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MAGiC IV : 星間物質の基本平面. Shinya Komugi NAOJ Chile Observatory + Rie Miura, Sachiko Onodera, Tomoka Tosaki, Nario Kuno + many (NRO Legacy MAGiC team, ASTE team, AzTEC team). NRO UM Jul. 25 2013. Star formation relation within M33. Increased scatter at 100pc scale Effect of GMC evolution ?
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MAGiC IV : 星間物質の基本平面 Shinya Komugi NAOJ Chile Observatory + Rie Miura, Sachiko Onodera, Tomoka Tosaki, Nario Kuno + many (NRO Legacy MAGiC team, ASTE team, AzTEC team) NRO UM Jul. 25 2013
Star formation relation within M33 Increased scatter at 100pc scale Effect of GMC evolution ? (e.g., Kawamura et al. 2009, Onodera et al. 2010) Onodera et al. 2010
Star formation relation within Taffy I (Komugi+ 2012) J=blue、H=green、Ks=red ・All but 1 SF region are 7Myr old ・gas=CO@OVRO, sfr=Paα@TAO log SFR=0.95 logΣvar(H2)-8.23 ・small dispersion @ 700pc σ= 0.1 for varying Xco c.f. σ = 0.5 in M51 (Liu+11) GMCs (SF regions) at a similar Evolution stage give tight SK laws
The ISM at GMC scales emissivity Dust temperature metallicity 1.1 mm heating Gas/dust ratio Opt.-Near IR Xco Interstellar Radiation Field Molecular gas (CO) extinction 12CO(J=1-0) 2.1 um “Dense” gas Star formation 12CO(J=3-2) UV input K-S law Hα, 24um + time evolution IMF
Interaction of ISM at 100pc in M33 12CO(J=1-0) @ NRO 45m Tosaki et al. (2011) Catalog in progress
Interaction of ISM at 100pc in M33 12CO(J=3-2) map @ASTE Miura et al. (2012) 71 GMCs catalogued Lco, rmaj, rmin, σv, Tmb Radius range 20 ~ 40
Interaction of ISM at 100pc in M33 1.1mm and dust temperature map ASTE and Spitzer 160um Komugi et al. (2011)
Interaction of ISM at 100pc in M33 57 GMCs at ~100pc resolution with 12CO(J=1-0) M10 : total molecular gas 12CO(J=3-2) M32 : dense molecular gas 1.1mm Mdust : dust mass (using Tcold map and β=2) Ks band K : measure of ISRF from old stellar pop. Hα, 24um SFR : star formation rate (UV photon) Type B, C, D : evolutionary stage
・ PC4 and PC5 have smallest variance, i.e. we can write PC4 = 0 PC5 = 0 ・ SFR, K, Md contains 99.3% of the information in PC4 0.72 logSFR + 0.29 logK - 0.62 logMd = 0 ± 0.43 logSFR = (2.4 ± 0.3) logMdust – (0.23 ± 0.06) Kmag. + 0.15 ± 1.2 scatter = 0.4 dex ・ SFR, M CO10, MCO32 contains 99.6% of the information in PC5 0.75 logMCO32 - 0.64 logMCO10 - 0.14 logSFR = 0 ± 0.29 logM32 = (0.86 ± 0.06) logM10 + (0.12 ± 0.02) logSFR + 1.0 ± 0.02 scatter = 0.1 dex
PC5 : SFR-MCO32-MCO10 plane log MCO32 (M◉ pc-2) log MCO10 (M◉ pc-2) log SFR (M◉ yr-1 pc-2)
PC5 : SFR-MCO32-MCO10 plane • 3D version of SK law, but strongest correlation is between CO32 and CO10. • SK law at 100 pc is better expressed as “CO32/CO10 ratio is modulated by SFR” • Consistent with “dense gas fraction is larger for clouds with more active SF” (Onodera+ 2012)
PC4 : SFR-Mdust-KS plane log Mdust (M◉ pc-2) ISRF (K band mag.) log SFR (M◉ yr-1 pc-2)
PC4 : SFR-Mdust- KS plane • SFR-Mdust tighter than SFR-MCO32 or SFR-MCO10 Dust traces molecular gas better ?? • GMC evolution = movement in the plane; young GMC 2um dark, less dust, small SFR < 10Myr GMC 2um bright, range of dust and SFR > 10Myr GMC intermediate in SFR, dust, 2um.
summary • Multi-parameter analysis of GMC in M33 • 2 most fundamental relations ; “Classical” KS law can be explained by combining these • PCA can be a powerful tool to interpret the entangled relations in the ISM • Needs verification in other galaxies 12CO + Paα survey of NGC300 ongoing logSFR = (2.4 ± 0.3) logMd – (0.23 ± 0.06) Kmag. + 0.15 ± 1.2 scatter = 0.4 dex logMCO32 = (0.86 ± 0.06) logMCO10 + (0.12 ± 0.02) logSFR + 1.0 ± 0.02 scatter = 0.1 dex