Abstract
In active stars the gravitational compressive pressure is balanced by the pressure due to the thermal motion of particles and to that of photons. This balance is maintained as long as the fusion nuclear reactions in the interior of the star take place. When the nuclear fuel is exhausted the mighty gravity compresses the star to a black hole, unless the pressure of the quantum kinetic energy of either the electrons (case of white dwarfs) or the neutrons (case of pulsars) is enough to balance the gravitational pressure. The lower limit of the mass of an active star is about 0.08 times the mass of the Sun. The upper limit is probably of the order of 100 times the mass of the Sun.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
Stellar winds, powered by radiation pressure, occur during the whole life of an active star although at a low rate; this rate is greatly accelerated during the period of instability.
- 2.
It is assumed here that the mass \( M^{\prime} \) is large enough, e.g., larger than 1055 m u , so that the gravitational energy dominates over the Coulomb energy.
- 3.
It is not unusual for a dead star to suck up mass from a companion star so that its mass \( M^{\prime} \) to be larger than its remaining mass just after the end of its active cycle.
- 4.
The neutrinos and antineutrinos produced in these reactions will not be retained within the system.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2011 Eleftherios N. Economou
About this chapter
Cite this chapter
Economou, E.N. (2011). Stars Dead Or Alive. In: A Short Journey from Quarks to the Universe. SpringerBriefs in Physics, vol 1. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-20089-2_12
Download citation
DOI: https://doi.org/10.1007/978-3-642-20089-2_12
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-20088-5
Online ISBN: 978-3-642-20089-2
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)