SPAT0007-2 : Variable stars

Study Programmes 2015-2016

SPAT0007-2

Variable stars

Duration :

20h Th, 10h Pr

Number of credits :

Master in space sciences (120 ECTS)		3

Lecturer :

Grégor Rauw

Language(s) of instruction :

English language

Organisation and examination :

Teaching in the first semester, review in January

Units courses prerequisite and corequisite :

Prerequisite or corequisite units are presented within each program

Course contents :

In astrophysics you are only allowed to watch your targets, you cannot manipulate them in a lab. Therefore, it is important to gather as much information as possible to understand the nature of the objects that are being investigated. In this context, temporal variability provides a precious tool.
The observational properties of many different categories of variable stars (including single and multiple objects) are presented. Various techniques to study these objects are described and the latest models derived from these observations are presented.
An important part of the course deals with multiple systems harbouring two or more stars. We consider the techniques used to infer fundamental stellar parameters (masses, radii,...) from the study of spectroscopic and eclipsing binaries. We also discuss interacting binaries, such as cataclysmic variables, novae, X-ray binaries,... For single stars, the lectures focus on the different categories of pulsating stars across the Hertzsprung-Russell diagram as well as their period-luminosity relations. The variability of massive stars, mainly due to structures in their stellar winds, is also described.

Learning outcomes of the course :

After completing this course, the students will be able to answer notably three major questions:

What are the general properties of variable stars?
How to extract the most relevant information from their spectra time-series and/or from their light curves?
How to interpret the observed variability?

Prerequisite knowledge and skills :

Good knowledge of mathematics, physics and classical mechanics.

Planned learning activities and teaching methods :

During two hand-on sessions, the students have the opportunity to analyze the light curve of an eclipsing binary system and the radial velocity curve of a spectroscopic binary using dedicated software.
Based on the techniques taught during the hand-on sessions , the students will do a personal project where they are asked to either prepare new observations of a variable star with the TIGRE robotic telescope, or to analyze such observations.

Mode of delivery (face-to-face ; distance-learning) :

The face-to-face lectures are usually scheduled as 3h/week during the first semester. Starting from the academic year 2015-2016, the course will be offered only during uneven years.