Observing Black Holes (BHs) The First Discoveries - Discovery (1961-63) Quasi-Stellar Radio Sources as the most energec and distant members of a class of objects. - Center of a giant Ellipcal Galaxy è Blazar: AGN with Relavisc jet 3C273 - Cosmological red-shi z = 0.158 cz ≈ dH(t0) from the Hubble-law we get the distance of 2.5 Gyr (750 Mpc) - Discovery (1972) binary BH system “In the case of Cyg X-1 black hole – is the most conservave hypothesis” Edwin Salpeter Cyg X-1 Orbits, 5.6 days, an unseen opcally (but bright X-ray) object. The companion has a mass of ~ 30 M¤ \]$%.'#$_*8$7$%B'($*75$*B-##*;1%*<=)*>?@*"=*b$D,$%c#*,-Z* V-##*;L(.C1(*;2V3*;1%*"'(-%=*#=#7$B#** 2V]_*>?%-=*.1BD-.7*#7-%R*V.1BD_*!DC.-,*.1BD-('1(*#7-%R*i*W*V.eV]3* !"$%&-C1(-,*D-%-B$7$%#_*d1%"*Y*SQJ*O-=#R**-*#'(&$&Y*X*N! O*Y*GQS*/D.** G @eG 2-_**#$B'?B-P1%*-]'#R*'_*1%"'7-,*'(.,'(-C1(*-(),$R*b*W*&%*#'($*2@?$ 3 _*,'($*1;* #')57*#D$$O3* ;2V3*W*UQGffge?UQUUJ*V!R*-##LB'()*V.1BD*W*GUV!R*-(O*9B1#7*,'/$,=E*'**Y* GHQ@ge?UQXh** * ***********V]*Y*@fQX*V!* <-&$-7_** 2#'(*$3*75$*'(.,'(-C1(*-(),$*"$7Z$$(*2Uh*?*IUh3*.-(*'(7%1OL.$*,-%)$*L(.$%7-'(7=*-(O*'#*B1#7,=*(17* Z$,,*O$7$%B'($OQ* \.,'D#$*\iL-C1(* G* @eG* M'(*'*m*2*2@?Nne-3 3 M'(*'*m*o@?UQGF@fp2ie2@gi33GeFq@eG* +0*fj@JFU?fH** VFF*>?Hl*+0*@SQJS*VR*d1%"*W*FQfS* \>!*UHfX?JHJ**\>!*UHfX?JHJ* '*W*HfQJ*k*@QU* BHs as astronomical sources • Primordial BHs They have been formed at the early stages of the universe Not discovered, yet. Only upper limits (mostly from gamma-ray observaons). • Stellar mass BHs (mainly this lecture) 7 8 A typical galaxy like the Milky Way should harbour 10 − 10 stellar black holes There are more than twenty good candidates in close binary systems. Accreon, jets. Observed at all wavelenghts. Isolated stellar mass BHs are not discovered up to now. But there are interesng candidates among microlensing events. • Intermediate mass BHs Their existence is uncertain, but there are good candidates among ULX. Observed in radio, x-rays, and opcs. • Supermassive BHs (Sgr A* this lecture) There are many good candidates with mass esmates. In the center of our Galaxy with extremely high certainty there is supermassive BH. Accreon, jets, dal discrupons of normal stars. Observed at all wavelenghts. • Micro BHs Forms at Planck scales. There are no observaonal evidences. CERN: Micro BH created by -27 HE 14 TeV p-p collisions by the LHC, they would disintegrate rapidly, in around 10 7 seconds. Hawking radiaon “BHs evaporate by radiang away their energy” Formaon of Stellar Black Holes Note: The fact that General Relavity does predict the existence of BHs and that General Relavity is a reliable theory of gravitaon does not necessarily prove the existence of BHs, because General Relavity does not describe the astrophysical processes by which a BH may form. E.g., White Holes, Wormholes, Parallel Universe, Travelling in me exist from GR, but they exist in real ? <1%$?.1,,-D#$*#LD$%(1&-*D%1)$('71%#* a$Z*B1O$,#*D%$O'.7*75-7*B1#7*1;*#7-%#* w@XV * D%1OL.