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AGN/QuasarswithHST
• Ac9vegalaxiesandquasars:studiesoftheac9vephenomenathemselves,andoftheproper9esofthehostgalaxiesthatharborthem.
• AGN:Agalaxynucleusthatshowsevidenceforaccre9onontoasupermassiveblackhole
Taxonomy• UV/opt/IRluminosity:– Quasars(Lnuc>Lgal)– StrongAGN(Lnuc<Lgal)– WeakAGN(Lnuc<<Lgas)
• RadioLuminosity(jetpower)– RadioQuiet(LR<1e‐4Lopt)– RadioLoud(LR>0.1Lopt)
• ViewingAngle– Broad+NarrowLines(canseeBLR)(type1)– Narrowlinesonly(can’tseeBLR)(type2)
Quasars&QSOs
• Mostarefoundbetweenz=2‐4– Nowmorethan60atz>5.7.Mostdistantz~7
• TypicalQSOL>100‐105xLMW
• TriggeredbygasflowingonSMBHatahighrate– Currentlyrateofgasconsump9onmustbemuchless
QSOspectrum• QSOcon9nuum–rela9velyflat• BroademissionfeaturesproducedbytheQSO(nearSMBHandaccre9ondisk)(highlyredshifed)
• CanbeIntrinsicabsorp9onlines(CIV)• Interveningabsorp9onlines
• Mbh‐σRela9on
Co‐evolu9onofSMBHsandGalaxies
β=4.377+/‐0.29α=‐0.51+0.049σ0=200km/s[localquiescentgalaxies]Kormendy&Ho2013 (GOODREVIEW!!)
Ferrarese&Merris2000,Gebhardt2000,Tremaine2002
Magorrian98rel’n
BlackHoleMassDetermina9on:1)Reverbera9onMapping
• Temporaloffsetsbetweencon9nuumandemission‐linevariabilityallowonetodeterminethedistancefromtheBHtothebroademissionlineregion(BLR)R
Blandford&McKee1982
Peterson1993
Reverbera9oncont’d
• Assumingtheemissionlinesarebroadenedprimarilybythevirialgasmo9onsinthegraivta9onalpoten9al:
• Linewidth,VfromBLRbroademissionline+assump9onofvirializa9onatBLR
MBH=frV2/G
2)Single‐epochvirialBHmasses9mators
• Reverbera9onmappingrevealscorrela9onbetweenBLRsize,R,andluminosityofcon9nuum(Kaspi2000,2005)
RαLϒ,ϒ=0.5
• VirialTheorem:M=fv2R/G
• FWHMofthebroadHβ(MgII)• Meanscanfindmassesusingsingleepochspectra
BLRSize
Kaspi2005
a=0.91,b=0.5,c=2Vestergaard&Peterson2006Feng+2014Shen+2015
BulgeVelocitydispersion• EmissionlinesurrogatesfromtheNLR:[OIII]line
• AssumesNLRgasorbitsinthegravita9onalpoten9alofthehostgalaxybulge
• Green&Ho2005–showedthatσOIIItendstooverpredictσ*(contamina9onfromAGN)
• Lowerioniza9onlinesOII,SIIalsowork(butlargescaser)
• Newresults:Shen+2015
Evolu9onwithZ?Whenaretherela9onsestablished?
Salviander2013SDSSDR7
Lineisthelocalrela9onfromTremaine2002
ColoredpointsareaverageMBHandσperredshifbin
BlueHO3:0.1<z<0.8HβforMBH,OIIIforσopencircles
RedMO2:0.4<z<1.35MgIIforMBH,OIIforσclosedcircles
Seemstosuggestposi9veevolu9on(BHgrowthprecedesthatofbulge)Hugedebateaboutthis.
SDSSReverbera9onMappingproject• 0.1<z<1.09
• Spectroscopicallymonitor88QSOswiththeSDSSIIIBOSSspectrograph
• Newσ*measurements–decomposedspectraintohostandQSO
• Rela9on*does*existathighz
• Slopeismuchshallowerthanlocalrela9on‐bias
• Nostrongevolu9onwithredshif,buttherela9onmaygetflaserathigherz
Shen+2015
TightRela9onsMean:
• BHaffectsgalaxystructureatscalesthataremuchlargerthanitsownsphereofinfluencefromgravityalone~100pcvsRbulge=2Kpc
• SMBHsandGalaxycoevolu9onisestablishedatz~1
ExploringGalaxyAssembly&SMBHGrowthwithHST
• A)WhatarethehostsofQSOs?
• B)WhattriggersQSOs?
• C)SMBHs&Galaxycoevolu9on?Whatregulatesthecorrela9ons(M‐sigma)?
B)WhatTriggersQSOs?
