Time-monitoring observations of the ro-vibrational overtone CO bands in young stars

Abstract

We present near-infrared spectra of a sample of T Tauri, Herbig Ae/Be and FU Ori objects. Using the FSPEC instrument on the Bok 90-inch telescope, we obtained K-band spectra with a resolution of ≈3500. Here, we present spectra of the δv = 2-0 and δv = 3-1 bandheads of ro-vibrational transitions of carbon monoxide. We observed these spectra over multiple epochs spaced by a few days and approximately one month. Several of our targets show CO emission or absorption features. However, we see little evidence of variability in these features across multiple epochs. We compare our results with previous observations and discuss the physical implications of non-variable CO emission across the sampled time-scales. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.