Gemini On-Going Instrument Program

In order to ensure the continuing relevance of the Gemini Future Instrumentation Program, international scientific workshops will be held every few years. This will provide our partnership an opportunity to reevaluate the content and direction of the instrumentation program from a scientific and technical perspective, taking into account changing scientific opportunities and the evolution of technology. The first of these international workshops was held in Abingdon UK in January 1997 (see the online workshop report).

This Workshop addressed four broad areas: 1) Stars and Planetary Systems; 2) Star Formation and the Interstellar Medium; 3) Galactic Structure and Nearby Galaxies; and 4) Formation and Evolution of Galaxies and Cosmology. The goal was to identify the key instrumentation capabilities based on illustrative problems from these broad areas to ensure that Gemini would enable observations addressing these as well as many other scientific opportunities.

Two broad perspectives emerged from the workshop discussions as the basis for future instrumentation for the Gemini telescopes. The first is the ability to obtain near diffraction-limited imaging capabilities at near IR wavelengths, on both Gemini telescopes. The implementation of adaptive optics (AO) was considered of paramount importance to effectively address key scientific issues over the whole range of topics. Recent advances demonstrating the scientific utility of AO and of Laser Guide Star (LGS) capabilities have highlighted the timeliness of this capability. Gemini's priority is to use LGS AO technologies to maximize sky coverage. With this capability, the Gemini telescopes will complement and extend HST performance at Near-IR wavelengths, and will provide spatial and spectral resolution capabilities in the 2-20µm atmospheric windows far superior to the capabilities of ISO and those planned for SIRTF.

The second perspective focused on technological advances in Near-IR arrays that enable new innovative instrumentation capabilities that will fully exploit the images delivered by the Gemini telescopes at wavelengths longward of one micron. The development of high performance 1kx1k and 2kx2k Near IR arrays, leading possibly to 4kx4k focal planes, open new possibilities for addressing many key scientific issues using Integral Field Units (IFU), multislit, and multi object spectroscopic capabilities at Near IR wavelengths.

New Instrumentation Capabilities

The mapping of science programs onto instrumentation capability is summarized in the table below and illustrates the broad use of these capabilities among the different scientific areas. These perspectives and the scientific discussions led to the identification of the following components of the future Gemini instrumentation capability:

• A Natural Guide Star/Laser Beacon Adaptive Optics system (AOS) at Cerro Pachon, and LGS capability for the Mauna Kea AO system
• A Near IR Coronagraph/Imager at Cerro Pachon
• 1 - 2.5µm Multi-object spectroscopic (MOS) capability, including IFU and multi-slit capability for use with AO corrected images, and wide field multi-object capability over at least 5 arcmin field of view.
• Polarization modulators for Optical and IR wavelengths at both Mauna Kea and Cerro Pachon
• A High Stability Lab Optical Spectrometer for Cerro Pachon, with resolutions around 120K and >300K.

In the appropriate sections, each of these instrument capabilities is briefly discussed, including illustrations of scientific drivers and Performance Guidelines established for the capability. The Performance Guidelines are intended to provide guidance for conceptual design activities, and it is anticipated that modifications and extensions to the Performance guidelines will occur during and at the end the conceptual design activity as the technical issues, opportunities and cost tradeoffs become better understood. Performance requirements will be established prior to the start of the completion phase of each instrument.

Last update October 27, 1998; Phil Puxley