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Dust Formation in the Early ( z >6) Universe. S. V. Marchenko Western Kentucky University. General importance. ~50% of the optical radiation emitted since the Big Bang by all sources in the universe has been ‘reprocessed’ by dust
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Dust Formation in the Early (z>6) Universe S. V. Marchenko Western Kentucky University
General importance • ~50% of the optical radiation emitted since the Big Bang by all • sources in the universe has been ‘reprocessed’ by dust • cooling (e.g. [CII] 157.7 m) accretion star formation rates • (massive, M> 30 M stars) IMF • assembly of H2 on dust grains is far more efficient than in the • gas phase • dust in Lyman break galaxies at z~5 ? (Ando et al. 2004; Ouchi • et al. 2004) • CMB distortions; far-IR (=0.4-1.0 mm: Elfgren & Desert 2004) • background Can we see a z~10 object?
SFR and dust Star formation rates and dust attenuation: GALEX/UV (Schiminovich et al. 2005)
Dust z~0: gen. Info Stars Dust (MW Galaxy: Gehrz 1989) AGB (C, OH/IR, Miras) RSG ~ 10-3 M/yreach SNe PNe ~ 10-4 M/yreach Wolf-Rayet Presently, WRs produce <1% of the dust galaxy-wide. Molecular clouds: 1-5times the stellar rate
Dust z>>0 - 1 Stars Dust (z>>0) M(ini) Dust M mass/* (M ) composition size __________________________________________________________________ SNe(PopIII) 140-260 ? ? ? SNe II 8 0.1-0.3, Z<<Z ? ? 3 , Z~Z Si, C, Fe(?) ‘standard’?, ~1m LBVs 75-85 ? Z<<Z ? ? 30(?)0.01-0.25, Z~Z Si, PAH, Al(??), ~1m + C ‘small’ WCd 60-70 ? Z<<Z ? ? 3010-3 -10-2 , Z~Z C(amorph.) ~1m+ ‘small’
Dust z>>0 - 2 Stars Dust (z>>0) M(ini) Dust M mass/* (M) composition size __________________________________________________________________ sgB[e] ? ? Z<<Z ? ? 30-60 ? Z~Z Si ~1m B[e]WD 5(?) ? ? ? RSG 8-50 ? Z<<Z ? ? 8-2510-4 -10-3, Z~Z Si ~0.5m+ ‘standard’ AGB 1-(5-6) Mini(Z/Z), Z<<Z ? ? (OH/IR) 1-6 ~10-3 Mini, Z~Z Si, C, ice ‘stand.’(?)
SN - facts Dust in core-collapse SNe Evidence: - isotopic abundance ratios of grains in meteorites (excess of 13C, 15N, 18O, etc. - Travaglio et al. 1999) - near-mid-IR (~1-2 yrs after explosion), sub-mm excesses - blueshifted emission lines HOW MUCH DUST ?? Theory: up to ~1M/expl.(Todini & Ferrara 2001) Observations: ~10-3-10-2 M (mid-IR: Dwek 1993; Pozzo et al. 2004) ~1-2M [sub-mm: Dunne 2003, Morgan 2003] Primordial (WR, LBV, RSG) dust? – SN2002hh [Barlow et al.2005], SN 2002ic (Kotak et al., 2005)
SN – 1987A Preexisting dust? Light echoes in SN1987A: HST/WFPC2, F656N (Sugerman et al. 2005)
LBVs LBVs: preexisting dust (RSG/BSG)? AG Car: 12.5 μm (Voors et al. 2000) η Car: Smith et al. 2002 η Car: L band, Chesneau et al. 2005
RSG RSGs: in situ dust VY CMa (M5e Ia): Smith et al., 2001
WR104, pinwheel WR104: WC9d+B0.5V(+VB), P = 220 d April-June1998, Keck, H-K interferometry: Tuthill et al. (1999) _______________________ 150 mas
WR48a, Gem WR48a: WC8ed+? March 2004, Gemini-South/TReCS, 12.3 m
WR112, animation WR 112 (WC9d+OB?) Gemini, 12.5 m: 2001 vs. 2004 P ~ 12 y, D ~
WR112, july 2004 July 2004, Gemini-South/TReCS; 12.3 m
WR112, dust survival … at least 20% of the initially formed dust survives the first ~100 years of expansion in a shocked environment… (Marchenko et al. 2002)
Z-depend. For WRs Meynet & Maeder (2005) Does dust production depends on Z? Binaries? – some [limited] help?
Model-1 • MODEL: modified from Loeb & Haiman (1997) • dust absorption coefficient • dust opacity • - for SMC (Cartledge et al. 2005) • - for MWG (Mathis 1990) • dust density • i - different categories of dust-producers: SN, massive stars, AGB • mass fraction of the deposited dust • or 10 z 20 • z 10
Model-2 • - mass fraction of dust (efficiency of dust formation): • - Z-dependent for massive stars (Vink et al. 2001), • AGBs (van Loon 2000, C-rich class] • efficiency of star formation • (BH, NS, WD) • - from Drory et al. (2005) • mass fraction of collapsed barions • - standard CDM cosmology (Haiman & Loeb 1997) • - evolutionary timescales • 1, for z zcr,i • 0, for z > zcr,i
SMCvsMWG Chemistry: SMC vs. MWG
Dust outp.: SN Dust output from SNII; theory: Todini & Ferrara 2001
Dust yields Left – pessimistic: SNII – 1/10 theory, Massive st. - Right – optimistic (realistic?): SNII – 1/30 theory, Massive st. -
Conclusions • Conclusions: • Dominance of SNII at z>3 …IF dust can form in SN • ejecta… • ~10 overestimated theoretical for SNII • (cf. SN 2002hh: Barlow et al. 2005) • Fairly short dust-survival times, T 0.4 Gyr, in line • with Jones et al. (1994)
Things to do • Things to do: • Dust formation and dust survival in the SN ejecta • (SEEDS collaboration, PI M.J. Barlow) • Dust formation/survival in the winds of massive stars • Dust formation (efficiency) and dust chemistry at Z~0