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1 Michael Bietenholz, Hartebeesthoek Radio Observatory, South Africa VLBI of Supernovae and Gamma Ray Bursts.

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Presentation on theme: "1 Michael Bietenholz, Hartebeesthoek Radio Observatory, South Africa VLBI of Supernovae and Gamma Ray Bursts."— Presentation transcript:

1 1 Michael Bietenholz, Hartebeesthoek Radio Observatory, South Africa VLBI of Supernovae and Gamma Ray Bursts

2 2 Dr. Michael Gaylard

3 3 Resolution: we can resolve the explosive outflows. Normal supernova: km/s = 0.4 mas/yr at 10 Mpc, relativistic supernova or GRB, c = 0.6 mas/yr at 100 Mpc Determine ejecta speed Nature and geometry of the ejecta – jets? Clumpiness? Bipolar ejections? Radio emission is usually due to the interaction of the ejecta with the surrounding material: from interaction we can learn about both ejecta and the surrounding material Evolution of SN shells, shock acceleration, eventual merging with ISM Compact remnant of a core-collapse SN? Supernova rates, especially in dusty environments Direct distances with the expanding shock front method – out to Virgo cluster Introduction: Why Image Supernovae and GRBs with VLBI?

4 4 Supernovae: Radio Detection of SNe Optical: several hundred SNe are detected each year Radio: Only core collapse (Type II, Type I b/c) detected to date (limits in Ia next talk). Only a few SNe detected each year in radio; total radio detections to date ~60 Even fewer have been resolved by radio observations - so every VLBI observation is of great value

5 5 RSNe Detected with VLBI NameTypeHost galaxy Distance (Mpc) Peak (mJy at 8 GHz) References SN 1978KIINGC 13134>100? Smith et al SN 1979CIIM Bartel & Bietenholz, Marcaide et al SN 1980KIINGC Bartel 1985 SN 1986JIINGC Bietenholz et al 2004 SN 1987AIILMC Jauncey, Ng, Manchester SN 1993JIIM Bietenholz, Bartel, Marcaide SN 1994IIcM Bietenholz & Bartel, unpublished SN 1996crIICircinus3.6~100 Bauer et al, Bartel et al in prep SN 2001emIb/cNGC Bietenholz, Paragi, Schinzel SN 2001gdIINGC Pérez-Torres et al 2008 SN 2003gkIbNGC Bietenholz et al 2013 SN 2003LIb/cNGC Soderberg et al 2005 SN 2004etIINGC Martí-Vidal et al SN 2007grIb/cNGC <~ 1 Paragi et al 2007 SN 2007uyIbNGC van der Horst 2011 SN 2008D BLIb/cNGC Soderberg, Bietenholz Paragi SN 2008izII?M Brunthaler et al 2010 SN 2009bb BLIb/cNGC Bietenholz et al 2010 SN 2011dhIIbM Bietenholz et al, Martí-Vidal et al Approximately 30 RSNe with flux densities > 1 mJy have been detected in radio, and >100 have upper limits.

6 6 RSNe Detected with VLBI NameTypeHost galaxy Distance (Mpc) Peak (mJy at 8 GHz) References SN 1978KIINGC 13134>100? Smith et al SN 1979CIIM Bartel & Bietenholz, Marcaide et al SN 1980KIINGC Bartel 1985 SN 1986JIINGC Bietenholz et al 2004 SN 1987AIILMC Jauncey, Ng, Manchester SN 1993JIIM Bietenholz, Bartel, Marcaide SN 1994IIcM Bietenholz & Bartel, unpublished SN 1996crIICircinus3.6~100 Bauer et al, Bartel et al in prep SN 2001emIb/cNGC Bietenholz, Paragi, Schinzel SN 2001gdIINGC Pérez-Torres et al 2008 SN 2003gkIbNGC Bietenholz et al 2013 SN 2003LIb/cNGC Soderberg et al 2005 SN 2004etIINGC Martí-Vidal et al SN 2007grIb/cNGC <~ 1 Paragi et al 2007 SN 2007uyIbNGC van der Horst 2011 SN 2008D BLIb/cNGC Soderberg, Bietenholz Paragi SN 2008izII?M Brunthaler et al 2010 SN 2009bb BLIb/cNGC Bietenholz et al 2010 SN 2011dhIIbM Bietenholz et al, Martí-Vidal et al Approximately 30 RSNe with flux densities > 1 mJy have been detected in radio, and >100 have upper limits.

