Phase I

The objective of Phase I is to demonstrate beam extraction from each focal plane and injection into a single mode fiber, and to transport the beam through the fiber from each telescope to its base (i.e. a fixed point on the ground).

Due to the AO capability of beam steering, a simple optical module ensures the feeding into the fiber, providing useful feedback to the observatories in terms of temporal image stability, and vibration feedback, through measurements of coupling efficiency and stability (Coudé du Foresto, 2000 [6]).

The beam transport from the telescope to its base must take into account possible bending and twisting of the fiber (with possible impact on the polarization, if non-polarization maintaining fibers are used). This could also provide feedback to the observatories interested in performing polarimetry.

Funding for Phase I has been in parts secured through proposals to the Paris Observatory and the ATI (Action Thématique Innovante) from CNRS. This will be put to use in the following:

• The construction of a prototype beam extractor and its test on the sky to measure injection efficiency and stability with AO.
• The evaluation and measurement of routing, bending and twisting impacts on fiber behavior for the various telescope configurations (Cassegrain, equatorial and alt-az, and Nasmyth on alt-az).
• The design of phase II: science programs, detailed instrumental plan and costing.

A student, Julien Woillez, from the Ecole doctorale de Paris (Graduate school in astronomy) started his PhD for the realization of Phase I, and is visiting Hawaii between October and December 2000. The goal of this visit is to allow familiarization with the AO systems and the local partners, and conceptual design of the extractor.

A second meeting will be held at CFHT headquarters on December 18^th and 19^th 2000 to address some of the technical issues related to the implementation of Phase I, the design of phase II and to start working groups on the scientific applications of `Ohana.