CRIRES observations of CO emission from disks around embedded young stars Gregory Herczeg (MPE) Collaborators: Ewine van Dishoeck Klaus Pontoppidan Joanna Brown Jeanette Bast

CRIRES Observations 10 sources: –IRS 43, IRS 44, IRS 63, Elias 23, Elias 29, Elias 32, HH 100, WL 6, WL 12, CrA IRS 2 –Several observed in multiple epochs –Usually a few wavelength settings –Need to add a few more (mostly non- detections) NGS AO not possible –Limited spatial information

Goals: Do young disks emit in CO? –What else is CO probing? –Why do some disks show no CO? Does inner disk structure differ from CTTS disks? – Luminosity – Temperature/Excitation

Red: CRIRES black: ISAAC

IRS 44: resolved emission 0.3 arcsec binary 0.69 mag difference in M Equal brightness in L –(Duchêne et al. 2007) Primary is barely (or not) detected in K, never in J –Ratzka et al. 2005, Terebey et al. 2001, Allen et al CO and H2 emission: only detected from secondary 13CO emission: blueshifted, offset from 12CO emission

H2 S(9) Emission

Variability?

Seeing in Aug.: 0.33 arcsec Seeing in Apr.: 0.56 arcsec Blueshifted CO emission from IRS 44 also variable in EW

Conclusions: CO emission from embedded objects CO absorption can make analysis difficult –Sometimes impossible, sometimes not so bad –Better than H2, which often probes extended material Most emission consistent with a disk origin –Double-peaked profile from Elias 23 –Winds can also play a role (IRS 44) Two components –Narrow, colder, optically-thick –Hot, vibrationally excited broad component TO DO: Add a few sources, temps, luminosities, optical depths