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This is a one-quarter course on stars, stellar evolution, and topics known collectively as ``high energy astrophysics" as it applies to stellar phenomena. Thus the subject matter includes, in addition to the study of the stars themselves (their observed properties and their formation and evolution), such topics as novae, supernovae, nucleosynthesis (the origin of the elements), x-ray sources, pulsars, gamma-ray bursts, neutron stars and black holes. Cosmology and extra-galactic astronomy will be discussed but are not treated in any detail in Ay 12. That subject will be covered, at a similar level, in Ay 13, taught next quarter by Jason Prochaska. Similarly, Ay 18, next quarter, taught by Claire Max, will treat planets and planetary systems. Cosmology and galaxies will also be covered at a less rigorous level in Ay 5 next quarter by Sandra Faber. This quarter, for those interested in the solar system and its exploration, there is Ay 80A, again at an easier level, ``Space Age Astronomy'', taught by Graeme Smith this quarter (12:30, MWF; does not satisfy "Q"). For the broad survey with less mathematics (but satisfies "Q"), consider Ay 2 taught this quarter by Adriane Steinacker (noon, TuThu) and by Raja Guha Thakurta (2 PM MWF). For the highly motivated, probably upper division students among you, there is Ay 113, ``Physical Cosmology", taught by Greg Novack. Finally, Ay 4 taught this quarter in the same time slot as Ay 12 by UCO Director Mike Bolte covers stars and stellar astrophysics with somewhat less math and physics than Ay 12. Ay 4 is intended for non-science majors. Ay 12 is especially intended for science majors and counts toward satisfying requirements for the astrophysics minor. However, it is a self-contained course that should also be accessible to highly motivated non-science majors (see below). Our studies in Astronomy 12 will require knowledge of simple mechanics and some basic ideas about radiation theory, quantum mechanics, and nuclear physics which we shall develop as we go along. The second half of the quarter deals with the evolution of stars, beginning with their formation on the "main sequence", continuing their lives as bright celestial objects, and ending as the star collapses to a white dwarf, neutron star, or black hole. Various phenomena associated with star death (such as supernovae and nucleosynthesis) will be discussed as will implications for Galactic evolution and energetic phenomena associated with collapsed stars. While this course will be taught at a higher level (more math and physics) than the other introductory courses offered this quarter, the material to be presented in Astronomy 12 is self contained. No previous college level math, physics, or astronomy is required, though it certainly would help. It will be assumed however that the student has mastered elementary algebra, including logarithms, simple trigonometry, and fractional powers (as can be done by punching keys on a pocket calculator, e.g., 100.3 = 1.995...), and has some familiarity with basic scientific concepts and reasoning. Elementary calculus will sometimes be used in classroom derivations (though not often) because, for those understanding calculus, it is the easiest and clearest way of obtaining results. It is not expected however that the student will need to use calculus on homework assignments or tests. There will be considerable emphasis on the physical processes believed to be operating in stars and the development of basic physical concepts will form a core part of the course. Thus a background in math (at say the pre-calculus level, Math 3) or physics (5AB or 6AB) will definitely make the course easier. Performance in this course will be judged on the basis of i) an in class, graded mid-term exam (roughly 25%); ii) a similar final exam (roughly 30%); iii) 4 graded homework sets (roughly 35%) and in class participation (up to 10%). Questions and class-room discussion are encouraged, both for your benefit and to aid me in properly pacing the course. You have the option of a letter grade (with evaluation) if you wish. This course also counts toward the astrophysics minor. The recommended text (but not required) for this course is Voyages to the Stars and Galaxies: THird Edition by Fraknoi, Morrison, and Wolff (FMW). It is modern, but far too superficial mathematically for my liking. It does give many interesting links on the web for further study. Somewhat harder and too mathematical to be our main textbook is Introductory Astronomy and Astrophysics, fourth edition by Zeilik and Gregory. Despite its opacity, some of the physics discussions and equations presented there will be useful in this course. Specific readings in our recommended text Fraknoi, Morrison, and Wolff, will be suggested below. Both books will be on reserve at the Science Library. Increasingly, large amounts of useful information are available on the internet. We will maintain a current website for the course at There you will find copies of the transparencies used in class, homework assignments, course syllabus, constant sheet, and reviews for the mid-term and final, and many other interesting links. Unless there are problems with access - an issue to be explored in class - some exercises and homework may involve using the web. A good starting point with lots