The evolution of black hole states

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

5

2

n

a

J

4

2

v

7

95

2

1

4

/

h

p

-

o

rt

sa

:v

i

X

r

aTheevolutionofblackholestatesJeroenHomanMITCenterforSpaceResearch70VassarStreet,Cambridge,MA02139,USAjeroen@space.mit.eduTomasoBelloniINAF/OsservatorioastronomicodiBreraViaE.Bianchi46,23807,Merate(LC),Italybelloni@merate.mi.astro.itAbstract.WediscusstheevolutionofblackholetransientsonthebasisofafewsystemsthatwereintensivelyobservedwiththeRossiX-rayTimingExplorer.Wefocusontheglobalevolutionandtheobservedstatetransitions.Ratherthangivinganumericalrecipeforclassifyingobservations,wetrytoidentifytimesduringoutburstsatwhichclearchangesoccurintheX-rayvariability,X-rayspectral,ormulti-wavelengthproperties.1.IntroductionSincethelaunchoftheRossiX-rayTimingExplorer(RXTE)about～20blackholeX-raytransientshavebeenobservedwithenoughcov-eragetostudytheirglobalevolution.Theseobservationshaveprovidedawealthofinformationandhavealreadyledtoaconsiderableincreaseinourunderstandingofthesesystems.InarecentreviewbyMcClin-tockandRemillard(2004)anewclassi cationschemewasproposedforthespectralandvariabilitystatesasobservedinblackholetran-sients.McClintockandRemillard(2004)approachedthestatesissuebyidentifyingthree‘stable’statesinblackholetransients.Inthispaperweapproachtheissuefromanotherangle,focusingontheobservedtransitions,theoverallevolutionduringanoutburst,andhowX-raychangesrelatetochangesatotherwavelengths.

2.Statede nitions

Untilthelate1990sitwasgenerallyassumedthatthestateofablack-hole

M˙systemwasdeterminedbytheinstantaneousmassaccretionrate,.Itwasbelievedthatasthemassaccretionrateincreased,asourcewentthroughthefollowingstates(seee.g.Esinetal.,1997):quiescence→low/hard→intermediate→high/soft→veryhigh.ObservationswithRXTEofsourceslikeXTEJ1550–564haveshownthatsuch c2008KluwerAcademicPublishers.PrintedintheNetherlands.

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

2

˙-drivenpicture,withtransitionsonlybeingtriggeredbyasimpleM˙,isprobablynotabletoexplaintheobservedtransitionchangesinMbetweenthestates.Homanetal.(2001)suggestedthatanadditionalparametermayplayaroleinthosetransitions.Theyalsosuggestedthatthevery-highstateandtheintermediatestate(s)areoneandthesamestateandrepresenttransitionsbetweenthelow/hardandhigh/softstatesatdi erentluminosities.Thefactthatmostofthestateswereobservedoverwideandoverlappingrangesinluminosityalsomeantthatattributeslike‘low’,‘high’and‘veryhigh’hadlostmostoftheirsigni cance.

McClintockandRemillard(2004)introducedanewclassi cationschemethatispartlybasedontheold ve-statesscheme,butnolongerusesluminosityasaselectioncriterionsinceitappearedthatanyoftheactivestatesmayoccuratanyluminosity.Theystillrecognizeaquiescentstate,hardstate,softstate(renamingthelatterthe‘thermaldominantstate’),andvery-highstate(renamingitthesteeppower-lawstate),butdroptheintermediatestateasabona destate.Thethreeactivestatesarede nedonthebasisofthefractionalcontributionofthedisk- ux(orpower-law ux)tothe2–20keVspectrum,spectralpower-lawindex,andthestrengthofthepowercontinuum.Allobser-vationsthatcannotbeclassi edaccordingtotheirstatede nitions,arecombinedintoanintermediatestate,inwhichobservationscanshowpropertiesofanyofthethreemainstates.

