dust in the early universe and the contribution of agb stars · 2014-09-01 · dust in the early...
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Dust in the early universe and the contribution of AGB stars
Raffaella Schneider INAF/Osservatorio Astronomico di Roma
Matteo de Bennassuti (INAF/OAR)
Luca Graziani (INAF/OAR)
Stefania Marassi (INAF/OAR)
Rosa Valiante (INAF/OAR)
In collaboration with: Marcella di Criscienzo (INAF/OAR) Flavia dell’Agli (INAF/OAR) Paolo Ventura (INAF/OAR) Corinne Rossi (La Sapienza) Marco Limongi (INAF/OAR) Alessandro Chieffi (INAF/OAR)
Simone Bianchi (INAF/OAA) Gen Ciaki (Tokyo University) Simona Gallerani (SNS) Takaya Nozawa (IPMU) Kazuyuki Omukai (Tohoku University) Stefania Salvadori (Kapteyn) Naoki Yoshida (Tokyo University)
dust in the early Universe thermal emission from cold dust has been observed in the rest-frame FIR spectral energy distribution of z > 5 QSOs
24, 199, 169, 259 �m Herschel maps of J1148 @ z = 6.4
Leipski+13,14
dust continuum observations with ALMA @ 250 GHz
J2310 @ z = 6 J1319 @ z = 6.1 J2054 @ z = 6.03
Wang+13
dust in the early Universe the estimated dust masses are 108 Msun < Mdust < 109 Msun
how are these huge dust masses formed in less than 1 Gyr?
what are the implications for the evolution of the host galaxy?
(Valiante et al. 2009, 2011, 2014; Gall et al. 2010, 2011;
Dwek & Cherchneff 2011; Mattsson 2011; Pipino et al 2011; Calura et al. 2013)
why do the first galaxies care about dust?
metals and dust increase gas cooling: ! affect star formation efficiency ! allow the formation of the first low-mass stars
RS+2003, 2004; Omukai+ 2005;, RS & Omukai 2010; RS+2011,2012;
Chiaki+13,14
stellar sources of dust: SNe observations of SNe and SN remnants show signatures of the
presence of dust associated with the ejecta
Schneider+14
Gall+11, Gomez+12, Dunne+09, Barlow+10, Matsuura+11, Otsuka+10
Crab
CasA
1987A
N49 Bianchi & RS 07 no reverse shock
Bianchi & RS 07 with reverse shock
Todini & Ferrara 01; RS+03, Nozawa+03;Bianchi & RS 07; Cherchneff & Dwek 10; Sarangi & Cherchneff 13; Marassi+14
stellar sources of dust: AGB
Ferrarotti & Gail 01; 02; 06; Zhukovska+08; Nanni+13; Ventura+12a,b; Di Criscienzo+13; Dell’Agli+14; Ventura+14
their role in the early Universe depends on the mass- and metallicity- dependence of the dust yields
• numerical integration of stellar models (ATON code, Ventura+98)
• stationary spherically symmetric wind
• grain growth (olivine, pyroxene, quartz, iron, corundum, silicon carbide, carbon)
Grid of AGB/SAGB stars with 1 Msun ≤ M ≤ 8 Msun and 3x10-4 ≤ Z ≤ 0.008
- Third Dredge Up: surface C enrichment - Hot Bottom Burning: C (and O) surface depletion
dust yields from AGB stars: stellar mass dependence
transition from carbon dust to silicate production at M ~ 3 Msun
Ventura+12a
Ventura+12a Ferrarotti & Gail 06
Ferrarotti & Gail 06
Z = 0.001
HBB HBB
TDU
TDU
dust yields from AGB stars: metallicity dependence
Ventura+12b; Di Criscienzo+13
softer HBB higher Si abundance
" Silicates are produced by > 3 Msun stars
" Silicate dust production increases with Z
" No silicates are produced when Z < 0.001
" Carbon dust is produced by < 3 Msun stars and does not depend on Z
" When Z < 10-4 HBB is present even at M < 2 Msun ! no AGB dust
LMC
dust yields from AGB stars: modelling uncertainties
treatment of mass loss and of convective borders Ventura+13
SMC LMC
Black models: Wachter+08 mass loss; over-shoot (extra-mixing)
extra-mixing
mass loss
Blue models: Blöcker 95 mass loss; no over-shoot (no extra-mixing)
Red models: Blöcker 95 mass loss; over-shoot (extra-mixing)
AGB dust production rates in the Magellanic Clouds
Observed DPRs inferred by different studies
O-AGB include O-rich and anomalous O-rich AGB stars C-AGB include C-rich and extreme AGB stars
