Investigating a continental Australian VGOS VLBI intensive for UT1-UTC determination

Abstract In this simulation study, we investigate the potential performance of VLBI Intensives using the AuScope 12-metre VLBI network. This continental Australian network consisting of three stations, has recently been fully upgraded with VGOS receivers and has the capacity for observing the first southern hemisphere VGOS Intensive series. This Intensive series can be conducted entirely in-house, from the scheduling through to the correlation and post-processing. We determine such a VGOS Intensive series could achieve a median performance, with respect to the estimation of UT1-UTC, of $$9.74~\mu$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>9.74</mml:mn> <mml:mspace/> <mml:mi>μ</mml:mi> </mml:mrow> </mml:math> s for mean formal error and $$17.95~\mu$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>17.95</mml:mn> <mml:mspace/> <mml:mi>μ</mml:mi> </mml:mrow> </mml:math> s for repeatabiliy, which is comparable to existing inter-continental S/X Intensive series. Additionally, we investigate the effects of varying observation duration and session duration on the accuracy of the UT1-UTC estimate from this network. The ideal location for a 4th station on continental Australia is also evaluated under the context of optimising UT1-UTC performance, with north-eastern Tasmania providing the greatest increase to UT1-UTC accuracy. Finally, we investigate the effect of adding the Warkworth 12-metre into the network, which provides an efficient increase to UT1-UTC performance and would be an ideal addition pending a future VGOS upgrade for the station. Graphical Abstract