Astrophysics (Ay) Graduate Courses (2024-25)
Ay 101.
Physics of Stars.
9 units (3-0-6):
first term.
Prerequisites: Ay 20 is recommended.
Physics of stellar interiors and stellar atmospheres. Stellar structure including nucleosynthesis in the cores of stars and energy transport. Stellar evolution. Fundamental properties of stars. The H-R diagram. Stellar spectra, radiative transfer, and spectral line formation. Additional topics may include: stellar oscillations, rotation, mass loss, binary evolution.
Instructor: Fuller.
Ay 102.
Physics of the Interstellar Medium.
9 units (3-0-6):
second term.
Prerequisites: Ay 20 is recommended.
An introduction to observations of the interstellar medium and relevant physical processes. Phases of the gaseous interstellar medium. Thermal balance in neutral and ionized gas. Molecular gas and star formation. Structure and hydrodynamic evolution of ionized regions associated with massive stars; supernovae. Global models for the interstellar medium. Interstellar and circumstellar dust.
Instructor: Phinney.
Ay/Ph 104.
Relativistic Astrophysics.
9 units (3-0-6):
third term.
Prerequisites: Ph 1, Ph 2 ab.
This course is designed primarily for junior and senior undergraduates in astrophysics and physics. It covers the physics of black holes and neutron stars, including accretion, particle acceleration and gravitational waves, as well as their observable consequences: (neutron stars) pulsars, magnetars, X-ray binaries, gamma-ray bursts; (black holes) X-ray transients, tidal disruption and quasars/active galaxies and sources of gravitational waves.
Not offered 2024-25.
Ay 105.
Optical Astronomy Instrumentation Lab.
9 units (1-5-3):
third term.
Prerequisites: 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 include radiometry measurements, geometrical optics, polarization, optical aberrations, spectroscopy, CCD characterization, vacuum and cryogenic technology, infrared detector technology, adaptive optics (wavefront sensors, deformable mirrors, closed loop control) and a coronography tutorial.
Instructor: Hallinan.
Ay/Ge 107.
Introduction to Astronomical Observation.
12 units (2-2-8):
third term.
Prerequisites: CS 1 or equivalent coding experience recommended.
This hands-on, project-based course covers the design, proposal, and execution of astronomical observations, the basics of data reduction and analysis, and interacting with astronomical survey catalogs. The scope of the course includes imaging and spectroscopic observational techniques at optical and infrared wavelengths. The format centers on projects and practical skills but also includes a lecture and problem set component to establish the theoretical underpinnings of the practical work. Specific course components include: (a) Students will learn to use small, portable telescopes and find and image objects of interest using finder charts; (b) Students will build basic data reduction pipelines for imaging and spectroscopy data to understand how these types of data are used to derive scientific results; (c) Students will use Palomar Observatory to propose and execute their own research projects focused on astrophysical or planetary topics; (d) Students will query and work with data from on-line archives and catalogs. The class meets twice a week during the daytime plus one weekly evening telescope session, and has a required field trip to Palomar Observatory. Students interested in enrolling should review the logistical information on this page and ensure their schedule allows attendance of all course components prior to registering: https://dekleer.caltech.edu/ayge107. Enrollment is limited.
Instructors: Hillenbrand, de Kleer.
Ay 111 abc.
Introduction to Current Astrophysics Research.
1 unit (1-0-0):
first, second terms.
This course is intended primarily for first-year Ay graduate students, although participation is open and encouraged. Students are required to attend seminar-style lectures given by astrophysics faculty members and other researchers. The intent of the course is for students to gain an understanding of the breadth of astrophysics research that is conducted at Caltech, and to learn about potential research opportunities, as well as different career paths in astronomy. Credit is also given for attending the weekly astronomy colloquia. At the end of each term, students are required to summarize in oral or written form (at the discretion of the instructor), one of the covered subjects that drew their interest.
Part c not offered 2024-25.
Instructors: El-Badry, Djorgovksi.
Ge/Ay 117.
Bayesian Statistics and Data Analysis.
9 units (3-0-6):
second term.
Prerequisites: CS 1 or equivalent.
In modern fields of planetary science and astronomy, vast quantities of data are often available to researchers. The challenge is converting this information into meaningful knowledge about the universe. The primary focus of this course is the development of a broad and general tool set that can be applied to the student's own research. We will use case studies from the astrophysical and planetary science literature as our guide as we learn about common pitfalls, explore strategies for data analysis, understand how to select the best model for the task at hand, and learn the importance of properly quantifying and reporting the level of confidence in one's conclusions.
Instructor: Knutson.
Ay 119.
Astroinformatics.
6 units (3-0-3):
third term.
