Supernovae as sources ofinterstellar dust
Takaya Nozawa(IPMU, University of Tokyo)
Thanks to:T. Kozasa (Hokkaido Univ.), N. Tominaga (Konan Univ.)
K. Maeda, M. Tanaka, K. Nomoto (IPMU, Univ. of Tokyo)
H. Umeda, I. Sakon (University of Tokyo)

2011/06/21

Outline
1. Introduction
2. Formation and evolution of dust in Type IIb SNewith application to Cassiopeia A SNR

3. Missing-dust problem in core-collapse SNe
4. Formation of dust in the ejecta of SNe Ia
5. Summary

1. Introduction

1-1. Dust formation in primordial supernovae
Supernovae are important sources of dust?
・ Evolution of dust throughout the cosmic age－ A large amount of dust (> 108 Msun) in z > 5 quasars➔ 0.1-1.0 Msun of dust per SN must be ejected－ Inventory of interstellar dust in our Galaxy
・ Theoretical studies on dust formation in the SN ejecta(Todini & Ferrara’01; Nozawa+’03; Schneider+’04;
Bianchi & Schneider+’07; Cherchneff & Dwek’09, 10)－ Mdust=0.1-1 Msun in (primordial) Type II-P SNe (SNe II-P)－ Mdust=1-60 Msun in pair-instability SNe (PISNe)
its presence has not been proved observationally1-2. Dust destruction in supernova remnants
・ a part of dust grains formed in SNe are destroyed due
to sputtering in the hot gas swept up by the shocks(e.g., Bianchi & Schneider’07; Nozawa+’07, 10)➔ destruction efficiency of dust depends on the initialsize distribution

・ It is necessary to treat formation and destruction ofdust self-consistently
He coreFSRSCD

1-3. Mass and size of dust ejected from SN II-PPISNe
SNe II-P

total dust mass surviving thedestruction in Type II-P SNRs;
0.07-0.8 Msun (nH,0 = 0.1-1 cm-3)

size distribution of dust after
RS destruction is domimatedby large grains (> 0.01 μm)

Nozawa+’07, ApJ, 666, 955
at time of dust formation

after destruction of dust
by reverse shock2. Formation and evolution of dustin SNe IIb: Application to Cas A

2-1. Dust formation in Type IIb SN○ SN IIb model (SN1993J-like model)－ Meje = 2.94 Msun
MZAMS = 18 Msun
MH-env = 0.08 Msun
－ E51 = 1.0－ M(56Ni) = 0.07 Msun

2-2. Dependence of dust radii on SN type
SN IIbSN II-P0.01 μm

SN Ib (SN 2006jc)－ condensation
timedust(Nozawaet al.of2008)
300-700 d after explosion－ total mass of dust formed
・ 0.167 Msun in SN IIb
・ 0.1-1 Msun in SN II-P
Nozawa+’10, ApJ, 713, 356－ the radius of dust formedin H-stripped SNe is small
・ SN IIb without massive
H-env ➔ adust < 0.01 μm
・ SN II-P with massive
H-env ➔ adust > 0.01 μm

2-3. Destruction of dust in Type IIb SNR
homogeneous CSM (ρ = const)stellar-wind CSM (ρ ∝ r-2)
330 yrnH,1 = 30, 120, 200 /cc ➔ dM/dt = 2.0, 8.0, 13x10-5 Msun/yr for vw=10 km/s

Almost all newly formed grains are destroyed in shockedgas within the SNR for CSM gas density of nH > 0.1 /cc➔ small radius of newly formed dust
➔ early arrival of reverse shock at dust-forming region
Nozawa+’10, ApJ, 713, 356

2-4. IR emission from dust in Cas A SNRAKARI corrected 90 μm image

・ total mass of dust formed
Mdust = 0.167 Msun・ shocked dust : 0.095 Msun
Md,warm = 0.008 Msun
・ unshocked dust :Md,cool = 0.072 Msun
with Tdust ~ 40 K
Nozawa+’10, ApJ, 713, 356

AKARI observation
Md,cool = 0.03-0.06 Msun
Tdust = 33-41 K(Sibthorpe+10)

Herschel observation
Md,cool = 0.075 Msun
Tdust ~ 35 K (Barlow+10)

3. Missing-dust problem in CCSNe

3-1. Difference in estimate of dust mass in SNe
・ Theoretical studies－ at time of dust formation : Mdust=0.1-1 Msun in CCSNe(Nozawa+’03; Todini & Ferrara’01; Cherchneff & Dwek’10)－ after destruction of dust by reverse shock (SNe II-P) :Msurv~0.01-0.8 Msun (Nozawa+’07; Bianchi & Schneider’07)

dust amount needed to explain massive dust at high-z
・ Observational works－ NIR/MIR observations of SNe : Mdust < 10-3 Msun(e.g., Ercolano+’07; Sakon+’09; Kotak+’09)－ submm observations of SNRs : Mdust > 1 Msun
(Dunne+’03; Morgan+’03; Dunne+’09)－ MIR/FIR observation of Cas A : Mdust=0.02-0.075 Msun
(Rho+’08; Sibthorpe+’09; Barlow+’10)

3-2. Missing-dust problem in CCSNe
Tanaka, TN, et al. 2011, submitted

theoryhigh optical depth
or cold dust ??

grain growth orformation in CDS??
confusion
with IS dust??

