PX3244: Extragalactic Astrophysics
| School | Cardiff School of Physics & Astronomy |
| Department Code | PHYSX |
| Module Code | PX3244 |
| External Subject Code | 100425 |
| Number of Credits | 10 |
| Level | L6 |
| Language of Delivery | English |
| Module Leader | Professor Jonathan Davies |
| Semester | Spring Semester |
| Academic Year | 2014/5 |
Outline Description of Module
- To explain how the structure of our Galaxy can be determined experimentally.
- To compare the properties of our Galaxy with other galaxies.
- To introduce the basic physical ideas underlying models of galactic structure.
On completion of the module a student should be able to
- Explain how the structure and nature of our Galaxy can determined observationally.
- Describe the observed differences between galaxies of various types and discuss how these differences might arise.
- Discuss possible explanations of how structures like galaxies might have formed in the early Universe and how they can evolve into the galaxies we see today.
- Devise the Schecter luminosity function in terms of the absolute magnitude and use this to fit observational data.
- Calculate the surface densities of spiral galaxies using Freeman’s law.
- Derive Jean’s Mass and discuss why this can explain observed properties of galaxies.
- Use rotation curves for stars within galaxies.
How the module will be delivered
Lectures 22 x 1 hr, Exercises.
Skills that will be practised and developed
Problem solving. Mathematics. Analytical skills.
How the module will be assessed
Examination 80%. Coursework 20%. [Examination duration: 2 hours]
Assessment Breakdown
| Type | % | Title | Duration(hrs) |
|---|---|---|---|
| Exam - Spring Semester | 80 | Extragalactic Astrophysics | 2 |
| Written Assessment | 20 | Extragalactic Astrophysics | N/A |
Syllabus content
The Milky Way as a Galaxy: The historical development of ideas about the nature of our own Galaxy, stellar populations and distributions, gas (atomic and molecular hydrogen, etc.), dust (interstellar extinction), stellar kinematics, rotation, mass (Oort's model).
The Observed Properties of Other Galaxies: Galaxy types
- Elliptical galaxies – numbers, surface brightness distribution, stellar populations and metalicity, hot gas.
- Spiral galaxies – numbers, surface brightness distribution, spiral structure, stellar populations and metalicity, interstellar medium, rotation and dark matter.
- Irr and dwarf galaxies – Local group, numbers, star formation histories, dark matter.
- AGN and the unified model.
- The luminosity function; the Tully-Fisher relation; the chemical evolution of galaxies.
The distribution of galaxies in the Universe: galaxy clustering, morphology density relation, properties of clusters, x-ray gas, clustering scale, two-point correlation function, comments on large scale structure and comparisons with simulations.
Galaxy Formation and evolution: Simple ideas of galaxy formation; the Jeans mass; hierarchical clustering versus monolithic collapse, observations that support the standard model – galaxy number counts, downsizing, properties of high redshift galaxies, the star formation history of the Universe.
Essential Reading and Resource List
Galactic Astronomy by Binney and Merrifield (Princeton University Press).
Background Reading and Resource List
Not applicable.