Mr. Jeff Donahue Profile

Jeff Donahue

Lead Senior Laser Technician at Gemini Observatory

SPIE Involvement:

Author

Publications (4)

Proceedings Article | 10 July 2018 Presentation + Paper

An infusion of new blood using the Toptica laser with GeMS: results of the commissioning and science performance

Gaetano Sivo, Eduardo Marin, François Rigaut, Marcos van Dam, Vincent Garrel, Benoit Neichel, Cristian Moreno, Emmanuel Chirre, Constanza Araujo, Allen Hankla, Gabriel Perez, Pablo Diaz, Angelic Ebbers, Paul Collins, Vicente Vergara, Paul Hirst, Morten Andersen, Joy Chavez, Lindsay Magill, Christine Cunningham, Ariel Lopez, Jeff Donahue, Rodrigo Carrasco, Gianluca Lombardi, Vanessa Montes, Michiel van der Hoeven, René Rutten, Scot Kleinman, Manuel Lazo

Proceedings Volume 10703, 107030P (2018) https://doi.org/10.1117/12.2312090

KEYWORDS: Adaptive optics, Gemini Observatory, Laser systems engineering, Laser guide stars, Sodium, Telescopes, K band, Photometry

Read Abstract +

Proceedings Article | 4 October 2016 Paper

Real-time implementation of an LQG tip-tilt controller for regular science observation on GeMS

Gaetano Sivo, Rémy Juvénal, Caroline Kulcsár, Vincent Garrel, Pedro Gigoux, Henri-François Raynaud, Eduardo Marin, Jean-Marc Conan, Cyril Petit, William Rambold, Vanessa Montes, Cristian Moreno, Jeff Donahue, Rodrigo Carrasco, Marcos van Dam, Benoît Neichel, Lucie Leboulleux, Chad Trujillo

Proceedings Volume 9909, 99094Y (2016) https://doi.org/10.1117/12.2233191

KEYWORDS: Atmospheric optics, Gemini Observatory, Gemini Planet Imager, Adaptive optics, Telescopes, Device simulation, Data modeling, Autoregressive models, Real-time computing, Matrices

Read Abstract +

Proceedings Article | 27 July 2016 Paper

Reshaping and polishing the GeMS MCAO system

Vincent Garrel, Gaetano Sivo, Eduardo Marin, Eleazar Carrasco Damele, Vanessa Montes, Manuel Lazo, Pedro Gigoux, Cristian Moreno, Chadwick Trujillo, Jeff Donahue, Marcos van Dam, Francois Rigaut, Céline d'Orgeville, Caroline Kulcsar, Remy Juvénal, Constanza Araujo Hauck, S. Mark Ammons, Benoit Neichel

Proceedings Volume 9909, 99092F (2016) https://doi.org/10.1117/12.2233747

KEYWORDS: Polishing, Gemini Observatory, Near infrared, Wavefront sensors, Calibration, Adaptive optics, Telescopes, Stars, Point spread functions, Super resolution

Read Abstract +

Proceedings Article | 7 August 2014 Paper

Life with quintuplets: transitioning GeMS into regular operations

Vincent Garrel, Marcos Van Dam, Benoît Neichel, Fabrice Vidal, Gaetano Sivo, Eduardo Marin, Vanessa Montes, Andrew Serio, Gustavo Arriagada, Chadwick Trujillo, William Rambold, Pedro Gigoux, Ramon Galvez, Cristian Moreno, Constanza Araujo Hauck, Tomislav Vucina Parga, Jeff Donahue, Claudio Marchant, Gaston Gausachs, Fabian Collao, Eleazar Carrasco Damele, Peter Pessev, Ariel Lopez

Proceedings Volume 9148, 914829 (2014) https://doi.org/10.1117/12.2056378

KEYWORDS: Adaptive optics, Stars, Gemini Observatory, Telescopes, Wavefront sensors, Electroluminescent displays, Laser guide stars, Actuators, K band, Software development

Read Abstract +

The Gemini Multi-conjugate adaptive optics System (GeMS) at the Gemini South telescope in Cerro Pachon is the first sodium Laser Guide Star (LGS) adaptive optics (AO) system with multiple guide stars. It uses five LGSs and two deformable mirrors (DMs) to measure and compensate for distortions induced by atmospheric turbulence. After its 2012 commissioning phase, it is now transitioning into regular operations. Although GeMS has unique scientific capabilities, it remains a challenging instrument to maintain, operate and upgrade. In this paper, we summarize the latest news and results. First, we describe the engineering work done this past year, mostly during our last instrument shutdown in 2013 austral winter, covering many subsystems: an erroneous reconjugation of the Laser guide star wavefront sensor, the correction of focus field distortion for the natural guide star wavefront sensor and engineering changes dealing with our laser and its beam transfer optics. We also describe our revamped software, developed to integrate the instrument into the Gemini operational model, and the new optimization procedures aiming to reduce GeMS time overheads. Significant software improvements were achieved on the acquisition of natural guide stars by our natural guide star wavefront sensor, on the automation of tip-tilt and higher-order loop optimization, and on the tomographic non-common path aberration compensation. We then go through the current operational scheme and present the plan for the next years. We offered 38 nights in our last semester. We review the current system efficiency in term of raw performance, completed programs and time overheads. We also present our current efforts to merge GeMS into the Gemini base facility project, where night operations are all reliably driven from our La Serena headquarter, without the need for any spotter. Finally we present the plan for the future upgrades, mostly dedicated toward improving the performance and reliability of the system. Our first upgrade called NGS2, a project lead by the Australian National University, based a focal plane camera will replace the current low throughput natural guide wavefront sensor. On a longer term, we are also planning the (re-)integration of our third deformable mirror, lost during the early phase of commissioning. Early plans to improve the reliability of our laser will be presented.

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years