DESIGN AND DIMENSIONING OF HERSCHEL INSTRUMENT COOLING HELIUM SYSTEM

摘要

Herschel is the fourth cornerstone mission in theEuropean Space Agency (ESA) science programme. Itwill perform imaging photometry and spectroscopy inthe far infrared range.As for any Infrared observatory, the achievement ofobservation relies on the instrument cooling. OnHerschel, it is ensured by a 2400 litre reserve ofsuperfluid Helium at 1.8K (Helium Two state). Onceoperational Herschel will offer a minimum of 3 years ofroutine observations.AIR LIQUIDE was chosen by EADS Astrium to designand manufacture major components of the Herschelspacecraft cryostat : storage tanks, tubing, thermalshields and thermal links. All these elements contributeto the final aim of the system to provide cold sources toHerschel observation instruments. The main designdriver for this Helium system is to ensure propercryostat insulation and sufficient thermal link with theinstruments.This paper presents the design challenges met by AIRLIQUIDE, the dimensioning solutions implemented bythe structural team and the final design of the Heliumsystem.