Someofthestatetransitionsdiscussedinthispaperinvolve(andarede nedonthebasisof)suddenchangesinthepropertiesofthequasi-periodicoscillations(QPOs)inthe～1–10Hzrange.Currentlythreetypesoftheselow-frequencyQPOsarerecognizedinblackholebinaries,calledtypeA,BandC(Wijnandsetal.,1999,Remillardetal.,2002).Thethreetypescanbedistinguishedonthebasisofstrength,coherence,phaselags,energydependence,harmoniccontent,andfrequencystabilityonatimescaleofdays.TypeCQPOsarethemostcommonones;theyareobservedinthespectrallyhardstatesoverawiderangeinfrequency(～0.1–10Hz),andarestrongerandmorecoherentthantheothertwotypes.TypeAandBQPOshaveonlybeenobservedinafewsources;theyareonlyseeninthevery-high/steeppower-lawstate,inanarrowfrequencyrange(～4–8Hz).RecentobservationsofH1743–322(Homanetal.,2004b)suggestthatthesetwotypesmightbemoreintimatelyrelatedthanwaspreviouslybelieved.TransitionsfromonetypeofQPOtoanotheralwaysseemtoinvolvetypeB(Casellaetal.,2004),withtransitionsbetweentypeCandBresultinginaclearchangeintheshapeandstrengthofnoisecontinuum.ThemainreasonforincludingQPOtypeinourdiscussionofblackholestatesisthattheyprovideanadditionalindicationfor

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

3

changesintheaccretion owthatmaynotalwaysshowupasstrongspectraltransitions.

3.Globalevolution

Hardness-intensitydiagrams(HIDs),inwhichtheX-raycountrateisplottedversusanX-raycolor,provideaquickwaytostudytheglobalevolutionofblackholetransientsduringoutburst.InFigure1weplotthelightcurvesandHIDsoffourtransientsthatwereobservedwithRXTEbetween1999and2003.ItshouldbenotedthatconstantcountratelevelsintheseHIDscorrespondtosubstantiallyhigherluminositiesathardnessvaluescloseto1thanatvaluesof0.001-0.01.TheHIDsaresimilartoeachotherinthatallfoursourcesseemtotraceout(partof)acounter-clockwiseq-shapedtrack.Belowacertaincountratethespectrumisalwaysveryhard(i.e.inthehardstate)andabovethespectrumiseitherveryhardorverysoft,exceptfortwotransitionalphases(the’horizontal’branchesintheHID).Thismeans,aswasnotedbyotherauthorsaswell(seee.g.MaccaroneandCoppi,2003),thatwithinasingleoutburstthehard→softtransitionoccursata uxthatisaboutafactorof10–100higherthanthesoft→hardtransition.NotethatinGX339–4andXTEJ1650–500thehard→softtransitionwasratherfast,whileinXTEJ1859+226andH1743–322thesourcelingeredforalongertimeatintermediatecolors.

WhilethesourcesshowninFigure1showasmoothoverallmove-mentthroughtheirHID,thefasttimevariabilityandmulti-wavelengthpropertiesallowonetode neafewrathersharpboundariescorrespond-ingtostatetransitions.Inthefollowing,wewillbaseourdiscussionofstatesmostlyonthe2002/2003outburstofGX339-4,theresultsofwhichwillpresentedinBellonietal.(2004)andHomanetal.(inprep.).Completereferencesforourdiscussioncanbefoundinthoseworks.

4.Adetailedlookatthestates

4.1.Thehardstate-riseanddecay

Sincepointedobservationsofatransientinoutburstoftenstartonlywhenthesourcealreadyhasaluminositythatisafactorofmorethan104–105abovethequiescentlevel,notmuchisknownabouttheearlyevolutionofoutbursts.ThankstoamonitoringcampaignsetupbyDavidSmithandco-workers,the2002/2003outburstofofGX339–4

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

4

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

5

Figure2.AnRXTElightcurveoftheriseofthe2002/2003outburstofGX339–4.Thetimesofthe rstsigni cantPCAandASMdetectionsareindicated,asarethepre-outburstandquiescencelevels.Thetwograylinesshowthepresenceoftwodi erenttimescalesduringtheearlyrise.

2003).InFigure2weshowtheearlyevolutionofGX339-4.Fromthis gureitisclearthatbeforethe rstASMdetectionthesourceluminosityhadbeenincreasingforatleast40days,initiallyslowlyandlatermorerapidly.

Throughouttheseearlystagesoftheoutburst,untilithadreacheditspeak3–100keV ux,thesourcewasinthehardstate:thestrengthofthebroad-bandvariabilitydecreasedfrom45%rmsto30%rmsandtheenergyspectrumwasdominatedbyapowerlawcomponent,withtheindexslowlyincreasingfrom1.3to1.4.DuringtherisethefrequenciesofthenoisecomponentsandtheoccasionalQPOincreasedgradually.Anexampleofapower-densityspectrumfromthisstateinGX339-4isshowninFigure3.

