El-Gordo from Menanteau et al. (2012)

Physics 514: Radiative Processes
Spring 2024

Mondays and Wednesdays 2:00–3:20 pm, Serin 401
Instructor: Saurabh W Jha

Description

Electromagnetic phenomena in astrophysical systems. Radiative transfer. Radiation from moving charges. Emission mechanisms: bremsstrahlung, synchrotron, Compton scattering. Plasma effects. Atomic and molecular structure and spectroscopy.

Contact Information

Prof. Saurabh W Jha (he/him)
Room 315, Serin Physics Building, Busch campus
Email: saurabh[at]physics.rutgers.edu
Phone: 848-445-8962 (email preferred)

Office hours: Thursdays 3:30 to 4:30 pm, or by appointment

Textbook

The required textbook we will use is Radiative Processes in Astrophysics by Rybicki and Lightman. This is not always easy to find, so get your copy early. You may want to search for other formats of this book.

Supplementary textbooks (not required) include An Introduction to Modern Astrophysics, by Carroll & Ostlie, Theoretical Astrophysics, Volume I: Astrophysical Processes, by T. Padmanabhan, and The Physics of Astrophysics, Volume I: Radiation, by Frank H. Shu.

Assessment

We will have roughly weekly problem sets due on Fridays at 5pm in PDF format on Canvas. In working on the problem sets, you are encouraged to work in groups, though your submitted write-up should be your own. You must list your collaborators on the write-up. You are allowed to consult any outside sources (which, other than the course lecture notes or the textbook, must be cited), except that you may not examine problem set solutions from previous years of Physics 514 or other similar courses online. Any use of AI to assist with the problem sets must be cited, and you have to show me how you did it. Late problem sets will be accepted without penalty until Sunday evening at 11:59 pm. Solutions will be posted on Monday morning and no late problem sets will be accepted after the solutions are posted.

There will be one in-class midterm exam and a take-home final exam. There will also be a numerical group project, where you write the code to solve a particular problem, working in groups of 2 or 3 people.

The final grade will be calculated from the problem sets (50%), midterm exam (15%), numerical project (10%), and final exam (25%). The lowest problem set grade will be dropped in calculating the final grade.

Academic Integrity

Students are expected to maintain the highest level of academic integrity. You should be familiar with the university policy on academic integrity. Violations will be reported and enforced according to this policy. See also the department's page on academic integrity for graduate students.

Use of external website resources (such as Chegg.com or others) to obtain solutions to homework assignments or exams is cheating and a violation of the University Academic Integrity policy. Cheating in the course may result in grade penalties, disciplinary sanctions or educational sanctions. Posting homework assignments or exams to external sites without the instructor's permission may be a violation of copyright and may constitute the facilitation of dishonesty, which may result in the same penalties as cheating. 

The Rutgers honor pledge will be included on all major assignments for you to sign: On my honor, I have neither received nor given any unauthorized assistance on this examination/assignment.

Almost all original work is the intellectual property of its authors. In this course, this includes syllabi, lecture slides, recorded lectures, homework problems, exams, and other materials, in either printed or electronic form. You may not copy this work, post it online, or disseminate it in any way without the explicit permission of the instructor. Respect for the author's efforts and for the author’s intellectual property rights is an important value that members of the university community are expected to take seriously.

Schedule: Topics and Assignments

This schedule may be updated as the semester progresses.

Lecture
Date
Topics
Chapter
Assignment
1
Jan 17 (Wed)
radiative transfer
1
2
Jan 22 (Mon)
3
Jan 24 (Wed)
PS 1 due Jan 26
4
Jan 29 (Mon)
5
Jan 31 (Wed)
PS 2 due Feb 02
6
Feb 05 (Mon)
radiation fields
2
 
7
Feb 07 (Wed)
PS 3 due Feb 09
8
Feb 12 (Mon)
radiation from moving charges
3
9
Feb 14 (Wed)
PS 4 due Feb 16
10
Feb 19 (Mon)
11
Feb 21 (Wed)
relativity
4
PS 5 due Feb 23
12
Feb 26 (Mon)
13
Feb 28 (Wed)
5
PS 6 due Mar 01
exam
Mar 04 (Mon)
 in-class midterm exam
 
Mar 06 (Wed)
 
numerical project description due Mar 08
  Mar 11, 13 spring break     
14
Mar 18 (Mon)
bremsstrahlung
15
Mar 20 (Wed)
synchrotron radiation
6
PS 7 due Mar 22
16
Mar 25 (Mon)
17
Mar 27 (Wed)
Compton scattering;
inverse Compton
7
PS 8 due Mar 29
18
Apr 01 (Mon)
19
Apr 03 (Wed)
plasma effects
8
PS 9 due Apr 05
eclipse!
Apr 08 (Mon)
no class
 
 
20
Apr 10 (Wed)
atomic structure
9
PS 10 due Apr 12
21
Apr 15 (Mon)
 
 
 
22
Apr 17 (Wed)
radiative transitions
10
PS 11 due Apr 19
23
Apr 22 (Mon)
 
 
24
Apr 24 (Wed)
molecular structure/transitions 
11
PS 12 due Apr 26
25
Apr 29 (Mon)
numerical project presentations
numerical projects due
May 3 (Fri)
take-home final exam due

Detailed Topic List (to be modifed as the semester progresses)

Lectures 1-5. Fundamentals of radiative transfer: specific intensity, radiative transfer, optical depth, thermal radiation, Einstein coefficients, scattering, and diffusion.
Lectures 6, 7. Review of radiation fields: Maxwell's equations, electromagnetic waves, polarization, Stokes parameters, scalar and vector potentials.
Lecture 8, 9, 10. Radiation from moving charges: Lienard-Wiechart potentials, Larmor's formula, dipole approximation, multipole expansion, Thomson scattering.
Lectures 11, 12, 13. Relativistic covariance and kinematics: 4-vectors, relativistic mechanics, emission from relativistic particles, relativistic beaming.
Lecture 14 . Bremsstrahlung: non-relativistic free-free emission and absorption, relativistic bremsstrahlung.
Lectures 15, 16. Synchrotron radiation: spectral energy distribution, polarization, synchrotron self-absorption, cooling. Gamma-ray bursts.
Lectures 17, 18. Compton scattering: cross-section, inverse Compton scattering, spectral energy distribution, multiple scattering, Kompaneets equation, Sunyaev-Zeldovich effect.
Lecture 19. Plasma effects: plasma frequency, dispersion measure, Faraday rotation.
Lectures 20, 21. Atomic structure: one-electron systems, many-electron systems, fine structure, Zeeman effect, hyperfine structure, thermal equlibrium, Saha equation.
Lectures 22, 23. Radiative transitions: oscillator strengths, selection rules, transition rates, hydrogen recombination, line broadening.
Lecture 24. Molecular structure: electronic transitions, rotational transitions, vibrational transitions, combined spectra.
Lecture 25. Numerical project presentations. Course summary; applications of radiative processes in the astrophysical literature.

Resources

A list of physical and astronomical constants in cgs units.

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Students with disabilities should consult the department policy.


Astrophysics at RutgersDepartment of Physics and AstronomyRutgers University

Last updated: February 14, 2024 swj