Youareetonominatespeakerstocolloquium@.Thevideoandslidesofpreviouscolloquiaandmoreinformationcanbefoundat 2021年第7次/No.72021 Time:Wednesday2:30PM,Jun.2ndLocation:A601,NAOC Ellipticalretiondiskasamodelfortidaldisruptionevents Dr.FukunLiu(KIAA-PKU) Dr.FukunLiuisaprofessorofastrophysicsandtheformerdirectoroftheDepartmentofAstronomyofPekingUniversityandjointprofessorofKIAA-PKU.HeisamemberofthesupervisorsoftheChineseAstronomicalSociety.HeobtainedhisPhDinastrophysicsatSISSA(Italy)in1999andworkedwithProfessorMarekAbramowiczatChalmersUniversityofTechnologyandGothenburgUniversityasapost-doctoralfellowoftheNaturalScienceResearchFoundationofSweden(NFRfellow)from1999to2001.HejoinedPekingUniversityin2001.HisresearchinterestsincludeAGNs,retiondisktheory,supermassiveblackholeandbinaries(SMBHBs),gravitationalwaveastrophysics,andtidaldisruptionevents.Togetherwithcolleagues,hepredictedtheobservationalsignaturesanddiscoveredthefirstpairsofSMBHBsinquiescentgalaxies.HisresearchgrouprecentlydevelopedtheellipticalretiondiskmodelforTDEs.HewasawardedtheTop10AchievementsinAstronomyofChina,respectively,in2011and2014andreceivedthespecialallowancesoftheStateCouncilofChinain2016. Abstract Astarwouldbetidallydisrupted,whenitcloselypassesbyasupermassiveblackhole(SMBH).Afterthetidaldisruption,abouthalfofthestellardebrisesboundandfallsbacktotheSMBH.Inthecanonicalmodel,thestellardebriscircularizesrapidlytoformacircularretiondiskofsizeabouttwicetheorbitalpericentreofthestar.Thecircularretiondiskishotwithtemperatureaboutafewtimes10^5KandradiatesmainlyinthesoftX-rays.Stellartidaldisruptionevents(TDEs)discoveredintheX-raysareconsistentwiththeseexpectations,butthoseintheoptical/UVbandarenot.Theobservationsoftheluminousopticalluminosities,sub-Eddingtonbolometricluminosities,lowandconstantblackbodytemperature,largeanddecreasingemittingregions,andstrongplexasymmetricbroadopticalemissionsoftheoptical/UVTDEschallengethecanonicalmodel.WerecentlyproposedanddevelopedanellipticalretiondiskmodelforTDEs.Weinvestigatedthepropertiesoftheellipticalretiondiskandshowedthattheellipticalretiondiskshavedistinctivehydrodynamicstructuresandspectralenergydistributions,whicharefullyconsistentwiththeobservationsofoptical/UVTDEs.Inthistalk,IwillintroducetheellipticalretiondiskmodelforTDEsparethepredicationswiththeobservationsofTDEs. 暨国家天文台组建20周年学术报告Colloquiumforthe20thanniversaryofNAOC