Paths to a Unified AGN Outflow Model via Computational Relativity Ashkbiz Danehkar, Postdoc Department of Astronomy, University of Michigan [email protected] Challenges and Innovations in Computational Astrophysics - II, November 20, 2020 Image Credit: J. Bergeron, Sky & Telescope Magazine Image Credit: J. Bergeron, Sky & Telescope Magazine 

20/11/2020 Computational Astrophysics II 2 Outline  Observational Background  AGN Classification  Ultra-Fast Outflow (UFO)  Evidence for a Unified AGN Outflow Model  Implication of Black Hole Spins  Black Hole Spin Surveys  Relativistically broadened Fluorescence K-shell Iron Line  Compton continuum above 7 keV  Relativistic Reflection Model (relxill + xillver)  Numerical Relativity  Visualization of Gravitational Physical Lines: Tendex and Vortex  Einstein Cactus Computational Toolkit 

20/11/2020 Computational Astrophysics II 3 AGN Classification Observational Background AGN Unified Model (radio-loud & -quiet AGN, Seyfert I & II Galaxies) Beckmann & Shrader 2012, Active Galactic Nuclei Unified Models for AGNs 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) 

20/11/2020 Computational Astrophysics II 4 Ultra-fast Outflows Disk Black- body Hot Corona Warm Absorbers K-shell Iron Beckmann & Shrader 2012 Risaliti & Elvis 2004 (bbody + powerlaw + ∑ emis) x ∏ abs 

20/11/2020 Computational Astrophysics II 5 Evidence for Unified AGN Outflow Correlation between outflow kinematics and physical conditions Tombesi + 2013 (Ultra-fast outflows) (Warm Absorbers) 

20/11/2020 Computational Astrophysics II 6 Problems Radio-quiet and radio-loud AGN Garofalo + 2010 ● Radio-quiet AGN – Compact Outflows – Weak Radio Source ● Radio-loud AGN – Extended Jets – Strong Radio Source – Typically in elliptical massive galaxies evolved from recent mergers (binary SMBH?) 

20/11/2020 Computational Astrophysics II 7 Observational Background AGN Classification: Radio-loud & Radio-quiet AGN Dermer & Giebles 2016 

20/11/2020 Computational Astrophysics II 8 Implication of Black Hole Spins Correlation between SMBH Angular Momentum with Uktra-fast Outflows Danehkar + 

20/11/2020 Computational Astrophysics II 9 Measurements of Black Hole Spins 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) 

20/11/2020 Computational Astrophysics II 10 Measurements of Black Hole Spins 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 

20/11/2020 Computational Astrophysics II 11 Measurements of Black Hole Spins BH Spin from Reflection Modeling ● kerrconv (Brenneman & Reynold 2006) ● relline (Dauser + 2010) ● xillver (Garcia + 2010,11,13) ● relxill (Garcia + 2014) Dauser & Garcia + 2014 

20/11/2020 Computational Astrophysics II 12 Supermassive Black Hole Spin 

20/11/2020 Computational Astrophysics II 13 Numerical Relativity Weyl (Vacuum Riemann) Tensor Einstein’s 70th birthday, Institute for Advanced Study, 1949 Weyl, Mathematische Zeitschrift, 2, 384, 1918 

20/11/2020 Computational Astrophysics II 14 Numerical Relativity Gravitoelectric and Gravitomagnetic Tensors ● Gravitoelectric & Gravitomagnetic fields – Names coined by Kip Thorne (IAU, 97, 255, 1982) – Thorne et al. Black holes: The membrane paradigm (Yale University, 1986) ● Gravitoelectric Tensor – Newtonian Tidal Force ● Gravitomagnetic Tensor – Frame-dragging vortex & Gravitational Waves ● Bianchi Identities – Constraints for gravitoelectric & gravitomagnetic (see e.g. Relativistic Cosmology, Ellis, Maartens, & MacCallum, Cambridge, 2012) Kip Thorne’s 60th birthday, Caltech, 2000 

