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Claes Fransson, Stockholm University Collaborators: R. Chevalier (UVa), Poonam Chandra (UVa) P. Gröningsson, C. Kozma, P. & N. Lundqvist, T. Nymark (SU), B. Leibundgut, J. Spyromilio, K. Kjaer, R. Kotak (ESO) Shocks in SN 1987A
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SAINTS collab. SN 1987A ring collision
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Chandra & ATCA Park et al Manchester et al
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Dust emission Bouchet et al 2006 T ~ 166 K Si feature collisionally heated Spitzer Gemini S + Spitzer 11.7 18.3
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Gröningsson et al 2006 VLT/UVES FWHM ~ 6 km s -1 Seeing 0.5-0.8” Resolves N/S
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Gröningsson et al 2006 HH narrow [O III] 5007 Narrow FWHM ~ 10 km s -1 from unshocked ring Broad V max 300-400 km s -1 from shocked ring (Pun et al 2002) broad He I
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Gröningsson et al (2006) Smith et al (2006), Heng et al (2006) Velocity (10 4 km/s) Reverse shock Broad ~16,000 km/s emission from reverse shock going back into ejecta VLT/FORS Dec 2006 2002 2000
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Reverse shock evolution HH Ca II
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Broad ~16,000 km/s emission from reverse shock going back into ejecta 1. Ly and H from charge exchange of neutral ejecta? Probably not (Heng & McCray 2007) 2. X-ray excitation by reverse shock + blobs more likely? Recombination time in ejecta long, non-thermal excitation, …. non-spherical Similar to freeze-out phase for radioactive excitation and to Type IIb/IIn CS interaction (cf SN 1993J) 3. Cosmic ray excitation? What is causing the reverse shock emission?
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Intermediate velocity lines from shocked ring protrusions Gröningsson et al 2006 Oct 2002 N part of ring ~ ‘Spot 1’. Peak velocity ~ 120 km s -1. Max extension ~ 300 km s -1
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VLT/SINFONI March 2005 He I 2.06 Kjaer et al 2007 Adaptive optics integral field unit for J, H, K Expansion velocities along ring J-band
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Average velocity over the ring ~ 120 km s -1 UVES gives high and low velocity tails Deprojected velocities
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VLT/UVES spectrum Max. velocity ~ shock velocity ~ 300-400 km/s Coronal lines Gröningsson et al 2006 Fe XIV 5303 T s ~ 2x10 6 K H , He I, N II, O I-III, Fe II, Ne III-V….. Cooling, photoionized gas behind radiative shock into ring protrusions
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Borkowski et al 1997 Pun et al 2002 Hydrodynamics of ring collision Optical emission from radiative shocks into the ring material Radio and hard X-rays from reverse shock
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shock Radiative shock structure Post-shock densities ~5x10 6 - 10 7 cm -3. Agrees with nebular diagnostics photoion. precursor narrow Ha, [N II], [O III] coll. ioniz. X-rays Coronal lines photoion. broad H , [OIII],… V s = 350 km/s n o = 10 4 cm -3
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Shock velocity into hot-spots 300 – 400 km s -1 T s ~ 2x10 6 K Coronal lines complement the X-rays to probe whole temp. range Shock velocity Coronal line diagnostics Gröningsson, Nymark…
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VLT/ISAAC Near-IR [Fe XIII] 1.0747-1.0798
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Chandra: Zhekov et al (2005, 2006) also XMM by Haberl et al X-rays N VII, O VII-VIII, Ne IX-X, Mg XI-XII, Si XIII, Fe XVII….. Two components: High density (10 4 cm -3 ) kT ~ 0.5 keV + Low density (10 2 cm -3 ) kT ~ 3.0 keV
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Optical/UV from radiative shocks Soft X-rays from radiative + adiabatic shocked ring blobs Hard X-rays and radio from adiabatic reverse shock A radiative shock gives X-rays, UV, optical, IR Expect correlation between optical/UV and soft X-rays, but not with hard and radio
