The Spectrum of the Th-Ar Hollow-Cathode Lamp Used with the 2dcoude Spectrograph
Abstract
We have produced an atlas of the Th-Ar hollow-cathode lamp used with the 2dcoude spectrograph at McDonald Observatory. The atlas covers from 3611.9 to 10596.4 A at a resolving power of 52,000. We have determined the wavelenghts of 1483 emission lines in the spectrum with a median precision of 0.00023 A. A web-based interface is offered for interactive visualization of segments of the atlas or spectral orders.