Memorandum to VLA/VLBA Proposers and Observers

News

News for Proposers

General announcements and news for investigators proposing to use the VLA, VLBA, HSA, and other VLBI facilities for the 2008 October 1 deadline will be available in mid-September.

Fermi Collaborative Observing

Through an agreement with the Fermi Gamma-ray Space Telescope, up to 10% of the total observing time on each NRAO telescope was made available for collaborative observing. Fermi launched on 2008 June 11 and Cycle 1 observing began on 2008 August 14. During Cycle 1, approximately 300 hours of collaborative observing will occur on the VLBA, with less time occuring on the VLA and the GBT. Abstracts of successful Cycle 1 proposals are available.

Prompt ToO Overrides for VLA Proposal AO229

We will continue a scheme wherein this proposal team is authorized to conduct prompt target-of-opportunity (ToO) overrides in response to stellar superflares. Proposal AO229 expires at the end of trimester 2008-T3. Time taken for such overrides will be rescheduled on a best-effort basis. To minimize the impact of overrides during sessions longer than a few hours, we remind observers that it is always prudent to include more than one observation of a primary flux density calibrator and, if appropriate, a bandpass calibrator.

Current Regular and Large Proposals

General

Information about the status of all current proposals on which your name appears has been e-mailed to you, in a format described under Static Information below. That e-mailing (a) includes proposals just considered for trimester 2008-T3 plus those waiting for future trimesters, whatever their date of submission; and (b) does not include proposals submitted earlier that are waiting in the dynamic scheduling queues or multi-configuration VLA proposals for which time in the A or subsequent configurations has been previously allocated.

VLA

Scheduling takes two forms, fixed date and dynamic. Some approved proposals will be scheduled on fixed dates; time for them was allocated for the A configuration (October 3 to January 12) or for the associated reconfiguration (September 15 to October 3). Some approved proposals have been accepted for insertion into the VLA dynamic scheduling queue; a Guide to VLA Dynamic Scheduling is available, including descriptions of new dynamic parameters related to monitoring or survey observations. Proposals requesting future configurations in some cases have been allocated time in those configurations, and in other cases have been retained for future consideration. We rejected proposals which we were unable to schedule or unwilling to queue, and which required only the A configuration. We also, in most cases, rejected unscheduled proposals which were submitted more than one year ago, or for which it is clear, due to referee ratings or other reasons, that the proposal will not be accepted within one year from its submission date.

VLBA

Scheduling takes two forms, dynamic and fixed date. Most approved proposals have been accepted for insertion into the VLBA dynamic scheduling queue; a Guide to VLBA Dynamic Scheduling is available. Rare proposals, particularly those requiring other resources such as a non-VLBA antenna, will be scheduled on fixed dates with notification to the observers about six weeks in advance.

Statistics

The oversubscription rate for the A configuration was about 1.3, after subtracting time allocated to maintenance and software development, and subtracting time previously allocated as part of a multiconfiguration proposal. There were 216 hours requested for the High Sensitivity Array (HSA). There were 1738 hours requested for VLBA observations (753 hours at 128 Mbits/sec, the current sustainable rate; 585 hours at 256 Mbits/sec; 399 hours at 512 Mbits/sec). For comparison, in a recent trimester the VLBA observed for 1304 hours, of which 288 hours were allocated through the prior large proposal process. There were 131 active VLA proposals, 51 active VLBA proposals and five new Global Network proposals. We allocated time for 57 VLA proposals, accepted five as target of opportunity proposals waiting for an event of known type, approved 21 for insertion into the VLA dynamic queue, and rejected 47 proposals. One of the VLA proposals entered into the dynamic queue, AR685, is a newly-accepted large proposal. We approved four VLBA proposals for fixed date scheduling, one for the HSA. We approved 16 VLBA proposals for the dynamic queue, seven at high priority, six at second priority, and three at low priority. We rejected 28 VLBA proposals. The average time allocated per regular proposal was 14 hours for the VLA and 24 hours for the VLBA. Information from the VLA/VLBA Scheduling Officers includes a table of approved VLA/VLBA proposals.

Future Regular and Large Proposals

Details for the next two proposal deadlines are available.

Related Postings

These include the NRAO Proposal Referees' Guide, a complete description of the VLA/VLBA Time Allocation Process, and the proposal process for Rapid Response Science.

Static Information

Proposal Summary

The first line contains the proposal code and title. The second line informs you if we have scheduled time for the proposal, and whether it will be considered for more time in the future. If you expected the proposal to be considered for a future trimester, and this is not indicated in this line, please let us know by the next proposal deadline. This line is followed by comments from the VLA/VLBA Proposal Selection Committee, or from other considerations of the proposal, and then the list of authors of the proposal. For proposals for which we have allocated VLA or VLBA time, a list of the times tentatively allocated, with configuration, and a breakdown in terms of sessions with approximate centering in VLA sidereal time is given. We also list the times requested, with a similar breakdown, and times previously scheduled.

The reports from the referees follow and they contain a numerical rating. The referees use any numerical system with which they are comfortable, subject only to the convention that the smaller the rating, the better the proposal. We include the median of the ratings given us by that particular referee in order to judge the relative rating of your proposal. The referee ratings are strongly advisory to the Committee, which, however, may also apply considerations of similar archival observations, logistics, resources used, etc., to decide which proposals to schedule.

For most proposals that supplied a source list we have searched the VLA or VLBA archive for previous observations of the same sources, except for the Galactic Center and Orion A in which the listings would be too voluminous to be very informative. We include this listing in the e-mailing sent to the lead proposer only. These listings give the name, position, type of observation (blank indicates continuum, codes starting with a number are line modes, VLBA observations show recording mode), frequency of observation, bandwidth, time on source in minutes, number of antennas, proposal code, observer's name, configuration and date. Observations are selected on the basis of positional agreement only. We include this information since it may be of value to the proposer, as it often was to the Committee in evaluating the proposal.

VLBI Global Network Proposals

NRAO evaluates these but the final choice of proposals for scheduling, for either the centimeter or the 3mm sessions, is done by negotiation between the US and European schedulers.

Modifications

Unless stated otherwise, any time allocated is only for the proposal given, and no substantial modification in the program should be made without consulting with schedsoc@nrao.edu (and R. Porcas for VLBI Global Network proposals) before doing so.

Public Outreach

The NRAO can help observers and their home institution prepare joint press releases, and/or help prepare enhanced graphics for publications. The NRAO encourages observers to submit images from their research to its on-line image gallery. Contact: mtadams@nrao.edu.

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Modified on Wednesday, 27-Aug-2008 12:29:00 MDT