Minutes: Northern Multibeam Working Group meeting, Fri 8th June 2001

Those present: Peter J. Boyce, Marco Grossi, Virginia A. Kilborn, Robert Hugh Lang, Robert F. Minchin

Apologies: Michael J. Disney, Christine Jordan

Item 1. Computing / Software

It was reported that the latest version of gridzilla does not work correctly either at Jodrell Bank or Cardiff. VAK reported that this version does work correctly in Australia but extra fixes had to be applied to the version released with aips++ before it would work correctly. VAK is to liaise with Ant Holloway and Mark Callabretta in getting gridzilla working at Jodrell and then report on method to Cardiff.

It was reported by RFM that the previous version of livedata at Cardiff has ceased to work following the installation of the new version. The old gridder still works but won't work with the new version of livedata. RFM agreed to ask Rodney Smith to try to fix the older livedata so that we at least have a way of processing MB data in the UK.

PJB pointed out that we need to run the M81 Group data through gridzilla with the HVC option, in order to study the compactness or otherwise of objects close to 0km/s. We can produce mscal files using the new version of livedata in Cardiff. VAK undertook to determine if we could copy these to Aus and grid them using the new, working gridder over there.

RFM reported that a new 500GB hard disk has just been installed in Cardiff and requests for space on it can be made. The meeting resolved that we should ask for 80 GB. This would give us space to reduce the drift scan data (about 26 GB of mbfs) and also maintain all of the HIPASS/HIJASS cubes on disk. RFM is to request this space from Rodney Smith

Item 2. Hardware

RHL and VAK voiced concern at the pace of moves to solve the Athlon RFI problem at Jodrell. In particular, no progress seems to have been made in making a prototype RFI-"cage". Given that a large number of these need to be made, fitted and tested before our next observing run, this is a matter of great concern. It was suggested that we could borrow an RFI-cage from Parkes and that RHL could go to Jodrell to test its effectiveness. It was also reported by VAK that she has not been invited to sit on the committee which is responsible for sorting out the FRI problem. It was resolved that VAK should seek to be included on this committee.

It was resolved that a set of narrow-band (8 MHz) filters should be constructed to enable us to quickly confirm/reject low S/N detections found in HIJASS/drift scan data. RHL said he was filling to construct these filters if permission could be obtained from Cardiff for him to spend time at Jodrell Bank constructing them.

RHL also expressed the view that he needs to dynamically check some of the cables in the MB top-end. RHL is also concerned that there is no spare power-supply capacity at JB.

PJB resolved to contact MJD to express the view that there was a strong need for RHL to spend time at JB this summer

Item 3. Science

It was agreed that a study of the M81 Group as seen by HIJASS would form a suitable first publication from the group. PJB undertook to carry on working on this, subject to being able to obtain versions of the relevant cubes produced with the HVC option on livedata (see Item 1). It was resolved that an ApJ Letter should be our preferred place of publication. VAK resolved to find out if Jodrell would cover the page charges.

It was also agreed that a major catalogue paper should follow as soon as possible. VAK and RFM agreed to test out their automatic galaxy finders on HIJASS data. RFM undertook to test out the "matched filter" technique advocated by Jon Davies for finding galaxies in HIPASS data.

Item 4. AOB

None was raised.