The first choice to achieve our scientific goals of a wide field 8m telescope is to work within the existing CFHT partnership, roughly along the lines of the plans recently prepared by J. Espiard and W. Grundmann, as displayed on our frontispiece.
The CFHT partners have been vigorously yet carefully examining the Telescope's future in the near- and long-terms through the Scientific Advisory Committee (SAC), the Next Generation CFHT Committee, the Board, as well as through national committees and planning exercises. Our proposal builds upon these studies in important ways.
Why now? Why through CFHT?
- The CFHT partnership is extraordinarily successful in terms of the quality and impact of the science produced with its jointly developed, state-of-the-art instrumentation.
- The site is one of the very best in the world in terms of intrinsic image quality, which carries a special responsibility to ensure that it continues to be used optimally.
- The VLOT envisioned by the NGC as the long-term facility required by the partnership will only become available late in the second decade of the 21st century. After submission of the NGC report, it became clear that a telescope the size of VLOT cannot be built on the CFHT site - or on the visible ridge of Mauna Kea - because of sensitivities within the State of Hawaii and limitations on physical space.
- The science we propose is designed for a wide field 8m telescope delivering images that fully exploit the unique qualities of the CFHT site. No other 8m class telescope will have the field of view of this telescope, which is crucial for assembling statistically reliable samples; a wide array of the key astronomical questions of the next decade and beyond can be answered with this telescope on the CFHT site.
- It will complement proposed major new facilities such as NGST, LMA and VLOT and ensure Canadian leadership roles in them.
- This telescope can be implemented quickly and in a cost effective fashion through the use of proven designs.
- A rapid replacement of CFHT greatly extends the scientific payoff from the partner's 25 years of investments, including in the new MegaCam imager. As a bonus, the power of the existing coude laboratory with fibre fed instruments like Gecko, the superb R=120,000 spectrograph, and visitor instruments like ESPADONS, is greatly amplified and extended.
- The use of an existing design means that the construction cost and time estimates have minimal risk.
- The new facility becomes more cost effective as a result of replacement of CFHT's dated design and aging components with the engineering advances reflected in modern 8m telescopes.
- With a small, stable, excellent instrument complement, operating costs will be minimized and a large fraction of them could be met by the existing annual operating budget of CFHT.
- Detectors operating in the important near-infrared part of the spectrum are now becoming of high quality and readily available.
Thus, what is an urgent necessity for continued Canadian astronomical excellence is equally beneficial to the CFHT partners and we propose exploring every possible way to bring our plan to fruition with them.
Our proposal complements the long-term vision elaborated in the NGC report and prepares the path to ensure that Canadians will be scientifically ready to lead in the development of the world's VLOT observatory, the engineering studies for which need to be carried out in the coming decade for implementation toward the end of the second decade of the 21st century.
The front-line lifetime of modern telescopes appears to be at least twenty years. Integrated operating costs generally exceed the capital expenditure. One could then infer that a delay of five years is not serious. But no scientific case can be made that it would be undesirable to replace the aging CFHT 3.6 m as soon as possible with a modern 8m instrument, with some twelve months of down-time.We note that the existing 3.6 meter CFHT already has a need to schedule considerable downtime to implement Megaprime and undertake a dome image quality improvement program.
Furthermore, part of the power of the proposed facility is to be in place prior to the arrival of the LMA and NGST. This is particularly important for the Canadian community where new faculty and PDFs are building their careers over the next decade. It would be most detrimental if our late arrival with an 8m, as powerful as this one is, limited our ability to respond competitively to such opportunities as the LMA, NGST and VLOT. Therefore, we cannot support a plan which calls for no action for five years.
We are also aware that there is a possibility that an 8 meter could be designed to explore a critical path of technology for a future VLOT. From a scientific point of view, however, we feel that the fastest possible replacement is the preferred strategy, and that VLOT technology be developed in other ways.