Astronomy - Stellar Structure and Evolution.pdf

Lecture Notes on
Stellar Structure and
Evolution
Jørgen Christensen-Dalsgaard
Institut for Fysik og Astronomi, Aarhus Universitet
Sixth Edition
Fourth Printing
March 2008
ii
Preface
The present notes grew out of an introductory course in stellar evolution which I have
given for several years to third-year undergraduate students in physics at the University
of Aarhus. The goal of the course and the notes is to show how many aspects of stellar
evolution can be understood relatively simply in terms of basic physics. Apart from the
intrinsic interest of the topic, the value of such a course is that it provides an illustration
(within the syllabus in Aarhus, almost the first illustration) of the application of physics
to “the real world” outside the laboratory.
I am grateful to the students who have followed the course over the years, and to
my colleague J. Madsen who has taken part in giving it, for ments and advice;
indeed, their insistent urging that I replace by a more coherent set of notes the textbook,
supplemented by mentary and additional notes, which was originally used
in the course, is directly responsible for the existence of these notes. Additional input was
provided by the students who suffered through the first edition of the notes in the Autumn
of 1990. I hope that this will be a continuing process; ments, corrections and
suggestions for improvements are most e. I thank N. Grevesse for providing the
data in Figure , and P. E. Nissen for helpful suggestions for other figures, as well as
for reading menting on an early version of the manuscript. I also thank Bent
Christensen-Dalsgaard and T. M. Brown for their assistance in locating the Bradbury
reference in Chapter 2. The High Altitude Observatory, Boulder, Colorado is thanked for
hospitality during the Summer of 1990, where a substantial part of the notes were written.
Aarhus, August 1991
Jørgen Christensen-Dalsgaard
Preface to 4th edition
Relative to earlier edi