MMTF: The Maryland-Magellan Tunable Filter

TL;DR

The paper introduces the Maryland-Magellan Tunable Filter (MMTF), a versatile instrument on the Magellan telescope that offers adjustable wavelength filtering for detailed astronomical imaging and spectroscopy.

Contribution

It provides a comprehensive description of MMTF's hardware, software, and observing techniques, highlighting its capabilities and lessons learned from three years of use.

Findings

Achieved ~0.5" image quality over a 27' field of view

Demonstrated versatile use in various astronomical projects

Provided detailed data reduction techniques for tunable filter observations

Abstract

This paper describes the Maryland-Magellan Tunable Filter (MMTF) on the Magellan-Baade 6.5-meter telescope. MMTF is based on a 150-mm clear aperture Fabry-Perot (FP) etalon that operates in low orders and provides transmission bandpass and central wavelength adjustable from ~5 to ~15 A and from ~5000 to over ~9200 A, respectively. It is installed in the Inamori Magellan Areal Camera and Spectrograph (IMACS) and delivers an image quality of ~0.5" over a field of view of 27' in diameter (monochromatic over ~10'). This versatile and easy-to-operate instrument has been used over the past three years for a wide variety of projects. This paper first reviews the basic principles of FP tunable filters, then provides a detailed description of the hardware and software associated with MMTF and the techniques developed to observe with this instrument and reduce the data. The main lessons learned in the course of the commissioning and implementation of MMTF are highlighted next, before concluding with a brief outlook on the future of MMTF and of similar facilities which are soon coming on line.