claes fransson, stockholm university collaborators: r. chevalier (uva), poonam chandra (uva) p....
TRANSCRIPT
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
Dust emissionBouchet et al 2006
T ~ 166 KSi featurecollisionally heated
Spitzer
Gemini S + Spitzer
11.7 18.3
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)
broad
He 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
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?
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
Average velocity over the ring ~ 120 km s-1
UVES gives high and low velocity tails
Deprojected velocities
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
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 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 diagnostics
Gröningsson, 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
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
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
3es
cool cm
n
skm
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!
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!
1. ej >> CSM Type IIL, IIb SN 1993J, SN 1979C
Steady wind
Line width ~ Vej
2.ej << CSM Type IIn… SN 1995N, SN 1998S
Blobs, rings, short-lived superwinds… SN 1987A
Line width ~ Vblast << Vej
Two cases for the line widths
blastblastej
CSMrev VVV
2/1
blastblastej
CSMrev VVV
2/1
Reverse CD Blast wave
ejecta CSM
VsVrev
SN 1993J opticalFilippenko et al 1994Fransson et al 2004
Box-like line profiles narrow emitting shell
Transition from Type II toType Ib = Type IIb
H
He I
Cool shell behind rev. shock SN ejectapartially ionized, T<7000K fully ionized neutral, T ~ (1-3)x104 Kn ~ 1010 cm-3 n ~ 106 – 107 cm-3
H, Mg II, Fe II O III-IV, N III-V, Ne III-V
UV & optical line emission
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
HHe I
Mg II
[O III]
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/smay at be due to multiple electron scattering of narrow H emission by CS gas (Chugai 2001)
Light curve often dominatedby 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 ~ 10-4-10-3 MO 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)
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 ~ 6SN 1995N IIn N/C ~ 4SN 1993J IIb N/C ~ 12SN 1987A IIP N/C ~ 5SN 1979C IIL N/C ~ 8
Solar N/C ~ 0.25
All indicate CNO processing and mass loss and/or mixing
SN 1998S
CNO diagnostics
N/C >> 1 CNO burning heavy mass loss + mixingRotation helps!Roche lobe overflow
N/C strong fcn of mass loss40 M at ZAMSMeynet & Maeder 2003
SN 1993J binary modelWoosley et al 1994
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
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
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 ejectaLy and H from charge exchange of neutral ejecta (??) (Heng & McCray 2007)X-ray excitation by reverse shock + blobs likely. Time evol. may tell.
VLT/FORSDec 2006
2002
2000
shock
Optical lines probe different temperature intervals in the cooling gas behind the radiative shocks
Te
Fe
VLT/SINFONI
March 2005 He I 2.06 PaBr[Fe II]
Kjaer et al 2007
Adaptive optics integral field unit for J, H, K
Expansion velocities along ring J-band
Reverse CD Blast wave
ejecta CSM
VsVrev
V rev≈ ρCSMρej 1/2
V s
1. 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…
Two cases for the mass loss
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) = 1 x10-4 MO
Range (1-2) x10-4 MOIR photometry needed
M(44Ti) = (0.5, 1, 2) x10-4 MO
Line fluxes: H
Excellent fit! But, hydrogen lines dominated by freeze out in
envelope Hnot sensitive to M(44Ti)
0.5-2 keV
3-10 keV +radio 3 -20 cm
Radio and X-ray brightening
Correlation of hard X-rays and radioprobably close to reverse shock
Park et al 2005Manchester et al
Gröningsson et al (2006)Smith et al (2006), Heng et al (2006)
Velocity (104 km/s)
Reverse shock
H
Broad ~15,000 km/s emission from reverse shock going back into ejectaLy and H from charge exchange of neutral ejecta (?) (Michael et al 2003)
44Ti
reverse shock
VLT/UVES
2002
2000
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.
Mass loss rates
Type IIP dM/dt 10-6 MO yr-1 (for u = 10 km s-1). RSG wind OK
Type IIL 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 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 dM/dt 10-7 - 10-5 MO yr-1 (for u = 1000 km s-1).
Mass loss rate uncertain
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
ρcs∝ r−2ρej∝ r−n
T CS=1 . 4x109 V104km / s
2
K T reverse=T CS
n−2 2=106−107 K
R s∝t n−3 / n−2
V s∝ t−1/ n−2
Chevalier (1982)CF (1984)Chevalier & CF (1994)
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 Lx 5x1040 erg/s 50 - 200 keV
2x1039 erg/s 0.1 - 2.4 keV
t > 200 days kT ~ 1 keV Lx 1x1039 erg/s 0.1 - 2.4 keV
Transition from hard to soft spectrum!
