Astrophysics

Ay 1. The Evolving Universe. 9 units (3-3-3); third term. This course is intended primarily for freshmen not expecting to take more advanced astronomy courses and will satisfy the menu requirement of the Caltech core curriculum. Introduction to modern astronomy that will illustrate the accomplishments, techniques, and scientific methodology of contemporary astronomy. The course will be organized around a set of basic questions, showing how our answers have changed in response to fresh observational discoveries. Topics to be discussed will include telescopes, stars, planets, the search for life elsewhere in the universe, supernovae, pulsars, black holes, galaxies and their active nuclei, and the Big Bang. There will be a series of laboratory exercises intended to highlight the path from data acquisition to scientific interpretation. Students will also be required to produce a term paper on an astronomical topic of their choice and make a short oral presentation. In addition, a field trip to Palomar Observatory will be organized. Not offered on a pass/fail basis. Instructor: Steidel.

Ge/Ay 11 c. Planetary Sciences. 9 units (3-0-6). For course description, see Geological and Planetary Sciences.

Ay 20. Basic Astronomy and the Galaxy. 9 units (3-0-6); first term. Prerequisites: Ma 1 abc, Ph 1 abc, or for freshmen with a strong high-school background in math and physics. Astronomical terminology. Stellar masses, distances, and motions. Star clusters and their galactic distributions. Stellar spectra, magnitudes, and colors. Structure and dynamics of the galaxy. Instructor: Blain.

Ay 21. Galaxies and Cosmology. 9 units (3-0-6); second term. Cosmological models and parameters, extragalactic distance scale, cosmological tests; constituents of the universe, dark matter, and dark energy; thermal history of the universe, cosmic nucleosynthesis, recombination, and cosmic microwave background; formation and evolution of structure in the universe; galaxy clusters, large-scale structure and its evolution; galaxies, their properties and fundamental correlations; formation and evolution of galaxies, deep surveys; star formation history of the universe; quasars and other active galactic nuclei, and their evolution; structure and evolution of the intergalactic medium; diffuse extragalactic backgrounds; the first stars, galaxies, and the reionization era. Instructor: Djorgovski.

Ay 30. Current Trends in Astronomy. 3 units (2-0-1); second term. Weekly seminar open to declared Ay majors at the discretion of the instructor; nonmajors who have taken astronomy courses may be admitted. This seminar is held in faculty homes in the evening and is designed to encourage student communication skills as they are introduced to faculty members and their research. Graded pass/fail. Instructor: W. Sargent.

Ay 31. Writing in Astronomy. 3 units; third term. This course is intended to provide practical experience in the types of writing expected of professional astronomers. Example styles include research proposals, topical reviews, professional journal manuscripts, and articles for popular magazines such as Astronomy or Sky and Telescope. Each student will adopt one of these formats in consultation with the course instructor and write an original piece. An outline and several drafts reviewed by both a faculty mentor familiar with the topic and the course instructor are required. This course is open only to those who have taken upper-level astronomy courses. Fulfills the Institute scientific writing requirement. Instructor: Hillenbrand.

Ay 40. Inventing Reality: The Human Search for Truth. 9 units (3-0-6); third term. In this course, students will trace the history of cosmological thought by reading directly from the original writings of such thinkers as Aristotle, Newton, Einstein, and Hubble, en route to an understanding of how current observations are being used to determine the origin, evolution, and fate of the universe. While the primary focus will be cosmology, related topics in classical physics, quantum mechanics, and philosophy will also be considered. Not offered 2006–07.

Ay 43. Reading in Astronomy and Astrophysics. Units in accordance with work accomplished. Student must have a definite reading plan and obtain instructor’s permission before registering. Graded pass/fail.

Ay 78 abc. Senior Thesis. 9 units. Prerequisite: To register for this course, the student must obtain approval of the astronomy option representative and the prospective thesis adviser. Open only to senior astronomy majors. This research must be supervised by a faculty member, student’s thesis adviser. The written thesis must be completed and approved by the adviser before the end of the third term. Students wishing assistance in finding an adviser and/or a topic for a senior thesis are invited to consult with the astronomy option representative. A grade will not be assigned in Ay 78 until the end of the third term. P grades will be given the first two terms, and then changed at the end of the course to the appropriate letter grade.

Ay 101. Physics of Stars. 11 units (3-2-6); first term. Prerequisite: Ay 20. Physics of stellar atmospheres. Properties of stars, stellar spectra, radiative transfer, line formation. Stellar structure, stellar evolution, evolution of binaries. Nucleosynthesis in stars. Stellar oscillations. Instructor: Hillenbrand.

Ay 102. Physics of the Interstellar Medium. 9 units (3-0-6); second term. Prerequisite: Ay 20. An introduction to observations of the interstellar medium and relevant physical processes. The structure and hydrodynamic evolution of ionized hydrogen regions associated with massive stars and supernovae, thermal balance in neutral and ionized phases, star formation and global models for the interstellar medium. Instructors: A. Sargent, Scoville.

Ay 105. Optical Astronomy Instrumentation Lab. 9 units (1-6-2); third term. Prerequisite: Ay 20. An opportunity for astronomy and physics undergraduates (juniors and seniors) to gain firsthand experience with the basic instrumentation tools of modern optical and infrared astronomy. The 10 weekly lab experiments are expected to include radiometry measurements, geometrical optics, optical aberrations and ray tracing, spectroscopy, fiber optics, CCD electronics, CCD characterization, photon counting detectors, vacuum and cryogenic technology, and stepper motors and encoders. Instructors: Blain, Steidel.