Justafterreachingitspeak ux,increasesinthepower-lawindexandnoise/QPOfrequenciesaccelerated.Also,astrongincreaseofthespectrallysoftdiskcomponentandasubstantialdecreaseintheop-tical/IR ux(seeFig.4)wereobservedatthattime,withthelatterprobablybeingtheresultofthejetswitchingo (orstartingto,Homanetal.,2004a).Atthispointthesourceenteredanintermediatestate(see§4.2),withthetransitionfromthehardstatebeingvisibleasanalmost90 turntotheleftintheHID.Notethatinthede nitionofMcClintockandRemillard(2004)sourcesstayinthehardstateuntilthepower-lawsteepensbeyondanindexof2.1.Inourviewthehardstateislimitedtoonlythehardestpower-lawdominatedspectrawithindicesaround1.3–1.5,asmanychangesoccur(simultaneously)whenthepower-lawbecomessteeper.

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

6

Figure3.Examplesofpower-densityspectraofGX339-4fromthefourstatesdiscussedinthetext.

Attheendofthe2002/2003outburstGX339-4returnedtothehardstate,similartowhatisobservedinmost,ifnotall,blackholetransients.IntheHIDthiscanbenicelyseenasthelowerhorizontalbranchbendingdowntostartrunningparallelto,andinfactnearlyontopof,thehardstatebranchthatwastracedoutduringtherise.Such‘saturation’ofthespectralhardnesswasalsoobservedinXTEJ1650–500(Rossietal.,2003,seealsoFig.1).ItisinterestingtonotethatonceGX339-4reachedthehardnessatwhichitoriginallyleftthehardstatebranch,theoptical/IRshowedastrongincrease(seelightcurvesinBailynandFerrara,2004),indicatingthatthejetdoesnotbecomevisibleintheoptical/IR(orswitchon)untilthehardstatebranchisreached(aswasalreadysuggestedbyKalemcietal.,2004basedonobservations4U1543–47).Thespectralhardeningtowardsthehardstateisnotnecessarilyamonotonicprocess,ascanbeseenintheHIDofGX339-4andXTEJ1859+226.

ObservationsofhardstatebranchesextendingovermanyordersofmagnitudeinGX339-4andXTE1650–500indicatethatthehardstateaccretion owgeometry(whichlikelygivesrisetostrongout ows)canexistoverawiderangeinmassaccretionrate.

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

7

4.2.Thehardstate softstatetransitions

Immediatelyafterleavingandbeforereturningtothehardstate,blackholetransientsareobservedinanintermediatestate,withspectralpower-lawindicesbetweenroughly1.5–2.5.Wearenotawareofanyexceptiontothis.Thisstateisdi erentfromthehardstateinsev-eralaspects.Dependingonwhethertheintermediatestateisobservedduringthehard→softorsoft→hardtransition,sourcesshowaclearsteepening/ atteningofthespectralpowerlawcomponent,astrongincrease/decreaseinthenoiseandQPOfrequencies,andanincreas-ing/decreasingfractionaldisk ux,comparedtothehardstate.Allthesepropertiesevolvesmoothlyfromandtothehardstate.Infact,withouttheHIDandoptical/IRinformation(seeFig.4)itwouldbedi culttoexactlypin-pointthetransitionbetweenthesetwostates.Inthecaseofthehard→softtransitionthemovementtotheleftintheHIDisduetothecombinationofincreaseddisk uxandsteepeningofthepowerlaw.Inthetimingdomain,thebroad-bandvariabilitycomponentsseeninthepowerdensityspectrumincreasetheirchar-acteristicfrequencies,showinganevolutionthatclearlylinksthemtothecorrespondingcomponentsinthehardstate.AcleartypeCQPOappears,alsowithacharacteristicfrequencyincreasingwithtimeanddecreasinghardness(seeBellonietal.(2004)).Atypicalpower-densityspectrumfromtheintermediatestateisshowninFigure3.

Itisimportanttonotethatthehard→intermediatestatetransitiondoesnotalwaysoccuratthesame uxlevel,ascanbeseenfromFigure

4.Duringthe2004outburstofGX339–4thistransitionoccurredata uxlevelthatwasaboutafactorof4lowerthanin2002.Thetransitionin2004wasprecededbyasmallhardstateoutburst,whichsuggeststhatthe uxlevelatwhichthetransitionoccursdependsontherecentaccretionhistory.AfterpassingthroughtheintermediateGX339-4continuedtobrighteninthesoftsateduringits2004outburst.

