2013/10/24

Dust emission in SNR 1987A andhigh-z dust observations
Takaya Nozawa (Kavli IPMU)〇 Contents of this talk- Introduction- Our ALMA proposals for SNR 1987A- Infrared Emission of Dust Grains- Extinction Curves in high-z Galaxies- Summary1-1. Introduction
SNe are important sources of interstellar dust?
‐huge amounts of dust grains (>108 Msun) are detectedin host galaxies of quasars at redshift z > 5➔ 0.1 Msun of dust per SN is needed to be ejected toexplain such massive dust at high-z (Dwek et al. 2007)‐contribution of dust mass from AGB stars and SNen(AGB stars) / n(SNe) ~ 10-20
Mdust = 0.01-0.05 Msun per AGB (Zhukovska & Gail 2008)
Mdust = 0.1-1.0 Msun per SN (Nozawa et al. 2003; 2007)

What composition, size, and mass of dust
can be formed in SNe?

1-2. Summary of observed dust mass in CCSNe
SN1987A
Crabtheory
missing cold dust?
optically thick clumps?

Cas A

young SNRs

swept-up IS dust?
young SNeby courtesy of M. Tanaka

FIR to sub-mm observations have revealed the presenceof massive (>0.1 Msun) dust grains in the ejecta of CCSNe

1-2. Summary of observed dust mass in CCSNe
SN1987A
Crabtheory
missing cold dust?
optically thick clumps?

Cas A

young SNRs

swept-up IS dust?
young SNeby courtesy of M. Tanaka

FIR to sub-mm observations have revealed the presenceof massive (>0.1 Msun) dust grains in the ejecta of CCSNe

2-1. Resolving cool dust in SN 87A with ALMA
ALMA Cycle 0 Proposal‘Detecting cool dust in SN1987A’

Band 7 (850 μm)

Band 9 (450 μm)（TN, Tanaka, et al.)2 arcsec

CASA simulationwith extended
config. (4 hrs)

0.1 Msun of silicate➔ 5σ detection at Band 9 !!

2-2. Successful ALMA proposals for SN 1987A

This proposal was ranked
in the highest priority !!

2-2. Successful ALMA proposals for SN 1987A

This proposal was ranked
in the highest priority !!

Our proposal was
not executedBand 9extended configuration

Band 3, 6, 7, 9
compact configuration

2-3. Our proposal for ALMA Cycle 1
ALMA Cycle 1 Proposal‘Detecting cool dust in SN1987A’（Tanaka, TN, et al.)This proposal was notranked as high priorityObserving with the resolutionof 0.25” in Bands 7 and 9➔ 10σ detection for silicate
of 0.1 Msun and 30 K

3-1. Emission and absorption efficiency of dust
○ Thermal radiation from a dust grain
Fλ ∝ 4πa2 Qemis(a,λ) πBλ(Tdust) # Qemis = Qabs
carbonsilicate(Qemis/a) is independent of aFλ ∝ 4πa3 (Qemis[a,λ]/a) πBλ(Tdust)∝ 4 Mdust κemis(λ) πBλ(Tdust)➔ IR emission is derived given Mdust, κabs, and Tdust3-2. Resolving cool dust in SN 87A with ALMA
power-law index Q∝ν-β- β = 1.0-1.5 for carbon- β = ~2.0 for silicate

flux density- Fν ∝ ν^-(4.0-4.5) for carbon- Fν ∝ ν^-5.0 for silicate○ Thermal radiation from a dust grain
Fλ ∝ 4πa2 Qemis(a,λ) πBλ(Tdust) # Qemis = Qabs

3-3. ALMA observations of high-z galazies
what can we learn from FIR observations of galaxies?
‐power-law index of emission coefficients➔ implication of dust composition‐mass of cool dust (which dominates dust mass in galaxies)➔ dust evolution history➔ depletion of carbon by combining [C II] or CO
observations‐temperature of cool dust
➔ clues to star-formation activity and compactnessof galaxies‐FIR luminosity (reflecting star formation rate)➔ corresponds UV-optical luminosity processedby interstellar dust

4-1. What are the extinction curves at high-z?
example of SED of high-z galaxies

example of extinction curves

Dwek+11‐We need to know the extinction properties to extract
the intrinsic stellar emission in galaxies‐What extinction curve is appropriate for high-redshiftgalaxies?

4-2. Observed extinction curves at high-z

Gallerani+10

SDSS J1048+4637 at z=6.2
Broad absorption line (BAL) quasars
Maiolino+04, Nature, 431, 533

different dust properties
from those at low redshift

Hjorth+13

4-3. Mass and size of dust ejected from SN II-P
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
at time of dust formation

after destruction of dust
by reverse shock4-4. Evolution of extinction curves
grain size distribution

extinction curve

MWMRN

Asano+13
Asano+12‐Large grains fromSNe and AGB stars at earlier times➔ flat extinction curve‐Small grains from shattering and growth at later times➔ steep extinction curve5. Summary
・ FIR dust emission from high-z galaxies‐mass, temperature (and composition) of dust
and FIR luminosity➔ relation between carbon dust mass andgas phase carbon ([C II] or CO)
・ Synergy with optical-to-NIR observations‐extinction curves from both theoreticalmodels and observations➔ information on the size of interstellar dust

Disclosing the evolution history of galaxies
from the origin and evolution of dust grains