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Time evolution Coronal lines and soft X-rays correlate. Soft X-rays from hot-spots. Hard from reverse shock & blast wave Optical: Gröningsson et al X-rays: Park et al 2005
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Gröningsson et al 2007 Oct 2002 Low ionization lines (up to [O III]) have V max ~ 250 km s -1 Coronal lines V max ~ 400 km s -1 Highest vel. shocks may have been adiabatic in 2002
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Line widths of low ionization ions increase with time 2000: ~ 250 km s -1 -> 2006: ~ 450 km s -1. Coronal lines ~ constant ~ 450 km s -1 Cooling shocks
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yrs High velocity shocks seen in soft X-rays gradually become radiative Now, H up to ~ 450 km s -1 n e up to ~ 4x10 4 cm -3 ~ ring density (Lundqvist & CF 96) Expect this to continue to higher shock velocities
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Narrow, unshocked lines Unshocked ring ionized by SN shock breakout, then recombining Ring is now ionized by X-rays from shocks. Come-back of narrow lines Pre-ionized region ~ 5x10 17 (n/10 4 cm -3 ) -1 cm Shock models: Most of absorbed X-rays in pre-shock gas are re-emitted as [O III] We are now starting to see the re-ionization of the ring!
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Conclusions SN 1987A excellent case of CSI, with both thermal and non-thermal processes. Line profiles probe shock distribution + dynamics UV/optical/IR from radiative shocks Strong correlation between increase in optical and soft X-rays Coronal lines complement soft X-rays as shock diagnostics Higher velocity shocks gradually cooling. Now up to ~ 450 km s -1 Unshocked CSM is now becoming ionized. Bright future!
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Relation to other mass losing SNe
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1. ej >> CSM Type IIL, IIb SN 1993J, SN 1979C Steady wind Line width ~ V ej 2. ej << CSM Type IIn… SN 1995N, SN 1998S Blobs, rings, short-lived superwinds… SN 1987A Line width ~ V blast << V ej Two cases for the line widths
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SN 1993J optical Filippenko et al 1994 Fransson et al 2004 Box-like line profiles narrow emitting shell Transition from Type II to Type Ib = Type IIb HH He I
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Cool shell behind rev. shock SN ejecta partially ionized, T<7000K fully ionized neutral, T ~ (1-3)x10 4 K n ~ 10 10 cm -3 n ~ 10 6 – 10 7 cm -3 H , Mg II, Fe II O III-IV, N III-V, Ne III-V UV & optical line emission
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SN 1993J optical/UV Good fit with ionized ejecta (O III etc) + cool, dense shell (H , Mg II, Fe II) Consistency of X-ray flux and UV/optical flux HST (SINS) + Keck HH He I Mg II [O III]
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Type IIn SNe SN 1995N (Fransson et al 2004) Broad H-lines(5-10,000 km/s)+ narrow (< 500 km/s) lines. HI, He, O III, Ne III-V, Fe II-VII Sometimes intermediate (few x 1000 km/s) metal lines Broad (eg H ) 15,000 km/s may at be due to multiple electron scattering of narrow H emission by CS gas (Chugai 2001) Light curve often dominated by CSI even at early times
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SN 1995N (Fransson et al 2004) Spectral modeling: N/C large + enhanced O close to reverse shock most of the envelope lost before the explosion dM/dt ~ 10 -4 -10 -3 M O yr -1 Late superwind phase? (Heger et al 1997 ) Binary ejection? May be connection to Ibcs (cf Chugai & Chevalier 2006) Progenitor of SN 2005gl possibly identified as an LBV star (if not a cluster) (Gal-Yam et al 2006)
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SN 1979C (IIL), 1987A (IIP), 1993J (IIb), 1995N (IIn), 1998S (IIn) all have N/C >> 1 (Fransson et al 1984, 1989, 2001, 2005) SN 1998S IIn N/C ~ 6 SN 1995N IIn N/C ~ 4 SN 1993J IIb N/C ~ 12 SN 1987A IIP N/C ~ 5 SN 1979C IIL N/C ~ 8 Solar N/C ~ 0.25 All indicate CNO processing and mass loss and/or mixing SN 1998S CNO diagnostics
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N/C >> 1 CNO burning heavy mass loss + mixing Rotation helps! Roche lobe overflow N/C strong fcn of mass loss 40 M at ZAMS Meynet & Maeder 2003 SN 1993J binary model Woosley et al 1994
