Course Syllabus
| Meeting Days: | Tuesday & Thursday | Location: | JFB 325 |
| Meeting Time: | 10:45 am to 12:05 pm | Semester: | Fall 2024 |
| Instructor: | Tanmoy Laskar | Office: | INSCC 320 |
| Door Code: | 07734 | Office Hours: | Tue 3-4pm, or by appointment |
Course Description
A core course intended for graduate students of Physics & Astronomy. This course explores high-energy phenomena in a variety of astrophysical settings, including within diffuse plasmas and around compact objects. The physical processes producing radiation and particles will be introduced, and techniques for their detection in the X-ray, gamma ray, and cosmic ray regimes will be discussed. Topics include accretion disks, pulsars, non-magnetized neutron stars, binary X-ray sources, black holes, supernovae and supernova remnants, gamma ray bursts, gravitational wave sources, clusters of galaxies, and active galactic nuclei.
Course Objectives and Learning Outcomes
By the end of this course, you will be able to:
- Demonstrate a broad overview and understanding of high-energy processes and phenomena in astrophysics.
- Develop an intuition on how various high-energy phenomena are interrelated, and the connections between high-energy phenomena, radiation mechanisms, and astrophysical sources & objects.
- Apply the physics of the relevant radiation mechanisms to derive astrophysical properties of the sources and phenomena of interest.
Reference Textbooks:
[HEA]: High-Energy Astrophysics, 3rd Edition by Malcolm Longair (available through inclusive access)
[RL]: Radiative Processes in Astrophysics by Rybicki & Lightman (available for free from Wiley; Files section)
[GG]: Radiative Processes in High-Energy Astrophysics by Gabriele Ghisellini https://arxiv.org/pdf/1202.5949
I recommend that you opt out of inclusive access for Rybicki and Lightman, since the book is available for free from the publisher and I have left a copy for you in the Files section. I recommend that you opt in to inclusive access for High-Energy Astrophysics, since this is a useful book and I will make several references to it throughout. If you already have a physical or electronic copy of HEA, feel free to opt out of this one as well. Note that HEA uses SI units and RL uses cgs units #funtimes.
Teaching & Learning Methods
Our two meetings per week will primarily be devoted to lectures. I hope to employ active learning methods (e.g. discussions and labs) as I figure out the associated logistics. Please stay engaged and flexible as we work this out!
Course schedule
This is a draft schedule for the class and is subject to change as the semester progresses. My aim is to be responsive to your needs as senior students, so if there is something you want to spend more time on, please let me know!
Text in italics below refers to
HEA: High Energy Astrophysics, 3rd Edition by Malcolm Longair
RL: Rybicki & Lightman, Radiative Processes in Astrophysics (available for free from Wiley; Files section)
| Week # | Dates (Tue & Thu) | Contents | Assignment Due |
| Week 1 |
Aug 20 Aug 22 |
Part I: High-energy Radiative Processes 1. Introduction: opening quiz, course policies, HEA mind map 2. Fundamentals of radiative transfer: Specific intensity, conservation of intensity, flux density, spectral energy distributions, fluence, luminosity |
Assignment 1 Due (Aug 21) |
| Week 2 |
Aug 27
|
3. Black bodies & thermal emission: volume emissivity (emission coefficient), absorption coefficient, radiative transfer equation in the presence of emission & absorption and its formal solution, blackbody radiation; brightness, color, and effective temperatures, Kirchhoff's law 4. Thomson scattering: Thomson cross section, Eddington luminosity, Eddington accretion. |
Assignment 3 Due |
