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Mass Loss Return From Stars to Galaxies 29 March 2012. Properties of Mass Loss f rom Supernova Progenitors Determined from Radio Observations. Nino Panagia ( STScI , INAF-CT, Supernova Ltd ). Mass Loss Return From Stars to Galaxies 29 March 2012.
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Mass Loss Return From Stars to Galaxies 29 March 2012 Properties of Mass Loss fromSupernova ProgenitorsDetermined from Radio Observations Nino Panagia (STScI, INAF-CT, Supernova Ltd)
Mass Loss Return From Stars to Galaxies 29 March 2012 Digging into the Past of Exploding Stars: Radio Observations of Supernovae Nino Panagia (STScI, INAF-CT, Supernova Ltd)
Radio Supernovae • Largely based on work done (over MANY years) in collaboration with: • Kurt W. Weiler (NRL) • Dick A. Sramek (NRAO) • Schuyler D. van Dyk (IPAC) • Marcos J. Montes (NRL) • Chris Stockdale (Marquette U) • Stuart Ryder (AAO) • Stefan Immler (GSFC) • et al… Nino Panagia Radio Supernovae
SN classification Ia: termonuclear explosion of a WD II-Ib/c: gravitational collapse of a massive star Nino Panagia Radio Supernovae
Radio Supernovae (RSNe) ~70 RSNe detected in the radio ~30 with light curves ~20 with extensive light curves Many upper limits (~300 ) Nino Panagia Radio Supernovae 6
Our most recent review on RSNe ARAA 40, 387, 2002 Nino Panagia Radio Supernovae
Why RSNe? The study of radio emission provides valuable insight into SN shock/CSM interaction • History of pre-SN evolution • Mass-loss rate and changes therein • Nature of the progenitor Nino Panagia Radio Supernovae
What RSNe? • All RSNe have in common: • Nonthermal synchrotron with high TB • Decrease in (l - dependent) absorption with time • Powerlaw flux density decline after max • Final approach to optically, thin constant a • Interesting variations: • Clumps or filaments in CSM • Possible binary companions Nino Panagia Radio Supernovae
Radio Supernovae • “Turn on”, first at high , progressing to lower • Power-law decline after maximum at each • Transition from “optically thick” spectral index (where S ~ + ) to an “optically thin” asymptotic value • Nonthermal emission with very high TB SN Ib SN II-L SN IIn Nino Panagia Radio Supernovae
Standard Model Physical Parameters(Chevalier 1984) } SNII • Red Supergiant (RSG) progenitor • Slow (10 km s-1), dense (10-6-10-4 Myr-1) wind • r-2 [ Mdot/(wwind r2)] density profile • CircumStellar Medium (CSM) ionized by SN UV/X-ray flash • Relativistic electrons & enhanced magnetic field arise from shock/CSM interaction • Ionized CSM provides initial absorption (f-f) • Synchrotron Self-Absorption (SSA) may play a role at very early times Nino Panagia Radio Supernovae
Circumstellar Interaction parameterized radio light curves [Weiler et al. 2002] K5, K6 = internal SSA and f-f optical depth on day 1 ( >105 K Nino Panagia Radio Supernovae
Circumstellar Interaction: Estimation of progenitor’s Mass-loss Rate (from f-f absorption) (Weiler et al. 1986, 1990, 2002, 2007) Nino Panagia Radio Supernovae
Type Ia Supernovae Nino Panagia Radio Supernovae
VLA Observations of SNIa Panagia et al 2006 • Observed 27 SNIa over 24 years of monitoring NO detection Nino Panagia Radio Supernovae
All SNIaat once The lowest 2 upper limit is about 3 10-8 M yr-1 Nino Panagia Radio Supernovae
The most StringentUpperLimits M < 310-8 M yr-1 Nino Panagia Radio Supernovae
Radio Constraints on SNIa Progenitors The theoretical requirement that accretion rates higher than 10-7 M yr-1are needed to make a WD mass exceed the Chandrasehkar mass combined with the radio upper limit to the mass loss rates < 310-8 M yr-1 : • Rules out accretion via stellar wind from a companion (accretion efficiency <30%) • Allows accretion via Roche lobe overflow if the mass transfer efficiency is higher than 60% • Allows the “double degenerate merger” Nino Panagia Radio Supernovae