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X-ray spectra useful probes of the ejecta composition solarhelium zone carbon zone oxygen zone Nymark et al 2006
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Nymark, Chandra, CF 2007 data: XMM Zimmermann & Aschenbach Chandra: Swartz et al 2003 SN 1993J CNO enriched H or He envelope
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Data: Pooley et al 2002 Modeling: T. Nymark, P. Chandra, CF 2007 SN 1998S CNO enriched H envelope
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Conclusions SN 1987A excellent case of CSI, with both thermal and non-thermal processes. Soft X-rays and UV/optical/IR from radiative shocks Line profiles probe shock distribution + dynamics Correlation between increase in optical and soft X-rays Coronal lines probe shocks with 300-400 km s -1 Higher velocity shocks become radiative. Now up to ~ 450 km s -1 Unshocked ring is now becoming ionized. CS interaction has different signatures depending on CSM structure. Physics similar CNO processing seen in most SNe with strong mass loss. X-rays important probe of ejecta composition for all CC SNe
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Gröningsson et al (2006) Smith et al (2006), Heng et al (2006) Velocity (10 4 km/s) Reverse shock Broad ~16,000 km/s emission from reverse shock going back into ejecta Ly and H from charge exchange of neutral ejecta (??) (Heng & McCray 2007) X-ray excitation by reverse shock + blobs likely. Time evol. may tell. VLT/FORS Dec 2006 2002 2000
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VLT/SINFONI Kjaer et al 2007
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Chandra & ATCA Park et al Manchester et al Bouchet et al 2006 Gemini S + Spitzer 11.7 18.3
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shock Optical lines probe different temperature intervals in the cooling gas behind the radiative shocks TeTe Fe
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VLT/SINFONI March 2005 He I 2.06 Pa Br [Fe II] Kjaer et al 2007 Adaptive optics integral field unit for J, H, K Expansion velocities along ring J-band
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P. Challis/ SAINTS collab. SN 1987A ring collision
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Reverse CD Blast wave ejecta CSM VsVs V rev 1.If ej >> CSM V s >> V rev Type IIL, IIb SN 1993J, SN 1979C 2. ej << CSM V s << V rev Type IIn SN 1995N, SN 1998S SN 1987A 1. Steady wind 2. Blobs, rings, superwinds… Two cases for the mass loss
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SN 1987A radioactivities M( 56 Ni) = 0.07 M O, M( 57 Ni) = 3x10 -3 M O, M( 44 Ti) = 1x10 -4 M O Energy stored as ionization, later released as recombination flattening of light curve
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44 Ti mass M( 44 Ti) = 1 x10 -4 M O Range (1-2) x10 -4 M O IR photometry needed M( 44 Ti) = (0.5, 1, 2) x10 -4 M O
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Line fluxes: H Excellent fit! But, hydrogen lines dominated by freeze out in envelope H not sensitive to M( 44 Ti)
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0.5-2 keV 3-10 keV + radio 3 -20 cm Radio and X-ray brightening Correlation of hard X-rays and radio probably close to reverse shock Park et al 2005 Manchester et al
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Gröningsson et al (2006) Smith et al (2006), Heng et al (2006) Velocity (10 4 km/s) Reverse shock HH Broad ~15,000 km/s emission from reverse shock going back into ejecta Ly and H from charge exchange of neutral ejecta (?) (Michael et al 2003) 44 Ti reverse shock VLT/UVES 2002 2000
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Conclusions Mass loss dominant factor for radio, X-rays and late optical Increasingly important for IIP IIL IIn,p Ib/c. N/C important diagnostic Strong evidence for magnetic field amplification (and particle acceleration). In SN 1993J B-field close to equipartition. Electrons far below. Effects of cosmic rays? SN 1987A excellent shock lab. to study both thermal and non-thermal processes. Expect collision with main ring to start soon.
