1. Quasi-Periodicity in the Parsec-Scale Jet of the Quasar 3C345 - A High Resolution Study using VSOP and VLBA - In collaboration with: J.A. Zensus A. Witzel T.P. Krichbaum A.P. Lobanov E. Ros

2. Content of the Talk The Quasar 3C345 Overview Observations Kinematic study of the jet Flux density study of the jet Merging of Galaxies The model Outlook

3. The Quasar 3C345 - Overview - z=0.595, m=16 arcsec scales compact region at the base of a 4''jet; diffuse steep-spectrum halo mas scales VLBI monitoring since 1979  long time study core-jet structure core (D): unresolved, optically thick, flat spectrum, stationary (Bartel et al. 1986) jet: 11 components (C1-C11), different curved trajectories, variable superluminal speed (2-20c) DC9C8C7 C5 C4 C3

4. 4 Epochs: 1.6GHz VSOP 4 Epochs: 5GHz VSOP 7 Epochs: 22GHz VLBA 9+5 Epochs: 43GHz VLBA

5. Jet Kinematics: Core -Shift

6. Jet Kinematics: Trajectory of C7

7. Jet Kinematics: Trajectories of C8, C9

8. Jet Kinematics: Trajectories of C10, C11

9. Kinematics Jet Kinematics: Trajectories 9 years later

10. Jet Kinematics: Ejection Position Angle T = 8-10 years P.A. ej = 2.6°  0.3° /year

11. Jet Parameters: Min. Lorentz Factor

12. Jet Parameters: Constant Lorentz Factor

13. Jet Parameters: Increasing 

14. Flux Density Evolution: C7/C8/C10/C11

15. Trajectory part of Flux Density Peaks

16. Evolution of the Flux Density Peaks

17. Merging of Galaxies  Binary Black Holes?

18. Binary Black Hole Model

19. Binary Black Hole model of Lobanov & Roland 2002: C7: Kinematic and flux density evolution C5-to-C8: Obs:  P.A. ej = 28  14   BBH:  P.A. ej = 27  peak-to-peak: Obs:  P.A. ej = 26  7  BBH:  P.A. ej  = 30 

20. Results 1 Three new ejected jet components C9, C10 and C11. 2 Different component trajectories but similarity of the C5 and C8 trajectory: Equivalent points are about 8-10 years later for C8 than for C5. 3 Component ejection angles vary: Quasi-periodicity of 8-10 years. Long-term variation of P.A. ej = 2.6°  0.3° / year 4 Acceleration of the jet components. Lorentz factor rises from 3 to 16. 5 Doppler factor rises from 5 to 30. 6 Angle to the line of sight changes down to: 3.5°  0.2°. 7 Component flux density peaks due to Doppler boosting. 8 Component flux density peaks show quasi-periodicity with a period of about 9 years. 9 Observations match with Binary Black Hole model of Lobanov & Roland 2002: Orbital period in observers frame: 8.5 years. Precession period in observers frame: 125 years (2.9° / year)

21. Outlook 1.Continue VLBI monitoring to pursue our intensive study of this particular quasar. 3.Test the stationarity of the core: Phase-referencing program started with the VLBA to the nearby quasar NRAO 512 (  0.5° apart) at 7 mm and 3 mm in 2002. 4.Test Binary Black Hole model with jet components C8 and C9. 2. Several observations have been made at  = 3 mm to supplement our extensive study at core distances smaller than 100  arcsec.

22. Flare Model, Lobanov & Zensus Lobanov & Zensus 1999

23. Spectral Index Maps

24. Components

25. Core -Shift

26. Flux Density Evolution of C9

27. 1.61.6 Precision of the Trajectories

28. 1.61.6  x  3 mas r  14 pc r  3 pc

29. 1.61.6 Precision of the Trajectories  x  mas r  pc r  3 pc

30. 1.61.6 Precision of the Trajectories Small changes in the observed trajectories lead to big differences in derived jet parameters!  Need high-precision trajectories

31. The inner jet (C10-C7) of 3C345