1. Dust Formation and Survival in Supernova Ejecta
Simone Bianchi
Raffaella Schneider
INAF-Osservatorio Astrofisico di Arcetri,
Florence, Italy

2. The Dark Ages VIrtual Department
DAVID
The Dark Ages VIrtual Department
S. Bianchi
INAF/Arcetri
B. Ciardi
MPA
P. Dayal
SISSA
C. Evoli
SISSA
A. Ferrara
SNS Pisa
S. Gallerani
OARoma
F. Iocco
IAP
F. Kitaura
SISSA
M. Mapelli
ETH
A. Maselli
MPA
R. Salvaterra
INAF/Milano
S. Salvadori
SISSA
R. Schneider
INAF/Arcetri
L. Tornatore
INAF/Trieste
M. Valdes
IPMU
R. Valiante
Univ. Firenze

3. Dust formation in Type II SN (Bianchi & Schneider 2007, MNRAS 378, 973)
Revisitation of the model of Todini & Ferrara (2001)
SN progenitor of different masses and metallicities.
Metal yields from SN models (Woosley & Weaver 1995)
Ejecta of homogeneous density and metal composition
(mixed case in Nozawa et al. 2003)
Adiabatic expansion with initial conditions matching SN 1987A
SiO and CO molecule formation and destruction
nucleation theory:
supersaturation, nucleation & accretion
Distruzione molecole: radioactive decay (Co-56 produce gamma-rays che riscaldano elettroni per effetto Compton, questi distruggono CO e SiO, SiO anche distrutto da collisioni con Ne+, con trasferimento di carica).
Formazione molecole per radiative association con emissione di fotoni.
Compatto (1000UA, 1/100 pc), quindi tau= !

4. Size distribution
Nozawa et al. 2003
Discretization & limits of standard nucleation theory
Difference in assumptions for molecule formation:
CO vs AC grains

5. Sticking coefficient:
Dust masses
from Nozawa et al. 2007
Mdust = Msun
formed in < 1000 days
Limits of standard
nucleation theory
Alla fine: fino a qui si vede cosa succede alla polvere entro pochi anni dalla SN.
Siamo andati a vedere cosa succede dopo, durante l’evoluzione del resto di SN
Sticking coefficient:
1 (used in models) vs
0.1
(experiments, Gail 2003)

6. Dust survival in SNR (Bianchi & Schneider 2007, MNRAS 378, 973)
Dynamic of shock fronts from Truelove & McKee (1999)
with Rankine-Hugoniot jump conditions
Dust sputtering in shocked ejecta
forward shock
border ejecta/ISM
shocked ejecta
dust sputtering here!
reverse shock
ISM
shocked
ISM
unshocked ejecta

7. Size distribution & dust masses
Dust grain erosion
20% survives 7% 2%
Dust evolution in less then
1-2 ×105 years
from
Nozawa et al. 2007

8. Extinction law IMF averaged after reverse shock Extinction in a
z=6.2 LoBAL QSO
(Maiolino et al. 2004)
Low ionization Broad Absorption Line QSO, grandi densità di colonna, estinti a z < 4, confrontato con un no Bal per
Derivare la curva di estinzione
Shape given by
Amorphous Carbon
(Zubko et al. 1996)

9. Extinction law but which Amorphous Carbon? Zubko et al. 1996
dashed:
dotted
Jäger et al. 1998

10. Extinction law
Hirashita et al. 2008
mainly SiO2
dashed:
dotted

11. Emissivity ελ=40 cm2/g (100 μm/lambda)1.4 Weingartner & Draine (2001)
Nozawa et al (2003)
as quoted by
Dunne et al (2009)
ελ=40 cm2/g (100 μm/lambda)1.4

12. Emissivity Required by Cas A Dunne et al (2003; 2009)
Zubko et al. 1996
Jäger et al. 1998

13. Cas A Dust Emission 1-T fit T = 80 K Mdust= 4 ×10-3 Msun 2-T fit
Tc = 35 K
Mdust= 0.1 Msun
Datapoints from Hines et al. (2004)
Consistent with
Rho et al. (2008)

14. Summary
Models of dust formation could be consistent with observations of dust in Type II SN, but better theory & parameter constraints are needed.
Only a qualitative agreement between different models.
A large fraction (90%) of dust is destroyed by the reverse shock within 105 yr from its formation before reaching the ISM.