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The spectropolarimeter dimaPol measures circular polarization in spectral lines of stellar objects. The instrument is used to simultaneously detect polarization signals in the hydrogen Hβ line as well as nearby metallic lines. A fast switching ferro-electric liquid crystal waveplate synchronized with charge shuffling on the CCD is employed to greatly reduce instrumental systematics. dimaPol has been in use on the DAO 1.8-m Plaskett telescope since 2007. In this presentation we show the capabilities of the instrument as well as some of the main results obtained with it to date., Series: Proceedings of the International Astronomical Union

The Gemini Planet Imager (GPI) is a facility extreme-AO high-contrast instrument – optimized solely for study of faint companions – on the Gemini telescope. It combines a high-order MEMS AO system (1493 active actuators), an apodized pupil Lyot coronagraph, a high-accuracy IR post-coronagraph wavefront sensor, and a near-infrared integral field spectrograph. GPI incorporates several other novel features such as ultra-high quality optics, a spatially-filtered wavefront sensor, and new calibration techniques. GPI had first light in November 2013. This paper presnets results of first-light and performance verification and optimization and shows early science results including extrasolar planet spectra and polarimetric detection of the HR4696A disk. GPI is now achieving contrasts approaching 10-6 at 0.5” in 30 minute exposures.

The Gemini Planet Imager (GPI) entered on-sky commissioning and had its first-light at the Gemini South (GS) telescope in November 2013. GPI is an extreme adaptive optics (XAO), high-contrast imager and integral-field spectrograph dedicated to the direct detection of hot exo-planets down to a Jupiter mass. The performance of the apodized pupil Lyot coronagraph depends critically upon the residual wavefront error (design goal of 60nmRMS with, Adaptive Optics Systems IV, June 22-27, 2014, Series: Proceedings of SPIE; no. 9148

An Atmospheric Dispersion Corrector (ADC) uses a double-prism arrangement to nullify the vertical chromatic dispersion introduced by the atmosphere at non-zero zenith distances. The ADC installed in the Gemini Planet Imager (GPI) was first tested in August 2012 while the instrument was in the laboratory. GPI was installed at the Gemini South telescope in August 2013 and first light occurred later that year on November 11th. In this paper, we give an overview of the characterizations and performance of this ADC unit obtained in the laboratory and on sky, as well as the structure of its control software., Comment: 16 pages, 12 figures. Proceedings of the SPIE, 9147-183

We present performance results, from in-lab testing, of the Integral Field Spectrograph (IFS) for the Gemini Planet Imager (GPI). GPI is a facility class instrument for the Gemini Observatory with the primary goal of directly detecting young Jovian planets. The GPI IFS is based on concepts from the OSIRIS instrument at Keck and utilizes an infrared transmissive lenslet array to sample a rectangular 2.8 x 2.8 arcsecond field of view. The IFS provides low-resolution spectra across five bands between 1 and 2.5 μm. Alternatively, the dispersing element can be replaced with a Wollaston prism to provide broadband polarimetry across the same five filter bands. The IFS construction was based at the University of California, Los Angeles in collaboration with the Université de Montréal, Immervision and Lawrence Livermore National Laboratory. During its construction, we encountered an unusual noise source from microphonic pickup by the Hawaii-2RG detector. We describe this noise and how we eliminated it through vibration isolation. The IFS has passed its preship review and was shipped to University of California, Santa Cruz at the end of 2011 for integration with the remaining sub-systems of GPI. The IFS has been integrated with the rest of GPI and is delivering high quality spectral datacubes of GPI's coronagraphic field., Ground-Based and Airborne Instrumentation for Astronomy IV, July 1-6, 2012, Amsterdam, Netherlands, Series: Proceedings of SPIE

Small deformable mirrors (DMs) produced using microelectromechanical systems (MEMS) techniques have been used in thermally stable, bench-top laboratory environments. With advances in MEMS DM technology, a variety of field applications are becoming more common, such as the Gemini Planet Imager's (GPI) adaptive optics system. Instruments at the Gemini Observatory operate in conditions where fluctuating ambient temperature, varying gravity orientations and humidity and dust can have a significant effect on DM performance. As such, it is crucial that the mechanical design of the MEMS DM mount be tailored to the environment. GPI's approach has been to mount a 4096 actuator MEMS DM, developed by Boston Micromachines Corporation, using high performance optical mounting techniques rather than a typical laboratory set-up. Flexures are incorporated into the DM mount to reduce deformations on the optical surface due to thermal fluctuations. These flexures have also been sized to maintain alignment under varying gravity vector orientations. This paper is a follow-up to a previous paper which presented the preliminary design. The completed design of the opto-mechanical mounting scheme is discussed and results from finite element analysis are presented, including predicting the stability of the mirror surface in varying gravity vectors and thermal conditions. © 2012 SPIE., Modern Technologies in Space- and Ground-Based Telescopes and Instrumentation II, July 1-6, 2012, Amsterdam, The Netherlands, Series: Proceedings of SPIE; no. 8450

This paper presents an overview of the PDR level mechanical and opto-mechanical design of the cryogenic spectrograph unit of the nIR spectropolarimeter (SPIROU) proposed as a new-generation instrument for CFHT. The design is driven by the need for high thermo-mechanical stability in terms of the radial velocity (RV) of 1 m/s during one night, with the requirement for thermal stability set at 1 mK/24 hours. This paper describes stress-free design of the cryogenic optical mounts, mechanical design of the custom-build cryostat, mechanical design of the optical bench, and thermal design for 1 mK thermal stability. The thermal budget was calculated using lumped-mass model thermal analysis, implemented in Modelica multi-domain modeling language. Discussion of thermal control options to achieve 1 mK thermal stability is included. © 2012 SPIE., Ground-Based and Airborne Instrumentation for Astronomy IV, July 1-6, 2012, Amsterdam, The Netherlands, Series: Proceedings of SPIE; no. 8446

The Gemini Planet Imager (GPI) is an extreme AO coronagraphic integral field unit YJHK spectrograph destined for first light on the 8m Gemini South telescope in 2011. GPI fields a 1500 channel AO system feeding an apodized pupil Lyot coronagraph, and a nIR non-common-path slow wavefront sensor. It targets detection and characterizion of relatively young (

The Gemini Planet Imager (GPI) is a new facility instrument to be commissioned at the 8-m Gemini South telescope in early 2011. It combines of several subsystems including a 1500 subaperture Extreme Adaptive Optics system, an Apodized Pupil Lyot Coronagraph, a near-infrared high-accuracy interferometric wavefront sensor, and an Integral Field Unit Spectrograph, which serves as the science instrument. GPI's main scientific goal is to detect and characterize relatively young ( 5λ/D, without active wavefront control (no deformable mirror). We use Fresnel propagation modeling to analyze the testbed results.

The Gemini Planet Imager (GPI) is a facility instrument under construction for the 8-m Gemini South telescope. It combines a 1500 subaperture AO system using a MEMS deformable mirror, an apodized-pupil Lyot coronagraph, a high-accuracy IR interferometer calibration system, and a near-infrared integral field spectrograph to allow detection and characterization of self-luminous extrasolar planets at planet/star contrast ratios of 10-7. I will discuss the evolution from science requirements through modeling to the final detailed design, provide an overview of the subsystems and show models of the instrument's predicted performance.