20/11/2020 Computational Astrophysics II 15 Numerical Relativity Tendex and Vortex Lines ● Visualization of Gravitoelectric & Gravitomagnetic tensors – Nichols et al. PRD 84, 124012, 2011; PRD 86, 104028, 2012 ● Tidal Tendex Line – Tendex coined by David Nichols (tendere: ‘to stretch’) – integral curves of eigenvectors of gravitoeletric tensor – Owen el al. PRL 106, 151101, 2011 – Zhang et al. PRD 86, 084049, 2012 ● Frame-dragging Vortex Line – integral curves of eigenvectors of gravitomagnetic tensor eigenvector eigenvalue eigenvector eigenvalue Owen el al. PRL 106, 151101, 2011 

20/11/2020 Computational Astrophysics II 16 Numerical Relativity Tendex and Vortex Lines of Slowly Spinning SMBH Danehkar, IJMPD, 2020, arXiv:2006.13287 [gr-qc] ● Visualization of Eab & Hab around a slow Kerr BH – slow Kerr metric (Zhang et al. PRD 86, 084049, 2012) – gravitoelectric tensor – gravitomagnetic tensor (Zhang et al. PRD 86, 084049, 2012) 

20/11/2020 Computational Astrophysics II 17 Numerical Relativity Tendex and Vortex Lines of Fast Spinning BH ● Visualization of Eab & Hab around a fast Kerr BH Tidal Tendex Line Frame-dragging Vortex Line Zhang et al. PRD 86, 084049, 2012 

20/11/2020 Computational Astrophysics II 18 Numerical Relativity Tendex and Vortex Lines of Merging Binary BH ● Visualization of Eab & Hab around binary BHs Tidal Tendex Line Frame-dragging Vortex Line ● Spectral Einstein Code (SpEC) – https://www.black-holes.org/code/SpEC.html – SpEC is not publicity available ● New version: SpECTRE – https://github.com/sxs-collaboration/spectre – SpECTRE is still under development by the SXS (Simulating eXtreme Spacetimes) Collaboration, and not yet ready – Updates on SpECTRE code: https://icerm.brown.edu/programs/sp-f20/w3/ (see talk, Oct 28) Owen el al. PRL 106, 151101, 2011 

20/11/2020 Computational Astrophysics II 19 Numerical Relativity Gravitational Waves ● Visualization of Eab & Hab around binary BHs – Gravitational Wave Simulations by SpEC Owen el al. PRL 106, 151101, 2011 LIGO detection of gravitational waves, 2016 

20/11/2020 Computational Astrophysics II 20 Numerical Relativity Einstein Cactus Computational Toolkit ● The Einstein Toolkit (https://einsteintoolkit.org/) – Cactus Thorns (http://svn.einsteintoolkit.org/cactus/) – Recent Tutorial: https://icerm.brown.edu/programs/sp-f20/w1/ ● Einstein Toolkit Thorn: EinsteinAnalysis/WeylScal4 – calculates Weyl scalars in the Einstein Toolkit – converted to Thorn using Kranc (http://kranccode.org/) ● New Module for gravitoelectric and gravitomagnetic tensors in the Einstein Toolkit – can be made by Mathemtica scripts and converted to Thorn using Kranc ● Kranc: Mathematica program turns tensorial equations into a thorn for the Cactus Computational Toolkit transverse wave component for GW simulations of mergers 

20/11/2020 Computational Astrophysics II 21 Summary Unified AGN Outflow Model via BH Spin Survey & Numerical Relativity ● Observational Background – Observational Evidence for a Unified AGN Outflow Model – Possible correlation between SMBH angular momentum and AGN outflows – Physical mechanism behind radio-loud AGN: binary SMBH in radio-loud? ● Black Hole Spin Surveys  Relativistically broadened Fluorescence Iron Line + Compton continuum  Relativistic Reflection Model (relxill + xillver) ● Numerical Relativity – Gravitoelectric and Gravitiomagnetic tensors visualized using their Tidal Tendex and Frame-dragging Vortex Lines. – Visualization of Tendex and Vortex lines for exact solutions and binary BHs are very complex, but can be done using a new module made by either Kranc or NRPy+ for the Einstein Toolkit. These simulations are computationally expensive (need HPC) 

20/11/2020 Computational Astrophysics II 22 Image Credit: J. Bergeron, Sky & Telescope Magazine Image Credit: J. Bergeron, Sky & Telescope Magazine Thank you for your attention Thank you for your attention