Anotherimportantpointtonoteisthefactthattheoccurrenceoftheintermediatestatedoesnotseemtodependonthetimederivative˙.InXTEJ1650–500itoccurredduringthedecay,butinGX339–ofM˙wasapparentlystillincreasing,aswitnessedbythesecond4whileM(soft)maximuminthelightcurve.However,inbothcasesthetransitionresultedina(temporary)dropinthecountratebyafactorof～2.Takingoncemorethe2002/2003outburstofGX339–4asatem-plate,weseethatwhenthehardnessgoesbelowawellde nedthresh-old,thetimingpropertieschangesharply:acleartypeBQPOappearsinthepowerdensityspectrum(Figure3,seealsoCasellaetal.,2004forsimilarbehaviorinXTEJ1859+226).InmostsourcesthechangefromtypeCtotypeBQPOsseemstotakeplacewhenthepower-law

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

8

Figure4.Leftpanel:X-ray/IRcorrelationforthe rstpartofthe2002/2003out-burstofGX339-4(Homanetal.,2004).Thedi erentbehaviorforthedi erentstatesisevident.Rightpanel:HIDofthetwomostrecentoutburstsofGX339-4:2002/2003(gray)and2004(black).

indexhasavaluearound2.5-3.0.Infact,power-lawswithsuchindicesareaccompaniedbyagreatvarietyoftimingproperties:notonlytypeA,BorCQPOs,butalsoveryweakvariabilitylikethatseeninthesoftstate.

Wewillrefertothepartofthetransitionduringwhichthepower-lawindexchangesbetween～1.5–2.5andwhichshowstypeCQPOsandstrongband-limitednoiseasthehardintermediatestate.Thepartofthetransitionwherethepower-lawindexisrelativelyconstantaroundavalueof2.5–3.0andduringwhichthesourceoccasionallyshowstypeAandBQPOsontopofweakerrednoisewillbereferredtoasthesoftintermediatestate.NotethatinGX339-4thesoftintermediatestatealsoshowedobservationswithweakbandlimitednoiseand/orQPOsthatwewerenotabletoclassify.Itisthereforemoreacollectionofdi erenttypesofbehavior,betweenwhichthesourcecouldswitchonatimescaleofaday,ratherthanawellde nedstate.

Itisimportanttonotethatthechangefromthehardintermediatetothesoftintermediatestatewasrepeatedagaininthe2004outburstatthesamespectralhardness.Duringthe2002/2003outburstahugeradio are/ejectioneventwasobservedaroundthetimeofthechangefromthehardintermediatetothesoftintermediatestate(Galloetal.,2004,Fenderetal.,2004).Althoughitistemptingtoassociatesucha arewiththistransition,itshouldbementionedthatsimilarradioeventsarealsoobservedinGRS1915+105(Bellonietal.,2000),asourceforwhichcharacteristictypeAandBQPOswerenotobservedtodate.However,giventhefasttimescalesoftransitionsinthissystem,

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

9

itispossiblethatsuchQPOsappearforintervalsshorterthanforothersources,whichwouldmakethemdi culttoobserve.

Itisduringthesoftintermediatestatethatmosthigh-frequencyQPOshavebeendetected,indicatingthattheremightbearelationbetweenthoseandtypeA/BQPOs;indeed,thefrequenciesofbothfeaturesarenotobservedtovarybyalargeamountbetweendi erentobservations.ItispossiblehoweverthatthehighfrequencyQPOsinsoftintermediatestateevolvefrombroaderfeaturesinthehardin-termediatestate,asissuggestedbyobservationsofXTEJ1650–500(Homanetal.,2003).Noticethatwhilethesoftintermediatestateisoftenobservedathigh uxbetweenthehardintermediateandthesoftstates,thesametimingpropertiesarenotobservedatlow ux,whenthereversetransitiontakesplace.Moreover,inXTEJ1550–564(Homanetal.,2001)typeAandBQPOsappearedatseveralwellseparatedluminositylevels,stronglysuggestingtheyarenotstrictlyrelatedtohard softtransitions.InGX339-4astrong1HzQPOwithsomepropertiessimilartothoseofthetypeBQPOsisobservedatlow ux,indicatingthatitispossiblethatasimilarstateexistalsoatmuchloweraccretionrate,althoughwithdi erentcharacteristicfrequencies(Bellonietal.,2004).