AGB dust production rates in the Magellanic Clouds
Theoretical DPRs can be computed as:
stellar IMF dust yield star formation history metal enrichment
Zhukovska & Henning 13 RS+14
AGB dust production rates in the Magellanic Clouds
metallicity – dependent star formation histories (Harris & Zaritsky 2004, 2009)
AGB dust production rates in the Magellanic Clouds
RS+14
age – metallicity relation
Harris & Zaritsky 09
Carrera+08 Piatti 12
Carrera+08 Piatti & Geisler 13
Harris & Zaritsky 04
AGB dust production rates in the Magellanic Clouds
Small Magellanic Cloud Large Magellanic Cloud
Blöcker 95 mass loss Wachter+ 08 mass loss Ferrarotti & Gail 06 models (FG)
Blöcker 95 mass loss
Wachter+ 08 mass loss
RS+14
silicate production at Z ≤ 0.004
FG Z =0.008
silicate production at Z ≤ 0.008
Matsuura+ 09,13
Boyer+ 12
Srinivasan+ 09
Riebel+12
AGB dust production rates in the Magellanic Clouds
Small Magellanic Cloud Large Magellanic Cloud
Blöcker 95 mass loss
Wachter+ 08 mass loss
RS+14
silicate production at Z ≤ 0.004
FG Z =0.008
silicate production at Z ≤ 0.008
" observed DPRs in C-AGBs in the LMC require efficient mass loss (Wachter+ 08)
" observed DPRs in C-AGBs in the SMC require less efficient mass loss (Blöcker 95)
" observed DPRs in O-AGBs in the SMC require silicate dust production at Z ≤ 0.004 as predicted by models with efficient HBB in stars > 3 Msun
Total dust budget in the Magellanic Clouds
Skibba+12 Gordon+14
Skibba+12 Gordon+14
AGB
AGB+SN AGB
AGB+SN
the existing dust mass can have a stellar origin (if no destruction in the ISM occurs) AGB stars make ~ 15% of the total dust budget in the SMC and ~ 70% in the LMC
RS+14
the contribution of AGB stars to early dust enrichment
300 Myr 300 Myr 300 Myr
2%
15% 20% 25% 35%
70%
all stars are formed in a single burst at t = 0 with a Salpeter IMF: AGB dust yields from ATON code (Ventura+12,13) SN yields from Bianchi & Schneider (2007)
with ATON yields, AGB contribution to the total dust budget becomes > 30% only when the Z > 0.004 and
becomes dominant in 500 Myr
when Z ≤ 0.004 AGB dust is always sub-dominant wrt to SN dust
the contribution of AGB stars to early dust enrichment
300 Myr 300 Myr 300 Myr
silicate
silicate silicate
carbon carbon
carbon
2%
15% 20% 25% 35%
70%
all stars are formed in a single burst at t = 0 with a Salpeter IMF: AGB dust yields from ATON code (Ventura+12,13) SN yields from Bianchi & Schneider (2007)
If SN at low Z produce mostly silicate dust, we expect to see only silicate features in young (< 300 Myr) starbursts and the
presence of carbon features may be an indication of the growing AGB contribution to the total dust mass at > 300 Myr
are stellar sources enough to produce ~ 108 Msun of dust in < 1 Gyr?
Valiante et al. 2009, 2011, 2014; Gall et al. 2010, 2011; Dwek & Cherchneff 2011; Mattsson 2011; Pipino et al 2011; Calura et al. 2013
Mdust do not correlate with Mstar Mdust do correlate with MH2
stellar dust is not enough to reproduce the observed Mdust
the observed Mdust require super-solar metallicities and very efficient
grain growth in dense gas
Matsuoka+ 09,11
Valiante et al. 2014
Conclusions
" dust enrichment can be fast, t < 1 Gyr " the presence of dust in the first galaxies triggers the formation of the first low-mass stars at Z < 10-4 Zsun " relative role of SN and AGB stars depends on mass- and Z-dependent AGB yields (in addition to SFH, IMF….) " new AGB dust yields suggest that the contribution of AGB stars can dominate the dust budget at t ~ 300 – 500 Myr when Z > 0.004 " at Z ≤ 0.004 the contribution of AGB stars to dust enrichment depends on the mass loss in the C-star stage #! observations of DPRs in the SMC! " existing dust masses in the SMC, LMC can have a stellar origin but in high-z QSO host galaxies grain growth in the ISM is required