennas. It is a continuum image of Mars at 1.3 mm.    +
> 
> Mark Gurwell made the first SMA image with eight antennas and 28 baselines
> operational on NOV 14. The image was made in the continuum at 1.3 mm of Mars
> with only nine minutes of data on source (see Test Log Entries 6243 and 6253).
> This result was made possible by a successful set of baseline determination
> observations on the previous night (see Test Log Entry 6231). In turn, a full
> baseline solution was made possible because the phase jump problem in baselines
> linked to Antenna 8 has been solved. The problem was software related; its
> exact cause has not been determined. However, Taco discovered that the phase
> jumps disappeared after he modified the DDS software to write the data
> for Antenna 8 into the hardware registers twice (see Test Log Entry 6220).
> Gurwell found the "smoking gun," a stretch of data showing the fringes
> in a baseline linked to Antenna 8 going into rapid rotation, which was
> traced to a failure in the primary DDS phase rotator (see Test Log Entries
> 6215 and 6214).

 >
 > The current phase of the correlator expansion is DONE! First fringes were
 > observed with all baselines (28) at full bandwidth (6 blocks or 2 GHz) on
 > Mars on NOV 13.