1. High accretion rates, tidal disruption flares and recoils: recent results on supermassive black holes Introduction Highly accreting AGN on the M- sigma relation Flares from tidally disrupted stars Recoiling black holes Peking University, 10. April 2008 Stefanie Komossa MPE MPE

2. BHs in astrophysical context: how frequent are SMBHs, do they reside in all galaxies ? what is the distribution of their masses & spins ? when & how did most SMBHs form ? before, simultaneous with, after galaxies ? why are SMBH and galaxy bulge properties so closely linked ? how do SMBHs grow ? accretion, BH-BH merging, stellar disruptions; timescales ? why are some SMBHs `dark´ ? how long do the phases of accretion activity last, what is the relation between different types of „Active Galaxies“ (quasars – Seyfert galaxies), etc.,... Supermassive Black Holes (SMBHs) – key questions

3. the SMBH at our Galactic Center stars in Keplerian orbits around central black hole  high-precision measurement of BH mass: M = 4  2 a 3 /GP 2 = 3.6   M sun periastron of closest encounter: ~2000 R S (star S2, period: 15 yrs) constraints on mass/volume very tight only possible in our own G.C. ; in ~30 nearby galaxies we can still resolve the „sphere of influence“ of the SMBH [e.g., Schödel & 02, 03, Genzel & 03, Ghez & 03, 05, Eisenhauer & 05; Boganoff & 03, Aschenbach & 04, Eckart & 06, Krabbe & 06, Belanger & 06; Genzel &Karas 07]

4. the M BH -  relation  implies close link between BH and galaxy formation & evolution models: regulation of bulge- growth due to feedback from active BH and/or star formation correlation between black hole mass, M BH, and bulge stellar velocity dispersion,  , M BH /    sun  = 1.7   /  0   (FF05) [M-  : Ferrarese & Merritt 00, Gebhardt & 00, MF01, Tremaine & 02, Ferrarese & Ford 05] [models: e.g., Silk & Rees 98, Burkert & Silk 01, Haehnelt 03, Springel et al. 05, Li et al. 07,...]

5. the M BH -  relation do all types of galaxies, at all times, follow the M-   relation ? how do objects ‚move onto‘ the relation ?  check nearby AGN, accreting at high rates; i.e., rapidly growing their BHs [M-  : Ferrarese & Merritt 00, Gebhardt & 00, MF01, Tremaine & 02, Ferrarese & Ford 05] [models: e.g., Silk & Rees 98, Burkert & Silk 01, Haehnelt 03, Springel et al. 05, Li et al. 07,...] seen at hi z ??

6. Active Galactic Nuclei (AGN) most luminous long-lived objects in the universe powered by accretion onto supermassive black holes (SMBH) strict „unified model“: key difference between AGN types (Sy1, Sy2,....) due to viewing angle effects emission lines provide a wealth of information on the physical conditions in the cores of AGN

7. M BH and  measurements in AGN in AGN, we have an independent way to measure BH masses from „reverberation mapping“ of the BLR,  R BLR -L relation [e.g., Kaspi et al. 2005, Peterson 2007] do we also have a way to measure   ? Not really, AGN conti bright; stellar absorption features often superposed by bright conti & emission-complexes [Nelson & Whittle 96, Nelson 2000]  use gaseous kinematics, traced by emission-lines, instead. Indeed, FWHM([OIII]) and  * correlate - after removing galaxies with strong kpc-scale radio sources.

8. AGN on the M BH –  relation what about ‚extreme‘ AGN : Narrow-line Seyfert 1 galaxies - defined as AGN with narrow BLR Balmer lines ( FWHM Hb < 2000 km/s ), weak [OIII]/H  emission - at one extreme end of AGN correlation space (strongest FeII, steepest X-ray spectra, most rapid X-ray var.,...)  NLS1s are AGN with low BH masses & high Eddington rates L/L edd  objects rapidly growing their BHs, in the local universe  do they follow the M-  relation ? method widely applied, up to high z [e.g., Shields & 03, Boroson 03, Greene & Ho 05, Salviander & 07, Netzer & 07,... ] nearby ‚normal‘ AGN : agree with M BH –    relation if   is used as substitue for  

9. original claim: NLS1s are OFF M BH –   relation few real   measurements (Botte 05: „on“; Zhou 06: „off“) [Mathur et al. 01, Wang & Lu 01, Wandel 02, Grupe & Mathur 04, Bian & Zhao 04,06, Botte & 04, 05, Barth & 05, Mathur & Grupe 05a,b, Greene & Ho 05, Zhou & 06, Ryan & 07, Watson & 07, Komossa & Xu 07] NLS1s on the M BH –  [OIII] planes  how reliable is [OIII] as substitute for stellar velocity dispersion ?  influence of outflows ?

