Course plan:

• Stellar structure and evolution
• Radiative processes
• Stellar photospheres
• Interstellar Medium
• etc…

Theoretical and practical considerations will be supplemented with the home exercises which constitute the important part of the course.

Literature:

Textbook choice for this course is largely a matter of personal taste. I provide below a list of recommended books. Study them in parallel with the lectures.

• Stellar Structure and Evolution – Onno Pols, Utrecht, 2014 (Free)
• An Introduction to the Theory of Stellar Structure and Evolution – Dina Prialnik
• Introduction to Stellar Astrophysics: Vol 2 – E. Böhm-Vitense
• Introduction to Stellar Astrophysics: Vol 3 – E. Böhm-Vitense
• Observations and analysis of stellar photospheres – D. F. Gray [E-Book]
• Lecture notes (Part I) – not enough!

Compulsory problems (return by the deadline). 5+ sets (30% of the final score).

• deadline 28.01.2026 [set 1] * Solutions
• deadline 11.02.2026 [set 2] * Solutions

Schedule

• Lecture 1: January 7: Introduction (What is Astrophysics and Theoretical Astrophysics? Astronomical units). Stars (Role of stars; Definition; What can we learn from observations?).
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• January 8: NO CLASS
• Lecture 2: January 14: Stars (Properties of stars; Stellar timeline; basic assumptions, mass conservation, hydrostatic equilibrium).
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• Lecture 3: January 19: Stars (Virial theorem. Timescales of stellar evolution. Conditions in stellar interiors).
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• Lecture 4: January 21: Stars (Energy generation. The equation of conservation of energy). Basics about radiative transfer (Specific intensity. Absorption coefficient).
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• Lecture 5: January 22: Basics about radiative transfer (Radiation terms, specific intensity, interaction radiation – matter, parallel-ray radiative transfer equation, solution of the parallel-ray RTE)
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  Compulsory problems: Set 1 (return by January 28).
• Lecture 6: January 26: Basics about radiative transfer (Mean Intensity, Flux, and K-integral. RTE in plane-parallel atmosphere. The temperature gradient for radiative transport). The equations of stellar structure and possible ways to solve them. Boundary conditions.
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• Lecture 7: January 28: Convection and conditions for its occurrence. Equation of state (EOS). Degeneracy pressure.
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• Exercise session: January 29. Solution of HW1.
• Lecture 8: February 2: The equations of stellar structure (stellar opacity). Nuclear Energy Production (Basics on nuclear reactions, the binding energy, Quantum tunnelling, Reaction cross-section).
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• Lecture 9: February 4: Nuclear Energy Production (The Gamow peak, Nuclear Reaction Rates, Electron shielding). Nuclear reactions in stellar interiors (Energy generation, PP-chains & CNO-cycle, Helium burning, Carbon burning and beyond)
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  Compulsory problems: Set 2 (return by February 11).
• February 5: NO CLASS
• Lecture 10: February 9: Nuclear reactions in stellar interiors (iron and heavier elements, Composition changes). Solution of the Equations of Stellar Structure (The stellar structure equations and how to solve them? Simple stellar models. Polytropic models. Lane-Emden equation. Different relationships for polytropic stars.).
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• Exercise session: February 11. Solution of HW2.
• Lecture 11: February 12: Solution of the Equations of Stellar Structure (Different relationships for polytropic stars. Chandrasekhar mass. Dynamical stability of stars). Stellar evolution codes. Schematic stellar evolution.
  PDF * EZ-Web
• Lecture 12: February 16: Star formation. Identification of Young Stars.
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• Lecture 13: February 18: Pre-main sequence star evolution (the Hayashi track and the Henyey track). Main Sequence stars.
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• Lecture 14: February 19: Evolution of low-mass stars. Evolution of high-mass stars. The initial mass function.
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• Lecture 15: February 23: The end point: stellar remnants. White dwarfs, Supernovae, Neutron stars, Black holes.
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• February 25:
  

  Mid-term exam