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Preparatory observations VLT. - VLT-ISAAC survey of ~50 Class I YSO’s. - - Low resolution (R~600) L-band. - Medium resolution (R~10000) M-band. - Other programs. Ewine van Dishoeck c2d meeting dec. 11, 2002. Spectra embedded sources. SIRTF R~600 only at >10 m m => ground-based
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Preparatory observations VLT - VLT-ISAAC survey of ~50 Class I YSO’s --Low resolution (R~600) L-band - Medium resolution (R~10000) M-band - Other programs Ewine van Dishoeck c2d meeting dec. 11, 2002
Spectra embedded sources SIRTF R~600 only at >10 mm => ground-based high resolution in 3-5 mm range Gibb et al. 2000
Ophiuchus sources - Strong solid CO - Gas-phase COin absorption or emission - narrow and broad lines Pontoppidan et al. 2002
Ophiuchus (cont’d) Note fit of all spectra with just 3 components
Orion sources Note shallow absorption at 2175 cm-1: not OCN-
CO gas / solid low-mass YSOs • CO co-exists in gas phase and solid state • Different objects show different ratios of gas:ice, related to their evolution • Observed line profiles provide clues to structure ices by comparison with lab data TPSC78 RE50 VLT-ISAAC large program Pontopidan, et. al., A&A, (2002), in prep
Detection of abundant solid CO in an edge-on circumstellar disk VLT-ISAAC Solid CO VLT-ISAAC K’ Thi, Pontoppidan, vD et al. 2002
Additional data • ESO-TIMMI2 8-13 mm R~200 (with Waters + MPIA-Heidelberg); brightest sources only to check variability • OVRO imaging embedded sources (with Geoff) • VLT-VISIR 8-13 mm, 17-22 mm, R~104; commissioning summer 2003, follow-up bright sources for gas species • JCMT-SCUBA maps of cores (see Neal’s talk)