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

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

The VLBI concept Resolution /  D ! cm to mm ! cm to mm D ! 10 4 km Beats HST in a factor 10 2 ! Radio interferometry with unlimited baselines No link between antennas Uses antennas built for other reasons

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

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? 

VLBI science samples 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 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

Active Galactic Nuclei

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)

The 2cm Survey – AGN Kinematics 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)

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)

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

Young Supernova Remnants

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

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

Type I b/c, II SNe Type Ia SNe

Type II SNe show H lines early in their spectra

Radio SN models Power law: N(E)=N 0 E -p Environment density:  / r -n Radius of the (self-similar) expanding SN: R / t m, with m=(n-3)/(n-2) Mini-shell model (Chevalier 1982) S /  t   =(1-p)/2,  =-(3-3m-  )

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

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

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

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

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

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)

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

SN 1986J in NGC 891 Mean angular size » 4.7 mas (0.22 pc) ! v » 6300 km s -1 between and R / t m, 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 v wind =10 km s -1, SN 1986J samples the CSM at time » yr; dM/dt » 2 £ M ¯ yr -1 ! M swept » 2.2 M ¯ Momentum conservation implies that M env ¸ 12 M ¯ Single star scenario favoured

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

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

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

Beam = 1.23 x 0.51 mas Mpc ~ 0.11 pc 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 ) – – Pérez-Torres et al., MNRAS (2005)

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) GALEX: UV image

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)

SNR in M mas ~ 1 lt-yr

in M 82 Expansion speed 9850 km/s Free expansion known since Probable explosion in the 1960s Low pressure region?

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

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

SN 1979C – VLBI results Strong deceleration phase v wind =10 km s -1 dM/dt=1.2 £ M ¯ yr -1 m=0.62 (strong interaction with CSM, s=2,  CSM / r -s ) t break =6 § 2 yr M swept =1.6 M ¯ M env =0.9 M ¯ Binary star scenario favoured

M 81 on April 26 th 1993 SN 1993J

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 km s -1 Deceleration discovered. Marcaide et al. Nature 373, (1995)

(Fransson, Lundqvist & Chevalier 1996, ApJ, 461, 993) SN 1993J in M81: wind doesn‘t go as s=2 (  / r -s ) Light curve at 15 GHz

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

Total flux density decreases to < 1 mJy Observations at 3.6, 6 and 21 cm Global array VLBI observations since its explosion

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.

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

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

SN1979C SN1986J SN2001gd SN1993J Distance (Mpc) Time since explosion (yr)» 25 » (L 6cm / L 6cm SN1993J ) 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) / (M sun /yr) »10 -4 » 2 x ? » 5 x Deceleration parameter (m) ? » 0.83 Asymmetric expansion? No Yes ? No (<5%) Circumstellar medium --- clumpy ? » smooth M swept / M sun ? » 0.4 M env / M sun ? » Explosion scenario Binary Single ? Binary Magnetic field amplification Turbulent ? Turbulent t break (years) 6§ » 1 Summary on young SNR Compiled by M. A. Pérez-Torres

On VLBI arrays…

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 ?

Adding the Kashi telescope to the EVN…

EVN Sensitivities 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 Image thermal noise 150min integration time l6cm 256 Mbps rate

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