Currently, GRACES is scheduled for on-sky
commissioning in October or December
of this year. Integration and Testing of the
opto-mechanical systems at HIA is planned
for July to September, after which it will
be shipped to Mauna Kea for installation,
daytime testing, and then commissioning.
After that, GRACES will become available
to Gemini’s users in block observing mode
(not queue mode).
Figure 5:
Model rendering of the
injector unit. The optics
are housed in a GMOS-N
filter cassette (large grey
unit). The blue light rays in
the center of the unit are
the two input beams from
Gemini (star and sky),
which reflect off a mirror
to the upper right where
they are fed into two
270-meter-long fibers.
Figure 6:
Model rendering of
the slicer bench. The
ESPaDOnS optical beam
passes though the large
rectangular opening in the
bottom half of the structure.
The top structure houses
the optical fiber inputs,
the optics, adjustment
stages, and the image slicer.
The optical-fiber-cable
attaches through the top
of the assembly where it
passes through the optics
and slicer down to the fold
mirror (grey and brown
piece projecting down
into the bottom half) to be
inserted into ESPaDOnS.
22
hardware parts are being fabricated in the
machine shop at the Dominion Astrophysical Observatory (formerly the Herzberg Institute for Astrophysics).
Figures 5 and 6 show computer-aided design model pictures of the injector unit
(Gemini end) and the slicer unit
(ESPaDOnS end). The injector
unit uses a Gemini North MultiObject Spectrograph (GMOSN) filter cassette, which allows
GMOS-N to act as an acquisition camera for GRACES. Permanently installed in ESPaDOnS,
the slicer includes a deployable
fold mirror that allows ESPaDOnS to be used with the CFHT
or GRACES by simply moving
the fold mirror in and out of the
optical path of ESPaDOnS. Critically, this can be done without
affecting the alignment or performance of either instrument.
Finally, we’ve &V6V