Active Galactic Nuclei: Laboratory for Gravitational Physics

Talk presented at the 29th Midwest Relativity Meeting, Grand Valley State University, Grand Rapids, MI, USA, October 2019

Transcript

1. Active Galactic Nuclei Laboratory for Gravitational Physics Image Credit: NASA/JPL-Caltech Image Credit: NASA/JPL-Caltech Ashkbiz Danehkar Department of Astronomy, University of Michigan danehkar@umich.edu The 29th Midwest Relativity Meeting, Grand Rapids, Michigan, USA, October 4th, 2019
2. 10/04/2019 Midwest Relativity Meeting 2 Gravity Timeline 1687: Newtonian gravity 1915: General Relativity 1960-1975: golden age of GR (Kip Throne 1995) – Cambridge (Sciama’s group) – Hamburg GR group (Jordan) – Potsdam AEI (Ehlers’ group) – Syracuse (Bergmann’s grp) – UT Austin (Schild’s group) – ... local interaction (Einstein field equations) non-local long-range interaction (Binanchi identities) Trumper 1964, Hawking 1966, Ellis 1971
3. 10/04/2019 Midwest Relativity Meeting 3 Gravity Timeline 1992-present: golden age of cosmology (Alan Guth 2001) 2019: EHT imaging of SMBH in M87 2016: LIGO detection of gravitational waves • (Weiss+Throne+Barich 2017) 1995: acceleration expansion of the universe (Perlmutter+Schmidt+Riess 2011) 1974: Test of GR in a binary pulsar (Hulse+Taylor 1993)
4. 10/04/2019 Midwest Relativity Meeting 4 Active Galactic Nuclei (AGN) 2019: EHT imaging of SMBH in M87 First Image of a Supermassive Black Hole Credit: Science History Images / Alamy Stock Photo
5. 10/04/2019 Midwest Relativity Meeting 5 Active Galactic Nuclei (AGN) X-ray Observations of AGN (1999-present) Chandra X-ray Observatory (1999-present) XMM-Newton, X-ray Multi-Mirror Mission (2000-present) NuSTAR, Nuclear Spectroscopic Telescope Array (2012-present) Gierlinski + 1999 Lonanov 2007 Credit: Roen Kelly @ Astronomy
6. 10/04/2019 Midwest Relativity Meeting 6 Active Galactic Nuclei (AGN) AGN Unified Model (radio-loud & -quiet AGN, Seyfert I & II Galaxies) Beckmann & Shrader 2012, Active Galactic Nuclei Unified Models for AFNs Antonucci, ARA&A, 1993, 31, 473 Unified Schemes for AGNs Megan Urry & Padovani, 1995, PASP, 107, 803 (Bernie Fanaroff & Julia Riley 1974) AGN Unified Model • Radio-Quiet AGN  Seyfert I (BLR+NLR, compact outflows)  Seyfert II (NLR) • Radio-Loud AGN  FR I (compact radio jets)  FR II (extended radio jets)  Blazar (relativistic beams) (Carl Seyfert 1942)
7. 10/04/2019 Midwest Relativity Meeting 7 Active Galactic Nuclei (AGN) Dermer & Giebles 2016 AGN Classification (radio-loud & -quiet AGN, Seyfert I & II Galaxies) Blandford, Netzer, Woltjer 1990, Active Galactic Nuclei
8. 10/04/2019 Midwest Relativity Meeting 8 Ultra-fast Outflow in AGN Detection of relativistic outflows in X-ray • Seyfert I PG 1211+143 Ionized outflow at -0.06c and -0.11 c Danehkar + 2018 Pounds + 2003,2006,2009 Ionized outflow at -0.06c
9. 10/04/2019 Midwest Relativity Meeting 9 Ultra-fast Outflow in AGN Detection of relativistic outflows in X-ray • Seyfert I PDS 456 Ionized outflow at -0.24c and -0.48 c Biossay-Malaquin, Danehkar + 2019
10. 10/04/2019 Midwest Relativity Meeting 10 Ultra-fast Outflow in AGN Detection of relativistic outflows in X-ray Cappi 2006
11. 10/04/2019 Midwest Relativity Meeting 11 Ultra-fast Outflow in AGN Correlation between outflow kinematics and physical conditions Tombesi + 2013 (Ultra-fast outflows) (Warm Absorbers)
12. 10/04/2019 Midwest Relativity Meeting 12 Ultra-fast Outflow in AGN X-ray Ionized Outflows in AGN Ionization parameter Gas density Radius Column density Shell thickness Outflow velocity Luminosity (0.0136- 13.6 keV) King & Pounds 2015; XMM-Newton & Suzaku (42 radio-quiet, Tombesi et al 2011; 51 AGN, Gofford et al. 2013) BH mass
13. 10/04/2019 Midwest Relativity Meeting 13 Ultra-fast Outflow in AGN Theories for Relativistic Outflows in AGN • strong magnetic field in accretion flow/disk of rotating BH – Blandford-Znajek process (1977) for strong jets from flow – Blandford-Payne process (1982) for slow winds from disk • frame dragging (gravitomagnetism indirectly) – Penrose process (1971) – Kerr spacetime of rotating BH – extracting black-hole rotational energy • frame dragging + magnetic field (e.g. Narayan & Quataert 2005) • gravitomagnetism (directly)? Frame dragging+magnetic (Narayan & Quataert 2005) Blandford-Znajek process (Thorne 1995)
