Figure 11.
with with cameras that are capable
of reading out frames at a very fast
rate. The images, reduced using spe-
cialized software, allow scientists to
effectively “freeze out” the effects
of atmospheric seeing and perform
the equivalent of space-based imag-
ing with ground-based telescopes.
The design of the
TOPTICA Laser Beam
Injector Interface to the
telescope Beam Transfer
Optics by Gabriel Pérez.
laser is expected to be installed in early Au-
gust, with on-sky commissioning to follow in
the last week of October.
In early May, an initial version of the Ex-
perimental Physics and Industrial Control
System (EPICS) code of the TOPTICA Laser
Interlock System (TLIS) completed success-
ful lab testing testing (Figure 10; previous
page). The TLIS is an important safety system
required to operate the TOPTICA laser at
Gemini South.
Lastly, Gemini Senior Mechanical Group
Leader Gabriel Pérez completed the design
of the interface between the TOPTICA Laser
Head and the Beam Transfer Optics (BTO;
Figure 11), and it is now ready for fabrication.
— Manuel Lazo
‘Alopeke Settles in at
Gemini North
Figure 12.
Members of the ‘Alopeke
team work with Gemini
engineers on Maunakea.
Credit: Joy Pollard
54
In October, Steve Howell and his team (Fig-
ure 12) will plan to commission a
new speckle instrument named
‘Alopeke. The instrument is to be
mounted on the Gemini North
telescope as a Gemini visiting in-
strument. Speckle imaging is an
interferometric technique by which
telescopes can achieve diffraction-
limited imaging performance us-
ing Fourier image reconstruction
techniques techniques (Figure 13)
GeminiFocus
The design of ‘Alopeke is based on
the Differential Speckle Survey In-
strument (DSSI). The original DSSI
has been a popular visiting instru-
ment at Gemini since 2012. Making observa-
tions at both Gemini North and South, DSSI
has provided simultaneous diffraction-limit-
ed optical imaging — Full-Width at Half-Maxi-
mum (FWHM) ~0.02” at 650 nanometers (nm)
— of targets as faint as V ~16–17, in two chan-
nels over a ~2.8” field-of-view. The diffraction-
limited resolution possible at Gemini (0.016”
FWHM at 500 nm or 0.025” at 800 nm), with
no need for an adaptive optics guide star or
laser, offers unique scientific capabilities.
The most recent DSSI visit to Gemini South
was marred slightly by unstable weather,
but in the end, the team obtained data on a
large range of projects from follow-up vali-
dation of exoplanet candidates to a search
for close binary companions of exoplanet
host stars, as well as a study of the rate of bi-
narity in low mass star forming regions.
‘Alopeke is the contemporary Hawaiian
word for Fox, and this name was chosen
January 2018 / 2017 Year in Review