Syllabus – Spring 2003 – Astronomy G9001

Interstellar Medium and Star Formation

Mondays 1:10-3:55 PM

1332 Pupin Lab

Instructor: Mordecai-Mark Mac Low

Office hours by appointment

Department of Astrophysics Telephone: 212-496-3443

American Museum of Natural History Fax: 212-769-5007

79^th Street at Central Park W. Email: mordecai@amnh.org

New York, NY, 10024-5192

Summary

This course will cover the properties and behavior of the interstellar gas in our own and external galaxies, both modern and primordial, with a particular focus on how stars eventually form from that gas. Numerical methods for studying interstellar gas dynamics will be heavily emphasized. This will not be at the cost of understanding the observational evidence (with luck), but atomic and molecular physics and radiative transfer may get somewhat less attention than they deserve in a course of this nature.

Topics

ISM Components: gas, dust, cosmic rays, magnetic fields

Energetics: radiative heating and cooling, mechanical driving, turbulent flows, magnetic pressure, cosmic ray pressure

Extent: vertical distribution, radial structure, infalling material, comparison among galaxies

Structure: clouds vs. turbulent continuum, ionization, stellar winds and supernovae

Molecular Clouds: formation, structure, extent

Star Formation: gravitational instability, support against gravity, accretion, disks, winds and jets, multiplicity, IMF, star formation rate

Dust: Formation and destruction, radiative properties, role in molecule formation

Magnetic Fields: Dynamo mechanisms, interaction with ISM, structure and observation

Cosmic Rays: Acceleration in shocks, composition, escape from galaxy, interactions with ISM

Observational Methods: spectral absorption and emission lines, X-ray emission and spectra, HI lines, thermal and nonthermal radio continuum emission, infrared and submm emission, gamma ray emission

Numerical Methods: Eulerian grid-based MHD (ZEUS), Lagrangian particle-based hydro (GADGET), Eulerian multi-grid adaptive mesh refinement (Flashcode), photoionization (Cloudy), perhaps others if time permits

Classes

As a three-hour lecture would be overwhelming for all involved, classes will be structured with an initial hour of lecture on science, then discussion of reading, and finally 45 minutes on more technical issues such as numerical techniques or observational methods.

Exercises

As necessary, I’ll assign practical or theoretical exercises using the tools that are taught here. Primarily these will be to learn the properties of different numerical methods, but a couple of them may be more focused on analytic work or techniques for analysis of observations. I will accept them up to a week late without penalty, but not beyond that.

Numerical Project

A major part of the assigned work in this course will be a numerical project. This will likely be a gas dynamics computation, but I will also consider proposals based on observational data that require substantial computing to reduce or analyze. These may be done alone or in groups. However, a group project should have clearly identified tasks assigned to each member. These projects do not need to be original research: reproduction of an interesting published result is fine. To try to avoid having the projects both started and completed in the 24 hours before they are due, I’ll request the following intermediate reports:

Feb 24: Written proposal describing work to be done (1-3 pp.). I’ll provide feedback on practicality and interest.

Mar 10: Oral presentation of final project proposals to class.

Apr 7: Proof-of-concept results in written report (2-4 pp., including figures)

Apr 28: Oral presentation of projects to class in conference format (10-15 minute talks)

May 5: Project reports due

Grading

Grades will be assigned according to the following criteria:

Project (50%)

A: Challenging project related to current research, written up in a coherent paper referencing the research literature

B: Simpler project reproducing standard analytic result, written up clearly, or more challenging project, presented poorly or showing serious computational problems

C: Partially completed project with basic writeup.

F: Project blown off.

Exercises (30%)

A: Exercise completed and presented clearly.

B: Partial success in computation, or incoherent presentation of completed work

C: Attempt at exercise documented

F: Allergic to exercise

Participation (20%)

A: Familiar with assigned reading, asks questions that address main points or key weaknesses, participates in discussion of others’ questions.

B: Has done assigned reading, can discuss it, but remains unclear on what the important points are, and how it fits into the bigger picture.

C: Skimmed reading, opens mouth during discussion, perhaps shouldn’t have.

F: Will only give name, rank, and serial number during discussion.

Needless to say, adherence to professional standards of conduct in research is expected of everyone in the course. Falsification of data or plagiarism will lead to failure of the course. (Strange as it may seem, I probably have to give advance warning of this.) The American Physical Society has a comprehensive statement on research standards at http://www.aps.org/statements/02.2.html, which I encourage you to read if you have not.