At last the miserable weather of 2000 looks to have changed for the better, and just recently we have seen the best spell of dry weather since El Niño
From the Director's Desk
Ian Robson - Director JCMT
At last the miserable weather of 2000
looks to have changed for the better, and just recently we have seen the
best spell of dry weather since El Niño. Hopefully this bodes well
for 2001. Since the last Newsletter the main news to report is the cancellation
of the `black' time in semester 01A imposed by the 12-hour shifts due to
staff shortages. This is excellent news indeed and is a great testimony
to the enthusiasm of the TSSs to maintain the facility at full capability
(see below).
In November, in the light of a further TSS departure, the JCMT Advisory
Panel and Board considered urgent proposals to implement a rapid-action
project that would provide a remote, close-up facility for the telescope.
This would allow the JCMT to be staffed by a TSS at the summit for all
of first shift and some of second shift, the telescope would then be left
running while the TSS and observer drove down to HP, where the observer
would take over operations. Close-up would take place when the day-crew
arrived, or earlier if the weather deteriorated. There would be a number
of safety overrides so that in the event of inclement weather, the dome
would automatically close. Once the dome was closed it would not be able
to be opened again from HP. This project was only possible due to some
recent upgrades and the upcoming project to replace the telescope and carousel
control consoles. In the first instance this remote close-up would only
work with SCUBA, leaving non-SCUBA nights reduced to 12-hours for some
fraction of the time. The Panel and Board approved this project in an effort
to reduce the `black' time while not increasing staffing.
However, on discussion with the TSSs, Remo Tilanus found there was support
to change the shift pattern so that 16-hour nights could be retained. After
much intensive work, an agreed solution was found. This has been implemented
from early February and will last for the entire semester with a review
at the end of May. The Board was supportive of this action. Therefore,
observers should now have full 16-hour nights for the entire semester,
and should this experiment prove successful, this mode is expected to continue.
I cannot speak too highly of the professionalism of the TSSs in working
to reach this very satisfactory conclusion.
The only downside to the new pattern is that it removes TSS support
from the daytime. This has caused some reorganisation of ETS functions
and puts a restriction on extended observing, while not removing it altogether
in times of excellent weather. The remote close-up project has not been
abandoned, however; it has merely been slowed to a more reasonable pace
because this will also allow extended observing to be retained. This is
crucial so that we can maximise the observing time during excellent, and
in particular, El Niño weather.
Over the last six months the time lost due to faults has improved, which
is very welcome in itself. The Associate Director (Per Friberg) has been
charged with working with the Chief Engineer and Head of Software to identify
and come up with a plan to eliminate many of the niggling faults and to
reduce substantially the overall fault-rate. In this light the instruments
have been performing reasonably well; RxW suffered a rare failure of the
D-band multiplier, while SCUBA went through a period of noisy pixels and
dilution fridge problems that were eventually cured by a full warm-up and
bake-out. Experience now strongly suggests that this needs to be undertaken
about every four months and so in future this one-week downtime will be
hard-wired into the schedule. Unfortunately, due to a number of unrelated
reasons, the new holography receiver has still not been fully commissioned
but as this is being written we should be very close. This will then allow
us to move on to the next phase of the surface upgrade project.
Returning to SCUBA, while it continues to produce excellent and world-beating
science, those users who want the photometric pixels or the 750/350 channels
continue to be disappointed by their unavailability. This was discussed
at the ITAC and based on the scientific priorities, time out of service
and risk of the fix, the ITAC decided to continue to operate in the 850/450
mode for the coming semester. However, it was agreed that SCUBA should
be taken out of service for an extended period in summer 2002 for a thorough
overhaul, which will include the return of all filter modes. Observers
are hereby given advanced notice of this planned downtime. We are also
investigating whether we can obtain a further increase in sensitivity through
new feedhorns, which have just become available through a new machining
technique. If this proves feasible, then these will also be installed next
summer.
I again encourage RxW applications, the dearth of which continues to
baffle me given the high demand to build this excellent receiver in the
first place. I am working with the ITAC to explore ways to ensure that
users who obtain RxW time do get good weather.
The past few months have been very busy ones as far as the new instruments
are concerned. HARP had an excellent review meeting at MRAO in late November
and is on good track. This was followed by an equally successful Critical
Design Review of ACSIS at Penticton in December. It looks as though ACSIS
will suffer some further slippage, but will be at the JAC well in time
for HARP. For both of these projects, the software interface with the JAC
has become a priority and this will be addressed at an extensive meeting
in Hilo in early April. SCUBA-2 has just seen the project kick-off-meeting
at NIST in February. This went extremely well and it was very encouraging
to see how positively the two detector development teams were working together.
This project is currently going through the funding cycle in the UK and
will be the focus of the JCMT Board in May. The situation for CHAMP-D on
the other hand, does not look at all promising as Bonn has not been able
to appoint a project manager and so the required design review scheduled
for March is unlikely to take place.
Ian Robson - Director JCMT
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