• Causemustbemorecommonathighz
• Needtoexplainco‐evolu9onofSMBHandgalaxy
• TwoLeadingtheories–Mergers(majororminor)
– Gravita9onalinstabili9esingalaxydisks
4Hopkinsetal.
FIG . 1 .— An sc hema ti c out li ne of the phas es of growth in a “typica l” galax y undergoin g a gas -rich majo r m erger. Im age Cre di t: (a ) NOAO/AURA/NS F; (b) REU program /NOAO/AURA/NSF; (c )NAS A/ST ScI/ACS Science Team; (d) Opti ca l (le ft): NA SA/STScI/R . P. van der Marel & J. Gerssen; X-ray (right): NASA/CXC/MP E /S. Kom oss a et al .; (e) Left : J. Bahc al l/M. Disne y/NASA; Right: Gem-ini Observatory/NS F/University of Hawaii Institu te for As tronom y; (f) J. Bahcall/M . Dis ney/NASA; (g) F. Schweizer (CIW /DTM); (h ) NOAO/AURA/NSF.
MergerHypothesis: Hopkins+2006,2008
Gravita9onalInstabili9es• Highzgasdiskshavehighgas
densi9es,con9nuouslyfedbystreams(50%gasfrac9ons)
• GasdisksareunstableQ~1,forminggiantstarformingclumpsandtransientperturba9ons
• Gravita9onaltorquesfromtheseperturba9onsleadtoinflows
• Inflowrates~10M/yr(1+z)3/2
• Endswhencosmologicalaccre9onratedeclinesandthesystembecomestellardominated
Bournaud(2011),Dekel(2009)
Differen9a9ngbetweenthetwoscenarioswithHST:
highspa9alresolu9onimaging
• Predictdifferenthostgalaxymorphologies– Distorteddiskswith9dalstructuresVSStar‐formingdiskgalaxiescomposedofclumpydisksandgrowingspheroids
– QuiescentmergerremnantvsStarformingDisk(Red/GreensequencevsBlueCloud)
• Predictdifferentdistribu9onsofcoolgasandSFintheenvironmentofSMBH
LackofEvidenceforMergers?
QSOsfoundinCANDELSaboutnormallookinggalaxies
(exceptfortoplef)
26outof30showednoobvioussignsofmergers
ProposalA
Strengths:Theproposershaveiden9fiedveryinteres9ngobjectswithspa9allyresolvedhostgalaxiesaspartoftheirsurveyofverybrightLBGs.Becauseoftheirspa9allyresolvednature,studyofthehostmorphologyseemsnatural.
Weaknesses:Ontheotherhand,withonlythreetargets,12orbitsseemslikeafairlylargeinvestment.Furthermore,theproposallaysoutextremelylofygoals(e.g.,findevidenceofcoldflows)thatseemdifficulttoachievewithonlymeasurementsofhostgalaxymorphology.Itisnotclearwhythesetargetsarepar9cularlysuitedtobethesmokinggunofcoldflows,norhowexactlytheproposedobserva9onswouldprovidecompellingevidenceoftheseflows.
C)SMBH&GalaxyCo‐Evolnathighredshif
HostgalaxiesofQSOsatz~6shouldhaveULIRGproper9es(verifiedbyCO,Submmobserva9ons)
WhataretheirSFRs?
Lietal.2007:
severalmajormergers,formstheSMBHatz~6.5inthemostmassivehaloina3Gpc3boxEnvironment?
~40knownQSOsatz>6Mbh>1e9M
Universe<1Gyrold
Massincontext• MostmassiveQSOSMBHatz>6.3
• Isn’tsuperhighz,but*muchmoremassive*
Wu+2015
(Originallythrownoutsincebrightenoughtobein2MASS!)
MaysuggestthatBHsgrowfasterthanhostsathighz
ProposalBStrengths:Thisisafascina9ngobjectthatdeservestobestudiedinmoredetail.Theproposedsciencegoalscanprovidevaluableinsightintotheproper9esofthehostgalaxyintheveryearlyuniverse,reioniza9on,andearlystructureforma9on.ThepanelappreciatedthediscussionofthepreviouslysuccessfulmethodofPSFsubtrac9on.
Weaknesses:Thecoordinatedparallelswerenotstronglyjus9fied.Itwasunclearhowrepresenta9vethisextraordinaryobjectisandhowtointerprettheobserva9ons.Thistargetisfromtheop9callyselectedSDSSsamplewhichisincomplete;adiscussionofwhethersimilarlymassivecandidatesmaybeinIRsurveyssuchasWISEwouldhavebeenhelpful.TherewasalsosomeconcernthatthePSFsubtrac9onwouldnotbeassuccessfuldueto,e.g.Poissonnoise,becausethetargetisbrighterthantheexampleintheproposal.TheachievabilityofthisfromthegroundwithAOwasnotruledout.