Westerbork report to TOG, Oct 2000

Hardware

During 2001 Westerbork will need some VLBI tests outside the sessions to confirm that TADUmin works

Online Software

TMS

Since Session 2 we have been operating continuously under TMS (Telescope Management System) software. There are still bugs being removed, but work is continuing to improve its reliability and flexibility. In particular a new VEX parsing system is being made for future tied-array observations.

One unfortunate byproduct of the current TMS implementation is that, for the tied array, the minimum gap between scans (even of the same source) has increased to 130 seconds. Work is in progress to reduce this dead-time. To allow for phase-referencing observations we have implemented a quasi-mosaic mode, i.e. the source and reference(s) are treated as an oddly shaped mosaic and are done as one scan. Users should beware that this involves human intervention at present, so they must deliver schedules on time. We plan to keep local synthesis observations on disk locally in Westerbork at least 2 weeks after measurement; people who want the local synthesis taken during tied-array operations should request these before this.

FS

The DOS software, which switched the phasecal injection in our reference single-dish (RT7), has been ported to the FS. This now allows us to switch the phasecal on and off from FS procedure files and minimize possible operational errors by leaving it on during local observations.

It would be convenient if DRUDG made schedules switch off the phasecal when they end

The field system version we use is currently 9.4.13.

Offline Software

Other

• WB has ordered thin tapes.
• Several spare parts have been purchased, in line with the list on the evntech list.
• We plan to buy a MkIV decoder.
• There is a much improved Westerbork web page at http://www.nfra.nl/wsrt. Many thanks to Rafaella Morganti. A recent summary of the VLBI status will be kept under http://www.nfra.nl/wsrt/WSRTmodes/WSRTmodes.html.