03/000 Future operations of the AuScope network Australian Government Geoscience Australia
Status Geoscience Australia 28 September 2009 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
Outline Geoscience Australia 28 September 2009 Scientific background Potential goals Operational plans Scheduling issues
Scientific background Geoscience Australia 28 September 2009
ICRF defining sources (1998) Geoscience Australia 28 September 2009
ICRF2 defining sources (2009)
Proper motion is not a part of the ICRS/ICRF Geoscience Australia 28 September 2009
4C September 2009 The longer period of time, the better proper motion
Apparent proper motion (raw data) (86 the most observed sources; 200 sess, 15 obs) 28 September 2009
Apparent proper motion 28 September 2009
Apparent proper motion (raw data, 687 sources; ≥3 sess, ≥3 obs) 28 September 2009
Apparent proper motion (scale changed!) 28 September 2009
Second harmonic (interpretation) 25 September 2009 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
Geoscience Australia 25 September 2009 ParametersDipole ( μasec/year ) Dipole + rotation + second degree ( μasec/year ) a(1)2.1 +/ /- 1.3 a(2) / /- 1.3 a(3)2.5+/ /- 1.5 a15.7 +/ /- 1.3 RA (deg)278 +/ /- 6 DE (deg) 9 +/ /- 8 (1) 6.3 +/- 1.5 (2) 2.6 +/- 1.5 (3) /- 0.8 E(2,0)7.2 +/- 1.4 E(2,1)-5.5 +/- 1.5 E(2,-1)-4.8 +/- 1.5 E(2,2)-0.2 +/- 0.9 E(2,-2)-2.5 +/- 1.1 M(2,0)-4.8 +/- 0.9 M(2,1)-0.9 +/- 1.3 M(2,-1)-8.7 +/- 1.4 M(2,2)-5.5 +/- 1.3 M(2,-2)7.1 +/- 1.5 Estimates of spherical harmonics
Apparent proper motion (dipole systematic) 28 September 2009
Apparent proper motion (rotational systematic) 28 September 2009
Apparent proper motion (second degree systematic) 28 September 2009
Apparent proper motion (resultant systematic – 16 parameters) 28 September 2009
Apparent proper motion (dipole systematic in Galactic coordinates) 28 September 2009 Sub-μas/year level !?Amplitude /- 0.5 μas/year
Potential goals Geoscience Australia 28 September 2009
Systematic effects Dipole effect 14 ± 1( 0.5 ) μas/year (Galactic attraction) Rotation -18 ± 1 μas/year (precession constant?) 28 September 2009 Second degree systematic 17 ± 4 μas/year Hubble expansion anisotropy or primordial GW?
Second harmonic (interpretation) 28 September 2009 Geodetic VLBI data Gwinn et al (1997) – gravitational waves density Other observations Either the primordial GW are strong, or another explanation to be found
Second harmonic (interpretation) 28 September 2009 E(2,2) = /- 0.9 μas/year E(2,0) = 7.2 +/- 1.4 μas/year = 36 km/sec*Mpc Hubble constant anisotropy? Too large anisotropy !!!
“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)= km/sec with respect to CMB Geoscience Australia 28 September 2009 Another cosmologic dipole effect
sources 10 μ as/year sources 1 μ as/year … 2020 >2000 sources 0.1 μ as/year 28 September 2009 Future for the dipole?
Geoscience Australia 28 September 2009 Redshift dependence of the cosmologic proper motion LCDM model (Kardashev, 1986)
LMC – 50 kpc; π = 20 µas strong compact radio source for VLBI 28 September 2009 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?
We can’t reach the goals without the AuScope network Geoscience Australia 28 September 2009 More determined operational plan needs to be developed
Operational plans Geoscience Australia 28 September 2009
AuScope project Geoscience Australia 28 September 2009 Simulation shown the 1-mm precision for the four new radio telescopes is achievable Auckland – Yarragadee ~5.300 km Auckland – Katherine ~4.700 km
Geoscience Australia 28 September 2009 Longer baselines ~ km Hartrao ?
Future Geoscience Australia 28 September 2009 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
Scheduling issues Geoscience Australia 28 September 2009
Position of the radio sources observed by Parkes in September 2009 Special scheduling ??
Astrometry Geoscience Australia 28 September 2009 Focusing on the area around the South Pole. Though, all sources are available (from -90 to +90)
Geodesy Geoscience Australia 28 September 2009 ITRF in the Southern Hemisphere Trans-Australian and trans-Tasmanian baselines Traditional scheduling for a regional VLBI network
Conclusion Geoscience Australia 28 September 2009
Conclusion Geoscience Australia 28 September We could estimate the systematic effects with accuracy 1 µas/y or even better; 2.New scientific goals could be challenged; 3.The AuScope network would play a key role; 4.Dedicated programs focused on the astrometry of the Southern Hemisphere to be run; 5.26 sessions/year operated by IVS; 6.5 ANZ dishes Asian dishes (+ Hartrao) – tbd; 7. Starts on January, 2010
Everybody is welcome! 28 September 2009 Sixth General IVS Meeting Hobart, 8-10 February, 2010 University of Tasmania
Thank you! 28 September 2009
Operational issues Geoscience Australia 28 September As a part of international network 2.Asia-Pacific network on weekly basis 3.26 sessions/year ANZ dishes Asian dishes (from 2010?) 5.Scheduling and correlation: provided by IVS 6.Some change in the whole IVS schedule required 7.Approval by the IVS OPC 8.More current IVS programs?
Operational issues Geoscience Australia 28 September As independent network (mostly for geodesy) 2.Flexible schedule 3.30 sessions/year ? 4.Scheduling ? 5.Correlation – Curtin? (local resources) 6.Data to be stored in the IVS database 7.Local Program Committee ?
Second harmonic (interpretation) 2. Kinematics interpretation – diagonal elements of the expansion tensor 25 September Gravitational waves – Pyne et al. (1996), Gwinn et al. (1997) - for generalized Hubble law
Kinematic interpretation 25 September 2009 The Hubble law Anisotropy and non- zero systematic
Second harmonic (Kristian and Sachs, 1966) 25 September 2009 σ – Shear (deformation) ω - Rotation E - ‘Electric’ gravitational waves H - ‘Magnetic’ gravitational waves Dependent on distance
Second harmonic (interpretation) 25 September 2009 Depends on distanceDepends on Z Different ranges of Z – plot Mean root squared amplitude
Geoscience Australia 25 September 2009 Magnitude of the second degree harmonics versus redshift Out of model
Second harmonic (interpretation) 25 September 2009 Gwinn et al (1997) – gravitational waves density E(2,2) = /- 0.9 μas/y E(2,-2) = /- 0.9 μas/y M(2,2) = / 1.3 μas/y M(2,-2) = 7.1 +/- 1.5 μas/y