This class is an introduction to the data science skills from the applied computer science, statistics, and information technology, that are needed for a modern research in any data-intensive field, but with a special focus on the astronomical applications. Open to graduate and upper-division on undergraduate students in all options. The topics covered include best programming practices, supervised and unsupervised machine learning, feature selection, dimensionality reduction, databases, Bayesian statistics, time series analysis, deep learning, data visualization, and possibly other topics. The class will feature real-world examples from cutting-edge projects in which the instructors are involved.
Instructors: Djorgovski, Graham, Mahabal, Lombeyda.
Ay 121.
Radiative Processes.
9 units (3-0-6):
first term.
Prerequisites: Ph 106 bc, Ph 125 or equivalent (undergraduates).
The interaction of radiation with matter: radiative transfer, emission, and absorption. Compton processes, coherent emission processes, synchrotron radiation, collisional excitation, spectroscopy of atoms and molecules.
Instructor: Kulkarni.
Ay 122 abc.
Astronomical Measurements and Instrumentation.
9 units (3-0-6):
first, second terms.
Prerequisites: Ph 106 bc or equivalent.
Measurement and signal analysis techniques throughout the electromagnetic spectrum. Courses may include lab work and field trips to Caltech observatories. Ay 122 a concentrates on infrared, optical, and ultraviolet techniques: telescopes, optics, detectors, photometry, spectroscopy, active/adaptive optics, coronography. Imaging devices and image processing. Ay 122 b concentrates on radio through submillimeter techniques: antennae, receivers, mixers, and amplifiers. Interferometers and aperture synthesis arrays. Signal analysis techniques and probability and statistics, as relevant to astronomical measurement. Ay 122 c concentrates on X-ray through gamma-ray techniques.
Part c not offered 2024-25.
Instructors: Howard, Steidel, Hallinan, Kulkarni.
Ay 123.
Structure and Evolution of Stars.
9 units (3-0-6):
first term.
Prerequisites: Ay 101; Ph 125 or equivalent (undergraduates).
Thermodynamics, 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.
Instructor: El-Badry.
Ay 124.
Structure and Evolution of Galaxies.
9 units (3-0-6):
second term.
Prerequisites: Ay 21; Ph 106 or equivalent (undergraduates).
Stellar dynamics and properties of galaxies; instabilities; spiral and barred galaxies; tidal dynamics and galaxy mergers; stellar composition, masses, kinematics, and structure of galaxies; galactic archeology; galactic star formation; feedback from stars and super-massive black holes; circum-galactic medium.
Instructors: Hopkins, El-Badry.
Ay 125.
High-Energy Astrophysics.
9 units (3-0-6):
second term.
Prerequisites: Ph 106 and Ph 125 or equivalent (undergraduates).
High-energy astrophysics, the final stages of stellar evolution; supernovae, binary stars, accretion disks, pulsars; extragalactic radio sources; active galactic nuclei; black holes.
Instructor: Kasliwal.
Ay 126.
Interstellar and Intergalactic Medium.
9 units (3-0-6):
third term.
Prerequisites: 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.
Instructor: Ravi.
Ay 127.
Astrophysical Cosmology.
9 units (3-0-6):
third term.
Prerequisites: Ay 21; Ph 106 or equivalent (undergraduates).
Cosmology; extragalactic distance determinations; relativistic cosmological models; thermal history of the universe; nucleosynthesis; microwave background fluctuations; large-scale structure; inter-galactic medium; cosmological tests; galaxy formation and clustering.
Instructor: Steidel.
Ge/Ay 132.
Atomic and Molecular Processes in Astronomy and Planetary Sciences.
9 units (3-0-6):
second term.
Prerequisites: instructor's permission.
Fundamental aspects of atomic and molecular spectra that enable one to infer physical conditions in astronomical, planetary, and terrestrial environments. Topics will include the structure and spectra of atoms, molecules, and solids; transition probabilities; photoionization and recombination; collisional processes; gas-phase chemical reactions; and isotopic fractionation. Each topic will be illustrated with applications in astronomy and planetary sciences, ranging from planetary atmospheres and dense interstellar clouds to the early universe.
Given in alternate years; offered 2024-25.
Instructor: Blake.
Ge/Ay 133.
The Formation and Evolution of Planetary Systems.
9 units (3-0-6):
first term.
Review current theoretical ideas and observations pertaining to the formation and evolution of planetary systems. Topics to be covered include low-mass star formation, the protoplanetary disk, accretion and condensation in the solar nebula, the formation of gas giants, meteorites, the outer solar system, giant impacts, extrasolar planetary systems.
Instructor: Batygin.
Ge/Ay 137.
Planetary Physics.
9 units (3-0-6):
second term.
Prerequisites: Ph 106 abc, ACM 95/100 ab.
A quantitative review of dynamical processes that characterize long-term evolution of planetary systems. An understanding of orbit-orbit resonances, spin-orbit resonances, secular exchange of angular momentum and the onset of chaos will be developed within the framework of Hamiltonian perturbation theory. Additionally, dissipative effects associated with tidal and planet-disk interactions will be considered.
