MSE: Instrumentation for a massively multiplexed spectroscopic survey facility

Abstract

MSE is a massively multiplexed spectroscopic survey facility that will replace the Canada-France-Hawaii-Telescope. This 11.25-m telescope, with its 1.5 square degrees field-of-view, will observe 4,332 astronomical targets in every pointing by using fibers to pick up the light at the prime focus w and transmitting it to banks of low/moderate (R=3,000/6,000) and high (R=30,000) resolution spectrographs. Piezo actuators position individual fibers in the field of view to enable simultaneous full field coverage for both resolution modes. A Calibration system ensures good quality and reliable raw data. This instrument suite, dedicated to large scale surveys, will enable MSE to collect a massive amount of data: equivalent to a full SDSS Legacy Survey every 7 weeks. Since 2018, MSE has made progress by refining the science cases, exploring design space for the instrumentation and understanding the limits of chosen telescope and instrument architecture to achieve the science cases. To improve performance and reduce risk, challenging conceptual designs for spectrographs have been reconsidered. As well, the science calibration plan and associated technical hardware system have been developed to a conceptual design level. This paper includes a discussion of the trades, design decisions and outstanding risks for the entire instrument suite with a focus on recent developments for the spectrographs and calibration system.