| Week 3 |
Sep 03
Sep 05
|
5. Photoelectric absorption: absorption edges, effect on X-ray observations, X-ray spectroscopy with XSPEC. 6. Thermal Bremsstrahlung: spectral emissivity, total power, free-free absorption |
Assignment 4 Due
|
| Week 4 |
Sep 10
Sep 12
|
7. Particle in a magnetic field: gyrofrequency, gyroradius 8. Inverse Compton Scattering: energy transfer, IC in an isotropic photon field, IC energy loss rate, IC from a thermal population of charged particles |
Assignment 5 Due
|
| Week 5 |
Sep 17
Sep 19
|
9. Inverse Compton Spectra: single particle IC spectrum, synchrotron self-Compton, thermal Comptonization, Compton y-paramater, Kompaneets equation, Sunyaev-Zeldovich effect 10. Cherenkov radiation |
Assignment 6 Due
|
| Week 6 |
Sep 24
Sep 26
|
11. Pair production: pair loading, photon-nucleon pair production, air showers 12. Cosmic rays: energy spectrum, GZK cutoff, detection techniques, composition, trapping radius, solar modulation |
Assignment 7 Due (Sep 25)
|
| Week 7 |
Oct 01
Oct 03 |
13. Midterm exam 1 Part II: High-energy Astrophysical Sources 14. Sources and Processes in High-energy Astrophysics: an overview |
|
| Oct 08, Oct 10 | (Fall Break, no class) | Assignment 8 Due (Midsem survey, Oct 7) | |
| Week 8 |
Oct 15
Oct 17
|
15. Non-relativistic shocks: planar, perpendicular, non-magnetised shocks in polytropic fluids, conserved quantities, shock jump conditions, strong shocks 16. Non-relativistic shocks: reverse shocks |
Midterm recovery due
|
| Week 9 |
Oct 22 Oct 24 |
17. Diffusive shock acceleration: first-order Fermi process, energy gain per acceleration cycle, differential energy spectrum 18. Relativistic jets: superluminal motion, relativistic Doppler effect, solution to the compactness problem, jet launching mechanisms |
Final Project Topic sel. due (Oct 24) Assignment 9 Due (Oct 25) |
| Week 10 |
Oct 29 Nov 01 |
19. Relativistic shocks: shock jump conditions, strong shocks 20. Relativistic shocks: relativistic blast waves |
|
| Week 11 |
Nov 05
Nov 07
|
21. Gravitational waves: Introduction to gravitational waves, analogy with EM radiation, quadrupole formula, strain, GW polarization, metric tensor, gravitational wave equation and general solution. Readings:
22. Compact binary mergers: GW luminosity of a binary system, frequency of emission, GW detectors Electromagnetic counterparts: Short gamma-ray bursts, kilonovae, GW170187 (GW, GRB, KN discovery; afterglow discovery, superluminal motion, jet structure) |
|
| Week 12 |
Nov 12
Nov 14 |
23. Active galactic nuclei - jets: radio galaxies, core vs lobe emission, FR1 and FR2 sources, FIR-radio correlation, radio-mode feedback, giant radio galaxies, quasars, blazars (hadronic vs leptonic models, neutrinos), Seyfert galaxies, AGN unification model 24. Midterm Exam 2 |
|
| Week 13 |
Nov 19 Nov 21 |
25. Detectors & Observational Techniques 26. Topics in High-energy Astrophysics |
|
| Week 14 |
Nov 26 |
27. Conclusions & closure: Questions, Quiz |
|
| Week 15 | Dec 03 Dec 05 |
28. Student presentations 29. Student presentations |
|
Term-time feedback
If you have any feedback during the semester, please feel free to send it through this anonymous feedback form.
Course Components & Final Grade
- Participation: 10%
- Assignments: 50%
- Mid-term exams: 10%
- Final project: 30%
Students are expected to be familiar with any assigned readings prior to class, assignment due dates, and all course policies outlined in this syllabus.
Course Assessment Structure
Attendance and Participation (10%): Part of the final grade will include in-class participation via answering questions and involvement in discussions, and may include pre-class reading assignments. Attendance at course meetings is expected (see attendance policy below).
