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VLA Configurations and Proposal Deadlines

The antennas in the Very Large Array are used like the zoom lens in a camera. When they are in the A configuration, the telescopes extend over the 21 kilometer (13 mile) length of each arm. This simulates a single dish that is 36 kilometers (22 miles) in diameter. In this configuration, we have the most magnification and can see the greatest detail. The size of the array gradually decreases with the B and C configurations until, in the D configuration, the telescopes are all placed within .6 kilometer (.4 mile) of the center. In the smaller configurations, scientists can study the overall structure of the source they are observing. By observing the same source in each configuration, scientists can gather a great deal more information.

The telescopes are moved about every four months. The configurations listed below with a lower-case "n", such as "DnC" and "BnA" are hybrid configurations in which the antennas on the east and west arms are moved in for the next configuration, but those on the north arm remain extended for a short time to enhance our view of sources in the southern sky near the galactic center.

VLA Configurations for 2007-2008
DATES CONFIGURATION PROPOSAL DEADLINE
19 Oct 2007 - 04 Feb 2008 B Jun 1, 2007
15 Feb 2008 - 03 Mar 2008 CnB Oct 1, 2007
07 Mar 2008 - 27 May 2008 C Oct 1, 2007
06 Jun 2008 - 23 Jun 2008 DnC Feb 1, 2008
27 Jun 2008 - 15 Sep 2008 D Feb 1, 2008
03 Oct 2008 - 12 Jan 2009 A Jun 2, 2008

VLA Configurations for 2007-2009
(dates are approximate!)
January-April May-August September-December
2007 D A B
2008 C D A
2009 ? ? ?

The prototype EVLA correlator is scheduled to arrive at the VLA summer 2008, coinciding with D configuration. There is no plan for correlator testing to impact the regular configuration cycles during 2008, but there may be some modifications needed in 2009 to accommodate EVLA commissioning. The schedule for 2009 will be updated as soon as these plans are finalized.

For more information on the VLA, see "An Overview of the VLA" in the Observational Status Summary.

Modified on Thursday, 10-Jan-2008 16:11:46 MST