Looking Forward to the
Gemini Infrared Multi-Object
Spectrograph
Figure 6.
The SCORPIO team
— from the Space
Telescope Science
Institute, Southwest
Research Institute,
George Washington
University (GWU),
FRACTAL, and Gemini
Observatory — at the
SCORPIO Quarterly
Progress Meeting at
GWU.
Credit: Alexander van
der Horst
SCORPIO
Under the leadership of Massimo Robberto
(Space Telescope Science Institute) and the
management of Pete Roming (Southwest
Research Institute), Gemini’s next-generation
instrument — the Spectrograph and Camera
for Observations of Rapid Phenomena in the
Infrared and Optical (SCORPIO; formerly OC-
TOCAM) — continues to make solid progress
toward the Critical Design Review. Following
a recent Quarterly Progress Meeting (Figure
6) held at George Washington University in
August, the team are on track to hold the Op-
tical Critical Design Review by the end of No-
vember. On completion, the team will seek
permission to purchase long-lead optical
components for the instrument, including
the collimator and camera optics for each of
the eight channels.
Other areas of the instrument’s design are
progressing well. Recent additional func-
tionality include a mechanized cover, air
purge system, and pupil imager.
The project remains on schedule to complete
the design phase in 2019, delivery in 2021,
and commissioning before the end of 2022.
46
GeminiFocus
The Gemini InfraRed Multi-Object Spectro-
graph (GIRMOS) is a powerful new instru-
ment being built for Gemini by a Canadian
consortium of universities, led by the Uni-
versity of Toronto and the National Research
Council-Herzberg (NRC-Herzberg) Institute
of Astronomy and Astrophysics. This instru-
ment will address a key limitation in existing
adaptive optics (AO) facilities where integral
field spectrographs are only able to observe
single objects with adequate atmospheric
correction, significantly limiting many scien-
tific programs that could be efficiently ob-
served with multiple integral field units.
By taking advantage of the latest develop-
ments in multi-object AO (MOAO) and inte-
gral field spectroscopy, GIRMOS is designed
to have the ability to observe multiple sourc-
es simultaneously at high angular resolution
while obtaining spectra at the same time
(Sivanandam et al., 2018). It accomplishes
this by exploiting the AO correction from
both a telescope-based AO system (either
GeMS or the prospective Gemini North
MCAO system) and its own additional MOAO
system that feeds four 1-2.4 µm integral field
spectrographs (R ~ 3,000 and 8,000) that can
each observe an object independently with-
in a 2 arcminute field of view.
While GeMS is a multi-conjugate AO (MCAO)
system, which applies a global AO correc-
tion over the entire field, the GIRMOS MOAO
strives to optimally correct the observable
field of each individual spectrograph. In gen-
eral, MOAO applies a better correction to
multiple specific spots over a field of view,
while MCAO provides somewhat less correc-
tion uniformly over the entire field of view.
For the multiple-IFUs of GIRMOS, an MOAO
system provides optimal performance with
improved imaging performance along each
integral field spectrograph’s line of sight. This
January 2019 / 2018 Year in Review