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Australian Government Geoscience Australia. Future operations of the AuScope network. 03/000. Status. Hobart (26 m) 50 sessions/year Parkes (64 m) 3-6 sessions/year Tidbinbilla or DSS45 (34 m) n/a

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03/000

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  1. Australian Government Geoscience Australia Future operations of the AuScope network 03/000

  2. Status • Hobart (26 m) 50 sessions/year • Parkes (64 m) 3-6 sessions/year • Tidbinbilla or DSS45 (34 m) n/a • Hobart (12 m) – 2009(10) up to 180 sessions/year • Yarragadee (12 m) – 2010 up to 180 sessions/year • Katherine (12 m) – 2010 up to 180 sessions/year • Auckland (12 m) – 2009(10) up to 60 sessions/year Geoscience Australia 28 September 2009

  3. Outline • Scientific background • Potential goals • Operational plans • Scheduling issues Geoscience Australia 28 September 2009

  4. Scientific background Geoscience Australia 28 September 2009

  5. ICRF defining sources (1998) Geoscience Australia 28 September 2009

  6. ICRF2 defining sources (2009)

  7. Proper motion is not a part of the ICRS/ICRF Geoscience Australia 28 September 2009

  8. 4C39.25 The longer period of time, the better proper motion 28 September 2009

  9. Apparent proper motion (raw data)(86 the most observed sources; 200 sess, 15 obs) 28 September 2009

  10. Apparent proper motion 28 September 2009

  11. Apparent proper motion (raw data, 687 sources; ≥3 sess, ≥3 obs) 28 September 2009 28 September 2009

  12. Apparent proper motion (scale changed!) 28 September 2009 28 September 2009

  13. Second harmonic (interpretation) Kristian and Sachs (1966) – proper motions in general relativity in the “dust-filled” Universe An apparent proper motion may arise, loosely speaking, either from a “real” motion of the source or from a curvature of space time between the source and the observer 25 September 2009

  14. Estimates of spherical harmonics Geoscience Australia 25 September 2009

  15. Apparent proper motion (dipole systematic) 28 September 2009

  16. Apparent proper motion (rotational systematic) 28 September 2009

  17. Apparent proper motion (second degree systematic) 28 September 2009 28 September 2009

  18. Apparent proper motion (resultant systematic – 16 parameters) 28 September 2009 28 September 2009

  19. Apparent proper motion (dipole systematic in Galactic coordinates) Amplitude 12.8 +/- 0.5 μas/year Sub-μas/year level !? 28 September 2009

  20. Potential goals Geoscience Australia 28 September 2009

  21. Systematic effects • Dipole effect 14 ± 1(0.5)μas/year (Galactic attraction) • Rotation -18 ± 1μas/year (precession constant?) Second degree systematic 17 ± 4μas/year Hubble expansion anisotropy or primordial GW? 28 September 2009

  22. Second harmonic (interpretation) Gwinn et al (1997) – gravitational waves density Geodetic VLBI data Other observations Either the primordial GW are strong, or another explanation to be found 28 September 2009

  23. Second harmonic (interpretation) Hubble constant anisotropy? E(2,2) = -0.2 +/- 0.9 μas/year E(2,0) = 7.2 +/- 1.4 μas/year=36 km/sec*Mpc Too large anisotropy !!! 28 September 2009

  24. “The solar system’s velocity relative to the CMB will cause every extragalactic radio source to undergo a regular proper motion” (Kardashev, 1986). V(Sun)=300-400 km/sec with respect to CMB Another cosmologic dipole effect Geoscience Australia 28 September 2009

  25. 1996 499 sources 10 μas/year2008 687 sources 1 μas/year… 2020 >2000 sources 0.1 μas/year Future for the dipole? 28 September 2009

  26. Redshift dependence of the cosmologic proper motion (Kardashev, 1986) 2008 2020 LCDM model Geoscience Australia 28 September 2009