Assignments (50%): Most of the grade for this class will be based on regular assignments to be submitted through Gradescope.
Late assignment policy: You may submit one assignment late anytime during the semester, without penalty. Further late assignments will accrue 15% penalty per day (unless a prior agreement is made with me), until the assignments are returned or discussed in class (whichever comes first). At that point, no late assignments will be accepted for credit, but they may still be turned in for feedback. If you intend to submit an assignment after the due date and avail of this waiver, you must communicate your intention to do so via a Canvas message prior to the assignment submission deadline.
Mid-term exams (10%): Two mid-term exams will be held to consolidate our understanding of high-energy processes.
Final project (30%): In your final project, you will explore and summarize the state of the art in a sub-field of high-energy astrophysics via a presentation and a write-up. Further details will be available on Canvas.
Final exam: There will be no final exam in this course.
Grade scale: The following is the minimum letter grade you will receive based on the percentage of points.
93–100 (A), 90–92.9 (A-), 87–89.9 (B+), 83–86.9 (B), 80–82.9 (B-), 77–79.9 (C+), 73–76.9 (C), 70–72.9 (C-), 67–69.9 (D+), 60–66.9 (D), Below 60 (E).
This syllabus is not a binding legal contract, but is meant to serve as an outline and guide for our course. Please note that the Instructor(s) may modify the syllabus and course schedule with reasonable notice to accommodate the needs of our class. Any changes will be announced in class and posted on Canvas.
Policies and Resources
Policy on absences. You are allowed two absences with no questions, a further three excused absences (these much be communicated and agreed upon a week in advance; familiarity with the material is a valid reason to request an excused absence), and three additional health-related absences (communicated within 48 hours) throughout the semester (maximum 8 absences from our 29 course meetings). Further absences will reduce your grade by one percentage point for each absence. Three late attendances (>15 min) will count as an absence.
The Americans with Disabilities Act. The University of Utah seeks to provide equal access to its programs, services, and activities for people with disabilities. If you will need accommodations in this class, reasonable prior notice needs to be given to the Center for Disability Services, 162 Olpin Union Building, (801) 581-5020. CDS will work with you and the instructor to make arrangements for accommodations. All written information in this course can be made available in an alternative format with prior notification to the Center for Disability Services.
University Safety Statement. The University of Utah values the safety of all campus community members. To report suspicious activity or to request a courtesy escort, call campus police at 801-585-COPS (801-585-2677). You will receive important emergency alerts and safety messages regarding campus safety via text message. For more information regarding safety and to view available training resources, including helpful videos, visit safeu.utah.edu.
Addressing Sexual Misconduct. Title IX makes it clear that violence and harassment based on sex and gender (which includes sexual orientation and gender identity/expression) is a civil rights offense subject to the same kinds of accountability and the same kinds of support applied to offenses against other protected categories such as race, national origin, color, religion, age, status as a person with a disability, veteran’s status or genetic information. If you or someone you know has been harassed or assaulted, you are encouraged to report it to the Title IX Coordinator in the Office of Equal Opportunity and Affirmative Action, 135 Park Building, 801-581-8365, or the Office of the Dean of Students, 270 Union Building, 801-581-7066. For support and confidential consultation, contact the Center for Student Wellness, 426 SSB, 801-581-7776. To report to the police, contact the Department of Public Safety, 801-585-2677(COPS).
Diversity Statement by Instructor. I am an advocate for social justice, and stand in support of compassion, dignity, equity, inclusion, and justice for all individuals regardless of color, race/ethnicity, sexual orientation, religion, language, socioeconomic status, ability, gender identity or expression, immigration status, or any type of marginalization. I stand against individual and systemic racism in all its various forms.
Mental Health Support Statement by Instructor. If you are struggling with this course in any way, please reach out and let me know how I can help you. If you need additional help beyond this course, please contact campus mental health resources.
Course Summary:
| Date | Details | Due |
|---|---|---|