Future Millimeter/Submillimeter Instrumentation and Science Opportunities: The Example of Deuterated Molecules

Studies of the physics and chemistry of the dense interstellar medium have developed mostly through observations of the millimeter and submillimeter bands. The initial ground-based facilities have been single dishes in the 3-30m class. Mostly, these telescopes have been equipped with SIS receivers and small bolometer arrays. The frequency range is limited to about 300 GHz, with a few dishes extending to 900 GHz. Also the Kuiper Airborne Observatory (KAO), with a 0.9m telescope, provided a limited view at frequencies not available from the ground. To this capability have been added the interferometers (BIMA, OVRO, IRAM, and more recently SMA), providing much better angular resolution and improved detectivity.

However, none of the existing facilities represents the investment of the class of HST, VLT, Keck, Gemini etc., available to optical astronomy, or the VLA, VLBA etc., to radio. Obtaining instrumentation, commensurate with the needs of the science, has been a goal since about 1980 and now that goal is being met. ALMA, the ultimate ground-based interferometer, LMT, a 50m single dish, SOFIA, the replacement for the KAO and Herschel, a submillimeter/far-infrared space observatory, are being built. Also, new types of receivers and bolometer arrays are being planned and constructed.

This talk will attempt to describe the new capabilities and some aspects of what might be achieved with them in terms of the ISM.