Zimmermann & Aschenbach 2003Tem
pera
ture
(ke
V)
Days 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
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
Te
Distance from shock
M¿
5x10−5 uw/10 km s -1 M Θ /yr
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)
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
RADIOI. Free-free absorption by the CSM¿uw
¿ ¿ ¿ ¿
Twind ~ 105 K (Lundqvist & CF 1989)
Good fit to Type IIL SNe (SN 1979C, 1980K…..)
SN 1979C IIL
dM/dt = 5x10-5 – 10-4 MO/yr for u=10 km/ssuperwind phase?
Montes et al 2000
Inverse Compton scattering by photospheric photons suppressesradio at optical max.
B << e indicated by flat light curve (?)
degeneracy between B and e
Typical for galactic RSG mass loss rates
SN 2004etObs: Stockdale (2004), Beswick et al (2004), Argo et al (2005)
Type IIP
¿ 2−10 x10−6 T e
105 K 3/4
uw10 km s -1 M⊕yr -1¿
(Chevalier, CF, Nymark 2006)
Most common core collapse SN
II. Synchrotron self-absorption
F ν=R2B−1/ 2ν5/2 1−e−τ ν
τ ν ∝ν−5/ 2−α Bα+3/ 2N e
F peak , ∧ τ ν,t =1, R=V exp t ⇒B t , N e t
F ν∝ν−α
F ν∝ν5/ 2
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
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)
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
Dust in SNeAGB 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
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 circumstellarenvironment of the SN. Connection ty Type Ic SNe
Why is circumstellar interaction of SNe important?
Core collapse SNe
Type II H, He lines. H, He, O, Mg, Ca….Type Ib No H. No Si II. He, O, Mg, CaType Ic No H, He. No Si II. O, Mg, Ca
Filippenko 1997
(Filippenko 1997)
II: IIP (plateau) most common. MV ~ -16- -17. 10-15 M RSG
IIL (linear), IIn (narrow) 8-10, 15-20 M (??), binaries ?
Ib/c MV -17 - -20. WR stars > 25 M , some binaries ?
Dust temperatures and luminosity
Gerardy et al 2002
Tdust ~ 800-1300 K ~ condensation temperature
LIR + Tdust 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
Vel
ocity
(10
00 k
m/s
)
Cold dust in Cas A at 850 Dust emission between reverse and forward shocks
SCUBADunne et al 2003
Dust in Cas A
Dust + synchro Dust only
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. ?
Dust condensation
Grain comp region Tcond
Graphite C-O 1900Al2 O3 O-zone 1600Mg Si O3 O-zone 1500Fe3 O4 ? 1300SiO2 O/Si 1500
Kozasa et al 1990
Need temperature less than 2000 K
C-O shock structure
T < 1500 K, n > 1010 cm-3 behind reverse shock. OK for dust condensation
shock
Dust?
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 circumstellarenvironment of the SN.
Why is circumstellar interaction of SNe important?
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
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. ?
N/C >> 1 CNO burning
heavy mass loss + mixing
N/C increases with mass loss
Meynet & Maeder 2003
40 M at ZAMS
Mass loss processes
I. Single stars Blue SGs u ~ 500 – 3000 km/s dM/dt 10-7 – 10-5 MO /yr
Red SGs u ~ 10 – 50 km/s dM/dt 10-6 – 10-4 MO /yr
Superwinds (cf. AGB's): Heger et al (1997) find large amplitude pulsations with several MO per 10,000 years dM/dt ~ 10-4 MO/yr
II Binaries Winds RL overflow, common envelope phases....
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
T reverse=T CS
n−2 2=106−107 K
n reverse=n−4 n−3 nCS
2≈30nCS≈108−109 cm−3
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
RADIOI. Free-free absorption by the CSM
¿uw
¿ ¿ ¿ ¿
Twind ~ 105 K (Lundqvist & CF 1989)
Good fit to Type IIL SNe (SN 1979C, 1980K…..)