Instructor: Batygin.
Ay 141 abc.
Research Conference in Astronomy.
2 units (1-0-1):
first, second, third terms.
Oral reports on current research in astronomy, providing students an opportunity for practice in the organization and presentation of technical material. A minimum of two presentations will be expected from each student each year. In addition, students are encouraged to participate in a public-level representation of the same material for posting to an outreach website. This course fulfills the option communication requirement and is required of all astronomy graduate students who have passed their qualifying exam. It is also recommended for astronomy seniors; non-seniors can attend but cannot take the course for credit. Graded pass/fail.
Instructors: Steidel, Kasliwal, Hopkins.
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 for graduate students. 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 for graduate students. Graded pass/fail.
Ay 144.
Independent Writing in Astronomy.
3 units (0-0-3):
offered every term.
Prerequisites: Ay 142.
This course is intended to be taken by students conducting minor study in the Ay option, subsequent to a term of Ay 142 (Research in Astronomy and Astrophysics), or by students who have completed a SURF with an astronomy faculty member and are writing it up for publication. Students should sign up in the section of the faculty member who supervised the research project. Course requirements are (at minimum) bi-weekly meetings with the research adviser and preparation of a 5-20 page write-up of the work in the style of one of the major journals, such as ApJ/AJ or Science/Nature. This course is required as part of the Ay minor.
Instructor: Staff.
Ge/Ay 159.
Astrobiology.
9 units (3-0-6):
second term.
We approach the age-old questions "Why are we here?" and "Are we alone?" by covering topics in cosmology, the origins of life, planetary habitability, the detection of biosignatures, the search for extraterrestrial intelligence, and humanity's future in space. Specific topics include: the emergence of life at hydrothermal vents; the habitable zone and the Gaia hypothesis; the search for ancient habitable environments on Mars; icy satellites like Europa, Enceladus, and Titan as astrobiological prospects; and the hunt for atmospheric biosignatures on exoplanets.
Instructor: Yung.
Ay 190.
Computational Astrophysics.
9 units (3-0-6):
third term.
Prerequisites: Ph 20-22 (undergraduates).
Introduction to essential numerical analysis and computational methods in astrophysics and astrophysical data analysis. Basic numerical methods and techniques; N-body simulations; fluid dynamics (SPH/grid-based); MHD; radiation transport; reaction networks; data analysis methods; numerical relativity.
Instructors: Hopkins, Most.
Ay/Ge 198.
Special Topics in the Planetary Sciences.
6 units (2-0-4):
third term.
Topic for 2024-25 is Extrasolar Planets. Thousands of planets have been identified in orbit around other stars. Astronomers are now embarking on understanding the statistics of extrasolar planet populations and characterizing individual systems in detail, namely star-planet, planet-planet and planet-disk dynamical interactions, physical parameters of planets and their composition, weather phenomena, etc. Direct and indirect detection techniques are now completing the big picture of extra-solar planetary systems in all of their natural diversity. The seminar-style course will review the state of the art in exoplanet science, take up case studies, detail current and future instrument needs, and anticipate findings.
Instructor: Howard.
Ay 211.
Contemporary Extragalactic Astronomy.
9 units (3-0-6):
first term.
Prerequisites: Ay 123, Ay 124, and Ay 127.
Topics in extragalactic astronomy and cosmology, including observational probes of dark matter and dark energy; cosmological backgrounds and primordial element abundances; galaxy formation and evolution, including assembly histories, feedback and environmental effects; physics of the intergalactic medium; the role of active galactic nuclei; galactic structure and stellar populations; future facilities and their likely impact in the field.
Not offered 2024-25.
Ay 215.
Seminar in Theoretical Astrophysics.
9 units (3-0-6):
second term.
Course for graduate students and seniors in astronomy. Topic for 2022-23 will be compact binaries containing white dwarfs, neutron stars and black holes. Formation, mass transfer, accretion, X-ray and pulsar binaries, magnetic and wind interactions, mergers, gravitational waves. Students will be required to lead some discussions; homework will consist exclusively of reading and working through selected papers in preparation for discussions.
Not offered 2024-25.
Ay 218.
Extrasolar Planets.
9 units (3-0-6):
third term.
Ay 219.
Elements in the Universe and Galactic Chemical Evolution.
9 units (3-0-6):
second term.
Prerequisites: Ay 121, 123, 124, 126.
Survey of the formation of the elements in the universe as a function of cosmic time. Review of the determination of abundances in stars, meteorites, H II regions, and in interstellar and intergalactic gas. Overview of models of galactic chemical evolution. Participants will measure elemental abundances from the Keck spectrum of a star and construct their own numerical chemical evolution models.
Not offered 2024-25.