Memorandum to VLA/VLBA Proposers and Observers

News

General announcements and news for investigators proposing to use the VLA, VLBA, HSA, and other VLBI facilities for the 2009 October 1 deadline will be available in mid-September. Some basic information concerning the October 1 proposal deadline is already available.

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 2009-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 DnC, D, or subsequent configurations has been previously allocated.

VLA Scheduling

This takes two forms, fixed date and dynamic. Some approved proposals will be scheduled on fixed dates; time for them was allocated for the DnC configuration (September 25 to October 12), for the D configuration (October 16 to January 11), or for the associated reconfigurations (September 14-25, October 12-16). 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 DnC or D configurations. 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.

VLA Statistics

The oversubscription rate for the D configuration was about 2.3 after subtracting time allocated to maintenance and software development, and subtracting time previously allocated as part of a multiconfiguration proposal. The oversubscription was heavily concentrated at 12h LST, with a secondary peak at 18h. There were 93 active VLA proposals. We allocated time for 31 VLA proposals, accepted eight as target of opportunity proposals waiting for an event of known type, approved 26 for insertion into the VLA dynamic queue, and rejected 27 proposals. The average time per approved proposal was 29 hours for the VLA (23 hours excluding four Large proposals). Information from the VLA/VLBA Scheduling Officers includes a table of approved VLA/VLBA proposals.

VLBA Scheduling

This 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.

VLBA Statistics

There were 1292 hours requested for the High Sensitivity Array (HSA). There were 9802 hours requested for the VLBA, 6721 hours at 256 Mbits/sec or lower (the standard recording rate), 3081 hours at 512 Mbits/sec (the current maximum rate). For comparison, in a recent trimester, the VLBA observed 1350 hours. There were 45 active VLBA proposals and four new Global Network proposals. We approved five VLBA proposals for fixed time scheduling, four for the HSA. We approved 16 VLBA proposals for the dynamic queue, four at high priority, 11 at second priority, one at low priority. We rejected 19 VLBA proposals. The average time per approved proposal was 68 hours for the VLBA (32 hours excluding four Large proposals). Information from the VLA/VLBA Scheduling Officers includes a table of approved VLA/VLBA proposals.

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.

Copyright © 2009 Associated Universities, Inc.
The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Modified on Tuesday, 01-Sep-2009 09:10:02 MDT