The Cryogenic System for the VIRUS Array of Spectrographs on theHobby-Eberly Telescope

摘要

The Hobby-Eberly Telescope (HET) is an existing innovative large telescope of 9.2 meter aperture, located at theMcDonald Observatory in West Texas. The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) requires amajor upgrade to the HET, including a substantial increase in the telescope field of view, as well as the development andintegration of a revolutionary new integral field spectrograph called VIRUS. The Visible Integral-Field Replicable UnitSpectrograph (VIRUS) is an instrument comprising approximately 150 individual IFU-fed spectrographs which will bemounted on the telescope structure. Each spectrograph has a CDD camera detector package which must be cryogenicallycooled during scientific operation. In order to cool each of these camera systems a liquid nitrogen system has beenproposed and design study completed. The proposed system includes: a liquid nitrogen source, vacuum jacketdistribution system, local storage on the telescope, and distribution under a thermal siphon to the individualspectrographs and local thermal connectors.