Prof. F. Tombesi
Black Holes and Galaxies
(S3, elective, 6 ECTS)
Learning Outcomes:Fundamental knowledge on the structure of black holes, galaxies and active galactic nuclei, on their properties as sources of electromagnetic radiation, on the selection of statistically significant samples, and on the evolution of the sources in a cosmological framework.
Knowledge and Understanding:
– Detailed knowledge of the structure of accreting black holes, galaxies and active galactic nuclei, of their properties as sources of electromagnetic radiation, and of their cosmic evolution. – Knowledge of the main crietria for the selection of statistically significant samples. – Fair knowledge of the state of the art about black holes, galaxies and active galactic nuclei.
Applying Knowledge and Understanding:– To be able to estimate main physical quantities characteristic of black holes, galaxies and active galactic nuclei on the basis of observational data. – To be able to read and understand recent scientific articles about the physics of extragalactic sources.
PrerequisitesBasic knowledge of general physics and astrophysics.
ProgramWhat is the origin, growth and evolution of black holes, and what is their influence on the surrounding environment, are fundamental open questions in astrophysics. Indeed, supermassive black holes (SMBHs), whose accretion phases are observable in electromagnetic (EM) radiation as active galactic nuclei (AGN), seem to reside at the center of virtually every galaxy in the Universe, and their activity can have impacts on scales ranging from the event horizon up to galaxy clusters. In this class we will describe the physics of black holes; the accretion and ejection processes from stellar-mass to supermassive black holes; the EM appearance of AGN and quasars; AGN feedback in galaxies and galaxy clusters; binary BHs and mergers; gravitational waves (GWs); the cosmological evolution of BHs and galaxies; galactic habitability of exoplanets; major international ground- and space-based astrophysical observatories; multi-messenger extragalactic astrophysics.
1 The observational picture of AGN 1.1 Introduction 1.2 Broad lines, narrow lines, and the big blue bump 1.3 Main components of AGN 1.4 Observational channels 1.4.1 X-ray observations: probing the innermost regions 1.4.2 Highest energies: from gamma-rays to the TeV range
2 Radiative processes 2.1 Scattering of photons 2.1.1 Thomson scattering 2.1.2 Compton scattering 2.1.3 Inverse Compton scattering 2.1.4 Thermal bremsstrahlung 2.1.5 Pair production 2.2 Synchrotron emission 2.2.1 Synchrotron emission of a particle plasma 2.2.2 Synchrotron self-absorption 2.2.3 Synchrotron self-Compton
3 The Central Engine 3.1 The black hole 3.1.1 Approaching a black hole 3.1.2 Evidences for black holes in AGN 3.1.3 Gravitational field near a black hole: the Schwarzschild metric 3.1.4 Rotating black holes: the Kerr metric 3.2 Accretion processes 3.2.1 Accretion basics: Bondi accretion and the Eddington limit 3.2.2 Accretion and viscous dissipation in a thin disk 3.2.3 Accretion in thick disks 3.2.4 Advection-dominated accretion flows 3.3 Photoionization modeling 3.4 Absorption close to a black hole 3.4.1 Torus model 3.4.2 Mass loss in AGN 3.5 Narrow and broad-line regions 3.6 Reverberation mapping: probing the scale of the BLR 3.7 AGN jets: emission, dynamics and morphologies 3.7.1 Raising the jet 3.7.2 Shocks and knots 3.7.3 Superluminal motion
4 AGN Types and Unification 4.1 Seyfert galaxies (Sys) 4.1.1 Optical classification 4.1.2 H II regions 4.1.3 X-ray classification 4.1.4 Narrow-Line Seyfert 1 galaxies (NLSy1s) 4.2 Low-Luminosity AGNs (LLAGNs) 4.3 Ultraluminous X-ray Sources (ULXs) 4.4 Ultraluminous Infrared Galaxies (ULIRGs) 4.5 Radio Galaxies (RGs) 4.6 Quasars (QSOs) 4.6.1 Radio-Quiet Quasars (RQ QSOs) 4.6.2 Radio-Loud Quasars (RL QSOs) 4.6.3 Broad Absorption Line Quasars (BAL QSOs) 4.7 Blazars 4.8 Unification of AGNs 4.8.1 Absorbed vs. unabsorbed AGNs 4.8.2 Radio-loud vs. radio-quiet 4.8.3 Breaking the Unification 4.8.4 Grand unification of black holes in the Universe 4.9 “Transient” AGNs: the case of Tidal Disruption Events (TDEs) 4.10 Dual AGNs and binary SMBHs
5 AGNs through the electromagnetic spectrum 5.1 Radio: probing the central engine 5.2 Infrared: dust near and far 5.3 Optical: where it all began 5.4 UV: the obscured inner disk 5.5 X-rays: absorption, reflection, and relativistic lines 5.5.1 AGNs in the X-ray, from 1965 to the 1990s 5.5.2 Today and future X-ray missions 5.5.3 The X-ray spectrum of AGNs 5.6 Gamma-rays: the blazar dominated sky 5.7 Very High Energies 5.7.1 The high-energy end of the spectrum and astroparticles 5.8 The whole picture: the spectral energy distribution 5.8.1 SED of blazars: a whole different story The one-zone model External Compton scattering 5.8.2 The SED of non-beamed sources The synchrotron branch Dust in the SED The disk component The inverse Compton branch
6 The Environment 6.1 Host galaxies of AGNs 6.1.1 Morphological classification of galaxies 6.1.2 Host galaxy and black hole mass 6.1.3 AGN-host galaxy feedback 6.2 The AGN-Starburst connection 6.2.1 Estimating the Star-Formation Rate 6.2.2 AGN-Starburst feedback 6.3 Galaxy mergers 6.4 AGNs in clusters of galaxies 6.5 AGN feedback and galactic habitable zone
7 Formation, Evolution, and the Ultimate Fate of Black Holes and AGNs 7.1 The first black holes: how did they form? 7.2 Tools to study black hole and AGN evolution 7.2.1 The Number-Flux relation 7.2.2 The V/Vmax test 7.2.3 Luminosity function 7.3 Luminosity functions of AGN 7.4 The Cosmic X-ray Background (CXB)
Description of how the course is conductedClassroom lecture.
Description of the didactic methodsPowerPoint presentations.
Description of the evaluation methodsPresentation of a scientific article by the student. Questions considering the whole teaching program.
Adopted TextbooksLecture Notes • Beckmann & Shrader, Active Galactic Nuclei, Wiley-VCH • Peterson, An introduction to Active Galactic Nuclei, Cambridge University Press
Recommended readingsUpdated literature papers on the topics covered by the course are mentioned during the lectures.