Middle-aged SNe with ages of 10-100 yrs are goodtargets to measure the mass of dust formed in SNe!!

3-3. Search for dust in middle-aged CCSNe－ silicate－ dust temperture ~ 230 K－ dust mass ~ 10-3 Msun

SN 1978K : Type IIn SNe
X-ray bright, massive CSM➔ the dust is likely to beof circumstellar origin

3-4. Estimate of dust mass in middle-aged SNe
Tanaka, TN, et al. 2011, submitted

What is temperature of newly formed but unshocked dust?

Massive dust can behidden if Tdust < 100 K

3-5. Temp. of cool dust and its detectability
Tanaka, TN, et al. 2011, submitted

0.1 Msunheating sources of dust
・ 44Ti ➔ ~1036 erg/s
・ X-ray emission➔ a few x1036 erg/s

LIR < Ltot < 1037 erg/s➔ Tdust < 45 K for 0.1 Msun
Tdust < 90 K for 10-3 Msun

・ Possible targets
SN 1978K, 93J, 04dj, 04et

3-6. Non-dimming of optical light curves
Formation of massive dust 2-3 years after explosions
should leds to the fading optical light curves of SNe
・ Reducing (effective) optical depth in optical bands➔ condensation of dust in dense clumps➔ much lower opacity for large grain (adust > 1.0 μm)
・ Delayed condensation of dust
➔ slower cooling of the gas in the ejecta➔ grain growth of pre-existing circumstellar dust
➔ formation in cool dense shell・ No formation of massive dust
➔ Theoretical studies overestimate dust masssticking probability = 1.0

4. Formation of dust in SNe Ia

4-1. Dust formation in Type Ia SNe○ Type Ia SN modelW7 model (C-deflagration) (Nomoto+’84; Thielemann+’86)－ Meje = 1.38 Msun

－ E51 = 1.3－ M(56Ni) = 0.6 Msun

0.1 Msun of C and O
remains unburnedin the outermost layer
with MC/MO ~ 1

4-2. Dust formation and evolution in SNe Ia
average radiusTN, Maeda, et al. 2011 in press

dust destruction in SNRs
0.01 μm

・ condensation time :100-300 days
・ average radius of dust :aave <~ 0.01 μm
・ total dust mass :Mdust = 0.1-0.2 Msun

newly formed grains arecompletely destroyed for
ISM density of nH > 0.1 cm-3
➔ SNe Ia are unlikely to bemajor sources of dust

4-3. Optical depths by newly formed dust
V band (0.55 μm) opacity at 300 days for γ = 1
MC= 0.006 Msun
Msilicate = 0.030 Msun
MFeS = 0.018 Msun
MSi= 0.063 Msun

τC= 22
τsilicate = 0.01
τFeS = 14
τSi= 78

Mtotalτtotal= 0.116 Msun

= 114

V band (0.55 μm) opacity at 300 days for γ = 0.1
Mtotal~ 3x10-4 Msun

τtotal=1

Formation of dust grains (C, Si, and Fe) should be
suppressed to be consistent with the observations

4-4. Carbon dust and outermost layer of SNe Ia
・ There has been no evidence for dust formation in SNe Ia➔ Formation of massive carbon dust does not matchthe observations
Observational data : SN 2005df at
day 200 and 400 (Gerardy+’07)－ massive unburned carbon(~0.05 Msun) in deflagration➔ change of compositionof WD by He-shell flash➔ burning of carbon by adelayed detonation

observationally estimatedcarbon mass in SNe Ia :Mc < 0.01 Msun
TN, Maeda, et al. 2011 in press(Marion+’06; Tanaka+’08)

4-5. Dust formation in super-Chandra SNe?
－ super-Chandra SNe :M(56Ni) ~ 1.0 Msun

SN 2009dc, Tarbenberger+’10

detection of CII line
➔ presence of massive
unburned carbon

enhanced fading at ~200 day➔ formation of carbon dust?

5. Summary of this talk・ Size of newly formed dust depends on types of SNe－ H-retaining SNe (Type II-P) : aave > 0.01 μm－ H-stripped SNe (Type IIb/Ib/Ic and Ia) : aave < 0.01 μm➔ dust is almost completely destroyed in the SNRs
➔ H-stripped SNe may be poor producers of dust
・ Our model treating dust formation and evolution self-consistently
can reproduce IR emission from Cas A

・ Middle-aged SNe with the ages of 10-100 yr are good targets tomeasure the mass of dust formed in SNe－ We detect emission from SN 1978K, which is likely from shocked
circumstellar silicate dust with 1.3x10-3 Msun
－ The non-detection of the other 6 objects seems to be natural
because our present search is sensitive only to Ltot >1038 erg/s・ Mass of dust in young SNRs may be dominated by cool dust
➔ FIR and submm observations of SNRs are essential