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

The Dark Ages VIrtual Department DAVID The Dark Ages VIrtual Department http://www.arcetri.astro.it/david 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

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=100-10000!

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

Sticking coefficient: Dust masses from Nozawa et al. 2007 Mdust = 0.1-0.5 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)

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

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

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)

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

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

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

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

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)

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.