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VLBI observations: from AGN to young SNR

VLBI observations: from AGN to young SNR. Picture: E. Middelberg (MPIfR). Eduardo Ros & J. Anton Zensus MPIfR, Bonn, Germany Kashi, Sep 9 th 2005. The quest for resolution. Atmosphere gives 1" limit without corrections which are easiest in radio. Jupiter and Io as seen from Earth

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VLBI observations: from AGN to young SNR

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  1. VLBI observations: from AGN to young SNR Picture: E. Middelberg (MPIfR) Eduardo Ros & J. Anton Zensus MPIfR, Bonn, Germany Kashi, Sep 9th 2005

  2. The quest for resolution Atmosphere gives 1" limit without corrections which are easiest in radio Jupiter and Io as seen from Earth 1 arcmin 1 arcsec 0.05 arcsec 0.001 arcsec Simulated with Galileo photo

  3. The VLBI concept • Resolution / /D ! cm to mm D ! 104 km • Beats HST in a factor 102 ! • Radio interferometry with unlimited baselines • No link between antennas • Uses antennas built for other reasons

  4. Beyond the Earth Limits: Space VLBI • VSOP Mission (Japan, 1997-today) – 8 m dish, 23,000 km orbit • Projects: • ARISE (USA) • VSOP-2 (JP) • RadioAstron (RUS)

  5. Pushing towards high frequencies: millimetre VLBI • Successful transatlantic detections up to 2mm • Regular operations of a 3mm network: Global Millimetre VLBI Array • Pushing towards 5/10 as resolutions: imaging the event horizon in BHs? http://www.mpifr-bonn.mpg.de/div/vlbi/globalmm/index.html

  6. VLBI science samples Jet formation Jet dynamics and magnetic fields Detect survey sources, distinguish starbursts from AGN Accurate proper motions Accretion disks and extra galactic distances Stellar environments Plate motions, EOP, reference frames CAPABILITY EXAMPLE SCIENCE High resolution continuum Movies and polarization Phase referencing to detect weak sources Phase referencing for positions High resolution spectral line Spectral line movies Geodesy and astrometry

  7. Active Galactic Nuclei

  8. 3C 120 – the movie • Bottom: Contours intensity / Color polarized flux • Top: Color intensity / Lines B vectors • Resolution 50 as • Intensity polarization variations suggest jet-cloud interaction Gómez et al., Science 289, 2317 (2000)

  9. The 2cm Survey – AGN Kinematics • 1994-2001 measurements • 110 sources studied • Typical speeds between 0 and 15c, up to 34c • Speed measurements consistent with Doppler factors var calculated from variability • Similar speeds within the same jet • Data not consistent with ballistic models • Many jets show bends and twists, 30% of features show non-radial motions • EGRET sources show faster speeds than non-EGRET Kellermann et al. ApJ 609, 539 (2004)

  10. The twin jets in NGC 1052 • The radio galaxy NGC 1052 shows two twin jets with mildly relativistic plasma travelling at 0.25c. • Movie produced from single VLBA observations at the 2cm Survey over almost 10 yr Movie: M. Kadler & Eduardo Ros (MPIfR)

  11. Jet: VLBI imaging Accretion disk: X-ray spectroscopy AGN at pc scales

  12. Young Supernova Remnants

  13. 1st observation: 05 Jul 1054 VLT Observations, 1999 SN 1054 – Crab Neula Chaco Canyon Anasazi

  14. What can we learn from RSN • Interaction properties of the shock and the circumstellar matter (CSM): clumps, shell, etc. • Shock front: Rayleigh-Taylor instabilities, particle acceleration mechanism, etc. • Progenitor system (single, binary) • Wind properties: mass-loss history

  15. Type Ia SNe Type I b/c, II SNe

  16. Radio SN models • Power law: N(E)=N0E-p • Environment density:  / r-n • Radius of the (self-similar) expanding SN: R / tm, with m=(n-3)/(n-2) • Mini-shell model (Chevalier 1982) S / t =(1-p)/2, =-(3-3m-)

  17. Radio SN models Time evolution Flux density at 5 GHz at t=1 day+t0 Optical depth Spectral index Standard model Weiler & Van Dyk Attenuation from a continous medium Attenuation from a clumpy medium Thermal, ionised hydrogen Optical depth at 5 GHz at t=1 day+t0 Time evolution, 0=5/3

