Activity of Supermassive Black Holes
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Activity of Supermassive Black Holes Agnieszka Janiuk, Center for Theoretical Physics, PAS, Warsaw, Poland Supermassive BHs in the Universe ● Episodic activity in active galaxies ● Radio jets, radio structures ● Merging SMBHs ● Tidal disruptions ● Ultra Dwarf galaxies ● Black hole 'archaeology', primordial BHs, unidentified BHs Simple AGN Unification scheme Di Matteo et al. (2014) Active Galaxies I. Episodic Activity 3 1 a cT 4 1 d S H P= − M˙ T 2 H 3 2 r dr Viscous dissipation Radiative losses Advection of energy of energy P 2 2 = H Hydrostatic equilibrium 3G M M˙ F tot= f r P 83 rad Total fux emitted at radius r Pgas Stationary black hole accretion 1D ∂ 1 ∂ 1/2 ∂ 1/ 2 = [3r r ] ∂ t r ∂ r ∂r Conservation of mass and angular momentum dS T =Q −Q dt visc rad Energy equation Time dependent disk Internal instabilities in accretion disk Radiation pressure: Radiatively cooled phase unstable if Prad Prad>Pgas Advection stabilizes P the hot phase gas Partial hydrogen ionization: alpha=0.2 Unstable if 3.5<log T<4 Opacities depend on temperature and density inversely in that region Cycle enhanced if alphahot>alphacold alpha=0.02 Instabilities in black hole accretion flow Radiation pressure instability Qvisc ~Ptot Qvisc~sqrt(Pgas*Ptot) disk stabilized by a wind outflow partial hydrogen ionization instability Janiuk & Czerny, MNRAS, 414, 218 (2011) IGR J17091- Modeling and 3624, analysis : AJ, M. analogue to Grzędzielski, F. GRS Capitanio, S. 1915+105 Bianchi (2015, A&A); see also P. Sukova, M. Grzędzielski, AJ. (2015, submitted to A&A, “Heartbeat arXiv:1506.02526 ) states” in microquasars Observations: figure from Altamirano et al. 2011; BH accretion disk: partial hydrogen ionization The disk is unstable at 3.5<log T<4 K The opacities inversely depend on density and temperature (analogousy to the dwarf-nova stars) Janiuk A., Czerny B., Siemiginowska A., Szczerba R., 2004 Kunert-Bajraszewska M. & Janiuk A., (2011), ApJ, 736, 125 Cyclic behaviour of unstable accretion disk. Simulation with GLobAl Disk InStability code (M. Grzędzielski) Binary Quasar FIRST J164311.3+315618 Kunert-Bajraszewska M. & Janiuk A., (2011) Stabilizing the disk: viscosity fluctuations, modeled as a Markov chain process viscosity with a constant; a ~ 0.1 r ,t = 0 [1r ,t] 0 fluctuating part r ,t =b0 un e is a random variable [-1;1] un=−0.5un−1n 1 r 2 = Timescale of a fluctuation visc H c H = s Spatial scale of a fluctuation See: Lyubarskii 1997; King et al. 2004 Stabilization of outbursts by propagating viscosity fluctuations r ,t =b0 un fluctuating part Janiuk & Misra, A&A, 540, 114 (2012) “Fundamental plane of black holes” The jet power in accretion black holes correlates with their mass. The stabilizing jet effect in AGN can be stronger: we hardly see the radiation pressure instability Merloni et al (2006) Gigahertz-Peak spectrum sources Small sizes of the radiosources are due to their young ages 102 – 104 yrs Statistically we would have too many young sources compared to the mature ones Hypothesis: they are in fact old, but reactivated: Mergers Accretion duty-cycle Fanti et al. 2001 Gigahertz-Peak spectrum sources Model: radiation pressure instability. Outburst durations. • The activity duty cycle timescales are roughly consistent with the sources ages, determined from the kinematics or synchrotron spectra Czerny, Siemiginowska, Janiuk, Nikiel-Wroczyński, Stawarz; 2009, ApJ Activity restart and jet precession in the quasar MERLIN 5 GHz, full-track E 2D-slice from the QSO 1045+352: 3D-simulation of accretion flow misaligned radiostructure Kunert-Bajraszewska M., Janiuk A., Gawroński M., Siemiginowska A., 2010, ApJ Merging Black Hole Binaries Extremely close SMBH Binaries For the binary quasar FIRST J164311.3+315618, its projected separation of this pair is 2 arcs (15 kpc) it is one of the smallest-known separations Below ~ 1kpc, a few systems have been identified and spatiadue tolly resolved. NGC 6240 (Komossa et al. 2003) and NGC 3393 (Fabbiano et al. 2011), based on Chandra spectroscopy. In Optical the source SDSSJ1502+1115 (Woo et al. 2014) The blazar OJ 272, by its semiperiodic variability. Composed of SMBBH on eccentric orbit (Valtonen et al. 2012), with semi-major axis of 0.045 pc. Further orbital shrinkage due to GW emission estimated. Optical variability of the quasar PG 1302−102 suggests its sub-parsec separation (Graham et al. 2015) 1.6 GHz MERLIN radio image SDSS optical image Kunert-Bajraszewska & Janiuk, ApJ, (2011) Komossa & Zenzus, 2015 Komossa & Zenzus, 2015 Binary Black Holes in mergers The “final parsec problem”: ●At separations of 1 pc, the BH binary forms bound pair. It might stall at parsec-scale separations for more than Hubble time (see review by Colpi, 2014) Some key questions: ●When does the accretion process start and how long it lasts? ●How much matter is accreted before and after SMBBH coalescence? ●How much the SMBHs grow in each phase? How much does their spin change during accretion? ●How often are