A New 60-cm Radio Survey Telescope with the Sideband-Separating SIS Receiver for the 200 GHz Band

[摘要] Wehaveupgradedthe60-cmradiosurveytelescopelocatedinNobeyama,Japan.Wedevelopedanewwaveguide-typesideband-separatingSISmixerforthetelescope,whichenablesthesimultaneousdetectionofdistinctmolecularemissionlinesinboththeupperandlowersidebands.OvertheRFfrequencyrangeof205–240GHz,thesingle-sidebandreceivernoisetemperaturesofthenewmixerare40–100Kforthe4.0–8.0GHzIFfrequencyband.Theimagerejectionratiosaregreaterthan10dBoverthesamerange.FordualIFsignalsobtainedbythereceiver,wehavedevelopedtwosetsofacousto-opticalspectrometersandatelescopecontrolsystem.Usingthenewtelescopesystem,wesuccessfullydetectedthe$$^{12}$$CO($$J=$$2$$-$$1)and$$^{13}$$CO($$J=$$2$$-$$1)emissionlinessimultaneouslytowardOrionKLin2005March.Usingthewaveguide-typesideband-separatingSISmixerforthe200GHzband,weinitiatedthefirstsimultaneous$$^{12}$$CO($$J=$$2$$-$$1)and$$^{13}$$CO($$J=$$2$$-$$1)surveyofthegalacticplaneaswellaslarge-scalemappingobservationsofnearbymolecularclouds.

[学科分类] 天文学(综合)

[关键词] "instrumentation: detectors";"radio lines: ISM";telescopes