Ay 121. Radiative Processes. 9 units (3-0-6); first term. Prerequisites: Ay 101 (undergraduates); Ph 125 or equivalent. The interaction of radiation with matter: radiative transfer, emission, and absorption. Compton processes, synchrotron radiation, collisional excitation, spectroscopy of atoms and molecules. Instructor: Readhead.

Ay 122. Astronomical Measurements and Instrumentation. 9 units (3-0-6); first term. Prerequisite: Ph 106 or equivalent. Measurement and signal analysis techniques throughout the electromagnetic spectrum. Telescopes and interferometers; detectors and receivers; photometry and radiometry; imaging devices and image processing; spectrometers; space telescopes. Instructors: Djorgovski, Readhead.

Ay 123. Structure and Evolution of Stars. 9 units (3-0-6); first term. Prerequisites: Ay 101 (undergraduates); Ph 125 or equivalent. Thermo-dynamics, equation of state, convection, opacity, radiative transfer, stellar atmospheres, nuclear reactions, and stellar models. Evolution of low- and high-mass stars, supernovae, and binary stars. Instructors: Cohen, Sari.

Ay 124. Structure and Dynamics of Galaxies. 9 units (3-0-6); second term. Prerequisites: Ay 21 (undergraduates); Ph 106 or equivalent. Stellar dynamics and properties of galaxies; kinematics and dynamics of our galaxy; spiral structure; stellar composition, masses, and rotation of external galaxies; star clusters; galactic evolution; binaries, groups, and clusters of galaxies. Instructor: W. Sargent.

Ay 125. High-Energy Astrophysics. 9 units (3-0-6); third term. Prerequisites: Ay 21 (undergraduates); Ph 106 or equivalent. High-energy astrophysics and the final stages of stellar evolution; supernovae, binary stars, accretion disks, pulsars; extragalactic radio sources; active galactic nuclei; black holes. Instructor: Kulkarni.

Ay 126. Interstellar Medium. 9 units (3-0-6); second term. Prerequisite: Ay 102 (undergraduates). Physical processes in the interstellar medium. Ionization, thermal and dynamic balance of interstellar medium, molecular clouds, hydrodynamics, magnetic fields, H II regions, supernova remnants, star formation, global structure of interstellar medium. Instructors: A. Sargent, Scoville.

Ay 127. Cosmology and Galaxy Formation. 9 units (3-0-6); third term. Prerequisites: Ay 21 (undergraduates); Ph 106 or equivalent. Cosmology; extragalactic distance determinations; relativistic cosmological models; galaxy formation and clustering; thermal history of the universe, microwave background; nucleosynthesis; cosmological tests. Instructor: Phinney.

Ge/Ay 132. Atomic and Molecular Processes in Astronomy and Planetary Sciences. 9 units (3-0-6). For course description, see Geological and Planetary Sciences.

Ge/Ay 133. The Formation and Evolution of Planetary Systems. 9 units (3-0-6). For course description, see Geological and Planetary Sciences.

Ge/Ay 137. Planetary Physics. 9 units (3-0-6). For course description, see Geological and Planetary Sciences.

Ay 141 abc. Research Conference in Astronomy. 3 units (1-0-2); first, second, third terms. Oral reports by astronomy students on current research. These provide an opportunity for practice in the organization and presentation of reports. A minimum of two presentations will be expected from each student each year. This course fulfills the option oral communication requirement and is required of all astronomy graduate students who have passed their preliminary exams. It is also recommended for astronomy seniors. Graded pass/fail. Instructors: Kulkarni, Sari, Hillenbrand, Kamionkowski, A. Sargent, Djorgovski.

Ay 142. Research in Astronomy and Astrophysics. Units in accordance with work accomplished. The student should consult a member of the department and have a definite program of research outlined. Approval by the student’s adviser must be obtained before registering. 36 units of Ay 142 or Ay 143 required for candidacy. Graded pass/fail.

Ay 143. Reading and Independent Study. Units in accordance with work accomplished. The student should consult a member of the department and have a definite program of reading and independent study outlined. Approval by the student’s adviser must be obtained before registering. 36 units of Ay 142 or Ay 143 required for candidacy. Graded pass/fail.

Ay 211. Extragalactic Astronomy. 9 units (3-0-6); third term. Prerequisites: Ay 123, Ay 124, and Ay 127. This is an advanced course in extragalactic astronomy and aims to cover the following topics: cosmological background, origin of the galactic halo, stellar nucleosynthesis, primordial element abundances, QSO absorption lines, nature of the Ly alpha forest, physics and evolution of AGNs, gravitational lensing and dark matter, origin of elliptical galaxies, environmental processes in galaxy evolution, supernovae as cosmological probes, searches for high redshift galaxies, the galaxy luminosity function, assembly history of the Milky Way and M31. Not offered 2006–07.

Ay 215. Seminar in Theoretical Astrophysics. 9 units (3-0-6); third term. Course for graduate students and seniors in astronomy and planetary science. Students will be required to lead some discussions. Topic will be selected based on student interest. Not offered 2006–07.