GeminiFocus January 2018 - Page 16

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 Schwend ehman (Mechanical Engineer, SwRI). Credit: Andrea Blank Figure 4 (left). 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. The team expects to hold its Preliminary De- sign Review in Q2 2018. — Andrea Blank Gemini South TOPTICA laser constellation during the Commissioning Run on Oct 26-30, 2017. 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. During the run, the team validated the new laser’s performance, com- paring it, back to back, with the old Lockheed Martin Coherent Technologies 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 repumping feature of the TOPTICA laser. Direct comparison of sodium return from the two lasers allows a unique experi- ment comparing sodium excitation efficien- cy between pulsed (LMCT) and continuous (TOPTICA) lasers, with results to be present- ed at the SPIE conference in June. The new TOPTICA laser was used during the next science laser run for six nights starting on December 6 th — good seeing and a stable laser gave excellent Gemini Multi-conjugate adaptive optics 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 14 GeminiFocus January 2018