PLASMA SPECTROSCOPY

Academic Year 2020/2021 - 1° Year - Curriculum ASTROPHYSICS
Teaching Staff: Francesco LEONE
Credit Value: 6
Scientific field: FIS/03 - Physics of matter
Taught classes: 42 hours
Term / Semester:

Learning Objectives

Processes of Atomic Physics and arguments on the Interaction between Mater and Radiation are here combined to supply a description of plasma properties on the basis of high resolution spectroscopy. Laboratory plasmas and astrophysical environments will be discussed in more detail. Applications and numerical solutions of Plasma Spectroscopy will be presented in the course Laboratory Astrophysics II.

The aim of the course is to contribute to: Convert the theoretical knowledge into applications and tools aimed at measuring physical parameters. Consolidate the understanding of the interconnections between theoretical and experimental / observational aspects, even in interdisciplinary areas. The development of critical skills in the analysis and interpretation of both observational and experimental scientific results. Boost, by means of the design and implementation of tools and software, the analytical capacity understood as a subdivision of a complex process into fundamental parts and in the identification of their mutual influences and consequentiality. Develop the ability to evaluate results by comparing them with what is reported in the literature. Develop the language necessary for communicating the topics covered by this course. Strengthen the ability to report on the activities carried out both orally and in writing.


Course Structure

Lectures.

Note: should the circumstances require online or blended teaching, appropriate modifications to what is hereby stated may be introduced, in order to achieve the main objectives of the course.


Detailed Course Content

Reminding, nomenclature and conventions: Spectrum of the Radiation. Polarisation. Properties of Stokes parameters. Quantisation of the Electromagnetic Field. The Dirac Equation for a Free Particle. Schrödinger Equation. Method of matrix . Radiative processes in plasma.

Spettroscopia Atomica: Hydrogen spectrum. Alkaline Spettrum. Spettrum of atoms with many valence electrons. Term Energy.

Laws of Thermodynamic Equilibrium​: I principi della statistica. La distribuzione Maxwelliana delle velocità. La legge di Saha-Boltzmann.

Interaction Between Matter and Radiation: The Interaction Hamiltonian. The Statistical Equilibrium Equations. Einstein coefficients. The Radiative Transfer Equation. TheAbsorptionandEmissionCoefficients. Selction rules. Transizioni proibite e semi-proibite. Intensità delle righe spettrali.

Non-equilibrium Plasmas: Kinetic temperature of electrons. Collisional Processesi. Dielectronic Recombination and auto-ionisation. Charge exchange.

Radiative Transfer​: Formal Solution. Continuum emission and Spectral lines in thermodinamic equilibrium. Spectral lines in non-equilibrium condition. Polarisation of atomic levels. Polarised Radiative transfer. Polarisation across spectral linesi.

Astrophysical Plasmas: Stellar Atmospheres: radiative-equilibrium models in Local Thermodinamic Equilibrium. Solution of the radiative transfer equation. Stellar Spectra. Forbidden lines in astrophsyical environments.

Laboratory Plasma Diagnostic: Density and temperature of eòectronic and ionic components


Textbook Information

Gray D.F., The observation and analysis of stellar spectra – Cambridge Astrophysics Series

Kunze, H-J., Introduction to Plasma Spectroscopy - Springer Series

Landi Degl'Innocenti E. - Atomic Spectroscopy and Radiative Process - Springer Series

Landi Degl'Innocenti E., Landolfi M. - Polarization in Spectral Lines - Kluwer Academic Publishers

Mihalas D., - Stellar Atmospheres. - San Francisco: W. H. Freeman & Company