First cycle
degree courses
Second cycle
degree courses
Single cycle
degree courses
School of Science
ASTRONOMY
Course unit
HIGH ENERGY ASTROPHYSICS
SCN1032610, A.A. 2017/18

Information concerning the students who enrolled in A.Y. 2016/17

Information on the course unit
Degree course Second cycle degree in
ASTRONOMY
SC1173, Degree course structure A.Y. 2010/11, A.Y. 2017/18
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Degree course track ASTRONOMIA [001PD]
Number of ECTS credits allocated 6.0
Type of assessment Mark
Course unit English denomination HIGH ENERGY ASTROPHYSICS
Website of the academic structure http://astronomia.scienze.unipd.it/2017/laurea_magistrale
Department of reference Department of Physics and Astronomy
Mandatory attendance
Language of instruction English
Branch PADOVA
Single Course unit The Course unit can be attended under the option Single Course unit attendance
Optional Course unit The Course unit can be chosen as Optional Course unit

Lecturers
Teacher in charge ALBERTO FRANCESCHINI FIS/05

ECTS: details
Type Scientific-Disciplinary Sector Credits allocated
Core courses FIS/05 Astronomy and Astrophysics 6.0

Mode of delivery (when and how)
Period First semester
Year 2nd Year
Teaching method frontal

Organisation of didactics
Type of hours Credits Hours of
teaching
Hours of
Individual study
Shifts
Lecture 6.0 48 102.0 No turn

Calendar
Start of activities 02/10/2017
End of activities 19/01/2018

Syllabus
Prerequisites: The mandatory courses of 1st year of Laurea Magistrale in Astronomia
Target skills and knowledge: Extended knowlwdge of a vast field of astrophysics, both the theoretical part and the observational fundations.
Examination methods: Oral discussion
Assessment criteria: Proven knowledge of the topics listed below and, particularly, ability to discuss the connections of the various parts.
Course unit contents: FUNDAMENTALS OF CLASSICAL ELECTRODYNAMICS. Basic formulae of electro-magnetism in the classical limit.Electromagnetic waves. The relationship of electric charges and the radiation fields (radiations from moving charges, Lienard-Wiekert potentials, fundamental equation,Larmor,dipole emission,multi-polar contributions,the radiation spectrum.
BREHMSSTRALUNG RADIATION. The classical limit,electric dipole contribution.The Gaunt factor.Thermal Bremsstrahlung.Plasma cooling by free-free emission.Radiative transfer and Bremsstrahlung self-absorption.Relativistic and non-thermal Bremsstrahlung. Applications of thermal free-free emissions by astrophysical plasmas.
GAS DYNAMICS AND PLASMA EFFECTS. Fundamentals of hydrodynamics. General equations and conservation laws.Adiabatic and isothermal stationary flows.Sound waves.Particle collisions in plasmas. Momentum transfer among particles:viscosity.Energy transfer and heat conduction.Shock waves. Effects of magnetic field.
HOT PLASMAS IN GALAXIES AND CLUSTERS OF GALAXIES.Fundamental physical parameters.Thermalization timescales.Heat conduction. Magnetic field effects.Ionization mechanisms.Collisional ionization.Line emissions.Metal abundances in the plasma.Models of plasma distribution.Cooling and heating mechanisms.Origin, astrophysical and cosmological significance of the IC plasma.
SYNCHROTRON RADIATION.Charges in magnetic fields.Total synchrotron emitted power.Aberration, beaming, angular distribution of radiation.Synchrotron spectrum of a single pulse and its spectrum.The transition from the cyclotron to the synchrotron spectrum.Emission by a non-thermal electron distribution.The full treatment. Synchrotron self-absorption and spectral cutoffs.Synchrotron polarization. Limits of validity of our treatment.Electron energy losses and synchrotron spectral evolution.Radio-galaxies and their synchrotron emission. Energetics of the synchrotron emission by radio galaxies. Radio-Quiet Active Nuclei:Quasars and Seyfert galaxies.
COSMIC RAYS AND ACCELERATION MECHANISMS. Observational properties of cosmic rays.Fermi first-order and second order acceleration mechanisms.
INVERSE COMPTON EMISSION.COMPTONIZATION OF RADIATION.Electron scattering.Quantum effects:the Klein-Nishina cross-section. Compton scattering and Inverse Compton.Emitted power from single scattering.Emission by many particles.Effects of multiple IC scatterings (Compton parameter, spectral distortions, Bose-Einstein distributions, thermal and kinetic Sunyaev–Zeldovich effect).X-ray emission of radio-quiet (and radio-loud) AGNs by thermal Comptonization.Compton reflection. AGN Unification Scheme and the X-ray Background. The BLAZAR phenomenon. Inverse Compton production of very high-energy photons: Synchrotron-Self Compton and External Compton emissions. Doppler boosting. Super-luminal motions.
ACCRETION POWER IN ASTROPHYSICS. The compactness parameter. The Eddington limit. Critical accretion regimes. Bondi and spherically-symmetric accretion. The analogue: accretion in binary systems. Plasma viscosity in disks. Thin accretion discs. Observational tests. Accretion in AGNs.
PROPAGATION OF RADIATION THROUGH PLASMAS. Propagation of electromagnetic waves through plasmas. Propagation along magnetic fields: the Faraday rotation. Cherenkov radiation. Electron-Positron Pair Production (in thermal and non-thermal plasmas).
CHERENKOV ASTRONOMY. Detection technique. Atmospheric showers. Imaging the shower. Existing and future facilities. The VHE extragalactic sky.
THE COSMIC PHOTON-PHOTON AND PARTICLE-PHOTON OPACITIES. Extragalactic background radiations, background energy density. The photon opacity, applications to current and future observations.
Planned learning activities and teaching methods: Lecturing and exercizes.
Additional notes about suggested reading: Lecture notes by the teacher, plus textbooks when needed
Textbooks (and optional supplementary readings)
  • Frenk King Raine, Accretion Power in Astrophysics. --: --, --.
  • Longair, High Energy Astrophysics. --: --, --. Cerca nel catalogo
  • Sarazin, X-ray emission from clusters of galaxies. --: Review of Modern Physics 58, 1, --. Cerca nel catalogo
  • M. Vietri, Astrofisica delle Alte Energie. --: Feltrinelli, 2006. Cerca nel catalogo
  • Ribicki & Lightman, Radiative processes in astrophysics. --: Wiley, 2008.