Flight Performance of the AKARI Cryogenic System
[摘要] WedescribetheflightperformanceofthecryogenicsystemoftheinfraredastronomicalsatelliteAKARI,whichwassuccessfullylaunchedon2006February21(UT).AKARIcarriesa68.5cmtelescopetogetherwithtwofocal-planeinstruments,InfraredCamerasandFarInfraredSurveyor,allofwhicharecooleddowntocryogenictemperaturetoachievesuperiorsensitivity.AKARIhasauniquecryogenicsystem,whichconsistsofcryogen(liquidhelium)andmechanicalcoolers(2-stageStirlingcoolers).Withthehelpofmechanicalcoolers,179L(26.0kg)ofsuper-fluidliquidheliumcankeeptheinstrumentscryogenicallycooledformorethan500days.Theon-orbitperformanceoftheAKARIcryogenicsisconsistentwiththedesignandapre-flighttest,andtheboil-offgasflowrateisassmallas0.32mgs$$^{-1}$$.WeobservedanincreaseinthemajoraxisoftheAKARIorbit,whichcanbeexplainedbythrustduetothethermalpressureofventedheliumgas.
[发布日期] [发布机构]
[效力级别] [学科分类] 天文学(综合)
[关键词] "infrared: general";"instrumentation: miscellaneous";"space vehicles: instruments" [时效性]