of links is I strongly urge those of you with web access (everybody?) to follow the topics of our class at these sites. Because not all the material to be presented in this course is contained in any one book, your attendance is strongly encouraged. Taking accurate detailed notes is also strongly advised as you will need them in order to do the homework and the open notes portions of the two exams. If web access poses a problem for anyone, We will endeavor to keep an up to date copy of the class notes on reserve in the Science Library, but you will find these hard to follow if you don't come to class. Class will meet twice weekly (TuTh 2 PM) in the Physical and Biological Sciences (PBS) Building, Room 136. There will be a graduate Teaching Assistant, Jess Johnson. His office is in Natural Sciences II, room 187 and his phone number is 9-1637. Students can stop by his office by making an appointment, but he will definitely be in his office during official Office Hours: Tuesday 11 AM - 2 PM. Info on discussion sections will be given in class. Section will be held weekly at 3:30 PM on Wednesday in Interdisciplinary Sciences Room 356. I will also be available during office hours (3:45 - 5:30 PM Th, IDS 259) or at other times by appointment, though Jess should be the one you first turn to with questions regarding course material. It will be advisable to purchase a small inexpensive calculator, if you do not already own one. Be sure to get one that does powers, roots, trig, and logarithms. A general outline of topics and relevant page numbers in the text follows. The actual material covered will vary somewhat and the topics near the end will depend on our rate of progress. Roman numerals do not correspond to the lecture number, but do indicate the approximate sequencing of topics. The references are based on the 2nd edition of Voyage to the Stars and Galaxies (FMW) and Nick Strobel's hypertextbook (NS). You may also want to begin by looking at NS ``Appendix B: A Mathematical Review''. I. INTRODUCTION The scope of the Universe and the place of the stars in the grand scheme of things. Overview of course material. FMW Prologue; Chapter 1, 9.1; NS ``Astronomy as a Science and a Sense of Scale''. II. DESCRIPTIVE ASTRONOMY The location of the sun in the sky. Right ascension, declination, longitude, and latitude. The celestial sphere and coordinates. FMW 1, 3; NS ``Astronomy Without a Telescope'' III. GENERAL ASTROPHYSICAL CONCEPTS 1. Newtonian physics, fundamental forces, gravitation. 2. Kepler's Laws 3. Energy: kinetic, gravitational, electrical, thermal, nuclear. 4. Weighing the galaxy. Evidence for dark matter. FMW 2, 16; NS ``Newton's Law of Gravity'' IV. STELLAR DISTANCE DETERMINATIONS 1. Luminosity, flux, magnitude definitions 2. Parallax's and proper motions; distance determinations 3. Cepheid variables; P-L relations; distances to local groups 4. Other standard candles - brightest stars, H II regions, supernovae 5. The Tully-Fisher relation. 6. Hubble's law FMW 10; NS ``Stellar Properties'' (first half) and last part of ``Other Galaxies and Active Galaxies'' - Steps to the Hubble Constant V. RADIATION 1. General properties 2. Transparency of Earth's atmosphere 3. Black body radiation and the greenhouse effect 4. Stellar temperatures 5. Quantum physics - the Bohr atom 6. Emission and absorption of radiation 7. Doppler shift 8. Stellar spectra FMW 4, 5; NS ``Electromagnetic Radiation'' VI. OBSERVATIONALLY DETERMINED PROPERTIES OF STARS 1. Determination of stellar radii, surface temperatures, mass, composition, etc. 2. Hertzsprung-Russell diagram 3. Star clusters; distances, ages 4. Stellar populations; history of the Galaxy. FMW 8, 9; NS ``Stellar Properties'' (second half) VII. THE INTERSTELLAR MEDIUM AND STAR FORMATION 1. The viral theorem 2. The Jean's mass 3. The interstellar medium and molecular clouds 4. Observational evidence for star formation FMW 11, 12; NS ``The Interstellar Medium'' and the first part of ``Lives and Deaths of Stars'' VIII. STELLAR INTERIORS AND STELLAR EVOLUTION 1. Concepts of pressure and equation of state 2. Kinds of pressure 3. Hydrostatic equilibrium 4. The sun, a typical star 5. Degeneracy pressure and the minimum mass of a star 6. Nuclear physics 7. Hydrogen burning and the main sequence of the HR diagram 8. The solar neutrino ``problem'' FMW 6, 7; NS ``Our Sun and Stellar Structure'' IX. LATE EVOLUTION OF THE SUN AND OTHER LOW MASS STARS 1. Helium burning in stars 2. Red giant stars 3. The s-process: making tin and lead from iron 4. Planetary nebulae 5. Formation and properties of white dwarf stars FMW 13; NS ``Lives and Deaths of Stars'' (middle part) X. THE FINAL EVOLUTION OF MASSIVE STARS 1. Advanced stages of nuclear burning. The role of neutrinos 2. Observed properties of supernovae 3. The gravity bomb: How supernovae of Types II and Ib work 4. Supernova 1987A 5. Nucleosynthesis of elements up to nickel 6. The r-process: Making gold and platinum from iron. 5. Supernova remnants FMW 14; NS ``Lives and Deaths of Stars'' (last part) XI. MASS EXCHANGING BINARY SYSTEMS 1. Mass exchange in binary star evolution 2. Novae 3. Type 1a supernovae FMW 14 XII. COLLAPSED STARS AND THEIR OUTBURSTS 1. Properties of neutron stars and black holes 2. Accreting x-ray sources 3. Pulsars FMW 14, 15 XIII. GAMMA-RAY BURSTS, HYPERNOVAE, AND BLACK HOLE BIRTH FMW 15, 18-interlude |