  27. LMC – 50 kpc; π = 20 µasstrong compact radio source for VLBI Parallax measurement A water maser could be added to the list of observed sources (26 sessions/year)We could get the parallax for ~5 years 8.4 GHz or 22GHz? 28 September 2009

  28. We can’t reach the goals without the AuScope network More determined operational plan needs to be developed Geoscience Australia 28 September 2009

  29. Operational plans Geoscience Australia 28 September 2009

  30. AuScope project Auckland – Yarragadee ~5.300 km Auckland – Katherine ~4.700 km Simulation shown the 1-mm precision for the four new radio telescopes is achievable Geoscience Australia 28 September 2009

  31. Longer baselines ~ 8-9.000 km Hartrao ? Geoscience Australia 28 September 2009

  32. Future The new geodetic VLBI network would play a leading role in making the ICRF in the Southern Hemisphere. It could work as an independent network or as a part of international network. • Astrometric program (26 sessions/year) • Geodetic program (NN sessions per year) only Australian and New Zealand antennas Geoscience Australia 28 September 2009

  33. Scheduling issues Geoscience Australia 28 September 2009

  34. Position of the radio sources observed by Parkes in 2004-2008 Special scheduling ?? 28 September 2009

  35. Astrometry Focusing on the area around the South Pole. Though, all sources are available (from -90 to +90) Geoscience Australia 28 September 2009

  36. Geodesy • ITRF in the Southern Hemisphere • Trans-Australian and trans-Tasmanian baselines Traditional scheduling for a regional VLBI network Geoscience Australia 28 September 2009

  37. Conclusion Geoscience Australia 28 September 2009

  38. Conclusion • We could estimate the systematic effects with accuracy 1 µas/y or even better; • New scientific goals could be challenged; • The AuScope network would play a key role; • Dedicated programs focused on the astrometry of the Southern Hemisphere to be run; • 26 sessions/year operated by IVS; • 5 ANZ dishes + 3-5 Asian dishes (+ Hartrao) – tbd; • 7. Starts on January, 2010 Geoscience Australia 28 September 2009

  39. Everybody is welcome! Sixth General IVS MeetingHobart, 8-10 February, 2010University of Tasmania 28 September 2009

  40. Thank you! 28 September 2009

  41. Operational issues • As a part of international network • Asia-Pacific network on weekly basis • 26 sessions/year • 3-4 ANZ dishes + 1-2 Asian dishes (from 2010?) • Scheduling and correlation: provided by IVS • Some change in the whole IVS schedule required • Approval by the IVS OPC • More current IVS programs? Geoscience Australia 28 September 2009

  42. Operational issues • As independent network (mostly for geodesy) • Flexible schedule • 30 sessions/year ? • Scheduling ? • Correlation – Curtin? (local resources) • Data to be stored in the IVS database • Local Program Committee ? Geoscience Australia 28 September 2009

  43. Second harmonic (interpretation) 1. Gravitational waves – Pyne et al. (1996), Gwinn et al. (1997) 2. Kinematics interpretation – diagonal elements of the expansion tensor - for generalized Hubble law 25 September 2009

  44. Kinematic interpretation Anisotropy and non-zero systematic The Hubble law 25 September 2009

  45. Second harmonic (Kristian and Sachs, 1966) σ – Shear (deformation) ω- Rotation E - ‘Electric’ gravitational waves H - ‘Magnetic’ gravitational waves Dependent on distance 25 September 2009

  46. Second harmonic (interpretation) Mean root squared amplitude Depends on distance Depends on Z Different ranges of Z – plot 25 September 2009

  47. Magnitude of the second degree harmonics versus redshift Out of model Geoscience Australia 25 September 2009

  48. Second harmonic (interpretation) Gwinn et al (1997) – gravitational waves density E(2,2) = -0.2 +/- 0.9 μas/y E(2,-2) = -2.5 +/- 0.9 μas/y M(2,2) = -5.5 +/ 1.3 μas/y M(2,-2) = 7.1 +/- 1.5 μas/y 25 September 2009

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