Enhanced Performance for the IMACS F/4 Camera Upgrade

Carnegie Institution Of Washington, Washington DC

Investigators

Abstract

An upgrade is underway for an instrument on the Magellan Baade 6.5-meter telescope at the Carnegie Institution of Washington's Las Campanas Observatory in Chile. The instrument, called IMACS (Inamori-Magellan Arial Camera & Spectrograph) will have the original CCD detectors in its camera replaced with newer technology devices. The new CCDs will provide better throughput, higher signal-to-noise, and increased resolution than the previous chips and will result in significant efficiencies in the use of telescope time. During the process of ordering the new CCDs the Observatory was made aware of a new enhancement to the detectors that would considerably increase the CCDs responsiveness at both the blue and red ends of the observable spectrum. A relatively new CCD technology called "deep-depletion" significantly improves the response at the red end and new anti-reflection coatings can be added to these devices to improve the response in the blue. This combination will add increased science and discovery capability in particular by enabling intermediate resolution (~10,000 <= R <= ~20,000) spectroscopy of the Calcium triplet and Magnesium I lines in the far-red. This capability will be used to study the chemical composition and kinematics of stars in nearby galaxies, the chemical composition of globular clusters in external galaxies, and the chemical composition of dwarf stars in the bulge of our own Milky Way Galaxy. Funds for these enhanced CCDs are being provided through a RAPID grant by NSF's Division of Astronomical Sciences.