10. [Komossa & Xu 07] NLS1s on the M BH –    relation new analysis, based on sample of SDSS-NLS1s, plus BLS1 comparison sample; using several NLR emission lines (& decomposing complex [OIII] profile) on NLS1s on M BH -   SII] follow  NLS1s follow the M BH -  [SII] relation  and they follow the M BH -  [OIII] relation, if objects with outflows in [OIII] are removed  remaining scatter in the relation does not systematically depend on [OIII] strength, FeII, density, M i, L/L edd ?

11. summary: NLS1 galaxies do follow M- , if objects dominated by outflows)* are removed  they evolve along the M-  relation BH mass increases by fact. 10 within   yr (L~L edd ), if BH keeps growing NLS1 hosts: no mergers, but perhaps excess of bars  either acc. short-lived, or else secular processes at work to adjust host properties, keeping them on the relation NLS1s on the M BH –    relation )* also occur in BLS1s (  relevant for all studies which involve [OIII] lines as surrogate for  * ), but less often

12. extreme outflows in AGN: on the nature of [OIII] „blue outliers“ what causes the „blue outliers“, which have their whole [OIII] profile blueshifted, by up to several 100 km/s ? [Komossa, Xu, Zhou, Storchi- Bergmann, Binette 08]

13. on the nature of [OIII] „blue outliers“ they show evidence for extreme outflows up to 1000 km/s affecting the (hi-ion BLR), CLR, and large parts of the NLR - while the outer NLR is quiescent driving mechanism is still being investigated - radiation pressure, cloud-entrainment in jets, thermal winds high L/L edd, & pole-on view into an outflow ? is feedback due to outflows at work ? follow-up HST imaging: search for mergers a la Springel et al. / or bars [Komossa, Xu, Zhou, Storchi- Bergmann, Binette 08]

14. Tidal disruption of stars by SMBHs stellar distortion & disruption extreme squeezing of star  ign. of nucl. burning collision of unbound gas with ISM, shocks (?) accretion phase(s): luminous flare of radiation [artist‘s view; NASA/ CXC/ M. Weiss/ Komossa & 04 ]

15. giant-amplitude X-ray outbursts from non-active galaxies [e.g., Komossa & Bade 99, Halpern & 04, Komossa et al. 04, 08] initial flare of X-rays with L x at least sev. 10  erg/s from otherwise normal, non-active galaxies still detected with Chandra ~10 yrs after the initial burst fast rise, slow decline, consistent with predicted t  law amplitudes of variability: up to factor 6000 disruption of solar-type star enough to power the flare collective lightcurve, measured with ROSAT, XMM and Chandra

16. NLS1 galaxies do follow the M –  relation of BL-AGN and normal galaxies ( large scatter, as usual ), if [SII], [OIII] core are used to measure  if BHs keep accreting for long time, host properties must adjust accordingly to keep them on M–  location of galaxies on the M–  plane does not systematically depend on emi-line strength, n NLR, L/L edd,... except: lines with systematic blueshifts in [OIII] have anomaleously broad profiles  outflows dominate  not suitable for   measurements ( their non-removal was cause for previous claims that NLS1s deviate; all samples making use of [OIII] have to remove ‚blue outliers‘ ) these [OIII] outliers are of independent interest because of their extreme large –scale outflows (  constraints on mechanisms to drive AGN winds on large scales, mechanisms of cloud entrainment ?) Summary- part 1

17. Summary – part 2 we have detected the emission-line light-echo & low-E tail (NUV, opt, NIR) of a high-E outburst (EUV, X) of huge amplitude likely caused by stellar tidal disruption such events are rare; provide rare chance & very efficient way to `map´ physical conditions in circum-nuclear gas (e.g., inner wall of dusty torus) large-scale spectroscopic surveys, like SDSS, well suited to find more `light- echos´, while future X-ray all-sky surveys will detect the actual X-ray flares