SUMMARY PROBING STRONG GRAVITY IN AGN Kirpal Nandra Imperial College London

PROBING STRONG GRAVITY The Promise The Probes The Progress The Problems The Prospects Probably… Paul Reviews Observations (and Theory)

THE PROMISE What are the processes close to the event horizon? Are black holes in AGN spinning? How does BH spin evolve on the Cosmic Scale? How does matter behave in the strong field? Does it obey the predictions of GR?

THE PROBES Broad emission lines Narrow emission lines Narrow absorption lines Variability/reverb. Broadband/disk/reflection spectra Polarimetry Binary Black Holes Microlensing (Zoghbi, de Marco, Ponti, Goosmann) (Iwasawa, Ballantyne, Guainazzi, de la Calle, Svoboda, Miniutti) (Cappi, Reeves,) (Dovciak) (Laor, Walton) (Cappi) (Komossa, Liu) NOBODY! + Nikolajuk: TBC

PROBES: MICROLENSING RX J Chartas et al Dai et al MICROLENSING! Direct measurement of size of emission region: X-rays from 10 R g (Optical 70 R g )

THE PROGRESS

Risaliti et al NGC1365 Mrk 509 (long-look, 200ks) MC et al., 2009 Dadina et al. ‘05 Obs1 Obs2 Obs3 Variability allows to place limits on location, mass, etc. (See also Krongold et al on NGC4051) Cappi PROGRESS: INFLOWS/OUTFLOWS

PROGRESS: HOTSPOTS Turner et al. 2005Iwasawa et al Cappi, Iwasawa, Reeves, De Marco

PROGRESS: THE INNER FLOW Iwasawa Nikolajuk

PROGRESS: BROAD LINES 45% of XMM-Newton Seyfert sample with >30,000 counts Nandra et al. (2007) De La Calle, Guainazzi

PROGRESS: BROAD LINES Zoghbi

If η implies a * Fanidakis et al. arXiv: PROGRESS: SPIN MEASUREMENT Laor: disk continuum fitting

PROGREES: SPIN MEASUREMENT Miniutti: broad emission lines SWIFT J1247 Fairall-9 Implications for black hole accretion/merger history through cosmic time (also Ballantyne)

PROGRESS: STRONG GRAVITY Iwasawa Walton Svoboda

THE PROBLEMS Broad lines Predicted to be universal, but not always observed Degenerate with complex absorption Lines are much weaker than we might have hoped Sometimes variable, sometimes now Narrow lines NOT predicted unless extreme anisotropic effects. Limited statistical significance (Vaughan & Uttley) “Spallation” of Fe Non-repeatable observations -> cannot test models Should be transient (Kepler timescale) – is this too convenient? QPOs Finally one decent AGN example (RE 1034; Middleton) Ooops it went away (Middleton) Which QPO to associate with GBHC? Interpretation in GBHC not clear despite vastly better data Overall, two major problems: 1)Repeatability of observations 2)Prediction and testing of models

PROBLEMS: BROAD LINES Zoghbi Absorption highly unlikely to be sole explanation, but details (e.g. spin) very hard to disentangle

K. Nandra: broad lines in AGN PROBLEMS: BROAD LINES Disk line upper limits typically eV Criteria: <99% significance for blurred reflection 12 total: IC4329A (1) NGC 5506(1), NGC 5548(1) NGC 7469(1) 30% of Sample Why are broad lines absent? (Almost) unavoidable prediction of accreting systems… Ionization, Fe abundance, Extreme blurring?

Ignacio de la Calle 16 February PROBLEMS: S/N RATIO De la Calle

PROBLEMS: NARROW FEATURES Lines statistical significance? (transient features, number of trials in time and energy, etc…) Identifications of edges/lines energies? (Kallman et al. 2005, Kaspi et al. for PG1211) Local “contamination”? (PDS456 at risk? McKernan et al. ’04, ‘05 ) Publication bias? Only positive detection, low signif., Vaughan & Uttley ‘08 ) cz (km/s) Outflow v (km/s) Solutions: Large Samples, Systematic analysis: Cappi, de Marco, de la Calle, Ponti

Strong narrow K  line at 6.4 keV. Constant flux over 3 years. However redshifted but relatively narrow line emission is observed at 5.4 keV and 5.9 keV in 2005 low state. Obs 1 vs Obs2 PROBLEMS: NARROW LINES Reeves

PROBLEMS: NARROW LINES SuzakuAll XMM co-add Mostly S. Vaughan 5.4 keV If 5.4 keV is real, it is variable (thus not spallation) Reeves

PROBLEMS: LINE VARIABILITY Bhayani & Nandra (2010) Variability key to break degeneracies: Iwasawa, Zoghbi, Reeves, de Marco, Ponti, Goosmann BUT… source behaviour not predictable with current models

PROSPECTS: REVERBERATION Zoghbi Reeves

PROSPECTS: POLARIZATION Dovciak X-ray polarimetry: a new window to be opened by GEMS, NHXM, IXO

PROSPECTS: BH SPIN ASTRO-H: First high resolution, high throughput spectroscopy at 6 keV IXO XMS NGC ks MCG ks IXO IXO: ULTRA-HIGH THROUGHPUT IXO ASTRO-H

PROSPECTS: TRACING HOTSPOTS IXO: high throughput Flux constraint ~20% 400s exposure: 1/10 t Keplerian at 6 r g C. Reynolds

PROSPECTS: TESTING GR? GR correct  =  =0.0 (GR) Johanssen & Psaltis (2009) Testing the no-hair theorem  =0 C. Reynolds

PROGNOSIS Strong gravity effects in AGN can be probed For example,  lensing shows X-rays arise within ~10 Rg Major issues: Model degeneracies Unrepeatable observations Lack of testable model framework Major progress Large samples, systematic analysis Variability studies, reverberation Huge future potential High resolution spectroscopy High throughput spectroscopy Polarimetry See you in Progue 2020! Promising Prospects for Proactive Promotion of Proposed Projects IXO