4.3.Thesoftstate

Duringthesoftstate,whichinGX339-4tookplaceafterthesoftintermediatestate,thespectralandtimingpropertiesareratherwellde ned,althoughasinglecleartransitionfromthesoftintermediatestateishardtoidentify.Theenergyspectrumofthesoftstateisdom-inatedbyastrongthermalcomponent,withthepresenceofaweaksteeppower-lawcomponent,whichwasnotobservedtoshowahigh-energycuto (seeGroveetal.,1998).Variabilityinthesoftstateisweakcomparedtotheotherstates,withtypicalrmsamplitudesofatmostafew%rms.Unfortunately,bythetimemosttransientsreachthesoftstatetheyareusuallyinthedecayphaseandobservationshavebecomeshorterandlessfrequent,sodetailedstudiesofitsvariabilitypropertiesarerare.Nevertheless,afewweakQPOshavebeendetectedinthesoftstatesofGROJ1655–40,XTEJ1550–564,andH1743–322.TheseQPOsallhadfrequenciesthatwerehigherthantheotherlowfrequencyQPOsdetectedinthosesourcesandthenoisecontinuacouldallbe ttedwithbrokenpowerlaw.Surprisingly,theQPOandbreakfrequenciesofthesepowerspectrafallontopoftheWijnands-vanderKlisrelation(Wijnands&vanderKlis1999)forblackholesinthehardandhardintermediatestates.ThissuggestsnotonlythatthesemightbetypeCQPOs,butmoreimportantly,thatvariability

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

10

Figure5.TheHIDofthe2002/2003outburstofGX339-4.Cleartransitionsaremarkedbygraysegments.Thebranchescorrespondingtothefourbasicstatesintheq-trackarelabeled(Bellonietal.,2004).

propertiesthatoncewerethoughttobecharacteristicofthehardandhardintermediatestatesarestillpresentinthesoftstate,althoughinamuchweakerform.

4.4.Discussion

Althoughthepicturepresentedhereissomewhatsimpli ed,asaddi-tionalcomplicationshavebeenobserved,wecansketchthestatesbyusingoncemoreGX339-4asatemplate(seeFig.5andFenderetal.,2004).Asshownabove,thehardintermediateandsoftintermediatestatesarekeptseparate,asbothspectralandtimingevolutionshowmarkeddi erences.

Thehardstateandthehardintermediatestateshavemuchincom-mon.Spectrally,theyaredominatedbyahardcomponentforwhichahigh-energycuto isobserved(Groveetal.,1998).Inthetimingdomain,thecomponentsobservedinthepowerdensityspectruminthesetwostatesareclearlyrelated,ascanbeseenfromtheevolutionoftheircharacteristicfrequencies(Bellonietal.,2004).Nevertheless,somethinghappenstotheaccretion owasthesourcemovesfromthelow/hardstatetotheintermediatestate,ascanbeseenfrommulti-wavelengthstudies(Homanetal.,2004a).Thisislikelytoberelatedto

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

11

changesinthejet,whichcouldberesponsibleforpartoftheobservedX-ray ux(Fenderetal.,2004)asisalsoindicatedbythefactthatradioemissionisalwaysobservedinthesestates.

Thesoftstateandsoftintermediatestatearespectrallysomewhatrelated.Theenergyspectrumisdominatedbythethermaldiskcompo-nent,withasteephardcomponentwithnoevidenceofahigh-energycuto .Thepowerdensityspectrumlacksband-limitedcomponentsandshowsonlyQPOssuperimposedonapower-lawcomponent.Noradioemissionisobserved(i.e.onlyupperlimitsontheemissionfromthecompactsource),indicatingthattheproductionofajetisterminatedatthetransitiontosoftintermediatestate(Fenderetal.,2004)andmaybeevenbefore.Duringthesestates,theaccretion owisclearlydi erentfromtheothertwo.Intermsofvariabilityhowever,thesoftstatesharessomepropertieswiththehardstateandhardintermediatestate,withthetypicalvariabilitytimescalesfollowingthesamerelationasseeninthosestates.Ifthehardstatevariabilitypropertiesarelinkedtojetproduction,thepresenceofrelated(butmuchweaker)variabilityinthesoftstatecouldindicateaveryweak(i.e.belowcurrentdetectionlimits)jetinthatstateaswell.

