Gemini South’s New Laser
Turns Skyward
Figure 2 (left).
Manuel Maldonado
(FRACTAL Mechanical
Engineer) points to
a design that shows
where light will enter the
OCTOCAM spectrograph.
Figure 3 (right).
Susan Pope (OCTOCAM
Systems Engineer, SwRI)
shows the preliminary
designs of the OCTOCAM
IR detector and mount
(left screen) to Carl
Schwendehman
(Mechanical Engineer, SwRI).
Credit: Andrea Blank
Figure 4 (left).
Gemini South TOPTICA
laser constellation during
the Commissioning Run
on October 26-30, 2017.
tor (PI) for the instrument. This appointment
follows the departure of the Institute de
Astrofísica de Andalucía (IAA) from the proj-
ect. IAA had originally provided the PI and
Deputy Project Manager roles through their
subcontract with SwRI. We regret the depar-
ture and are grateful to IAA for bringing this
project to Gemini.
In mid-December, Morten Andersen (Gemini
Instrument Scientist) and van der Horst met
to progress the Concept of Operations docu-
ment, which describes the instrument’s op-
erating modes and requirements. In January,
2018, the team will come together at a Quar-
terly Review Meeting that will take place at
both FRACTAL — a private technological
company in Madrid, Spain, responsible for
the instrument’s opto-mechanical design
and construction — and The George Wash-
ington University in January, 2018.
The team expects to hold its Preliminary De-
sign Review in Q2 2018.
— Andrea Blank
For four days and nights beginning on Oc-
tober 26th, a team of scientists, observers,
and engineers of the Gemni South Laser Up-
grade project successfully commissioned the
new SodiumStar TOPTICA Phototronics laser
guide star facility (Figures 4 and 5). During
the run, the team validated the new laser’s
performance, comparing it, back to back,
with the old Lockheed Martin Coherent Tech-
nologies laser. The new TOPTICA laser shows
very stable and reliable operation, and gives
excellent sodium return despite being lower
power than the LMCT laser, demonstrating
the effectiveness of the sideband repump-
ing feature of the TOPTICA laser. Direct com-
parison of sodium return from the two lasers
allows a unique experiment comparing so-
dium excitation efficiency between pulsed
(LMCT) and continuous (TOPTICA) lasers,
with results to be presented at the SPIE con-
ference in June.
The new laser was also used during a science
laser run for six nights starting on December
6th; good seeing and a stable laser gave ex-
cellent Gemini Multi-conjugate adaptive op-
tics System (GeMS) performance and stable
adaptive optics (AO) loops.
GeMS instrument Associate Scientist Gaetano
Sivo comments in the observing log: “The per-
formance was unique. The first program we
got diffraction limited in K on several expo-
sures, we can see airy rings just on raw data [59
milliarcseconds (mas)]. All K images got sub-75
mas resolution; we got sub-80 mas in J-band.”
— Manuel Lazo and Paul Hirst
Figure 5 (right).
Gemini South TOPTICA
Laser First Propagation
during the October 2017
Commissioning Run.
Credit (Figures 4 & 5):
Ariel Lopez, GS Science
Operations Specialist
Group Manager
50
GeminiFocus
January 2018 / 2017 Year in Review