$* +0#* 2#$$* 75$* %$&'$Z* `*#7-%*BL#7*5-&$*-7*,$-#7*X*CB$#R* ! MB-%x*-%>'&_*@SUfQUGJFS3* "L7*(1*B1%$*75-(*fU*71*SU*CB$#R* 75$* B-##* 1;* 75$* ML(* 2<3* 71* L(O$%)1* <1%$?.1,,-D#$* #LD$%(1&-* $]D,1#'1(Q* r!***0')5*B-##*2;$Z3* r!***n1Z?B-##*2B-P1%'7=3* r!***jn>*A*L,7%-,LB'(1L#*>?%-=*#1L%.$#* •! V1#7*1;*,1Z?B-##*-%$*7%-(#'$(7#Q* •! V'.%1iL-#-%#l*M-B$*B-'(* D%1D$%C$#*,'/$*KL-#-%#* y$7#* +0*5-&$*a!*0`:N* yQ*`Q*s5$$,$%* Some records M33 X-7 15.65+/-1.45 Msolar (Orosz et al. 2007). Paredes arXiv: 0907.3602 BH candidates Among 20 good galacc candidates 17 are X-ray novae. 3 belong to HMXBs (Cyg X-1, LMC X-3, GRS 1915+105). New candidates sll appear. For on of the latest see 1008.0597 (J. Orosz, from astro-ph/0606352) Candidates properes (astro-ph/0606352) Also there are about 20 “candidates to candidates”. Detector MAXI recently added several new BH candidates BH Spectrum !"#$%&'()$#(*+!"#$%&'()$#(*+ ,-*..$#&'()$#%&+%+-*/+&()&01(21&3)*&34&-1*&23/53)*)-+&,-*..$#&'()$#%&+%+-*/+&()&01(21&3)*&34&-1*&23/53)*)-+& (+&$&23/5$2-&3'6*2-&$22#*7)8&/$9*#(+&$&23/5$2-&3'6*2-&$22#*7)8&/$9*# :);*#&+3/*&23);(73)+&$)&:);*#&+3/*&23);(73)+&$)& $22#*73)&;(+<&2$)&43#/ $22#*73)&;(+<&2$)&43#/ =(+23+(-% =(+23+(-% !!!!!!!!"#$%&!'()**)+,!- !!!!!!!!"#$%&!'()**)+,!- >1*&!"#$%&,5*2-#?/&(+&=*#%&23/5.*@A& >1*&!"#$%&,5*2-#?/&(+&=*#%&23/5.*@A& • &>1*#/$.&*/(++(3)&4#3/&-1*&$22#*73)&;(+<&B/?.7"'.$2<'3;%C& •• &>1*#/$.&*/(++(3)&4#3/&-1*&$22#*73)&;(+<&B/?.7"'.$2<'3;%C&&D*5#32*++()8&'%&*)*#8*72&*.*2-#3)+&B0$#/&8$+E&F*-+EC& &G?21&/3#*HHH&B*/(++(3)&I&$'+3#573)&4*$-?#*+J&#*K*273)J&*-2HHHC •• &D*5#32*++()8&'%&*)*#8*72&*.*2-#3)+&B0$#/&8$+E&F*-+EC& • &G?21&/3#*HHH&B*/(++(3)&I&$'+3#573)&4*$-?#*+J&#*K*273)J&*-2HHHC X-ray binaries Black Hole X-ray spectra historically observed/classified in X-rays !"#$%&'()$#(*+ './ !+,- (%)&%'()* !"#$%&'' './ !+,- JETs X-ray binaries Corona T~107 K M-1/4 – last stable orbit temperature at Eddington luminosity Opcs/UV – QSO X-ray - μQSO X-ray Binary Jets exist on all scales X-ray binaries Low-Luminosity AGN Mirabel & Rodriguez (1994) VLBI: Falcke, Nagar, Wilson et al. (2000) Jets Oen the radio emission is more symmetric on the large scale and asymmetric on the small scale The core is defined based on the spectral index: flat (α ~ 0)‏ [to find which component is the radio core is not always easy: core free-free absorpon can complicate the story!] A prototypical radio galaxy Lobes Core Hot-spots Jets § Any size: from pc to Mpc § First order similar radio morphology (but differences depending on radio power, opcal luminosity & orientaon)‏ § Typical radio power 1023 to 1028 W/Hz Jet Formaon • All relavisc cosmic jet sources may be connected by a common basic mechanism – A promising model for that is magnetohydrodynamic acceleraon by rotang, twisted magnec fields • “Spin Paradigm” can explain qualitavely a number of stascal properes of AGN – Geometrically thick accreon flows are more efficient at launching jets • In Microquasars this principle may explain the correlaon between the producon of a jet and the presence of a hot, geometrically