Trip to Héðinn

Members of the CMBeam team went on a site visit to Hedinn hf to track progress on the construction of our new cryostat. This cylindrical structure, approximately 1.5 m in diameter and 1.0 m in length, consists of three thermal stages: a 300-K vacuum vessel, a 40-K radiation shield, and a 4-K cold stage. The two cryogenic stages are cooled by a Bluefors PT420 pulse-tube cryocooler and are mechanically supported by six thermally isolating G10 flexures positioned near the mid-plane of the system. The cryostat provides sufficient volume to perform holographic measurements of the full three-lens refractor optical systems designed for the Taurus experiment as well as other refracting telescopes and optical tubes for the cosmic microwave background. This system represents the first cryostat ever built in Iceland.