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Mass loss rates Type IIP dM/dt 10 -6 M O yr -1 (for u = 10 km s -1 ). RSG wind OK Type IIL dM/dt 2x10 -5 – few x 10 -4 M O yr -1 (for u = 10 km s -1 ). 'super wind' (Heger et al) t = V s /u t obs 5x10 2 t obs > 10 4 / (u/10 km s -1 ) yrs i.e., several M O lost Type IIn dM/dt 10 -4 -10 -3 M O yr -1 (for u = 10 km s -1 ). super wind Clumping (Chugai) ? Asymmetric wind (Blondin, Chevalier, Lundqvist) ? Type Ib/c dM/dt 10 -7 - 10 -5 M O yr -1 (for u = 1000 km s -1 ). Mass loss rate uncertain
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SN 1993J Radio: Synchrotron spectrum Wavelength dependent turn-on of emission VLBI imaging of SN 1993J and SN 1986J Van Dyk et al 1994, Weiler, Panagia, Sramek 2002 Bartel et al Marcaide et al. 1.3 cm 21 cm Log t (days) Log S
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Chevalier (1982) CF (1984) Chevalier & CF (1994)
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SN 1993J X-rays ROSAT 0.1 - 2.4 keV ( Zimmermann et al 1994, Immler et al 2002) ASCA 1 – 10 keV ( Uno et al 2002) COMPTON-GRO/OSSE 50 – 200 keV (Leising et al 1994) Chandra (Swartz et al 2002) XMM/Newton (Zimmermann & Aschenbach 2003)) t < 50 days kT ~ 100 keV L x 5x10 40 erg/s 50 - 200 keV 2x10 39 erg/s 0.1 - 2.4 keV t > 200 days kT ~ 1 keV L x 1x10 39 erg/s 0.1 - 2.4 keV Transition from hard to soft spectrum! Zimmermann & Aschenbach 2003 Temperature (keV) Days after explosion
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X-ray evolution At 10 days: Only X-rays from outer, CS shock T~10 9 K At 200 days: X-rays from reverse shock dominates T~10 7 K CF, Lundqvist & Chevalier 1996 Hard to soft evolution natural consequence of the cool shell
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Fassia et al 2001 SN 1998S Narrow CS lines have V ~ 40-50 km/s
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Radiative reverse shock spectra RS radiative for One-temperature spectrum bad approx. for cooling shock. Affects abundance estimates by large factor! T. Nymark, CF, C. Kozma 2006 O VIII C VI Fe XVIII-XXIII Si XIII S XV Mg XI-XII TeTe Distance from shock
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Origin of the rings R ~ 10 18 cm, V exp ~10 km s -1 t dyn ~2x10 4 years N/C ~ 5 Origin (?): Merger inducing the equatorial mass loss and outer rings (Podziadlowski 1992, Heger & Langer 1998, Morris & Podziadlowski 2005) Can this happen in a Ic progenitor? Late SN2001em emission (Chugai & Chevalier 2006)
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Type IIP (little mass lost) IIL, IIn, IIb ( < 0.5 M of H envelope) Ib (only He core) Ic (only O core) Effects of binary mass loss probably important SN Types determined by mass loss
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SN 1993J in M 81 3.6 Mpc Best studied CS case: SN 1993J
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RADIO I. Free-free absorption by the CSM T wind ~ 10 5 K (Lundqvist & CF 1989) Good fit to Type IIL SNe (SN 1979C, 1980K…..) SN 1979C IIL dM/dt = 5x10 -5 – 10 -4 M O /yr for u=10 km/s superwind phase? Montes et al 2000
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Inverse Compton scattering by photospheric photons suppresses radio at optical max. B << e indicated by flat light curve (?) degeneracy between B and e Typical for galactic RSG mass loss rates SN 2004et Obs: Stockdale (2004), Beswick et al (2004), Argo et al (2005) Type IIP (Chevalier, CF, Nymark 2006) Most common core collapse SN
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II. Synchrotron self-absorption Absorption by same rel. electrons as are emitting Note: Expansion velocity, i.e. radius, from line profiles or VLBI, not a parameter, c.f. GRB’s Log Log F = 1
