AS5522 Stellar Physics

Academic year

2024 to 2025 Semester 2

Further information on which modules are specific to your programme.

Key module information

SCOTCAT credits

15

The Scottish Credit Accumulation and Transfer (SCOTCAT) system allows credits gained in Scotland to be transferred between institutions. The number of credits associated with a module gives an indication of the amount of learning effort required by the learner. European Credit Transfer System (ECTS) credits are half the value of SCOTCAT credits.

SCQF level

SCQF level 11

The Scottish Credit and Qualifications Framework (SCQF) provides an indication of the complexity of award qualifications and associated learning and operates on an ascending numeric scale from Levels 1-12 with SCQF Level 10 equating to a Scottish undergraduate Honours degree.

Availability restrictions

Available only to students on MSc Astrophysics.

Module Staff

TBC

This information is given as indicative. Staff involved in a module may change at short notice depending on availability and circumstances.

Module description

This module develops the physics of stellar interiors and atmospheres from the basic equations of stellar structure and radiative transfer concepts developed in Nebulae and Stars I. Topics include: the equation of state that provides pressure support at the high temperatures and densities found in normal and white-dwarf stars; the interaction of radiation with matter, both in terms of radiation-pressure support in super-massive stars and in terms of the role of opacity in controlling the flow of energy from the stellar interior to the surface; the equation of radiative transfer and the effects of local temperatures, pressures and velocity fields on the continuum and line absorption profiles in the emergent spectrum. Computer-aided tutorial exercises illustrate the computational schemes that represent one of the triumphs of late twentieth-century physics, in their ability to predict the observable properties of a star from its radius and luminosity, which in turn are determined by its mass, age and chemical composition.

Relationship to other modules

Pre-requisites

STUDENTS MUST BE REGISTERED FOR MSC ASTROPHYSICS.

Co-requisites

YOU MUST ALSO TAKE AS5500

Assessment pattern

2-hour Written Examination = 75%, Coursework = 25%

Re-assessment

Oral re-assessment = 100%, capped at grade 7

Learning and teaching methods and delivery

Weekly contact

3 lectures occasionally replaced by whole-group tutorials.

Scheduled learning hours

33

The number of compulsory student:staff contact hours over the period of the module.

Guided independent study hours

117

The number of hours that students are expected to invest in independent study over the period of the module.

Additional information from school

Aims & Objectives

Develop a deeper understanding of all physical processes that are important in the atmospheres and interiors of stars to explain their observed spectra, their internal structure and their evolution.

 

Learning Outcomes

By the end of the module the students will be able to:

 

  • Solve the equation of radiation transfer for static, plane parallel model atmospheres in the gray atmosphere approximation, both analytically and numerically.
  • Explain limb darkening in stellar atmospheres, and continuum and spectral line
  • Understand the concept of LTE and the conditions where it applies.
  • Understand the concept of the curve of growth and its significance for measuring stellar properties and element
  • Be able to define and calculate Jeans' masses and densities.
  • Be able to write down and explain the terms in the equations of stellar structure and solve them using simple numerical techniques.
  • Understand the equation of state that provides pressure support in stellar interiors.
  • Understand what is meant by a homologous model and apply it to solve the equations of stellar
  • Understand and describe nuclear burning in stars including CNO cycle and pp-chain.
  • Understand and describe stellar properties on the main sequence and explain post main sequence evolution and the fate of stars.

 

Synopsis

This module runs in parallel with AS4012.  All lectures and tutorials are shared with the AS4012 students, and the same assessed computational homework projects are offered.

 

The course is organised in two parts: stellar atmospheres (11 lectures) and stellar interiors (10 lectures). There are ten weekly workshop sessions taking place in the lecture room with exam-like questions, which are distributed one week prior to the workshop sessions. AS5522 students are required to carry out both of the assessed computational homework exercises to self-compute simple models for the emergent spectrum and the inner structure of solar-like stars using Python.  These count count 12.5% each (totalling 25%) towards the module grade.

 

 

Additional information on workshops and continuous assessment.

 

Please note that the definitive arrangements for continuous assessment will be communicated within the module.  This section is intended to give an indication of the likely breakdown and timing of the continuous assessment.

 

The ten workshops develop exam-style problem-solving skills. The questions will be distributed about one week prior to the tutorial sessions. Students will be subdivided into small groups in the workshops to discuss and compare their solutions. Complete solutions of all exam-style questions will be made available to the students afterwards on Moodle.  

 

The deadlines for submitting the assessed computational homework are likely to be towards the end of weeks 5 and 11.

 

Recommended Books

Please view University online record:

http://resourcelists.st-andrews.ac.uk/modules/as4012.html

 

General Information

Please also read the general information in the School's Astrophysics MSc handbook.