7 7 Radio Lightcurves (SN 1993J) Typical pattern seen in SNe with frequency- dependent rise and then a power-law decay after the supernova has become optically thin Increase in the steepness of the decay at t ≈ 2500 days (Bartel et al 2002)

8 8 VLBI Movie of SN 1993J Global Array VLBI at 8.4 GHz, then 5 GHz and 1.6 GHz for last epochs 35 Epochs of VLBI

9 9 Deceleration Radius scaled by t 0.8 to show deviations from powerlaw expansion Bietenholz et al 2010

10 GHz 6 Mar 2010, day 6187 ~ 16 years after the explosion Explosion Center μJy/beam Global array: 18 antennas (EVN + VLBA + GBT). Used in-beam calibrator technique Image background rms: 3.7 μJy/beam Radius: 5.1 × cm (34,000 AU; 0.16 pc) Expanding at ~7,500 km/sec Limit on a PWN at centre? –50 μJy at 1.6 GHz = 25% of Crab Nebula –Bietenholz et al 2003: 50 μJy at 8.4 GHz (stacked 3 epochs, ) –Marti-Vidal & Marcaide 2014: 102 μJy at 5.0 GHz (stacked images) Bietenholz et al, in prep

11 11 Central Component in SN1986J Central component turned on at age ~15 yr  0.8 milli-arcsec (10 17 cm) 200 × the current radio luminosity of the Crab Nebula at 15 GHz Bietenholz, Bartel & Rupen 2004 Multi-frequency VLBI Image: Contours, red: 5 GHz Blue  white: 15 GHz

12 12 Central Component in SN1986J Bietenholz, Bartel & Rupen 2004 Multi-frequency VLBI Image: Contours, red: 5 GHz Blue  white: 15 GHz Youngest Neutron Star or Black Hole?

13 13 SN 1987A Comparison of VLBI image to optical and X-ray images. Contours: VLBI at 1.7 GHz, 0.5, 1.5, 3, and 5 mJy/beam. Ng et al 2011

14 14 SN 1987A Comparison of VLBI image to optical and X-ray images. Contours: VLBI at 1.7 GHz, 0.5, 1.5, 3, and 5 mJy/beam. Ng et al 2011

15 15 ULIRGs: Supernova Factories Arp 220 (Conway et al), Arp 299 (Bondi, Neff, Ulvestad et al.), IRAS (Romero-Cañizales, Pérez-Torres et al.) High Sensitivity Array observations at 14 and Global VLBI at 8.4 GHz 17 sources detected, mostly resolved at 14 GHz VLBI crucial to distinguishing starburst and AGN Conway et al 2010

16 16 Relativistic Expansion: SNe and GRBs Image: Saxton Long Duration GRB’s associated with Type Ibc supernovae Collapse of massive star into a black hole powers highly relativistic jet GRB’s are jets oriented near the line of sight The jets not near the line of sight may be visible in radio

17 17 Relativistic Expansion: SNe and GRBs Image: Saxton Long Duration GRB’s associated with Type Ibc supernovae Collapse of massive star into a black hole powers highly relativistic jet GRB’s are jets oriented near the line of sight The jets not near the line of sight may be visible in radio

18 18 SN 2009bb VLBI observations Peak brightness 613 μJy/bm, rms = 128 μJy/bm, VLBA, VLA, Hobart, Tidbinbilla 2009 Jun 12 (age = 85 days) 40 Mpc Upper limit on angular size = 0.64 mas = 1.74c S N bb Bietenholz et al 2010

19 19 Limits on Off-Axis Jets Off-axis jets could be detectable in the radio However, lower efficiency in par- ticle acceleration or lower magnetic field could dras- tically lower model curves Luminosity limits: Bietenholz et al 2014, and Soderberg et al 2006 (S2006) Bietenholz et al 2014 SN 2003gk

20 20 SN 2003gk VLBI Observations 8.4 GHz VLBA + Ef + Arecibo Age=~7.5 yrs (2011 Apr 11) Contours: 20, 30, 50, 70, 90% of peak of 86 μJy/ beam r = 1 light-year Bietenholz et al 2014

21 21 Limits on Off-Axis Jets Off-axis jets could be detectable in the radio However, lower efficiency in par- ticle acceleration or lower magnetic field could dras- tically lower model curves Luminosity limits: Bietenholz et al 2014, and Soderberg et al 2006 (S2006) Bietenholz et al 2014

22 22 VLBI Expansion Measurements: by Taylor et al. & Pihlstrom et al. show clear deceleration, with transition to non-relativistic regime at t ~ 1yr Relativistic Expansion: GRB (SN 2003dh) 22 Apr 2003 Size ~1 pc = 3 light years Taylor et al, 2004, 2005; Pihlstrom et al. 2007, Mesler et al 2012

23 23 VLBI Expansion Measurements: by Taylor et al. & Pihlstrom et al. show clear deceleration, with transition to non-relativistic regime at t ~ 1yr Relativistic Expansion: GRB (SN 2003dh) 22 Apr 2003 Size ~1 pc = 3 light years Speed of light Taylor et al, 2004, 2005; Pihlstrom et al. 2007, Mesler et al 2012

24 24 The Future of Supernova VLBI More sensitivity – follow supernova for longer Resolve older, more distant supernovae: Cas A is 1 μJy and 6 mas at 170 Mpc - fill in the gap between supernovae and supernova remnants Supernova rates → star formation rates Pop III Hypernova GRBs and orphan afterglows

25 25 VLBI Supernova Gallery SN 1987ASN 1993J SN 1996crSN 2008izM82SN 2011dh SN 1996cr, 1993J, SN1986J, SN1979C: Bietenholz, Bartel et al; SN 2008iz Brunthaler et al 2010; M82 supernova/SNR: McDonald, Beswick, Argo et al SN 1979CSN 1986J

26 26

27 27 Comparison of RSNe & SNRs McDonald et al., 2001


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