dM/dt = 5x10-5 – 10-4 MO/yr for u=10 km/s
II. Synchrotron self-absorption
F ν=R2B−1/ 2ν5/2 1−e−τ ν
τ ν ∝ν−5/ 2−α Bα+3/ 2N e
F ν∝R2Bα+1N e ν−α τ <<1
F ν∝R2B−1/2ν5/2 τ >>1
F peak , R=V expt ∧ τ ν,t =1 ⇒ B t , N e t
F ν∝ν−α
F ν∝ν5/ 2
Absorption by same rel. electrons as are emitting
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 MO/yr for u=10 km/s, same as from X-rays3. Injection spectrum nrel -2.1. Synchrotron cooling steepens this!4. B 0.15 e 10-4
Assume: UB Utherm, Urel Utherm
Self-consistent calculation of rel. electron spectrum, including all cooling processes, as well as radiative transfer
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
H profile in SN 1998SFransson et al 2004
Double peaked H profile implies thin shell If R/R < vth/Vexp~10-3 Sobolev not valid. Optically thick lines F
M-shaped profiles
Confirms line formation in cold, dense shell R < 1013 cm. Consistent with photoionization models
see alsoLeonard et al 2000Gerardy et al 2000Poozo et al 2004
X-rays from Type IIP
SN 1999em, SN 1999gi, SN 2004dj, ……..
Lx ~ (1-5)x1038 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
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
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.
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
SN classification
Type Ia Early: No H, He. Si II 6150 line. Late: Fe II-IIIType II H, He lines. H, He, O, Mg, Ca….Type Ib/c No H, He (Ic). No Si II. O, Mg, Ca
Filippenko 1997
(Filippenko 1997)
Ia : Standard candles (almost!). Thermonuclear explosions of 1.4 M white dwarfCore collapseII: IIP (plateau) most common. MV ~ -16- -17. 10-15 M RSG IIL (linear), IIn (narrow) 8-10, 15-20 M (??), binaries ?Ib/c MV -17 - -20. WR stars > 25 M , some binaries ?
Good fit with SSA.Inverse Compton cooling by photospheric photons important. LBol peaks at ~ 10 days
Berger, Kulkarni, Chevalier 2002
Björnsson & CF 2003
Type Ic SN 2002ap
Can only determine from SSA alone
¿ u ¿
SN 1993J X-raysXMM: Zimmermann & Aschenbach 2003Chandra: Swartz et al 2003
ThermalkT ~ 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
SN 1993J
SSA + free-free
SSA only
dM/dt = 5x10-5 MO/yr for u=10 km/s
Fit to each epoch + radius B(t) & N(t)
CF & Björnsson 1998
Magnetic field and rel. particle density
1. Wind B-field 1-2 mG at 1016 cm (Cohen et al 1987)
Amplification of B-field behind shock. Weibel instab.? (Medvedev & Loeb 1999)2. UB 0.15 Utherm i.e. B 0.15 e 10-4
3. Ue 10-4 Utherm
B=64 Rs
1015 cm −1
G−2
U e=εe U therm=εe98ρV s
n rel∝ ρV s2
n rel∝ nwind
log R log R
log
B lo
g
ne
Note : If ne() ~ np(), then p ~ mp/me e ~ 0.2 ??
Obs: VLA: van Dyk et al 1994,
Weiler, Panagia, Sramek 2002
CF & Björnsson 1998
Model and VLA light curvesAssume B and e constantSelf-consistent calculation of rel. electron spectrum, including all cooling processes, as well as radiative transfer
Synchrotron cooling gives
Cooling break observed with GMRTand VLA at ~3400 days close to predicted (Chandra et al 2004)
Weiler et al, KITP 2006Type Ic SNe
GRB connection
SN 1994I in M 51‘best case’
Steep light curves F t-1.2
Chevalier 1998
SSA
FF
Free-free vs synchrotron self-absorption
High & low V F-F; Low & high V SSA¿ u ¿ ¿ u ¿
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
¿u V 2¿ ¿ ¿¿
10−5 M O /yr¿ ¿ ¿ u
1000 km/s −1
¿ εB≈2 εrel ¿V exp=70 ,000 km/s ¿ ¿ ¿
1. If
2. If
¿10−5 M O /yr ⇒ ε B≈5x10−3¿¿ 5x10−7 M O / yr ¿ Low for WR star!
day 6
(Björnsson & CF 2003)
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 radioactivitySynchrotron? Too low if extrapolated from X-rays
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?
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
1 103 107
E ~ mp
E2 d
N/d
E
radio X-rays
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 curvesChevalier + CF 2006
X-rays
radio
ICCR mod.synchro
‘stand.’ synchro
IC
synchro
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 ne -2.1 in SN 1993J.
4. B 0.15 e 10-4. (Note : If ne() ~ np(), then
p ~ mp/me 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
Shock structure
Chevalier & Blondin 1995
Fransson et al 1996
CS shock adiabatic
Reverse shock radiative
Ti
Te
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.