Proposal Eligibility
To be eligible for VLA dynamic scheduling, you must have a regular
VLA proposal which was submitted at the deadline for the current
configuration, or approved for triggering on a known transient during
the current configuration, or pre-approved at an earlier deadline for
the current configuration. Alternatively, you must have an
exploratory or target-of-opportunity proposal that was approved for
the current VLA configuration. A VLBA proposal that requests a small
amount of prepatory VLA time may also be eligible for VLA dynamic
scheduling.
A valid regular VLA proposal will have one of the following
statues assigned by the VLA/VLBA Proposal Selection Committee, and
listed in decreasing order of the relative probability of actually
being scheduled:
- Target of opportunity, waiting for occurence.
- Approved for ToO triggering, this trimester only.
- Approved for dynamic scheduling, priority A
- Approved for dynamic scheduling, priority B
- Approved for dynamic scheduling, priority C
- Approved for dynamic scheduling, priority D
- Dynamic scheduling, lowest priority. Unlikely to accomplish goals.
- Time scheduled this config; will not be considered further.
- Time allocated for this configuration and subsequent one(s)
An approved VLA exploratory proposal will usually have a relative
priority below that of any regular VLA proposal.
Tactical Considerations
Consult the relevant VLA schedule
to see when the most available dynamic time occurs in the current
month. If your dynamic priority is low (e.g., C or D) and it is
possible to fit your observations into those most-available LSTs, you
should construct scheduling blocks to let this happen. If you cannot
use time at those most-available LSTs, then make your scheduling
blocks as short as possible, in hopes that you can fit into slots
unusable by the higher priority proposals.
If your proposal has a target of opportunity status or a dynamic
priority of A, you are likely to be dynamically scheduled soon after
your observe file has been queued. If your dynamic priority is B, you
are also likely to be dynamically scheduded but there may be a longer
delay after your observe file has been queued.
The shorter an observe file, the more likely it is that it can be
fit into the available dynamic time. But a short observe file is
often inefficient because of calibration considerations. Care should
be taken that the array has time to slew to the first source in the
observe file, which can consume a large fraction of a half-hour
observe file. Since you do not know where the array will be pointed
when your observe file starts to execute, it is probably a bad idea to
start your file with an important calibrator, which might get missed
due to a long slew.
If your science goals can survive poor phase behavior, it could be
to your advantage to specify that, as it may well open dynamic times
to you that would otherwise not be available.
If your science goals can be met during reconfigurations, it could
be to your advantage to specify that possibility in your observe file.
There is much more available dynamic time during reconfigurations than
during standard configurations. In deciding whether you can use
reconfiguration time, think of the array as already being in the
destination standard configuration, but with several newly-moved
antennas unavailable because their baselines, pointing, etc., are not
yet well determined.
Observe files for make-up observations due to hardware failure,
software failure and/or poor weather will be queued at priority
A.