Core-collapse Supernovae Nino Panagia Radio Supernovae
Type IIL Supernovae Nino Panagia Radio Supernovae
Optical Radio Type IIL Optical/Radio SN1979C My FIRST supernova!!! Nino Panagia Radio Supernovae
SN 1979C: The First 10 Years A periodic modulation? 20 cm 6 cm Nino Panagia Radio Supernovae
SN 1979C: A Sinusoidal Fit Spiral pattern expected for a binary system including 15 and 10 M stars that are orbiting around each other with a period of ~5000 days A wide binary system Nino Panagia Radio Supernovae
SN1979C: Twenty Years of Observations About 20,000 years before exploding the progenitor ejected a discrete shell? Pulsational instability? Panagia & Bono 2001 An increase of CSM density Nino Panagia Radio Supernovae
Type IIL SN1980K - Radio An decrease of CSM density (/2) Nino Panagia Radio Supernovae
Pre-SN Evolution of Massive Stars[Bono & Panagia 2001, and in prep.] Hydrostatic Evolution + Pulsational Instabilities Nino Panagia Radio Supernovae
Type IIn Supernovae Nino Panagia Radio Supernovae
Type IIn SN 1986Jone of the brightest RSNe Nino Panagia Radio Supernovae
SN 1986J The gradual rise implies a clumpy absorbing medium Nino Panagia Radio Supernovae
SN1986J (1999 VLBI obs.) And clumpy it is… Nino Panagia Radio Supernovae
SN 1987A orThe unusual explosion ofa normal Type II supernova[~18M progenitor] Nino Panagia Radio Supernovae
SN1987A – Optical [Type II pec] Nino Panagia Radio Supernovae
SN 1987A – Radio Ring Nino Panagia Radio Supernovae
10 years after explosion the ring started lighting up… 1996 More than 20 spots now seen to brighten, due to the collision of the ejecta with the central ring. Over the next decades, as the entire ring will light up, the Evolutionary history of the star’s mass loss will be revealed 2006 Nino Panagia Radio Supernovae
SN 1987A Radio Evolution Late Evolution - Gradual Rise - High Luminosity High density medium Early Evolution: - Fast rise - Low luminosity Low density CSM Nino Panagia Radio Supernovae
Optical, X-ray, & Radio light curves of SN1987A ring 1990 1995 2000 2005 The fireworks have started! optical radio X-ray Nino Panagia Radio Supernovae
Type IIb Supernovae Nino Panagia Radio Supernovae
Type IIb SN 1993J in M81 (NGC 3031) Nino Panagia Radio Supernovae
SN 1993J: Radio Observations[Type IIb] Nino Panagia Radio Supernovae
Circumstellar Interaction SN shock wave with the pre-SN dense wind [Chevalier & Fransson 1994; Fransson, Lundqvist, & Chevalier 1996] ~109 K (adiabatic) Strong X-ray emission expected ~107 K (radiative) <104 K (cool shell) Nino Panagia Radio Supernovae
SN 1993J – Radio Light Curves(only SSA= synchrotron self-absorption) Nino Panagia Radio Supernovae
SN 1993J – Spectral Index Evolution(SSA only) Nino Panagia Radio Supernovae
SN 1993J – Brightness Temperature(SSA only) Nino Panagia Radio Supernovae
SN 1993J – Radio Light Curves(only FFA=free-free absorption ) Nino Panagia Radio Supernovae
SN 1993J – Spectral Index Evolution(FFA only) Nino Panagia Radio Supernovae
SN 1993J – Brightness Temperature(FFA only) Nino Panagia Radio Supernovae
SN 1993J – Radio Light Curves(SSA + FFA) Nino Panagia Radio Supernovae
SN 1993J – Spectral Index Evolution(SSA + FFA) Nino Panagia Radio Supernovae
SN 1993J – Brightness Temperature(SSA + FFA) Nino Panagia Radio Supernovae
SN 1993J – Late (>day3100) Evolution(negligible SSA & FFA) Nino Panagia Radio Supernovae
Expansion of SN 1993J from age 5 months to age 31 months [Marcaide et al. 2000, 2007] SN1993J: VLBI Observations Nino Panagia Radio Supernovae