Dust in SNR 1E 0102.2−7219

Karin M. Sandstromet al. 2009

1

Dust, a crucial component

• for interstellar chemistry• regulates thermal balance• A Shield for dense clouds

2

Mid-IR emission from Newly Formed Dust

• ∼ 400 and 800 days after the explosion– SN 1987A 10^-4 ∼ M sun of dust produced by 775

days after the explosion– SN 1990I (Elmhamdi et al. 2004)– SN 2006jc (Smith et al. 2008; Nozawa et al. 2008)– (other source: IR light echoes)

• Reverse shock reheats the newly formed dust

3

Introduction to 1E 0102.27219

• Young(adopt a value 2000yr)

• 190,000 ly• R.A. 01h04m02.s1 decl.

−72◦0152.5(J2000)• oxygen-rich• Type Ib/Ic or IIL/b SN (Blair et

al. 2000; Chevalier 2005)

• Blast wave radius 22’’∼• Reverse shock radius 15’’∼

T. J. Gaetz, 2000APOD, April ,14, 2000 4

Mid-IR spectrum of E 0102

5

cartoon cross-section of E 0102

6

SCSM

• “forward-shocked CSM/ISM”• outer radius at 6.6 pc, inner radius at the ∼

contact discontinuity• Radio & outer part of X-ray• Te ~ 1keV (10^7 K)

7

NRSE

• “nonradiative shocked ejecta”• outer radius at the contact discontinuity, inner

radius at 4.5 pc∼• Te ~0.4 keV (5×10^6 K)

8

RSE

• “radiative shocked ejecta”• reverse shock encounters dense clumps of

ejecta• the brightest optical emission lines from these

shocks is the [O iii] line at 5007 Å

9

USE

• ?

10

Results of the decomposition• All of the line emission

is found to come from the radiative shocked ejecta (RSE)

• NRSE shows dust continuum but no emission lines

• SCSM spectrum also has a small dust emission component that peaks around 20 μm.

11

Modeling the Dust Emission

• Unmixed• Model in Nozawa et al. (2003)

amorphous carbon in the He-rich layersMg2SiO4(forsterite) and MgO in the O–Mg–Si layerMgSiO3 and SiO2 in the O–Si–Mg layersilicon and iron rich species in the deeper nucleosynthetic

layers

• how deeply into the ejecta the reverse shock has propagated

• what species of dust we should include.

12

Dust model in E 0102

• magnesium is 2 times more abundant than ∼silicon (Flanagan et al. 2004).

• the primary species :– amorphous carbon– Al2O3

– forsterite – MgO

13

Dust Model Fit Results

• involves the four grain species discussed above with a fixed size of 0.1 μm.(For dust grains in the Rayleigh limit the dust mass is independent of the grain size)?

• Parameter: the mass of dust in each species and its temperature

14

Dust Model Fit Results

15

(b)from Laor & Draine (1993).

16

Implications for Dust Production in CCSN andComparison with Previous Results

• With Cas A– Mixedunmixed– Species S, Ar, Ca, Fe O, Ne, Mg– Mass and temperatureof dust

• For Cas A , Rho et al. (2008) find on the order of 0.02−0.05 Msun of dust. two temperature components of Am.carbon at

80 and 200 K totaling 1–2 × 10^-3 ∼ ∼ ∼ Msun and 0.6–∼1.4 ×10^-2 Msun of FeO at 60 K.∼

• For E 0102, 3 × 10^-3 Msun am.carbon at 70K, 2 × 10^−5 Msun Mg2SiO4 at 145K

• An ejecta knot in N 132D• CCSN and newly dust formation

17

Problem

• find substantially less amorphous carbon dust than predicted by dust condensation models.(outermost layers of the ejecta)

• have no constraints on the initial grain size, so it is difficult to estimate how much of the dust in the remnant has been destroyed up to this point

• The contribution to the IR continuum from MC or other kind of dust

• The mid-IR observations are not sensitive to cold dust present in the remnant

18

SUMMARY AND CONCLUSIONS

• Fine-structure emission lines of oxygen and neon on top of emission from warm dust.

• Decomposition of the spectrum. Emission and continuum…

• Best fit model ： 3 × 10^-3 Msun am.carbon at 70K, 2 × 10^−5 Msun Mg2SiO4 at 145K

19

Thanks

20