I have received answers from Karl Menten, currently secretary of ASAC.
The ASAC very strongly recommends that dynamic scheduling
should be the default mode.
calibrated images are the final data products! This would
result in a much lower usage threshold for
non-radio-astronomers.
[2e]using calibrated uv data and maps of the project source(s)
in order to derive simple quality parameters (noise level,
signal to noise ratio): would be useful in certain cases, but without a source
model in general pretty difficult. [we were thinking of inserting short dedicated point
source observations for this]
[2f]using calibrated uv data and maps of the project
source(s) in order to derive similar or more sophisticated
parameters (source size, number of sources ... see examples
in memo 293) to be fed back into the project's observing
process, which may then take automatic decisions:
This should be left to the astronomer. To allow this and
at the same time not to slow down project completion too
much, a project could have predefined breakpoints, at which
the astronomer evaluates the data taken so far, and the
subsequent course of the project depends on the astronomer's
decision.
Such a feasibility, in addition or as an
alternative to breakpoints, should be given a low priority,
but it looks like it doesn't require more resources than (2e)
apart from a definitely more intelligent pipeline. We should
try not to let it be designed completely out of the system.
[3] Operator vs staff astronomer duties:
Allocation of antennas to simultaneous projects (e.g. a
sub-array for calibration, a sub-array used for astronomy,
some antennas in maintenance) ?
Operator, after consultation with local staff
astronomer.
Control on the dynamic scheduling process? Operator, but only in case of emergency.
Communication with the PIs if needed? Local staff astronomer.
Data proprietary period All the header information should be public immediately to
avoid duplication.
For the data, a proprietary period of 1 year seems
reasonable. This applies to the target source data. Phase and
flux calibrator data should be public immediately.
In certain cases, in particular for PhD projects, the
proprietary period might be extended.
For complex projects, such as surveys or projects
requiring many configurations, it might be appropriate to let
the proprietary period start after all of the data have been
collected.
[4.2] if public data is reprocessed in the pipeline by
others, to search for unforeseen scientific results, does this
start a new proprietary period ? [reply] We don't think that this would be appropriate - it would be
easy to block data forever by periodically re-processing them.
Special modes: Arnold Benz will organise a
discussion at the IAU General Assembly in Manchester (August
2000) on solar, stellar and possibly pulsar science
requirements for ALMA. He will in addition also contact some
other specialists in the field that will not be in
Manchester.
It would be better if one of us would attend that
discussion; Al Wootten plans to go to Manchester.
Status of Use Case writing
We have a draft of several high level use cases, which we plan
to finalize at a meeting in Grenoble two weeks from now. The output
will be discussed in the SSR, and will include a list of points that
need to be precised or are still missing in our requirement
document. One of the difficulties (I think) is that our requirements
do not translate all into top-level Use Cases, some are at a lower
level but are nevertheless important. We should also define more
precisely the observing modes, and their reduction procedures.
Specific issues which came out recently:
blanking:
Ideally we should have perfect hardware an not need blanking
at all. But in reality we could use blanking for bad LO lock and
high pointing errors. Blanked records will have a specific flag so
that they may or may not be used in further data reduction (for
high-dynamic range projects for which the closure relations have
to be conserved).
Should we have the real time option, when one antenna fails
part of the time, to blank either all baselines connected to that
antenna or all baselines (to keep closure relations) ?
Status of detailed requirement lists
We have draft lists on some areas: real-time control, pipeline,
archiving, GUIs This is an on-going process. drafted should be posted
on the list and discussed freely.
I think at this point I will draft a document including all
requirements and make sure they are consistent. My deadline would
be end of August.
Test projects ?
There was a low reply rate to Mel's call. It seems that the
amount of work implied at this stage is too high considering that
some hardware features (like the frequency plan) might still
evolve. We should keep this idea in mind for a later stage.
Next phone meeting: last week of August.
to be finalised by email in the next few days.
Face to face meeting in November ?
This could be either in San Francisco or in Socorrro or Tucson
(to same travel money). Could be just before of after the ADASS
meeting November 12-15, 2000 in Boston?
other issues
Virtual observatories (meeting attended by Steve Scott): The
main issue is that we have to ensure uniform data quality for the
archive.
Test point sources sources included for quality checking: they
could in principle be the phase calibrators themselves; but some
phase effects (e.g. the radiometric phase correction) might be
undetected if the antenna is not actually moved. However if the test
point sources are observed, then they can be used a
posteriori to improve the phase calibration.