  18. VLA (Sort of) canonical RSNe 1.4 GHz 1.4 GHz 1.4 GHz 5 GHz 5 GHz 8.4 GHz Type Ib SN1983N @ 1.4 and 5 GHz Type Ic SN1990B @ 1.4, 5, and 8.4 GHz Taken from Weiler et al. (2002)

  19. …and less canonical RSNe 5 GHz 1.4 GHz 1.4 GHz 5 GHz 15 GHz Type II SN1979C @ 1.4, 5, and 15 GHz Type II SN1980K @ 1.4 and 5 GHz (from Weiler et al. 2002)

  20. SN 1987A in the Large Magellanic Clouds Image: Hubble Space Telescope Heritage

  21. SN 1987A • Quick flux density evolution and low Brightness: evolution with the environment • VLBI shows a rapid expansion (≥ 19000 km/s) • SN 1987A was unexpectedly brighter in radio at 1990.5 • Complex environment is responsible

  22. SN 1987A in the LMC, radio Age: 5810 days; Expansion: 3500±100 km s-1, X-ray measurements, 5000±1000 km s-1 Staveley-Smith et al. (2004)

  23. VLA, Feb. 1999 NGC 891* SN1986J SN 1986J in NGC 891 • Explosion: 1982 • First discovered in radio (1986), afterwards, ist optical counterpart • VLBI structure is non-symmetric Nucleus SN1986J VLBI (Pérez-Torres et al. 2002, MNRAS, L23)

  24. SN 1986J in NGC 891 • Mean angular size » 4.7 mas (0.22 pc) ! v» 6300 km s-1 between 1998.74 and 1999.14 • R/ tm, m=0.90§0.06 (very close to free expansion) • Anisotropic brightness distribution: shell structure likely due to a collision with a clumpy or filamentary wind • For standard vwind=10 km s-1, SN 1986J samples the CSM at time » 11000 yr; dM/dt » 2£ 10-4 M¯ yr-1! Mswept» 2.2 M¯ • Momentum conservation implies that Menv¸ 12 M¯ • Single star scenario favoured

  25. SN 1986J in NGC 891 A bright, compact radio component has been discovered, with an inverted radio spectrum Bietenholz et al. Science

  26. SN 2001gd in NGC 5033 NGC 5033 SN2001gd Image taken on 13 Jan 2002 Pre-discovery image

  27. SN 2001gd at  3.6 cm 26.02.2002 VLA 3.6 mJy VLBI 08.04.2003 1.0 mJy VLBI Pérez-Torres et al. (MNRAS, 2005)

  28. VLBI image of SN 2001gd • Angular estimates: • Optically thick source: • a=0.37§0.02 mas • b/a=0.45§0.22 mas • Optically thin sphere: • 0.39§0.01 mas • Optically thin ellipsoid • a=0.41§0.02 mas • b/a=0.45§0.21 mas Distance Inferred velocities (Mpc) (1000 km s-1) 13.5 14.4 – 16.3 21.6 23 - 26 Beam = 1.23 x 0.51 mas 1 mas @ 21.6 Mpc ~ 0.11 pc Pérez-Torres et al., MNRAS (2005)

  29. GALEX: UV image The galaxies M 81 & M 82 • M 82: Starburst galaxy • M 81: Spiral galaxy M82 M81 Images: APOD 12/30/2004 (left) & 04/01/2004 (right)

  30. The starburst galaxy M 82 • More than 50 radio sources, most of them are SNR. • Size from 1 to 15 lt-yr Pedlar et al. (2004)

  31. SNR in M 82 25 mas ~ 1 lt-yr

  32. 43.31+592 in M 82 • Expansion speed 9850 km/s • Free expansion known since 1972. Probable explosion in the 1960s • Low pressure region?