Inadditiontothesegeneralproperties,thereisanumberofimpor-tanttopicswhosedetaileddiscussionisbeyondthescopeofthepresentpaper.Mostnotably,thefasttransitionsobservedbetweendi erentstates(neverinvolvingthehardstate,whichisonlyreservedforthebeginningandtheendofanoutburst)needtobestudiedindetail,astheyprobablyholdthekeyforadeeperunderstandingofthephysicsofthestatesandtheirassociationtothejet.Also,somesourcescanhavebrightoutburstswithouteverleavingthehardstate,indicatingthatonceagaintheinstantaneousmassaccretionrateisnotwhatdeterminesthetransitions.However,therecenthistoryofthemassaccretionratemayplayanimportantrole(thiscanalsobeseeninFig.4,asGX339-4wasobservedtoleavethehardstateareverydi erent uxlevels).Asecondaryaccretion ow(Smithetal.,2002;Yuetal.,2004)orchangesintheComptoncooling/heatingintheaccretiondiskcorona(Meyer-Hofmeisteretal.,2004)seemtobepromisingtoexplainsomeoftheseissues.Forexample,delaysbetweenafast(i.e.intermsofpropagationspeed)secondary owandaslowerdisk owcouldaccountfortheobservedhysteresis.

Inconclusion,thehysteresisbehaviorthatcanbeseenfromtheHIDsinFigure1,putforwardforthe rsttimebyMiyamotoetal.(1995),wasfoundwithRXTEtobeacharacteristicpatternforblack-holetran-sients.Despitemanycomplexities,generalfeatureshavebeenshowntorelatetotheejectionofpowerfulrelativisticjets,whichcanleadtoadeeperunderstandingofthephysicalpropertiesoftheaccretion ow.

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

12

Thepicturepresentedhere,scaledtolongertimescales,shouldalsobevalidforAGNs.Inthesesources,thereisnocontributionoftheopticallythickaccretiondiskintheX-rayband,butthepathshowninFig.5isqualitativelysimilarifthediskcontributionisremoved.Recently,Cui(2004)presentedaverysimilardiagramfortheRXTEobservationsofthehighlyvariableAGNMkn421,showingthatindeedtheschemeofaccretionstatescouldapplytosystemsoveralargescalesofmasses.

JHwishestothankJonMillerandRonRemillardfornumerousdis-cussionsonthetopicofblack-holestates.

References

Bailyn,C.andL.Ferrara:2004,‘GX339-4:ContinuedOpticalandInfra-redDecline’.TheAstronomer’sTelegram323.

Belloni,T.,J.Homan,P.Casella,M.vanderKlis,E.Nespoli,W.Lewin,J.Miller,andM.M´endez:2004,‘Theevolutionifthetimingpropertiesoftheblack-holetransientGX339-4durirngits2002/2003outburst’.AstronomyandAstrophysicsp.submitted.

Belloni,T.,M.Klein-Wolt,M.M´endez,M.vanderKlis,andJ.vanParadijs:2000,‘Amodel-independentanalysisofthevariabilityofGRS1915+105’.AstronomyandAstrophysics355,271–290.

Casella,P.,T.Belloni,J.Homan,andL.Stella:2004,‘Astudyofthelow-frequencyquasi-periodicoscillationsintheX-raylightcurvesoftheblackholecandidateXTEJ1859+226’.AstronomyandAstrophysics426,587–600.

Corbel,S.,M.A.Nowak,R.P.Fender,A.K.Tzioumis,andS.Marko :2003,‘Radio/X-raycorrelationinthelow/hardstateofGX339-4’.AstronomyandAstrophysics400,1007–1012.

Cui,W.:2004,‘X-rayFlaringActivityofMrk421’.astro-ph/0401222.

Esin,A.A.,J.E.McClintock,andR.Narayan:1997,‘Advection-dominatedAccre-tionandtheSpectralStatesofBlackHoleX-RayBinaries:ApplicationtoNovaMUSCAE1991’.TheAstrophysicalJournal489,865.

Fender,R.P.,T.M.Belloni,andE.Gallo:2004,‘Towardsauni edmodelforblackholeX-raybinaryjets’.MonthlyNoticesoftheRoyalAstronomicalSociety355,1105–1118.

