The ELT-MOS (MOSAIC): towards the construction phase

Abstract

When combined with the huge collecting area of the ELT, MOSAIC will be the most effective and flexible Multi-Object Spectrograph (MOS) facility in the world, having both a high multiplex and a multi-Integral Field Unit (Multi-IFU) capability. It will be the fastest way to spectroscopically follow-up the faintest sources, probing the reionisation epoch, as well as evaluating the evolution of the dwarf mass function over most of the age of the Universe. MOSAIC will be world-leading in generating an inventory of both the dark matter (from realistic rotation curves with MOAO fed NIR IFUs) and the cool to warm-hot gas phases in z=3.5 galactic haloes (with visible wavelenth IFUs). Galactic archaeology and the first massive black holes are additional targets for which MOSAIC will also be revolutionary. MOAO and accurate sky subtraction with fibres have now been demonstrated on sky, removing all low Technical Readiness Level (TRL) items from the instrument. A prompt implementation of MOSAIC is feasible, and indeed could increase the robustness and reduce risk on the ELT, since it does not require diffraction limited adaptive optics performance. Science programmes and survey strategies are currently being investigated by the Consortium, which is also hoping to welcome a few new partners in the next two years.

Product assurance for instrumental projects in research laboratory: galaxies, etoiles, physique, instrumentation (GEPI)

“…From the Phase A initial estimates, the full concept will require important hardware budget as well as important FTE 1 for the scientific, management and technical work. Reducing the multiplex to say, e.g., 40% and 80% of the 'full concept' in visible and NIR, respectively, would significantly reduce the hardware costs by about 30% although it would only have a marginal impact on the needed FTEs.…”

“…MOSAIC [1,2] is a Multi Object Spectrograph (MOS) for the Extremely Large Telescope (ELT) of the European Southern Observatory (ESO). The instrument will both use the collecting power and the resolution of the 39m aperture provided by the ELT.…”

Phase A AO system design and performance for MOSAIC at the ELT

“…MOSAIC [1] is a mixed-mode multiple object spectrograph planned for the ELT that has been designed to address the requirements of a broad astronomy user base by covering a large range of potential astronomical science cases [2] . MOSAIC uses a tiled focal plane concept capable of deploying small IFUs directly within the focal plane or pickoff mirrors to feed light into larger IFUs or wave front sensors situated at the field edge.…”