Time-monitoring Observations of the Ro-Vibrational Overtone CO bands in Young Stars

TL;DR

This study presents near-infrared spectra of young stars focusing on CO bands, observing their features over time to understand variability and physical conditions in their circumstellar environments.

Contribution

First multi-epoch near-IR spectroscopic observations of CO ro-vibrational bands in young stars, analyzing their variability and physical implications.

Findings

Most targets show CO emission or absorption features.

Little evidence of variability in CO features over days to a month.

Results suggest stable physical conditions in the CO-emitting regions.

Abstract

We present near-IR 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 v=2->0 and v=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 timescales.