SPIRou is a near-infrared (nIR) spectropolarimeter / velocimeter for the Canada-France-Hawaii Telescope (CFHT), that will focus on two forefront science topics, (i) the quest for habitable Earth-like planets around nearby M stars, and (ii) the study of low-mass star/planet formation in the presence of magnetic fields. SPIRou will also efficiently tackle many key programmes beyond these two main goals, from weather patterns on brown dwarfs to Solar-System planet and exoplanet atmospheres. SPIRou will cover a wide spectral domain in a single exposure (0.98-2.44 µm) at a resolving power of 70 K, yielding unpolarized and polarized spectra of low-mass stars with a 15% average throughput at a radial velocity (RV) precision of 1 m s −1 . It consists of a Cassegrain unit mounted at the Cassegrain focus of CFHT and featuring an achromatic polarimeter, coupled to a cryogenic spectrograph cooled down at 80 K through a fluoride fiber link. SPIRou is currently integrated at IRAP/OMP and will be mounted at CFHT in 2017 Q4 for a first light scheduled in late 2017. Science operation is predicted to begin in 2018 S2, allowing many fruitful synergies with major ground and space instruments such as the JWST, TESS, ALMA and later-on PLATO and the ELT.

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Resistive wall modes have been investigated in a reversed field pinch (Reversatron IIi [IEEE Trans. Plasma Sci. PS-16, 667 (1988)]) operated with three different boundary conditions: (1) a copper shell having a magnetic penetration time τs comparable to the discharge duration, (2) a brass shell having τs comparable to the setting-up time, and (3) no shell, which gives τs much shorter than the setting-up time. The brass shell is found to impede the growth of the m=1, n=−6 ‘‘on-axis’’ mode observed to grow in the setting-up phase of no-shell discharges. In the sustainment phase, there is a higher level of m=1 modes than with the copper shell and the discharge duration, ion temperature, and plasma current are reduced. The mode spectrum is broad in the sustainment phase and the degradation in discharges cannot be attributed to any single mode. There is evidence for transient mode locking resulting in a slinky mode in copper-shell discharges.

The Canada France Hawaii Telescope Corporation (CFHT) plans to repurpose its observatory on the summit of Maunakea and operate a new wide field spectroscopic survey telescope, the Maunakea Spectroscopic Explorer (MSE). MSE will upgrade the observatory with a larger 11.25m aperture telescope and equip it with dedicated instrumentation to capitalize on the site, which has some of the best seeing in the northern hemisphere, and offer its user's community the ability to do transformative science. The knowledge and experience of the current CFHT staff will contribute greatly to the engineering of this new facility.MSE will reuse the same building and telescope pier as CFHT. However, it will be necessary to upgrade the support pier to accommodate a bigger telescope and replace the current dome since a wider slit opening of 12.5 meters in diameter is needed. Once the project is completed the new facility will be almost indistinguishable on the outside from the current CFHT observatory. MSE will build upon CFHT's pioneering work in remote operations, with no staff at the observatory during the night, and use modern technologies to reduce daytime maintenance work. This paper describes the design approach for redeveloping the CFHT facility for MSE including the infrastructure and equipment considerations required to support and facilitate nighttime observations. The building will be designed so existing equipment and infrastructure can be reused wherever possible while meeting new requirement demands. Past experience and lessons learned will be used to create a modern, optimized, and logical layout of the facility. The purpose of this paper is to provide information to readers involved in the MSE project or organizations involved with the redevelopment of an existing observatory facility for a new mission.

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