Beyond the Chandrasekhar limit: Structure and formation

of compact stars

DIPANKAR BHATTACHARYA

Inter-University Centre for Astronomy and Astrophysics, Post Bag No. 4, Ganeshkhind,

Pune 411 007, India

E-mail: dipankar@iucaa.ernet.in

Abstract. The concept of limiting mass, introduced by Chandrasekhar in case of white dwarfs,

plays an important role in the formation and stability of compact objects such as neutron stars and

black holes. Like white dwarfs, neutron stars have their own mass limit, and a compact configuration

would progress from one family to the next, more dense one once a mass limit is crossed. The mass

limit of neutron stars depends on the nature of nuclear forces at very high density, which has so

far not been determined conclusively. This article reviews how observational determinations of the

properties of neutron stars are starting to impose significant constraints on the state of matter at high

density.

Keywords. S Chandrasekhar; limiting mass; neutron star; equation of state.

PACS Nos 97.60.Jd; 26.60.Kp