14. 10/04/2019 Midwest Relativity Meeting 14 Supermassive Black Hole Spin Black Hole Spin Measurement (see Brenneman 2013) • Thermal Continuum Fitting (UV observation) – stellar-mass black hole – AGN (may problematic due to UV absorption lines!) • Inner Disk Reflection Modeling – AGN (X-ray) • High Frequency Quasi-Periodic Oscillations – AGN + stellar-mass black hole (fully not developed) • X-ray Polarimetry – Need sensitive X-ray polarimter (not available now!) • Imaging the Event Horizon Shadow – Need Very Long Baseline Interferometry (in development) – Suitable only for Sgr A* and M87 a = J c / G M2 (a: BH spin, J: angular momentum, M: BH mass, G: gravitational constant, c: speed of light)
15. 10/04/2019 Midwest Relativity Meeting 15 Supermassive Black Hole Spin Relativistically broadened Kα iron line (6.4 keV) Compton hump (> 10keV) Black Hole Spin Measurement from X-ray a = - 1 a = 0 a = 1 Image credit: NASA/JPL-Caltech
16. 10/04/2019 Midwest Relativity Meeting 16 Supermassive Black Hole Spin BH Spin from Reflection Modeling • kerrconv (Brenneman & Reynold 2006) • relline (Dauser + 2010) • xillver (Garcia + 2010,11,13) • relxill (Garcia + 2014) Dauser & Garcia + 2014
17. 10/04/2019 Midwest Relativity Meeting 17 Supermassive Black Hole Mass BH Mass from Reverberation Mapping Technique (Kaspi + 2000) • Variation in light curves of broad emission line region (BLR) in Seyfert I AGN • Time delay in variation of BLR luminosity (Hb 4861A) relative to variation of accretion disk luminosity (continuum 5100A) www.techfreaq.de Bentz + 2006
18. 10/04/2019 Midwest Relativity Meeting 18 SMBH Spin Implication Black Hole Spin Implication for a Unified AGN Model? Garofalo + 2010 Beckmann & Shrader 2012, Active Galactic Nuclei AGN Unified Model - Radio-Quiet AGN: Seyfert I, Seyfert II - Radio-Loud AGN: FR I, FR II (extended radio jets)
19. 10/04/2019 Midwest Relativity Meeting 19 SMBH Spin Implication Black Hole Spin Implication for a Unified AGN Model? Danehkar +
20. 10/04/2019 Midwest Relativity Meeting 20 Future Direction for X-ray Astronomy • XRISM, X-Ray Imaging and Spectroscopy Mission (2022) – Japan Aerospace Exploration Agency (JAXA) – Replacement for Hitomi, ASTRO-H (2016, failed) • ATHENA, Advanced Telescope for High Energy Astrophysics (2031) – European Space Agency (ESA) • Lynx X-ray Observatory (proposed 2035) – National Aeronautics and Space Administration (NASA) • Arcus X-ray observatory (proposed 2023) – NASA
21. 10/04/2019 Midwest Relativity Meeting 21 Proposed Direction for Numerical GR • Finite-difference Time-domain (FDTD; 1980) • Discontinuous Time-domain Method (FETD; 2000) • Finite Element Method (FEM; 1973) • Finite Integration Technique (FIT, 1977) • …. ? For Maxwell EM equations, there are several numerical methods: For Einstein field equations (local gravitational interaction), there are several numerical methods (see review by Font 2003 for numerical GR; Fornt 2008 for GR+MHD) For example, for Bianchi dynamical formulas of non-local (Weyl) gravitational fields: Newtonian Tidal force Non-Newtonian effect Gravitational waves shear induction? computational hydrodynamics simulation not fully developed angular momentum • Finite Difference Method (FDM; 1988) • Smoothed Particle Hydrodynamics (SPH; 1977) • Spectral Methods (1988) • Flow Field-dependent Variation Method (FDV; 2002) • …. One of reference books for mathematics of Weyl fields
22. 10/04/2019 Midwest Relativity Meeting 22 Summary Implication of Supermassive Black Hole Angular Momentum for AGN Outflows?  Relativistic Outflows in AGN measured from – blue-shifted highly-ionized absorption lines in X-ray spectra  AGN Outflow Physical conditions from – photo-ionization modeling of absorbers  Black Hole Spin measured from – relativistic Fe Kα line (6.4 keV) – Compton hump (> 10keV)  Black Hole Mass measured from – time delay in BLR vs. disk light curves in Seyfert I AGN (Reverberation-mapping)  Physical Mechanism behind relativistic outflows in AGN? – Need for larger sample and future X-ray observations (XRISM 2022, ATHENA 2031, Lynx 2035) – Future developments in numerical methods & simulations of GR hydrodynamics Credit: Roen Kelly @ Astronomy
23. Image Credit: NASA/JPL-Caltech Image Credit: NASA/JPL-Caltech Thank you for your attention Thank you for your attention