The SDSS-V Local Volume Mapper instrument (LVM-I): Enclosure design, construction, and performance

The Sloan Digital Sky Survey V (SDSS-V) Local Volume Mapper (LVM) is an ultra-wide field high spatial resolution IFU survey of the Milky Way, the Magellanic Clouds, and a sample of galaxies in the local volume. Observations are carried out with the LVM Instrument (LVM-I), a specially designed robotic telescope, instrument, and facility located at Las Campanas Observatory (LCO) in Chile. The LVM-I is hosted in a custom-built roll-off type enclosure that protects the hardware, allows for simultaneous observations towards different directions in the sky by the four LVM-I telescopes, provides a thermally controlled stable and clean environment for the LVM-I spectrographs, supplies all necessary utilities (e.g. power, communications, LN2 detector cooling) to the different LVM-I sub-systems, provides environmental telemetry and information, and integrates with the LVM-I control software to operate in an automated fashion. In this paper we discuss the design of the LVM-I enclosure, its construction, and an evaluation of its performance. The LVM-I was successfully integrated on-site and commissioned during the first half of 2023, with the enclosure design and performance meeting its requirements and allowing for the start of the SDSS-V LVM project science operations.