Program Overview

Physics of the Stars Program

Overview

The Physics of the Stars program is designed to provide students with a comprehensive understanding of the theory of stellar atmospheres, fundamental processes of radiative transfer in stellar atmospheres, and the formation of continuous and line spectra.

Course Goals

The principal aim of the course is to give students an introduction into the theory of stellar atmospheres and the formation of stellar spectra. Students will master basic tools for the analysis and diagnostics of stellar spectra as a key for understanding the physical processes in stellar atmospheres and interiors of stars.

Learning Outcomes

By the end of the course, students will be able to:

• Describe fundamental properties of stars
• Understand the role of stellar mass and radius with a set of differential equations of the stellar structure
• Qualitatively and quantitatively describe radiative transfer in stellar atmospheres
• Apply Schuster-Schwarzschild and Eddington approximations in the solution of the radiative transfer equation in stellar atmospheres
• Apply Chandrashekhar's exact method in solving the radiative transfer equation
• Describe the setup of stellar atmosphere models and apply them in the calculation of stellar spectra
• Understand line absorption and line broadening mechanisms
• Use computer software for the spectroscopic diagnostics of stellar atmospheres
• Understand differences between stellar chromospheres and coronae and describe their properties
• Understand the formation and properties of stellar winds and stellar oscillations

Course Description

The course covers the following topics:

1. Fundamental stellar properties and data
2. Fundamental radiative quantities
3. The equation of radiative transfer in stellar atmospheres
4. Source function
5. Schuster-Schwarzschild approximation
6. Eddington approximation
7. Chandrasekhar's exact method
8. Opacity of stellar matter; Boltzmann and Saha equations
9. Models of stellar atmospheres
10. Line absorption
11. Line broadening mechanisms
12. Spectroscopic diagnostics of stellar atmospheres
13. Hydrogen lines
14. Stellar chromospheres and coronae; stellar winds
15. Stellar oscillations (asteroseismology)

Requirements for Students

Regular lecture attendance, active participation in tutorials, oral presentation of a seminar, and a report including computer programming are required.

Grading and Assessing the Work of Students

The final grade is a combination of grades obtained from:

• Written exam (60%)
• Seminar (20%)
• Computer program (20%)

Literature

1. E. Bohm-Vitense, Introduction to Stellar Astrophysics, vol. 2, Cambridge University Press, Cambridge, 1989
2. W. Novotny, Introduction to Stellar Atmospheres and Interiors, Oxford University Press, New York, 1973

Prerequisites

Attendance of Introduction to Astrophysics is required for enrollment.

Semester Information

This course is available in the 7th and 8th semesters of the regular study program in Physics.