GHOST predicted performance
(dashed red line) against other
current instruments in the field
today. Andy also described the
unique scientific role GHOST will
have in an international context,
from exoplanets to the distant
Universe.
GHOST Progressing Through
Build Phase
The Gemini High-resolution Optical SpecTrograph (GHOST) project continues to progress
through the build phase. When completed,
this instrument will bring long-desired capabilities at a high level of performance to
Gemini South. At the June 2016 conference
of the international society for optics and
photonics (SPIE), held in Edinburgh, Scotland, several GHOST project team members
reported on the project’s status.
Andy Sheinis, Head of Instrumentation at
the Australian Astronomical Observatory
(AAO), which leads the multi-institution
team building GHOST, described the technical advances incorporated into the instrument. GHOST is designed to deliver R =
50,000 and R= 75,000 spectroscopy for up to
two objects simultaneously. GHOST uses a
fiber-based image slicer to allow for a much
smaller spectrograph than that described
by the resolution-slit–width product; it will
also have a sensitivity in the wavelength
range between 363-950 nanometers (nm)
that equals or exceeds that of similar instruments on other world-class facilities. Figure
1 shows the chart that Andy presented at
the SPIE conference, which compares the
October 2016
Figure 1.
GHOST expected
performance
comparison against
other current
instruments in the
field today.
Also presenting at SPIE from
the GHOST project team were
Software Project Manager Peter
Young, Software Engineer Jon
Nielson, and Project Scientist
Mike Ireland — all from the Australian National University. Peter
and Jon presented a paper and poster on
how GHOST will be controlled with software using the Gemini Instrument Application Programmer Interface (GIAPI), the
newest Gemini software framework. Mike’s
paper and poster showed the precision radial velocity error budget for the instrument,
obtained from end-to-end simulations. Although GHOST was not designed for radial
velocity precision, the 10 meters per second
requirement is feasible; GHOST may also
achieve a significantly higher performance
than this.
John Pazder, Project/Optical Engineer at
the National Research Council Canada Herzberg (NRC-H), presented a paper and poster
covering the optical design of the benchmounted spectrograph and the predicted
resolution and efficiency for the spectrograph. The following GHOST project team
members were also in attendance: Project
Manager/Detector Engineer Greg Burley,
from NRC-H; Optics Engineer Ross Zhelem,
from AAO; and Instrument Scientist Steve
Margheim, Systems Engineer Andrew Serio, and Project Manager David Henderson,
from Gemini.
The NRC-H team building the bench-mounted spectrograph subsystem recently re-
GeminiFocus
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