VLBI network design

1. Australian Government Geoscience Australia VLBI network design NGRS Workshop, 1-2 February, Canberra

2. Geoscience Australia 02 February 2006

3. Geoscience Australia 02 February 2006

4. Radiotelescopes in Australia Geoscience Australia 02 February 2006

5. Radiotelescopes in Australia Geoscience Australia 02 February 2006

6. New network benefit Geoscience Australia 02 February 2006

7. New dish/network design benefit • Model sXp sYp sUT1 sNut1 sNut2 chi-sq Number • (μas) (μas) (μsec) (μas) (μas) of scans • ____________________________________________________________________________ • 6 stations 118 98 4.1 233 82 2.024 3290 • 6 st + Hartrao 101 61 4.2 168 60 1.646 3179 • 6 st + Hobart 81 69 3.4 156 61 1.657 3442 • 6 st + Yarra 58 59 2.7 133 47 1.693 3739 • 6 st + Y&Hob 58 54 2.7 133 45 1.646 4181 • 6 st + Y&Hart 43 47 2.5 116 43 1.553 3542 Geoscience Australia 02 February 2006

8. Hobart, 26-meter antenna Too far from all other radiotelescopes; Limited amount of good radiosources in the southern hemisphere; Slow slew rate (1 deg/sec) – little data; Old design Geoscience Australia 02 February 2006

9. New radiotelescope design • Small size (< 20 meter); • High slew rate (> 5 deg/sec); • Near real-time VLBI; • New equipment (broad band receiver 1-32 GHz); • 5 deg elevation angle limit Geoscience Australia 02 February 2006

10. Scheduling • sharing time between astronomical VLBI and geodetic VLBI - 50/50 - IVS makes schedule on annual basis - ATNF makes schedule on semiannual basis - at least one Australian site each calendar day - own time assignment committee? Geoscience Australia 02 February 2006

11. TRF daily difference time series Geoscience Australia 02 February 2006

12. TRF daily difference time series Geoscience Australia 02 February 2006