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VLBI Bartel et al 2001 Size of radio emitting region Line widths (1.0-1.5)x10 4 km s -1 HST, SINS
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Questions Importance of shells. How common is e.g. the SN 1987A ring? Effects of binarity. Mergers, non-spherical effects (e.g., Podziadlowski 1992). Similarities with WR stars in binaries? Acceleration mechanism of non-th. particles??? Collissionless shock thermalization Effects of cosmic rays on shock structure and non-thermal spectrum (e.g., SNRs)
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Dust condensation in cool shell? T too high in H & He zones, unless density very high. OK in O/C or O/Si regions Temperature sensitive to ejecta composition See also Deneult, Clayton & Heger 2003
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Dust extinction first in UV, later in H CF et al 2005 H L Mg II SN 1998S dust extinction
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Dust in SNe AGB stars and SNe main sources for dust Little direct evidence for dust condensation in SNe! I. Ejecta condensation SN 1987A at ~ 500 days from line profiles, far-IR emission (Bouchet, Danziger &Lucy 1992) Cas A. ISO mid-IR emission (Lagage et al 1996, Douvion et al 2001) Cas A
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Progenitors: Mass loss determines SN Type. Type IIP (little mass lost),....IIn, IIb ( < 0.5 M of H envelope), Ib (only He core), Ic (only O core) Ejecta structure: Shock dynamics probes density structure of SN ejecta Shock physics: Thermal radiation processes (X-rays) Non-thermal radiation processes (radio/X-rays) Relativistic particle acceleration Dust production SN – GRB connection: GRB afterglow determined by circumstellar environment of the SN. Connection ty Type Ic SNe Why is circumstellar interaction of SNe important?
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Core collapse SNe Type II H, He lines. H, He, O, Mg, Ca…. Type Ib No H. No Si II. He, O, Mg, Ca Type Ic No H, He. No Si II. O, Mg, Ca Filippenko 1997
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(Filippenko 1997) II: IIP (plateau) most common. M V ~ -16- -17. 10-15 M RSG IIL (linear), IIn (narrow) 8-10, 15-20 M (??), binaries ? Ib/c M V -17 - -20. WR stars > 25 M , some binaries ?
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Dust emission in Type IIs Gerardy et al 2002 All Type IIn or IIL
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Dust temperatures and luminosity Gerardy et al 2002 T dust ~ 800-1300 K ~ condensation temperature L IR + T dust Dust condensation at V ~ 4000 km/s at ~ 300 days (Pozzo et al 2004) Not in SN core! Close to reverse shock Pozzo et al 2004 Velocity (1000 km/s)
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Where ? 1. Ejecta (SN 1987A). 1. Heated dust 1. Echo 1. Dust formation in cool dense shell
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Cold dust in Cas A at 850 Dust emission between reverse and forward shocks SCUBA Dunne et al 2003 Dust in Cas A Dust + synchroDust only
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SN 1995N Reverse shock close to the O core HST/Keck/VLT CF et al 2002 H velocity ~ 10,000 km/s [O III] velocity ~ 4,000 km/s Narrow lines ~ 500 km/s Shock not sph. symm. ?
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Dust condensation Grain comp region T cond GraphiteC-O1900 Al 2 O 3 O-zone1600 Mg Si O 3 O-zone1500 Fe 3 O 4 ?1300 SiO 2 O/Si1500 Kozasa et al 1990 Need temperature less than 2000 K
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C-O shock structure T 10 10 cm -3 behind reverse shock. OK for dust condensation shock Dust?