Gallo,E.,S.Corbel,R.P.Fender,T.J.Maccarone,andA.K.Tzioumis:2004,‘Atransientlarge-scalerelativisticradiojetfromGX339-4’.MNRAS347,L52–L56.Grove,J.E.,W.N.Johnson,R.A.Kroeger,K.McNaron-Brown,J.G.Skibo,andB.F.Phlips:1998,‘Gamma-RaySpectralStatesofGalacticBlackHoleCandidates’.TheAstrophysicalJournal500,899.

Homan,J.,M.Buxton,S.Marko ,C.Bailyn,E.Nespoli,andT.Belloni:2004a,‘Multi-wavelengthobservationsofthe2002OutburstofGX339–4:twopat-ternsofX-ray–optical/near-infraredbehavior’.TheAstrophysicalJournalp.submitted.

Homan,J.,M.Klein-Wolt,S.Rossi,J.M.Miller,R.Wijnands,T.Belloni,M.vanderKlis,andW.H.G.Lewin:2003,‘High-FrequencyQuasi-periodicOscillations

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

13

intheBlackHoleX-RayTransientXTEJ1650-500’.TheAstrophysicalJournal586,1262–1267.

Homan,J.,J.M.Miller,R.Wijnands,M.vanderKlis,T.Belloni,D.Steeghs,and

W.H.G.Lewin:2004b,‘High-andlow-frequencyquasi-periodicoscillationsintheX-raylightcurvesoftheblackholetransientH1743-322’.TheAstrophysicalJournal,inpress,astro-ph/0406334.

Homan,J.,R.Wijnands,M.vanderKlis,T.Belloni,J.vanParadijs,M.Klein-

Wolt,R.Fender,andM.M´endez:2001,‘CorrelatedX-RaySpectralandTimingBehavioroftheBlackHoleCandidateXTEJ1550-564:ANewInterpretationofBlackHoleStates’.TheAstrophysicalJournals132,377–402.

Kalemci,E.,J.A.Tomsick,M.M.Buxton,R.E.Rothschild,K.Pottschmidt,S.

Corbel,C.Brocksopp,andP.Kaaret:2004,‘Multi-wavelengthobservationsoftheGalacticblackholetransient4U1543-47duringoutburstdecay:statetransitionsandjetcontribution’.astro-ph/0409092.

Maccarone,T.J.andP.S.Coppi:2003,‘HysteresisinthelightcurvesofsoftX-ray

transients’.MNRAS338,189–196.

McClintock,J.E.andR.A.Remillard:2004,‘BlackHoleBinaries’.astro-

ph/0306213.

Meyer-Hofmeister,E.,B.F.Liu,andF.Meyer:2004,‘Hysteresisinspectralstate

transitions-achallengefortheoreticalmodeling’.astro-ph/0411145.

Miyamoto,S.,S.Kitamoto,K.Hayashida,andW.Egoshi:1995,‘Largehystereticbe-

haviorofstellarblackholecandidateX-raybinaries’.TheAstrophysicalJournall442,L13–L16.

Remillard,R.A.,G.J.Sobczak,M.P.Muno,andJ.E.McClintock:2002,‘Char-

acterizingtheQuasi-periodicOscillationBehavioroftheX-RayNovaXTEJ1550-564’.TheAstrophysicalJournal564,962–973.

Rossi,R.,J.Homan,J.Miller,andT.Belloni:2003,‘Statetransitionsinthe

2001/2002outburstofXTEJ1650-500’.astro-ph/0309129.

Smith,D.M.,W.A.Heindl,andJ.H.Swank:2002,‘TwoDi erentLong-Term

BehaviorsinBlackHoleCandidates:EvidenceforTwoAccretionFlows?’.TheAstrophysicalJournal569,362–380.

Wijnands,R.,J.Homan,andM.vanderKlis:1999,‘TheComplexPhase-Lag

Behaviorofthe3-12HZQuasi-PeriodicOscillationsduringtheVeryHighStateofXTEJ1550-564’.TheAstrophysicalJournall526,33.

Yu,W.,M.vanderKlis,andR.Fender:2004,‘TheCorrelationbetweenHardX-Ray

PeakFluxandSoftX-RayPeakFluxintheOutburstRiseofLow-MassX-RayBinaries’.TheAstrophysicalJournalLetters611,L121–L124.

We discuss the evolution of black hole transients on the basis of a few systems that were intensively observed with the Rossi X-ray Timing Explorer. We focus on the global evolution and the observed state transitions. Rather than giving a numerical recipe

homan_belloni.tex; 2/02/2008; 15:28; p.14

本文来源：https://www.bwwdw.com/article/xgh1.html