both SMBHs active? ●How efficient is feedback process? ● How efficient is loss of angular momentum due to interactions with gas and stars? ●What is the amplitude of GW recoil? ICM computer cluster www.einsteintoolkit.org Merging black hole pairs Extreme High Mass X-ra Biary: massive star is spun up by the interaction in binary system Examples: Cyg X-3, IC 10 X-1, NGC 300 X-1 Ultimately, the black hole enters massive star's envelope Janiuk, Charzyński & Tidal squeezing triggers the core Bejger, A&A, 560, 25 collapse in the primary (2013) ● Two black holes merge ● Matter accretes on the product ● Jets (possibly dual), accompanied by GW signal ● Recoil of the black hole, speed 200-300 km/s Intergalactic medium, Gamma Ray Bursts Gamma Ray Bursts Prompt emission in Gamma plus afterglow up to IR/Radio bands Relativistic jets from accreting black holes are responsible for GRBs Two classes: Long-soft, black hole is newly born in the collapsing star Short-hard, black hole and neutron star mergers GRB central engine, powered by Blandford- Znajek process: L ~ 1052 erg/s BZ And by neutrino annihilation L ~ 1053 erg/s V Janiuk, Mioduszewski & Mościbrodzka, ApJ, 776, 105 (2013); Janiuk, Yuan, Perna, di Matteo, ApJ, 664, 1011 (2007) Nucleosynthesis and heavy element enrichment Janiuk A., A&A, 568, 105 (2014) ● NASA's Nuclear Spectroscope Telescope Array, or NuSTAR, has, for the first time, imaged the radioactive "guts" of a supernova remnant. The NuSTAR data are blue, and show high-energy X- rays. Yellow shows non- radioactive material detected previously by NASA's Chandra X-ray Observatory in low-energy X-rays. The K computer – named for the Japanese word "kei" ( 京 ?), meaning 10 quadrillion – is a supercomputer manufactured by Fujitsu, currently installed at the RIKEN Advanced Institute for Computational Science campus in Kobe, Japan Supermassive Black Holes. Radio loud quasars Broadband emission from BAL quasars Kunert-Bajraszewska, Katarzyński & Janiuk, A&A, 574, 110 (2015) Broadband emission from BAL quasars Kunert-Bajraszewska, Katarzyński & Janiuk, A&A, 574, 110 (2015) Activity of the Milky Way Flares from Sgr A* Top: 2–8 keV, 2–4 keV, and 4–8 keV Sgr A* light curves in 300 s bins from Chandra ObsID 14392, comprised of zeroth-order and ± first-order counts. Time is measured relative to the observation start: 2012 February 9, 06:17:04 UTC. Each light curve is fit with a constant, two Gaussian distributions (for the precursor flares), and a Gumbel distribution. Middle: hardness ratio of the 4–8 keV/2– 4 keV rates, shown with the hardness ratio from the fits. Bottom: close-up of the bright flare, highlighting its asymmetric profile. Oscillating shocks in the accretion flow Sukova P. & Janiuk A., 2015, MNRAS, 447, 1565 Flares from oscillating shocks ●Numerical simulations of transonic accretion flow hydrodynamics ●Study of the position of critical points and shock front propagation ●Physical parameters: specific energy, specific angular momentum, adiabatic index Sukova & Janiuk, 2015 ●Multidimensional modeling of magnetized flows, work in progress (Sukova et al., in prep.) Tidal Disruptions Tidal disruption process Ultra Compact Galaxies ● Galaxies discovered in the spectroscopic survey of the Virgo Cluster (Mieske et al. 1998) ● Linear sizes below 100 pc 6 8 ● Stellar masses about 10 – 10 M sun ● Dynamical mass-to-light ratios are 50% highre than for stellar populations ● SMBHs expected in their centers may have 10- 15% of the total galaxy mass ● Typically interpreted as tidally stripped nuclei of dwarf galaxies Galaxy M60-UCD1 Ultra compact dwarf galaxy in the Virgo cluster X-ray flux of 1.3 x 1038 erg/s, attributed to the optical center of M60-UCD1 (Luo et al. 2013) Contains a supermassive black hole of about 2.1 x 107 solar masses (Seth et al. 2014) BH constitutes even about 20% of the total galaxy mass It is at a projected distance of only 6.6 kpc from the center of M60 Its radial velocity of 1290 km/s combined with systemic velocity of M60, which is 1117 km/s (Strader et al. 2013), may give a relative tangential velocity of some 240 km/s Artist's movie about how UCD1 has been formed http://www.spacetelescope.org/videos/heic1419a/ Archaeology. Unidentified black holes This all-sky view from Fermi reveals bright emission in the plane of the Milky Way (center), bright pulsars and super-massive black holes. Credit: NASA/DOE/International LAT Team The Fermi-LAT catalogue contains still over 300 of unidentified sources. They have no counterparts in other bands of electromagnetic spectrum. New interpretation: quasi-star jets Quasi-stars: a intermadiate redshifts. led to formation of SMBHs in galactic nuclei. They should have different observable properties than identified Fermi sources: (Predictive power of theory) Quasi stars are comparable in number with unidentified Fermi sources (Post-dictive power of theory) Optical brightness, 20-21 mag, may help identify the sources in SDSS or WISE surveys (Further test of theory) Czerny, Janiuk, Sikora, Lasota; ApJ Letters, 755:L15 (2012) Archaeology.