Data Access

by Stephan W. Witz last modified Apr 11, 2012

The online archive contains all VLA data since observing started in 1976, and will also serve the user community with EVLA data. The entire archive is now on disk, and is available via the Archive Access Tool at http://science.nrao.edu/facilities/evla/archive/evla/. This interface provides a basic data retrieval tool if you know the program code of your observations. It also provides an advanced query tool which enables searches based on a large number of user-specified criteria. Data can be downloaded via standard ftp protocols. With the exception of some rapid response and large proposals, (E)VLA data associated with a given proposal normally are restricted to proprietary use by the proposing team for a period of 12 months from the date of the last observation in a proposal (Note: data taken more than 12 months previously may still be proprietary, if additional data for the same proposal have been taken within the last 12 months). Proprietary data may be downloaded by the observing team by making use of the project key (see The Observations and Remote Observing).

Data are stored in the archive in the Science Data Model (SDM) format that will be used by both the EVLA and ALMA. They are available through the Archive Access Tool in one of two formats:

- As a CASA Measurement Set.
- In UVFITS format, which can be read by either AIPS or CASA.

The raw SDM format will only be available by special request.