[mmaimcal]Meeting

[Angel Otarola]

Hi Mark,
Another idea:
4 moves/day, 3 times per week (Monday, Thursday, Saturday for example)
Also assuming 6 weeks for compact and y+ configurations per cycle, we then 
get to the following situation:

Compact (N-S sub-configuration included)         6 weeks
March OUT                                       12 weeks
Y+ Configuration                                  6 weeks
March IN                                         12 weeks
------------
Total: 36 weeks (9 months).

So in principle you will shift 1 season (quarter of the year) per year. In 
this case Compact and Y+ configurations will shift to the opposite seasons 
every two years. Sound this right?

Cheers,
Angel







At 03:13 PM 12/10/2002 -0700, Mark Holdaway wrote:


>Folks,
>
>With 4 moves per day made 2 days per week, it takes about 18 weeks to go
>from COMPACT to Y+.  Making an assumption about how long you sit in the Y+
>and COMPACT arrays (15% in COMPACT, 15% in Y+),
>
>we end up with something like:
>
>         7.5 weeks       COMPACT (including N-S extension)
>         18 weeks        march OUT
>         7.5 weeks       Y+ config
>         18 weeks        march IN
>---------------------
>         51 weeks
>
>
>Which, at first thought, is great (ie, drink vodka for a week and we've
>got 52 weeks even), but on second thought, is BAD.
>
>We want the arrays to cycle through the time of year.  When we MARCH
>through the intermediate arrays, we'll hit them in SPRING and FALL, or
>in WINTER and SUMMER.  It isn't quite that simple because small
>intermediate arrays will aloways be close to the compact array and will
>not be 6 months apart.  BUT, we'd like to cycle through the seasons
>in a different way, so that EVERY configuration gets to see EVERY
>source with good TAU and PHASE STABILITY sooner or later.
>
>
>Questions:  1) What about the assumptions of 15% of the time in Y+ and in
>         Compact?  If these go down to 5%, the whole cycle is like 40
>         weeks, so we cycle through the seasons roughly every 3 years.
>         I DISAGREE WITH THIS ONE.
>
>         2) If we sit in Y+, Compact for LONGER, ie, 22% each, we get
>         something like a 1.25 year configuration cycle, which will
>         cycle through in 5 years (similar to VLA, which is 4 years).
>         I AM GUESSING THIS IS TOO LONG, BUT COULD BE RIGHT.
>
>         3) Other options include moving antennas 3 days a week or
>            3 days every 2 weeks to speed up or slow down the cycling;
>         WHAT DO YOU GUYS THINK?
>
>         4) Or do like the VLA and MARCH the antennas one way as fast
>            as you can, skipping stations, to get from say COMPACT to Y+
>            FAST, and going liesurely the other way.
>            But I believe this goes against the ideas we've gone
>            along with in the past:  smooth reconfigurability.
>         I AM AGAINST THIS IDEA, BUT FOR NO GREAT REASONS.
>
>Ultimately, observing pressure (perhaps with administrative nudges) will
>decide exactly what happens here, but it would be good to find a scheme
>that both matches observing pressure and fits nicely with our desire
>for cycling around the seasons (ie, is consistently either a fair bit
>SHORTER or LONGER than 1 year even).
>
>
>I'M JUST LOOKING FOR OPINIONS RIGHT NOW.
>
>
>Take care,
>
>     -Mark
>
>
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