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Progenitors: Mass loss determines SN Type. Type IIP (little mass lost),....IIn, IIb ( < 0.5 M of H envelope), Ib (only He core), Ic (only O core) Ejecta structure: Shock dynamics probes density structure of SN ejecta Shock physics: Thermal radiation processes (X-rays) Non-thermal radiation processes (radio) Relativistic particle acceleration Dust production SN – GRB connection: GRB afterglow determined by circumstellar environment of the SN. Why is circumstellar interaction of SNe important?
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Conclusions 1. Consistent picture of radio, X-rays and optical/UV observations based on CS interaction 2. Combination of radio, X-rays and optical/UV observations provide reliable mass loss rates for progenitors 3. Cool, dense shell crucial for X-ray evol., X-ray to optical/UV reprocessing, line formation…. 4. Radio observations provide an excellent laboratory for understanding non-thermal particle acceleration and collisionless shock physics 5. CNO processing seen in most SNe 6. Dust may form in the cool, dense shell 7. Stellar wind bubbles compressed by ISM pressure in starbursts to pc dimensions may explain constant density and high pressure inferred from GRB afterglows
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SN 1995N Reverse shock close to the O core
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SN 1995N Reverse shock close to the O core HST/Keck/VLT CF et al 2002 H velocity ~ 10,000 km/s [O III] velocity ~ 4,000 km/s Narrow lines ~ 500 km/s Shock not sph. symm. ?
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N/C >> 1 CNO burning heavy mass loss + mixing N/C increases with mass loss Meynet & Maeder 2003 40 M at ZAMS
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Mass loss processes I. Single stars Blue SGs u ~ 500 – 3000 km/s dM/dt 10 -7 – 10 -5 M O /yr Red SGs u ~ 10 – 50 km/s dM/dt 10 -6 – 10 -4 M O /yr Superwinds (cf. AGB's): Heger et al (1997) find large amplitude pulsations with several M O per 10,000 years dM/dt ~ 10 -4 M O /yr II Binaries Winds RL overflow, common envelope phases....
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X-rays Thermal X-rays dominated by reverse shock Reverse shock radiative! Cooling shock. One-temp. fits misleading! Cool, dense shell between reverse shock and forward shock absorption of X-rays
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Conclusions from CNO Progenitors must have lost most of the hydrogen envelope before explosion Confirms mass loss as the important factor for the SN Type among core collapse SNe
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Absorption by cool dense shell
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RADIO I. Free-free absorption by the CSM T wind ~ 10 5 K (Lundqvist & CF 1989) Good fit to Type IIL SNe (SN 1979C, 1980K…..) dM/dt = 5x10 -5 – 10 -4 M O /yr for u=10 km/s
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II. Synchrotron self-absorption Absorption by same rel. electrons as are emitting
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Obs: VLA: van Dyk et al 1994, Weiler, Panagia, Sramek 2002 CF & Björnsson 1998 Model and VLA light curves csm r -2 OK!! No evidence for mass loss variations or s 2. 2. dM/dt = 5x10 -5 M O /yr for u=10 km/s, same as from X-rays 3. Injection spectrum n rel -2.1. Synchrotron cooling steepens this! 4. B 0.15 e 10 -4 Assume: U B U therm, U rel U therm Self-consistent calculation of rel. electron spectrum, including all cooling processes, as well as radiative transfer
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Strong interactors = strong radio, X-ray, optical emission high mass loss rates Type IIL, IIn, IIp.. radiative reverse shocks Weakly interacting Type IIP adiabatic reverse shocks Transitions: SN 1987A weak strong CSI observed for all types of core collapse SNe
