Astronomy 321: Stellar Structure and Evolution

318 Willamette Hall

14:00-15:50

Astronomy 321: Stellar Structure and Evolution is an intermediate course on the structure, and evolution of stars. Stellar strucure is a mature field whose observational foundations and basic throry were formed in the early 1900s and mid-1900s, resepctively. In this course, (1) we review observations which led to determination of the fundamental properties of the stars, the tying together of the stellar properties in the Hertzsprung-Russell diagram and the basic theoretical statment of the Ruseell-Vogt Theorem. (2) We then present and derive the fundatmental equations of stellar strucutre, essentailly mass, momentum, and enery conservation, next going over the fundamental constituive relations for stellar material such as the equation of state, and opacity, and the physical processes important to stellar structure such as nuclear fusion. After developing the fundamental equations of stellar structure (3) we consider the evolution of stars from their bith in interstellar medium clouds to the lives as normal stars on the Main Sequence, the sub-Giant and Giant Branch, and the Horizontal Branch and Asymptoitc Giant Branch. (4) we then look at the final phases of their evolution through the formation of planetary nebulae to white dwarfs or through Type II supernovae to neutron stars or black holes. (5) Stellar structure is a meeting place between observational astronomy, numerical modeling, and physics on small scales and general relativity. In this vein, we discuss the Solar Neutrino Problem, Type Ia supernovae, the observed ages of stars, black hole binary systems, and Gamma-ray bursters.

Prerequisites, Physics 253, and Math 253. Suggested Corequisites: Physics 351, and Math 256 or familiarity with one-dimensional ordinary differential equations.

Instructor: Jim Imamura
Office: 457 Willamette Hall
Office Hours: Tu/Th 10:00-12:00 or by appointment
E-mail: imamura@uoregon.edu
Phone: 541-346-5212

Course: Astr 321: Stellar Structure and Evolution
Course CRN: 26043
Text: An Introduction to Modern Astrophysics, 2nd edition, Carroll & Ostlie
Class: 14:00-15:50, MW
Room: 318 Willamette Hall

Grading:
Test Dates or

Week

Material

Notes

1,2

Chapters 2.1,2.3, 3, 5.1,5.3,5.4, 7, and 8: Why Do We Study Stars? How Do We Study Stars? Properties of Stars: Spectral Analysis; Lines and MK Spectral Classification; Tying Things Together: Hertzsprung-Russell (HR) Diagram, Mass-Luminosity Relation, Mass-Radius Relation, Luminosity Function, ...

Notes

3

Chapter 10: Interiors of Stars. We consider the basic equations of stellar structure: mass conservation, momentum conservation (hydrostatic equilibrium), and energy conservation.

Notes

4

Chapter 10: Interiors of Stars. We continue with the microphysics needed for the modeling of stars such as formulations for the pressure, stellar energy sources (thermal energy, gravitational contraction, nuclear energy), nuclear reactions, quantum mechanical tunneling, and energy transport (radiation transport, convection, and conduction). Chapter 11: The Sun. The detailed properties of the Sun are considered, the active versus quiet Sun, and tests of the structure of the Sun, Solar Neutrino Problem and Solar Oscillations.

Notes

5,6

Chapter 10: Main Sequence, general properties of Main Sequence stars, masses, luminosities, radii, surface temperatures; scaling laws and homology; lower mass limit to Main Sequence, Heisenberg Uncertainty Principle, Pauli Exclusion Principle, degeneracy pressure (nonrelativisitc and relativistic); upper limit to main sequence stars, radiation pressure, Eddington limit, energy equation and virial theorem; numerical solution of stellar structure equations.

Notes

7,8

Chapter 13: Main Sequence and Post-Main Sequence Stellar Evolution. Rusell-Vogt theorem; high mass versus low mass stars; stellar nucleosynthesis; endpoints of stellar evolution. We follow the post-Main Sequence evolution of the Sun through the ascent of the Asymptotic Giant Branch (AGB), through the Planetary Stage, and into the White Dwarf stage (Chapter 16). We pay particular attention to thermal pulsing, stellar nucleosynthesis, and white dwarf cooling.

...

9

Chapter 13: Main Sequence and Post-Main Sequence Stellar Evolution. (Continued) We follow the post-Main Sequence evolution of the Sun through the ascent of the Asymptotic Giant Branch (AGB), through the Planetary Stage, and into the White Dwarf stage (Chapter 16). We pay particular attention to thermal pulsing, stellar nucleosynthesis, and white dwarf cooling. We consider Type Ia SN paying particular attention to nucleosynthesis and the standardizable nature of Type Ia SN and the expansion of the Universe.

Notes

9,10

Chapter 13: Main Sequence and Post-Main Sequence Stellar Evolution. We follow the post-Main Sequence evolution of massive stars through Type II SN (Chapter 15) into the neutron star stage (second half of Chapter 16) with particular attention paid to SN 1987a, the last historical supernova and its implications for progenitor stars of Type II SN, the core-collapse scenario (in particular through neutrinos).

Notes

10

Chapter 17: General Relativity and Black Holes. Brief introduction to special and general relativty with particular emphasis on aspects relevant to stellar structure and evolution; space-time, the metric, how space and time are coupled, Scnotesarzschild and Kerr black holes, Schwarschild radius, event horizon, singularity. Particular emphases is directed toward the recent discovery of gravitational wave radiation from merging black hole systems by the Laser Interferometer Gravitational-wave Observatory (LIGO) and the study of the binary pulsar

Notes

University Policy Guidelines

Accessible Education

Please let me know within the first two weeks of the term if you need assistance to fully participate in the course. Participation includes access to lectures, web-based information, in-class activities, and exams. The Accessible Education Center (http://aec.uoregon.edu/) works with students to provide an instructor notification letter that outlines accommodations and adjustments to class design that will enable better access. You are encouraged to contact the Accessible Education Center in 360 Oregon Hall at 541-346-1155 or uoaec@uoregon.edu for assistance with access or disability-related questions or concerns. Attendance when Ill or Symptomatic

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University Health Services help students cope with difficult emotions and life stressors. If you need general resources on coping with stress or want to talk with another student who has been in the same place as you, visit the Duck Nest (located in the EMU on the ground floor) and get help from one of the specially trained Peer Wellness Advocates. Find out more at health.uoregon.edu/ducknest.

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Students who participate in university-sponsored activities that might cause them to miss class are responsible for providing documentation signed by a university employee verifying their participation in the activity and listing the dates that they might miss class. This should be done during week one of the term.