nitors: Mass loss determines SN Type. IIP (little mass lost), ....IIn, IIb ( < 0.5 M of H envelope nly He core), Ic (only O core) a structure: Shock dynamics probes density structure ejecta physics: Thermal radiation processes (X-rays) Non-thermal radiation processes (radi Relativistic particle acceleration Dust production GRB connection: GRB afterglow determined by circumstellar onment of the SN. is circumstellar interaction of SNe importan
Why is circumstellar interaction of SNe important?. 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 - PowerPoint PPT Presentation
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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
t > 200 days kT ~ 1 keV Lx 1x1039 erg/s 0.1 - 2.4 keV
Transition from hard to soft spectrum!
Zimmermann & Aschenbach 2003Te
mpe
ratu
re (k
eV)
Day after explosion
X-ray evolution
At 10 days: Only X-rays from outer, CS shock T~109 KAt 200 days: X-rays from reverse shock dominates T~107 K
CF, Lundqvist & Chevalier 1996
Hard to soft evolution natural consequence of the cool shell
X-ray spectra useful probes of theejecta composition
solar helium zone
carbon zone oxygen zone
Nymark et al 2006
Nymark, Chandra, CF 2007data: XMM Zimmermann & Aschenbach Chandra: Swartz et al 2003
SN 1993J
CNO enriched H or He envelope
Cool shell, reverse shock SN ejectapartially ionized, T<7000K fully ionized neutral, T ~ (1-3)x104 KH, Mg II, Fe II O III-IV, N III-V, Ne III-V
UV & optical line emission
SN 1993J
Good fit with ejecta + cool, dense shellShock at ~ 10,000 km/sConsistency of X-ray flux and UV/optical flux
HST (SINS) + Keck
HHe I
Mg II
[O III]
SN 1979CIIL
Montes et al 2000
1.3 cm 21 cm
SN 1993JIIb
Van Dyk et al 1994, Weiler, Panagia, Sramek 2002
Radio light curves
RADIO
Free-free absorption by the CSM
wwe
we
uMtV
uMTdrrn
tVrur
Mrn
.
33exp
2.
2/322
exp2
.
1)()()()(
4)(
Twind ~ 105 K (Lundqvist & CF 1989)
Good fit to Type IIL SNe (SN 1979C, 1980K…..)
Reliable mass loss rates needcalculation of Twind
Synchrotron self-absorption
1
1
)(
/
)1)((
2/52/12
rel12
rel2/32/5
2/52/1
)(2
BRF
NBRF
NB
BjS
eSRF
)(),(1),(&exp tNtBttVR rel
F
2/5F
SN 1993J
SSA + free-free
SSA only
Fransson & Björnsson 1998
Magnetic field and particle density in SN 1993J
1. Wind B-field 1-2 mG at 1016 cm (Cohen et al 1987)
Amplification of B-field behind shock. Turbulence? (Jun & Norman 1996)2. UB/Utherm 0.15 3. Urel Utherm
GcmRB s
1
151064
)2/()3( nnmtR ms
22relthermrelrel 8
9 tρVUU s
2srel ρVn
windrel nn
Obs: VLA: van Dyk et al 1994,
Weiler, Panagia, Sramek 2002
CF & Björnsson 1998
Model and SN 1993J VLA light curves
csm r-2 OK!! No evidence for mass loss variations or s 2.2. dM/dt = 5x10-5 MO/yr for u=10 km/s, same as from X-rays3. Injection spectrum nrel -2.1. Synchrotron cooling steepens this!
Assume: UB Utherm, Urel Utherm
Self-consistent calculation of rel. electron spectrum, including all cooling processes, as well as radiative transfer
Chevalier 1998
SSA
FF
Free-free vs synchrotron self-absorption
VLBI and H velocity for different ejecta models
Red = HBlack = VLBI/1.3
VLBI and H velocity evolution require asteep density gradient at ~ 13,000 km/s
Mass loss rates
Type IIP's dM/dt 10-6 MO yr-1 (for u = 10 km s-1). RSG wind OK
Type IIL's dM/dt 2x10-5 – few x 10-4 MO yr-1 (for u = 10 km s-1). 'super wind' (Heger et al) t = Vs/u tobs 5x102 tobs > 104 / (u/10 km s-1) yrs i.e., several MO lost
Type IIn's dM/dt 10-4 -10-3 MO yr-1 (for u = 10 km s-1). super wind Clumping (Chugai)? Asymmetric wind (Blondin, Chevalier, Lundqvist)?
