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Since 1st light in 2002, HARPS has been setting the standard in the exo-planet detection by radial velocity (RV) measurements[1]. Based on this experience, our consortium is developing a high accuracy near-infrared RV spectrograph covering YJH bands to detect and characterize low-mass planets in the habitable zone of M dwarfs. It will allow RV measurements at the 1-m/s level and will look for habitable planets around M- type stars by following up the candidates found by the upcoming space missions TESS, CHEOPS and later PLATO. NIRPS and HARPS, working simultaneously on the ESO 3.6m are bound to become a single powerful high-resolution, high-fidelity spectrograph covering from 0.4 to 1.8 micron. NIRPS will complement HARPS in validating earth-like planets found around G and K-type stars whose signal is at the same order of magnitude than the stellar noise. Because at equal resolving power the overall dimensions of a spectrograph vary linearly with the input beam etendue, spectrograph designed for seeing-limited observations are large and expensive. NIRPS will use a high order adaptive optics system to couple the starlight into a fiber corresponding to 0.4” on the sky as efficiently or better than HARPS or ESPRESSO couple the light 0.9” fiber. This allows the spectrograph to be very compact, more thermally stable and less costly. Using a custom tan(θ)=4 dispersion grating in combination with a start-of-the-art Hawaii4RG detector makes NIRPS very efficient with complete coverage of the YJH bands at 110’000 resolution. NIRPS works in a regime that is in-between the usual multi-mode (MM) where 1000’s of modes propagates in the fiber and the single mode well suited for perfect optical systems. This regime called few-modes regime is prone to modal noise- Results from a significant R and D effort made to characterize and circumvent the modal noise show that this contribution to the performance budget shall not preclude the RV performance to be achieved.

The direct detection of photons emitted or reflected by extrasolar planets, spatially resolved from their parent star, is a major frontier in the study of other solar systems. Direct detection will provide statistical information on planets in 5–50 AU orbits, inaccessible to current Doppler searches, and allow spectral characterization of radius, temperature, surface gravity, and perhaps composition. Achieving this will require new, dedicated, high-contrast instruments. One such system under construction is the Gemini Planet Imager (GPI). This combines a high-order/high-speed adaptive optics system to control wavefront errors from the Earth's atmosphere, an advanced coronagraph to block diffraction, ultrasmooth optics, a precision infrared interferometer to measure and correct systematic errors, and a integral field spectrograph/polarimeter to image and characterize target planetary systems. We predict that GPI will be able to detect planets with brightness less than 10 −7 of their parent star, sufficient to observe warm self-luminous planets around a large population of targets. To cite this article: B. Macintosh et al., C. R. Physique 8 (2007).

A new, inexpensive polarimetric unit has been constructed for the Dominion Astrophysical Observatory (DAO) 1.8-m Plaskett telescope. It is implemented as a plug-in module for the telescope's existing Cassegrain spectrograph, and enables medium resolution (R~10,000) circular spectropolarimetry of point sources. A dual-beam design together with fast switching of the wave plate at rates up to 100Hz, and synchronized with charge shuffling on the CCD, is used to significantly reduce instrumental effects and achieve high-precision spectropolarimetric measurements for a very low cost. The instrument is optimized to work in the wavelength range 4700 - 5300A to simultaneously detect polarization signals in the H beta line as well as nearby metallic lines. In this paper we describe the technical details of the instrument, our observing strategy and data reduction techniques, and present tests of its scientific performance., 32 pages, 15 figures. Accepted for publication in PASP

Exoplanet imaging is driving a race to higher contrast imaging, both from earth and from space. Next-generation instruments such as the Gemini Planet Imager (GPI) and SPHERE are designed to achieve contrast ratios of 10 -6 - 10 -7 this requires very good wavefront correction and coronagraphic control of diffraction. GPI is a facility instrument, now in integration and test, with first light on the 8-m Gemini South telescope expected by the middle of 2012. It combines a 1700 subaperture AO system using a MEMS deformable mirror, an apodized-pupil Lyot coronagraph, a high-accuracy IR interferometric wavefront calibration system, and a nearinfrared integral field spectrograph to allow detection and characterization of self-luminous extrasolar planets at planet/star contrast ratios of 10 -7. In this paper we will discuss the status of the integration and test now taking place at the University of Santa Cruz California. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE)., Astronomical Adaptive Optics Systems and Applications IV, August 21-24, 2011, San Diego, CA, USA, Series: Proceedings of SPIE

For less than $2000 in materials we have exploited the DAO 1.8 m Cassegrain spectrograph between 430 and 800 nm for differential linear spectropolarimetry at resolutions up to ∼30,000 by using a beamsplitting cube as single-channel analyser. The position angle of the cube is under microprocessor control and, to counteract the highly erratic response of the spectrograph image-slicer combination to linear polarisation, we convert to circular polarisation by inserting a quarter-wave plate. The analyser has ∼40% throughput (c.f. 50% ideal) and we can sense polarisation levels as small as 0.01% with a CCD. Incomplete action of the quater-wave plate is probably the ultimate limit to precision. Details of the reduction procedure are given together with illustrative results for the Be star ϕ Per.

SPIE Astronomical Telescopes + Instrumentation, 2006, Orlando, Florida , United States, Series: Proceedings of SPIE; no. 6272

SPIE Astronomical Telescopes + Instrumentation, 2006, Orlando, Florida, United States, Series: Proceedings of SPIE; no. 6272

Optics and Photonics 2005, 2005, San Diego, California, United States, Series: Proceedings of SPIE; no. 5903

SPIE Astronomical Telescopes + Instrumentation, May 24-31, 2004, Glasgow, United Kingdom, Series: Proceedings of SPIE; no. 5492

Second Backaskog Workshop on Extremely Large Telescopes, September 9-11, 2003, Backaskog, Sweden, Series: Proceedings of SPIE; no. 5382

Altair is the facility Adaptive Optics (AO) system for the Gemini North Telescope on Mauna Kea, Hawaii. Designed to take advantage of the excellent natural seeing conditions that Gemini North will experience, Altair is also unique in that the Deformable Mirror (DM) is conjugate to a fixed altitude of 6.5 kilometers. Running at a control loop speed of at least one kHz, the reconstructor for this high order AO system is subject to a number of conditions that drove its design and implementation. Initial studies indicated that a single RISC CPU would be capable of performing the reconstruction for Altair, as opposed to the more common solution of multiple DSP processors. We present some of these conditions, the results of a throughput benchmark test that verified the choice of hardware, some components of the processing steps of the reconstructor and a summary of the current status of the project.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.