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H profile in SN 1998S Fransson et al 2004 Double peaked H profile implies thin shell If R/R < v th /V exp ~10 -3 Sobolev not valid. Optically thick lines F M-shaped profiles Confirms line formation in cold, dense shell R < 10 13 cm. Consistent with photoionization models see also Leonard et al 2000 Gerardy et al 2000 Poozo et al 2004
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X-rays from Type IIP SN 1999em, SN 1999gi, SN 2004dj, …….. L x ~ (1-5)x10 38 erg/s (0.5-8 keV) 1. Inverse Compton from relativistic electrons at blast wave 2. Thermal dominated by adiabatic reverse shock Little spectral info we can not discriminate between 1 & 2 IC would constrain B and e (c.f., 2002ap) Pooley & Lewin, Schlegel et al
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Spectrum of relativistic particles Type Ic SNe: Radio has ~ 1 p ~ 3 Cooling not very important Acceleration spectrum steeper than ‘standard’ Fermi case? dN/dE E -p F = (p-1)/2 First order Fermi acceleration across shock p = (r+2)/(r-1) ordinary strong shock r=4 p = 2 = 0.5 Synchrotron or Compton cooling p -> p+1 = 3 = 1.0
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Whish list More radio spectra and light curves like SN 1993J (including low frequencies). Optical line widths (or VLBI!) crucial for analysis Very late radio and X-ray obs. (e.g. SN 1979C, 1980K, 1993J, 2001em, 2003L….). Follow reverse shock back into processed parts of ejecta. Probe wind bubble structure UV + X-ray obs. for abundances Deeper X-ray obs. of esp. IIP and Ib/c to discriminate between IC and thermal.
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Conclusions 1. Consistent picture of radio, X-rays and optical/UV observations based on CS interaction 2. Combination of radio, X-rays and optical/UV observations provide reliable mass loss rates for progenitors 3. Cool, dense shell crucial for X-ray evol., X-ray to optical/UV reprocessing, line formation…. 4. Radio observations provide an excellent laboratory for understanding non-thermal particle acceleration and collisionless shock physics 5. CNO processing seen in most SNe 6. Dust may form in the cool, dense shell 7. Stellar wind bubbles compressed by ISM pressure in starbursts to pc dimensions may explain constant density and high pressure inferred from GRB afterglows
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SN classification Type Ia Early: No H, He. Si II 6150 line. Late: Fe II-III Type II H, He lines. H, He, O, Mg, Ca…. Type Ib/c No H, He (Ic). No Si II. O, Mg, Ca Filippenko 1997
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(Filippenko 1997) Ia : Standard candles (almost!). Thermonuclear explosions of 1.4 M white dwarf Core collapse II: IIP (plateau) most common. M V ~ -16- -17. 10-15 M RSG IIL (linear), IIn (narrow) 8-10, 15-20 M (??), binaries ? Ib/c M V -17 - -20. WR stars > 25 M , some binaries ?
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IIn Narrow line SNe (Filippenko 1997) Flat, very bright light curves
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Good fit with SSA. Inverse Compton cooling by photospheric photons important. L Bol peaks at ~ 10 days Berger, Kulkarni, Chevalier 2002 Björnsson & CF 2003 Type Ic SN 2002ap Can only determine from SSA alone
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Borkowski et al 1997
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SN 1993J X-rays XMM: Zimmermann & Aschenbach 2003 Chandra: Swartz et al 2003 Thermal kT ~ 0.34 + 6.5 keV Enhanced Si (?) (Swartz et al) Can NOT use a one (or two) temperature components. Cooling reverse shock + shell absorption + forward shock
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SN 1993J SSA + free-free SSA only dM/dt = 5x10 -5 M O /yr for u=10 km/s Fit to each epoch + radius B(t) & N(t) CF & Björnsson 1998
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Magnetic field and rel. particle density 1. Wind B-field 1-2 mG at 10 16 cm (Cohen et al 1987) Amplification of B-field behind shock. Weibel instab.? (Medvedev & Loeb 1999) 2. U B 0.15 U therm i.e. B 0.15 e 10 -4 3. U e 10 -4 U therm log R log B log n e Note : If n e ( ) ~ n p ( ), then p ~ m p /m e e ~ 0.2 ??
