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1.
1 IntroductionThe〔CII〕1 5 8μm ( 2 P3 /2 →2 P1/2 )emissionlineoftendominatesthegascoolingintheneu tralphaseofthegalacticISM (interstellarmedium) .ThislineiswellcorrelatedonagalacticscalewithFIR (far-infrared)continuum ,whichtracesthecoolingofdustgrains.Nearlyconstantin…  相似文献   

2.
1 IntroductionThemagneticfieldandmaterialmotionhavealwaysbeenthepointstowhichcloseatteneionispaidinthestudyofsolarflareprocess.Especiallythetwistingenergystorgeprocessisaprob lemthatauthorsofmanyflaretheoriesandmodelshopetoresolve .Gold&Holye ( 1 96 0 ) pres…  相似文献   

3.
1 IntroductionSingleStellarPopulations (SSPs)arethebasicbuildingblocksofsyntheticspectraofgalaxies(Bressanetal1 994) .Intheframeworkoftheevolutionarypopulationsynthesisstudy ,SSPsaremodelledwithproperstellarevolutionarytracksofdifferentmassesandinitialchemi…  相似文献   

4.
1 IntroductionTheobjects ,0 748 1 2 6and 2 2 5 1 1 5 8( 3C45 4 3) ,arequasars.Theyallhaveanopticallybrightnucleus.Thecompactnuclei,emittingstrongradioradiationatcentermeterwavelength ,aretypicalAGNs .TheradioemissionregionintheAGNsisverysmallinsizeWehavecarriedoutsnapshot…  相似文献   

5.
1 IntroductionThemetallicitydeterminationisoneofthemostessentialworksinastronomy .ToinvestigatetheformationhistoryofourGalaxy ,theinformationaboutpositions,spatialmotions,andagesofcomponentstarsareindispensable .TheHipparcosmissiongaveuseahugedatabaseabo…  相似文献   

6.
1 Purposesoffollow upspectroscopyThepurposesofourfollow upspectroscopyofsupernovaeareasfollows ;● Identificationofthetypeandphase (datesbefore/aftermaximum)ofnewlydiscoveredsupernovaatanearlystage .Identificationoftypeandphaseshouldbedoneasearlyaspossible.…  相似文献   

7.
1 IntroductionUltraluminousfar infrared (UFIR) galaxiesareoneoftheimportantdiscoveriesmadebyI RAS .Theluminositiesofthesegalaxies,>1 0 12 L⊙ ,are 2to 3ordersofmagnitudehigherthanthoseofmostofspiralgalaxies,totheluminositydomainofquasars .Thesourceofenergyforsuchg…  相似文献   

8.
1 IntroductionLightwaves ,departedfromdistantstars,keepaperfectwavefrontuntiltheyarereachingtheearthatmosphere.Atmosphericturbulenceinducesspatialandtemporalvariationsintheairrefractiveindexandresultsinrandom phasedelaysinthepropagatingwavefront.Atmosph…  相似文献   

9.
1 IntroductionsThediscoveryofmeterwave (~ 1 0 - 30 0MHz)spikebursts (fastdriftingburstswithveryshortdurationsatfixedfrequencies)canbetracedbacktothe 1 96 0’sbyDeGrootandtheirchar acteristicsofnarrow band (therelativewavebandislessthanafewpercent)andveryshortemis si…  相似文献   

10.
1 IntroductionInthemorethan 5 0yearsfromthatthesolarradioastronomywasborn ,peoplehavecarriedoutagreatdealofobservationsandstudiesonradioemissionphenomena ,butitwasdonefewinradioabsorptionphenomena .Infactinthesolaratmosphericplasma ,theradiationandabsorpti…  相似文献   

11.
1 IntroductionTTauristarsandtheirsurroundingcircumstellardisksgrowbyaccretionofmattercausedbydynamicalinfalloftheprotostellarenvelopes .Recently ,severalobservationsofprotostellaren velopeswithmillimeterarraysweremade ,providingstrongevidenceforinfallint…  相似文献   

12.
1 IntroductionArarelargeTypeⅣmicrowaveburstwasobservedatYunnanobservatorywithPhoenixⅡMicrowaveSpectrometeratthreefrequencies ( 1 42 ,2 84and 4 0 0GHz)from 0 8h31 mto 0 9h41 mUTonDecember 1 6 ,1 988.ThisrarelargeTypeⅣμburstappearedovertheactiveregionNOAA/USAF 5 2 78,comingfroma…  相似文献   

13.
1 TheKuiperBeltObjectsThesolarsystemisbelievedtocondenseoutofaninterstellarcloudofgasanddust,inwhichthehot ,centralpartcontractedtoformwhatlaterbecametheSun ,whereasinasurroundingro tatingdisk -likestructure ,solidgrainparticlescontinuedtogrow ,andeventual…  相似文献   

14.
1 IntroductionThesolaractivecycleisusuallydescribedwiththerelativesunspotnumbers.Analysesofhis toricaldataontherelativesunspotnumbershaverevealedawealthofinformationaboutthesolaractivecycle (HongQinfang 1 990 ,1 994;ZhongShuhua 1 991 ,1 995 ) .Theso called 1 1 yearpe rio…  相似文献   

15.
1 IntroductionWeplantodevelopthedualchannelreceiver,whichisusedtomakethesimultaneousobser vationat 1 0 0GHzand 1 5 0GHzbands.TheSISmixersareusedfortwobands.Toconstructthedualchannelreceiversystem ,thequasiopticalsystemhastobeconsideredfirstofall.Thebeamfromthe…  相似文献   

16.
1 IntroductionAsaresultofmanyyears’efforts,Chineseastronomicalcommunityhaslaiddownasolidas tronomicalobservationalfoundation ,whichisfiguredbythe 2 .1 6mand 1 .5 6mopticaltelescopes,the 1 .2minfraredtelescope ,thesolarmagneticfieldandmulti channeltelescope ,the 1 3.7m…  相似文献   

17.
1 IntroductionCKBoowasdiscoveredandconfirmedtobeacontactbinarybyBond ( 1 975 ) .Afteritsdis coverythesystemisobservedfrequently (e .g .Aslan ,1 978;AslanandDerman ,1 986 :PajdoszandZola ,1 987;Krzesinskietal.,1 991andJiaetal.,1 992 ) .Asreportedbyseveralauthors,thelightcurveofthesy…  相似文献   

18.
Shu Chenggang        Yin Xiao     《天文研究与技术》1999,(Z1)
1 IntroductionTheLyman breaktechnique (e .g .Steidel,Pettini&Hamilton 1 995 )hasnowbeenprovedverysuccessfulinfindinglargenumbersofstarforminggalaxiesatredshiftz~ 3(e .g .Steideletal.1 996 ,1 999b) .TheobservednumberdensityandclusteringpropertiesofLyman breakgalax ies (her…  相似文献   

19.
1 IntroductionThemolecularradiationofC18O(J =1 - 0 )intheCepheusChasbeenobserved (Yuetal.1 996 ) .Themulti corestructurewasobtained ,i.e.therearethreecoresofC18O(J =1 - 0 )inCepheusC ,whicharerepresentbya,b ,andc (Yuetal.1 996 ) .Inordertostudythemulti corestructureofC18O(J =1 - 0 )int…  相似文献   

20.
1 IntroductionTheearthquakeinearthproducesaglobalstaticdisplacementfieldbythedislocation .Thisdisplacementfieldinturnchangestheearth’sinertiatensor,henceexcitingthevariationofbothpolarmotionandlengthofday .Recently ,Chaoetal( 1 995 )havecomputedchangesofspin…  相似文献   

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