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Shocks in SN 1987A. Claes Fransson, Stockholm University Collaborators : R. Chevalier (UVa), Poonam Chandra (UVa) P. Gröningsson, C. Kozma, P. & N. Lundqvist, T. Nymark (SU),
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Shocks in SN 1987A 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)
SN 1987A ring collision SAINTS collab.
Chandra & ATCA Park et al Manchester et al
Dust emission Gemini S + Spitzer Bouchet et al 2006 Spitzer 11.7 18.3 T ~ 166 K Si feature collisionally heated
VLT/UVES FWHM ~ 6 km s-1 Seeing 0.5-0.8” Resolves N/S Gröningsson et al 2006
Gröningsson et al 2006 [O III] 5007 Ha narrow broad He I Narrow FWHM ~ 10 km s-1 from unshocked ring Broad Vmax 300-400 km s-1 from shocked ring (Pun et al 2002)
Reverse shock Gröningsson et al (2006) Smith et al (2006), Heng et al (2006) VLT/FORS Dec 2006 2002 2000 Velocity (104 km/s) Broad ~16,000 km/s emission from reverse shock going back into ejecta
Reverse shock evolution Ha Ca II
What is causing the reverse shock emission? 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?
Intermediate velocity lines from shocked ring protrusions Oct 2002 Gröningsson et al 2006 N part of ring ~ ‘Spot 1’. Peak velocity ~ 120 km s-1. Max extension ~ 300 km s-1
VLT/SINFONI March 2005 He I 2.06 Adaptive optics integral field unit for J, H, K Kjaer et al 2007 J-band Expansion velocities along ring
Deprojected velocities Average velocity over the ring ~ 120 km s-1 UVES gives high and low velocity tails
Gröningsson et al 2006 Coronal lines VLT/UVES spectrum Max. velocity ~ shock velocity ~ 300-400 km/s Fe XIV 5303 Ts ~ 2x106 K H, He I, N II, O I-III, Fe II, Ne III-V….. Cooling, photoionized gas behind radiative shock into ring protrusions
Hydrodynamics of ring collision Optical emission from radiative shocks into the ring material Radio and hard X-rays from reverse shock Borkowski et al 1997 Pun et al 2002
Radiative shock structure Vs = 350 km/s no = 104 cm-3 shock photoion. broad H, [OIII],… photoion. precursor narrow Ha, [N II], [O III] coll. ioniz. X-rays Coronal lines Post-shock densities ~5x106 - 107 cm-3. Agrees with nebular diagnostics
Coronal line diagnostics Gröningsson, Nymark… Shock velocity Shock velocity into hot-spots 300 – 400 km s-1 Ts ~ 2x106 K Coronal lines complement the X-rays to probe whole temp. range
Near-IR VLT/ISAAC [Fe XIII] 1.0747-1.0798
X-rays Chandra: Zhekov et al (2005, 2006) also XMM by Haberl et al N VII, O VII-VIII, Ne IX-X, Mg XI-XII, Si XIII, Fe XVII….. Two components: High density (104 cm-3) kT ~ 0.5 keV + Low density (102 cm-3) kT ~ 3.0 keV
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
Time evolution Optical: Gröningsson et al X-rays: Park et al 2005 Coronal lines and soft X-rays correlate. Soft X-rays from hot-spots. Hard from reverse shock & blast wave
Gröningsson et al 2007 Oct 2002 Low ionization lines (up to [O III]) have Vmax ~ 250 km s-1 Coronal lines Vmax ~ 400 km s-1 Highest vel. shocks may have been adiabatic in 2002
Cooling shocks 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 yrs High velocity shocks seen in soft X-rays gradually become radiative Now, H up to ~ 450 km s-1 ne up to ~ 4x104 cm-3 ~ ring density (Lundqvist & CF 96) Expect this to continue to higher shock velocities
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 ~ 5x1017 (n/104 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!
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. • Brightfuture!
Two cases for the line widths 1. ej >> CSMType IIL, IIb SN 1993J, SN 1979C Steady wind Line width ~ Vej 2.ej << CSMType IIn… SN 1995N, SN 1998S Blobs, rings, short-lived superwinds… SN 1987A Line width ~ Vblast << Vej
SN 1993J optical H Filippenko et al 1994 Fransson et al 2004 He I Transition from Type II to Type Ib = Type IIb Box-like line profiles narrow emitting shell
UV & optical line emission Cool shell behind rev. shock SN ejecta partially ionized, T<7000K fully ionized neutral, T ~ (1-3)x104 K n ~ 1010 cm-3 n ~ 106 – 107 cm-3 H, Mg II, Fe II O III-IV, N III-V, Ne III-V
SN 1993J optical/UV HST (SINS) + Keck Mg II He I H [O III] 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
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
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 ~ 10-4-10-3MO 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)
CNO diagnostics 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 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
N/C strong fcn of mass loss 40 M at ZAMS Meynet & Maeder 2003 N/C >> 1 CNO burning heavy mass loss + mixing Rotation helps! Roche lobe overflow SN 1993J binary model Woosley et al 1994
X-ray spectra useful probes of the ejecta composition solar helium zone Nymark et al 2006 oxygen zone carbon zone
SN 1993J Nymark, Chandra, CF 2007 data: XMM Zimmermann & Aschenbach Chandra: Swartz et al 2003 CNO enriched H or He envelope
SN 1998S Data: Pooley et al 2002 Modeling: T. Nymark, P. Chandra, CF 2007 CNO enriched H envelope
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
Reverse shock Gröningsson et al (2006) Smith et al (2006), Heng et al (2006) VLT/FORS Dec 2006 2002 2000 Velocity (104 km/s) 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/SINFONI Kjaer et al 2007
Chandra & ATCA Park et al Manchester et al Gemini S + Spitzer Bouchet et al 2006 11.7 18.3
shock Te Fe Optical lines probe different temperature intervals in the cooling gas behind the radiative shocks
VLT/SINFONI March 2005 He I 2.06 PaBr[Fe II] Adaptive optics integral field unit for J, H, K Kjaer et al 2007 J-band Expansion velocities along ring
SN 1987A ring collision P. Challis/ SAINTS collab.
Two cases for the mass loss Reverse CD Blast wave Vrev Vs CSM ejecta If ej >> CSM Vs >> Vrev Type IIL, IIb SN 1993J, SN 1979C 2.ej << CSM Vs << Vrev Type IIn SN 1995N, SN 1998S SN 1987A 1. Steady wind 2. Blobs, rings, superwinds…
SN 1987A radioactivities M(56Ni) = 0.07 MO , M(57Ni) = 3x10-3 MO, M(44Ti) = 1x10-4 MO Energy stored as ionization, later released as recombination flattening of light curve
44Ti mass M(44Ti) = (0.5, 1, 2) x10-4 MO M(44Ti) = 1 x10-4 MO Range (1-2) x10-4 MOIR photometry needed
Line fluxes: H Excellent fit! But, hydrogen lines dominated by freeze out in envelope Hnot sensitive toM(44Ti)
Radio and X-ray brightening 0.5-2 keV 3-10 keV + radio 3 -20 cm Park et al 2005 Manchester et al Correlation of hard X-rays and radio probably close to reverse shock