  33. SN1979C in M 100 • SN 1979C in M100 (D=16.1 Mpc) • texplosion=April 4th 1979 • Vexpansion=9200 km s-1 at t» 45d • Type II SN-L • Progenitor: binary system • Mprogen» 17-18 M¯(Van Dyk et al. 1999) • Radio emission interpreted within the mini-shell model (Chevalier 1982)

  34. VLBI observations, 18cm, 20 yr after explosion • Source size is model dependent: • Optically thick disk: 4.57§0.25 mas • Optically thin shell of width 0.3 rout: 3.60§0.17 mas • Optically thin ring: 3.10§0.14 mas • Best model: optically thin shell (Marcaide et al. 2002, A&A, 384, 408)

  35. Strong deceleration in SN 1979C (Marcaide et al. 2002, A&A, 384, 408)

  36. SN 1979C – VLBI results • Strong deceleration phase • vwind=10 km s-1 • dM/dt=1.2£ 10-4 M¯ yr-1 • m=0.62 (strong interaction with CSM, s=2, CSM/ r-s) • tbreak=6§2 yr • Mswept=1.6 M¯ • Menv=0.9 M¯ • Binary star scenario favoured

  37. SN 1993J M 81 on April 26th 1993

  38. SN 1993J in M 81 • Discovery of radio shell structure (Marcaide et al. Nature, 1995) • First supernova movie (Marcaide et al. Science, 1995) • Expansion at 15000 km s-1 Deceleration discovered. Marcaide et al. Nature 373, 44-45 (1995)

  39. Deceleration in the expansion of SN 1993J R ~ tm m = (n - 3) / (n-s) (Marcaide et al. 1997,Ap.J.486, L31) V ~ 9000 km/s after ~ 1300 days

  40. Last results on the SN 1993J evolution • The angular expansion has now been monitored for 12 years: • Changes in the deceleration, • Dependence of the angular size with the wavelength • Spectral index evolution. • The shell is circular and the expansion of the shock front is isotropic.

  41. SN 1993J – The movie Young Supernova Remnant after the explosion of SN 1993J in M81 twelve years and half ago Marcaide et al. (1995-2005)

  42. SN 1993J – VLBI results • Self-similar expansion with m=0.86 • Pre-supernova wind with s=1.66 (CSM/ r-s) • Outer layers of progenitor have n=11.2 (EJ» r-n) • Width of radio shell » 0.3 £ outer radius • No emission from any central source > 0.5 mJy • No evidence for large Rayleigh-Taylor instabilites

  43. Summary on young SNR SN1979CSN1986JSN2001gdSN1993J Distance (Mpc) 16.1 9.6 21.6 3.63 Time since explosion (yr)» 25 » 19 <1 >12 (L6cm / L6cmSN1993J)peak» 1.6 » 13 »2 1 Resolved by VLBI? Not yet Yes Not yet Yes Optically thin phase? Yes Yes Likely yes Yes Radio brightness structure shell distorted shell --- ~smooth shell (dM/dt) / (Msun/yr)»10-4» 2 x 10-4 ?» 5 x 10-5 Deceleration parameter (m) 0.62 0.90 1.0? » 0.83 Asymmetric expansion? No Yes ? No (<5%) Circumstellar medium--- clumpy ?» smooth Mswept / Msun 1.6 2.2 ? » 0.4 Menv / Msun 0.9 12 ? » 0.2-0.4 Explosion scenario Binary Single ? Binary Magnetic field amplification Turbulent ? Turbulent tbreak (years) 6§2 ---- ---- » 1 Compiled by M. A. Pérez-Torres

  44. On VLBI arrays…

  45. The European VLBI Network • Not shown: Arecibo (PR), Shanghai & Urumqi (CN), Hartebeesthoek (ZA) • Oncoming new telescopes: • 40 m dish – Yebes, Guadalajara, Spain • 70 m dish – Cagliari, Sardinia, Italy • 100 m Kashi telescope – China ?

  46. Adding the Kashi telescope to the EVN…

  47. Eb+Mc+On+Tr+Jb2+Cm+Wb+Nt+Sh+Ur+Hh ! 32 Jy Sh+Ur+Hh ! 452 Jy Eb+Mc+On+Tr+Jb2+Cm+Wb+Nt+Sh+Ur+Hh+Kashi! 18 Jy Sh+Ur+Hh+Kashi! 74 Jy EVN Sensitivities • Image thermal noise • 150min integration time • 6cm 256 Mbps rate

  48. International Max Planck Research School for Radio and Infrared Astronomy at the Universities of Bonn and Cologne • Graduate school program • 38 schools so far in Germany • Partnership MPIfR-University of Bonn • 26 students from 14 nationalities • Worldwide call for applications http://www.mpifr-bonn.mpg.de/imprs

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