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Obs: VLA: van Dyk et al 1994, Weiler, Panagia, Sramek 2002 CF & Björnsson 1998 Model and VLA light curves Assume B and e constant Self-consistent calculation of rel. electron spectrum, including all cooling processes, as well as radiative transfer Synchrotron cooling gives Cooling break observed with GMRT and VLA at ~3400 days close to predicted (Chandra et al 2004)
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Weiler et al, KITP 2006 Type Ic SNe GRB connection SN 1994I in M 51 ‘best case’ Steep light curves F t -1.2
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Spectra well fitted by SSA Steep radio spectra F ~ 1
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B t -1 as expected for equipartition in wind B ~ 0.1
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Chevalier 1998 SSA FF Free-free vs synchrotron self-absorption High & low V F-F; Low & high V SSA
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Non-thermal, inverse Compton scattering of photospheric photons Obs: XMM: Sutaria et al 2003, Pian et al 2003 VLA: Berger et al 2002 2002ap: X-rays from inverse Compton 1. If 2. If Low for WR star! day 6 (Björnsson & CF 2003)
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Late time X-ray emission from Type Ic SNe SN 1994I at 7 years Chandra Immler et al 2002 Thermal? Too low density in a WR wind! Inverse Compton? No photospheric photons from radioactivity Synchrotron? Too low if extrapolated from X-rays
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Spectrum of relativistic particles dN/dE E -p p = (r+2)/(r-1) F = (p-1)/2 First order Fermi acceleration across shock p = (r+2)/(r-1) ordinary strong shock r = 4 p = 2 = 0.5 Radiative cooling p -> p+1 = 3 = 1.0 Type Ic SNe: Radio has ~ 1 p ~ 3 Cooling not very important Acceleration spectrum steeper than ‘standard’ Fermi case?
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Cosmic ray dominated shocks CR pressure ~ 4/3 and particle loss high compression r ~ 10 (instead of r ~ 4) flattening of spectrum at high energy steepening at low F = (p-1)/2 dN/dE E -p p = (r+2)/(r-1) Berezko & Ellison 2001 1 10 3 10 7 E ~ m p E 2 dN/dE radio X-rays
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Radio: Steepening of spectrum. LC not much affected X-rays: Strongly dependent on slope of rel. electron spectrum. Explains high X-ray flux at late epochs Cosmic ray modified shock spectra and light curves Chevalier + CF 2006 X-rays radio IC CR mod. synchro ‘stand.’ synchro IC synchro
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Results from synchrotron modeling 1. Excellent laboratories for rel. particle acceleration 2. csm r -2 OK!! No evidence for mass loss variations or s 2. 3. Injection spectrum n e -2.1 in SN 1993J. 4. B 0.15 e 10 -4. (Note : If n e ( ) ~ n p ( ), then p ~ m p /m e e ~ 0.2 ?? ) 5. Compton cooling by photospheric photons important for first ~ 50 days. Synchrotron for years 6. Evidence for cosmic ray dominated shocks for Type Ic SNe
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Shock structure Chevalier & Blondin 1995 Fransson et al 1996 CS shock adiabatic Reverse shock radiative TiTi TeTe
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Conclusions Mass loss dominant factor for radio, X-rays and late optical Radio, X-rays and optical/UV provide reliable mass loss rates for progenitors. Increasingly important for IIP IIL IIn,b Ib/c. Consistent with the Type II taxonomy. CNO processing seen in most SNe. Dust may form in reverse shock Strong evidence for magnetic field amplification (and particle acceleration). In SN 1993J and SN 1994I B-field close to equipartition. Electrons far below. Late X-ray emission may indicate cosmic ray acceleration SN 1987A excellent case of CSI, with both thermal and non-thermal processes. Expect most of the ring to be ionized by the X-rays and the collision with the main ring to start soon.
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