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Studying AGN & QSOs with HST

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StudyingAGN&QSOswithHST

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)

Viewingperspec9ve

WadsmorthPublishing

NLR10pc–1kpc

BLR~0.02–0.1pc

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

Othercorrela9onsshouldexist…?

Stanley+2015

BlackHoleMassDetermina9on:1)Reverbera9onMapping

• Temporaloffsetsbetweencon9nuumandemission‐linevariabilityallowonetodeterminethedistancefromtheBHtothebroademissionlineregion(BLR)R

Blandford&McKee1982

Peterson1993

CourtesyM.Bentz

r=characteris9csizeoftheBLR

Bentz+2006

NGC4151

TheobservableUV/op9calcon9nuumandionizingcon9nuumvaryinphase.(~6days=r/c)

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)?

A)QSOHosts?HSTshowedthatQSOhostsaregalaxies

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

QSOwithshells

LackofEvidenceforMergers?

QSOsfoundinCANDELSaboutnormallookinggalaxies

(exceptfortoplef)

26outof30showednoobvioussignsofmergers

AbstractProposalA

Facts

Problem

Goal

HSTFixesProblem

BroaderImpact

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

Newchallenge…Mbh=(1.24+/‐0.19)x1010M (!!!1e9washard!!!)

Wu+2015

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.