Extremely Large Telescope

Abstract:

We present the results of our subarcsecond resolution interferometric observations of the 1.3 mm CO J = 2-->1 line in the luminous merger NGC 6240. Roughly half of the CO flux is contained in a rotating and highly turbulent thick disk centered between the two radio and near-infrared nuclei. In this disk the molecular gas has velocity widths which reach FWZP line widths of up to 1000 km s(-1). The mass of this gas concentration makes up between 30%-70% of the dynamical mass in this region. NGC 6240 may be in an earlier merging stage than typical ULIRGs such as Arp 220. We compare these results from NGC 6240 with those of other luminous, gas-rich interacting galaxies and mergers.

Abstract:

Near infrared instrumentation at 4 and 8 meter class telescopes has grown rapidly in the past few years with the advent of 1024(2) and 2048(2) detector arrays. We present a brief review of high resolution spectroscopic capabilities available worldwide, with an eye on new developments, e.g. spatially resolved spectroscopy offered by integral field instruments.Observing at near-infrared wavelengths has its own quirks. We discuss observing strategies to get past the limits of high background (including both thermal background and background due to OH sky emission lines), Variations in atmospheric transmission, and detector constraints. Special attention is given to the subject of OH suppression/avoidance, which can significantly increase the sensitivity in the J, EI and short K windows. This is especially important for (fainter) high redshift targets, where the rest frame visible diagnostic lines are shifted into the near infrared.