Type Ib/c's dM/dt 10-7 - 10-5 MO yr-1 (for u = 1000 km s-1). WR stars? Mass loss rate uncertain
SN 1979C (IIL), 1987A (IIP), 1993J (IIb), 1995N (IIn), 1998S (IIn) all have N/C >> 1 (Fransson et al 1989, 2001, 2004)
N/C strong fcn of mass loss40 M at ZAMSMeynet & Maeder 2003
SN 1993J modelWoosley et al 1994
N/C >> 1 CNO burning heavy mass loss + mixing
N/C strong fcn of mass lossMeynet & Maeder 1992
SN 1993J modelWoosley et al 1994
Conclusion of CNO:
SN 1993J modelWoosley et al 1994
Progenitors must have lost most of the hydrogen envelopebefore explosion
Confirms mass loss as the important factor for the SN Type
SAINTS collab.SN 1987A ring collision
Origin of the rings
R ~ 1018 cm, Vexp ~10 km s-1 tdyn ~2x104 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)
Chandra & ATCA
Park et alManchester et al
Dust emissionBouchet et al 2006
T ~ 166 KSi featurecollisionally heated
Spitzer
Gemini S + Spitzer
11.7 18.3
Gröningsson et al 2006
VLT/UVES
FWHM ~ 6 km s-1
Seeing 0.5-0.8”
Resolves N/S
Gröningsson et al 2006
H
narrow
[O III] 5007
Narrow FWHM ~ 10 km s-1 from unshocked ring Broad Vmax 300-400 km s-1 from shocked ring (Pun et al 2002)
broadHe I
Gröningsson et al (2006)Smith et al (2006), Heng et al (2006)
Velocity (104 km/s)
Reverse shock
Broad ~16,000 km/s emission from reverse shock going back into ejecta
VLT/FORSDec 2006
2002
2000
Intermediate velocity lines from shocked ringprotrusions
Gröningsson et al 2006
Oct 2002
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
Kjaer et al 2007
Adaptive optics integral field unit for J, H, K
Expansion velocities along ring J-band
VLT/UVES spectrum
Max. velocity ~ shock velocity ~ 300-400 km/s
Coronal lines Gröningsson et al 2006
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 intoring protrusions
Borkowski et al 1997Pun et al 2002
Hydrodynamics of ring collision
Optical emission from radiativeshocks into the ring materialRadio and hard X-rays from reverse shock
Borkowski et al 1997
shock
Radiative shock structure
Post-shock densities ~5x106 - 107 cm-3. Agrees with nebular diagnostics
photoion. precursor narrow Ha, [N II], [O III]
coll. ioniz. X-raysCoronal lines
photoion. broad H, [OIII],…
Vs = 350 km/s no = 104 cm-3
shock
Optical lines probe different temperature intervals in the cooling gas behind the radiative shocks
Te
Fe
Shock velocity into hot-spots 300 – 400 km s-1 Ts ~ 2x106 K
Coronal lines complement the X-rays to probe whole temp. range
Shock velocity
Coronal line diagnosticsGröningsson, Nymark…
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 (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
Coronal lines and soft X-rays correlate. Soft X-rays from hot-spots. Hard from reverse shock & blast wave
Optical: Gröningsson et alX-rays: Park et al 2005
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
Cooling shocks
1
4
3.4
1 103008
3
escool cm
nskm
Vt 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 linesUnshocked ring ionized by SN shock breakout, then recombiningRing 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-raysin pre-shock gas are re-emitted as [O III]
We are now starting tosee the re-ionization of the ring!