thick accreon flow • This also may be testable in some Seyfert AGN as well – Slow acceleraon and collimaon of these jets is probably the norm • There is some evidence for this in AGN jets – Highly relavisc jet flows may be produced by strong, straight magnec fields • All galacc cosmic jet sources, including supernovae and gamma-ray bursts, may be connected by a common origin as well: different outcomes of the last stage of evoluon in a massive star Basic Principles of Magnetohydrodynamic Jet Producon • Basic MHD mechanism: – Blandford (1976); Lovelace (1976) – Acceleraon by rotang black holes (Blandford & Znajek [1977]) – Acceleraon by rotang [thin] accreon disks (Blandford & Payne [1982]) • First numerical simulaons: Uchida & Shibata (1985) • Key ingredients in their “Sweeping Pinch” mechanism – Thick accreon disk or torus – Keplerian differenal rotaon (Ω ∝ R-3/2) – Inial strong vercal magnec field (strong enough to slow disk rotaon) – J × B force splits up into magnec pressure and tension: -∇ (B2 / 8π) + (B • ∇B) / 4π • Typical results (e.g., Kudoh et al [1998]; Uchida et al. [1999]) – Differenal rotaon twists up field into toroidal component, slowing rotaon – Disk accretes inward, further enhancing differenal rotaon and Bϕ – Greatest field enhancement is at torus inner edge 2 – Magnec pressure gradient (dBϕ / dZ) accelerates plasma out of system 2 – Magnec tension [hoop stress] (–Bϕ /R) pinches and collimates the oulow into a jet – Oulow jet speed is of order the escape velocity from the inner edge of the torus (Vjet ~ VAlfven ~ Vesc) – Jet direcon is along the rotaon axis Kudoh, Matsumoto, & Shibata (2002) Simulated jet evolution in the ISM !"#$%&'()$#(*+ radio IR opt X-ray Disc BH hard state Jet high energy companion tail! star (inner regions) !"#$%&'()$#(*+ radio IR opt X-ray Disc BH soft state Jet ? high energy companion tail! star (inner regions) ComplexComplex Physics vs.Physics simple vs. exercises simple exercises a word on radiative efficiency Complex Physics vs. simple exercises a word on radiative efficiency XBs LR ! LX 0.6 radiatively AGN inefficient Spin of a Black Hole 45$*;L,,*1"#$%&$O*.1(C(LLB*#D$.7%LB* 6$*$B'##'1(*,'($* <1BD71('^-^'1(* :%1(*$O)$* 45$%B-,*O'#/* N$}$.C1(*.1BD1($(7* •! N$}$.C1(*"LBD* •! 6,L1%$#.$(7*bÖ*,'($#* •! :%1(*,'($*O1B'(-7$#* •! JQf*/$u*e*JQH*/$u* •! a-%%1Z*,'($g"LBD* •! N$,-7$O*71*5-%O*}L]*-(O** .1&$%'()*;-.71%*ÜeGá* N$#7?;%-B$*>?%-=*<1BD71('^$O** %$}$.C1(*#D$.7%LB*;1%*'1('^-C1(** N$=(1,O#*Å*a1Z-/*2GUUG3* d-%-B$7$%#*à* N$,-C&'#C.*)%-&'7-C1(-,*",L%%'()*$Ä$.7* à*W*U* à*W*fR*N'(*WGN)*** d1Z$%?,-Z* *#D$.7%LB*â*W*G** n1)*à*W*F* à*W*U*R*N'(*W@UN)** !"#$%&$O*bÖ*6$*,'($* •! +%1-O*2Z'O75*1;*-*;$Z*/$u3* -(O*#1B$CB$#*%$O#5'{$O*6$* b?#5$,,*,'($*D%1|,$#*;%1B*-* &-%'$7=*1;*-..%$C()*.1,,-D#$O* 1"P$.7#Q** +%1-O$($O*$B'##'1(*:%1(*,'($*OL$*71*[N* 81DD,$%R*,')57*"$(O'()R*-(O*,$(#'()* $Ä$.7#*v* * d%1"'()*#7%1()*)%-&'7-C1(-,*|$,O#** Z'75*>?%-=*6$?,'($#*;%1B*-..%$C1(*O'#/#* Discs around black holes: a look from aside Disc temperature Discs observed from infinity.