MERLIN Archive Data Access Policy

It is the policy of the MERLIN/VLBI National Facility that the investigators named on a MERLIN proposal have the sole right of access to the data obtained for that proposal for one year after the end of the Semester in which the observations were made. If the data are part of a programme with long-term status then the investigators have sole right of access to all the data of that programme for one year after the end of the Semester in which the final set of observations were made.

As of June 25, 2001, we will be making the MERLIN archive accessible via a web interface. The archive contains all raw data, currently stored on tape. In addition public domain continuum data is being converted to FITS format, calibrated and images produced. Thumbnail plots of images and visibility distributions will be placed on the web. The images will be preliminary, in that in many cases further editing, self-calibration or other refinements may be required to bring out particular features of interest.

A FITS file of a particular continuum image, or a copy of the calibrated visibilities for publically available continuum data can be obtained from the web-page. Spectral line data will not be available directly through the web page but the raw data will be available upon request from the MERLIN data archivist ( If you or your colleagues subsequently publish or use MERLIN data we request that you use this acknowledgement.

As we work through the archive (starting with L-band data taken in 1998) we will contact the PIs of a proposal two weeks before the data becomes visible on the archive. The PI will be offered an opportunity to argue for an extension of the one-year time limit. All requests for such extensions must be made to the Director of the National Facility (

June 2001