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Item 3.4
ATNF ATUC Memor andum To: From: Date: Subject A TUC Jim Lovell 2006 June 1 Tidbinbilla report

1. 70m Observi ng stati stics for January to June 2006. Currently there are 9 active proposals and observ ations have been completed for 2 of these. Three propos als are for zero-spacing maps to support ATCA observ ations and t wo propos als are for pulsar obs ervations. A s tatus summary of propos als is available on the ATNF web pages and is regularly updated. Bet ween July and December 2005 no observations were made wit h the 70 m antenna due to maintenance activities and no obs ervations have been possible since (see item 2). 2. 70m Antenna Mai ntenance. From July 18 until January 2006, the 70m underwent maintenanc e on the azimuth bearing and the antenna controller hardware was upgraded. Sinc e coming back from maint enance the 70m has had servo problems that have prevented us from pointing the ant enna acc urat ely enough in the 12-mm band. The sy mptoms of this problem are long settling times and the antenna wandering on and off point but up to half the beamwidt h! Until this problem is fixed it is not pos sible to schedule any observ ations. Howev er, in the meantime, the available time has been us ed to develop on-the-fly mapping. 3. Development. The most limit ed resource at Tidbinbilla is observ ing time, grant ed to us by NASA. Therefore dev elopment work is aimed at getting the most scienc e out of the available time by improving observing efficiency. In the past , this work has included increasing the instantaneously accessible bandwidth to allow more spectral lines to be observ ed simultaneously and improving the observing software to reduce ov erheads. There are two main development tasks currently underway. The first is an implementation of on-the-fly (OTF) mapping, as request ed by ATUC. This will improve the efficiency of mapping and antenna pointing meas urements over the current point-by -point met hod. The sec ond is an upgrade to the 12mm system on the 70m from one to two channels. The upgrade will allow dual polaris ation obs ervations, improving sensitivity by a fact or of 2 and halving the integration time required to reac h a giv en sensitivity limit. · OTF Mappi ng. New obs erving soft ware is under development to implement OTF mapping. To test this, observ ations at 13 c m have been made to map the beam and results appear promising. More software work is required but the res ults to date indic ate that OTF mapping should be possible. 12mm dual polarisati on upgrade. Installation of the s econd down-conv ersion chain has been progressing slowly, primarily bec ause efforts hav e been concentrated on testing the servos and OTF mapping development. We hope to start testing the sec ond channel in the next few months.

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4. 34m beam-waveguide antenna DSS34. At the last meeting, ATUC made the following rec ommendation:


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ATUC reco mmend that DSS-34 time is made availab le at the next Announcemen t of Opportun ity and tha t the ATNF suppo rt observations on a best-e ffo rts bas is with current resources. The Director responded: At as to sc time of writing tronomy . Un til begin offering hedule. This is (Ma rc they d DSS -3 likely h 2 0 0 6 ) NASA o it see ms pre 4 once radio a to be the 2007 have no t ye t s tarted to a llocate DSS-34 time fo r radio matu re to be o ffe rin g this facility. Therefo re we p ropose s trono my allocatio ns begin appearing in the NASA Ap ril semeste r

DSS-34 radio astronomy allocations have now started to appear in the schedule wit h time bec oming av ailable from lat e June. This will be used for some test observations and if all goes well, DSS43 will be offered for the 2007 April semester.