preparatory observations vlt - vlt-isaac survey of ~50 class i yso’s -- low resolution (r~600)...
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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
Spectra embedded sources
Gibb et al. 2000
SIRTF R~600 only at >10 m => ground-basedhigh resolution in 3-5 m range
Ophiuchus sources
- Strong solid CO
- Gas-phase CO inabsorption or
emission
- narrow and
broad lines
Pontoppidan et al. 2002
Ophiuchus (cont’d)
Note fit of all spectra with just 3 components
Serpens sources
Orion sources
Note shallow absorption at 2175 cm-1: not OCN-
R CrA sources
Chamaeleon sources
Vela sources/L1489 in Taurus
CO gas / solid low-mass YSOsCO gas / solid low-mass YSOs
RE50
TPSC78
• 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
Pontopidan, et. al., A&A, (2002), in prep VLT-ISAAC large program
Detection of abundant solid CO in an edge-on circumstellar disk
VLT-ISAAC K’
VLT-ISAAC
Thi, Pontoppidan, vD et al. 2002
Solid CO
Additional data
• ESO-TIMMI2 8-13 m R~200 (with Waters + MPIA-Heidelberg); brightest sources only to check variability
• OVRO imaging embedded sources (with Geoff)• VLT-VISIR 8-13 m, 17-22 m, R~104;
commissioning summer 2003, follow-up bright sources for gas species
• JCMT-SCUBA maps of cores (see Neal’s talk)
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