Gemini Infrared Multi-Object Spectrograph: Instrument Overview
  The Gemini Infrared Multi-Object Spectrograph (GIRMOS) is a powerful new
instrument being built to facility-class standards for the Gemini telescope. It
takes advantage of the latest developments in adaptive optics and integral
field spectrographs. GIRMOS will carry out simultaneous
high-angular-resolution, spatially-resolved infrared ($1-2.4$ $\mu$m)
spectroscopy of four objects within a two-arcminute field-of-regard by taking
advantage of multi-object adaptive optics. This capability does not currently
exist anywhere in the world and therefore offers significant scientific gains
over a very broad range of topics in astronomical research. For example,
current programs for high redshift galaxies are pushing the limits of what is
possible with infrared spectroscopy at $8-10$-meter class facilities by
requiring up to several nights of observing time per target. Therefore, the
observation of multiple objects simultaneously with adaptive optics is
absolutely necessary to make effective use of telescope time and obtain
statistically significant samples for high redshift science. With an expected
commissioning date of 2023, GIRMOS's capabilities will also make it a key
followup instrument for the James Webb Space Telescope when it is launched in
2021, as well as a true scientific and technical pathfinder for future Thirty
Meter Telescope (TMT) multi-object spectroscopic instrumentation. In this
paper, we will present an overview of this instrument's capabilities and
overall architecture. We also highlight how this instrument lays the ground
work for a future TMT early-light instrument.
