At the approach of the new millennium, we find ourselves poised to address fundamental questions about the origin and evolution of the Universe and its contents. The confluence of advances in telescope and spectrograph design, computing power, pathfinding imaging capabilities on the ground and in space, and the maturity of many astrophysical fields, have inspired us to look beyond the study of a few unique objects to the systematic study of large samples in order to characterize their properties, formation and evolutionary history, and cosmological significance. These studies require spectroscopic observations to probe the kinematics, chemical composition, dynamics, ages, masses, and evolutionary histories of astronomical objects.
As a multi-object spectroscopic system, an 8-m SWIFT would deliver more than
an order of magnitude performance over any existing or planned facilities.
Increasing symbol size indicates the system limiting magnitude. Fiber
systems are in italics. The slit density for 8-m SWIFT, Gemini+GMIS and
VLT+VIRMOS are assumed to be comparable.
To meet this challenge, scientists at NOAO have proposed a national facility optimized for efficient multi-object spectroscopy over wide fields. This facility, Spectroscopic Wide-Field Telescope (SWIFT), is conceived as a spectroscopic system with an integrated telescope and spectrograph design that achieves deep (> 25 mag), high throughput, highly multiplexed (2,000-10,000 objects), spectroscopy over a wide field (~1 degree) at optical and near-infrared wavelengths.
We are currently investigating the scientific case and technical feasibility of implementing the SWIFT concept at 8-m and 30-m apertures. Even with an 8-m aperture, SWIFT will provide spectroscopy that is nearly two orders of magnitude more efficient than that provided by extant or planned facilities. The multi-object spectroscopic capability of this facility will allow astronomers to contemplate and complete ground-breaking investigations of a larger scope and more comprehensive nature than have been possible to date. For example, we would be able to answer fundamental questions about the formation of structure in the Universe (e.g., the evolution of large-scale structure, galaxy evolution, and the formation and evolution of the Milky Way) within the next decade.
The wide-field science enabled by SWIFT complements the high angular resolution science targeted by existing 8-m and 10-m designs. In particular, SWIFT fills a need for wide-field multi-object spectroscopy that is driven by our ever increasing ability to carry out deep, large area imaging surveys at X-ray to millimeter wavelengths. In the next few years, facilities on the ground (e.g., NOAO, CFHT, Subaru, VST, VISTA, Magellan, MMT, DMT, ALMA) and in space (e.g., Chandra, XMM, IRIS, SIRTF, GALEX, NGSS) will survey the sky to faint flux levels and correspondingly high source densities (103 - 106 per sq. deg.). Discovering the nature of the detected sources requires the spectroscopic capabilities of SWIFT. In addition, because SWIFT will enable large-scale, comprehensive investigations, archived SWIFT data will have tremendous potential for discovery beyond the intent of the original investigations.
A whitepaper on the scientific case for and the technical feasibility of such a facility is available at http://www.noao.edu/swift. The current version of the whitepaper, which demonstrates that an 8-m SWIFT can be built today with limited technical risk, was presented to the OIR panel of the Decadal Review Panel in June 1999. This document will continue to evolve as we continue to examine the science case, telescope and spectrograph options, and software needs of SWIFT, in particular, when implemented with a 30-m aperture.
We welcome feedback from the community. Please contact any one of us with questions and comments.
Joan Najita, Arjun Dey, George Jacoby,
Sam Barden, Chuck Claver, Charles Harmer