AST1410  Stars  (Fall 2010)

 Course Syllabus

Stellar astrophysics is the best developed subject in all of astrophysics. Multiple physical processes have been brought into an organic synthesis here to successfully explain observations of stars, interstellar material, planets, and galaxies. As such, stellar astrophysics is one of the foundations of modern astrophysics. In addition to discussing the physical and astrophysical aspects of stars, we will also discuss major remaining puzzles in this area.

Instructor: Yanqin Wu, MP 1210, wu@astro

Lectures: Wed. 1:30-3:00PM (AB114), Friday 12:30-2:00PM (AB 114/113)

Office Hour: drop by my office

Course Website:    http://www.astro.utoronto.ca/~wu/AST1410

Textbook: Hansen, Kawaler & Trimble, stellar interiors (2nd edition, 2004, Springer)

Optional Readings:

  1. Piralnik, Stellar Structure and Evolution, 2000, reprinted (clear and concise 2nd-3rd yr undergraduate textbook)

  2. Carroll & Ostlie, An Introduction to Modern Astrophysics (lengthy textbook for 2nd-4th yrs undergraduate courses)

  3. Phillips, The Physics of Stars, 2nd edition ,1994, (3rd-4th yr undergraduate textbook)

  4. Cox & Guili's Principles of Stellar Structure, 2004, (revised version of the old bible)

  5. Collins, Fundamentals of Stellar Astrophysics, 1989 (on-line version)

  6. Clayton, Principles of stellar evolution and nucleosynthesis, 1983

  7. Kippenhahn & Weigert, Stellar structure and evolution, 1990, (another standard textbook)

  8. Rose, Advanced Stellar astrophysics, 1998 (more in-depth discussions of the physics)

  9. Stahler & Palla, the formation of stars, 2004

  10. Mihalas: stellar atmospheres 1970

  11. Schwarzschild, Structure and Evolution of the Stars 1957 (concise, insightful book on stellar physics)

  12. Shu, The Physics of Astrophysics, I/II, 1992 (good basic physics)

  13. Shapiro & Teukolsky, Black Holes, White Dwarfs & Neutron Stars (focus on degenerate objects, also used as high energy astrophysics textbook)

    This graduate course will build upon undergraduate level preparations (as covered by the UofT courses, AST221 stars and planets, AST320 stellar structure, or equivalents). If you have not taken these courses, you will need to make up by reading the above listed undergraduate textbooks. I will assign readings from the other books as we go on. They should be on reserve in the DAA library.


Evaluation:
Problem sets (30%), Oral Presentation (20%), Computer project for stellar evolution (20%), Final exam (20%)

There will be 3 problem sets due two weeks after posting. We will run presentations throughout the term. Each student will present two short (8 min. + 7 min. discussions/questions) and one long (20 min. + 5 min. discussions/questions) talks. The short one will be to explain an important concept in stellar astrophysics, and the long one will be on an advanced topic (list of topics to come). Each student will be required to construct a simple stellar model, and analyse stellar evolution results from the MESA code. The final exam will be a take-home exam of 3 hours duration (no references may be consulted, however).

Course Outline:

Part I    Overview and Requisite physics, 4 wks

1. master equations, equilibria, timescales, mass-radius/mass-luminosity scaling; astronomical backgrounds, Hertzbrung-Russell diagram, common threads in stellar evolution, features in stellar evolution

2. equation of state: fermions and bosons, pressure and energy density, ideal gas, (complete and partial) degenerate gas, radiation pressure, Boltzman distribution, Saha equation;

3. heat loss: radiative diffusion, conduction, opacity sources, Schwarzschild and Ledoux criteria, mixing length theory, convective flux, stellar context for convection, semi-convection;

4. energy production: nuclear binding energy, Coulomb barrier, reaction channels (PP, CNO, He, D/Li burning, s-/r-/p-processes) and rates, neutrinos


Part II. Themes, 8 wks

1. evolution of a sun-like star: Hayashi track, Li burning and Li plateau, solar neutrino problem, pressure ionization and thermal ionization, convection zone advance, rotational evolution, metal pollution by planets, the dim-sun paradox, influences on planets, RG/AGB winds and pollution of the primordial solar nebula, helioseismology

2. brown dwarfs and jovian planets: D/Li burning, gravitational cooling, radiative bottle-neck, semi-convection, dust condensation and opacity (spectra), stellar irradiation and inflated hot jupiters, formation of brown dwarfs and giant planets

3. high mass stars: CNO burning and core convection, Eddington luminosity and formation/mass loss of high mass stars, nucleosynthetic yield of high mass stars, rotational evolution, feedback to the galaxy, core collapse SN (SN II), pair instability, neutrino luminosity, Pop III stars, neutron star (population, rotation, magnetism), gamma-ray burst

4. binary evolution: frequency of binarity, tidal synchronization and circularization, Roche lobe overflow, conservative and non-conservative mass transfer, common envelope, accretion onto degenerate objects (x-ray bursters, novaes, cataclysmic variables), merger of double degenerates, SN Ia (rates, standard candles, neucleosynthetic yield, origin)


Part III. Summary, 1 wk

leading puzzles; peculiar stars