SUPERDENSE
STELLAR MATTER AND COMPACT STAR STRUCTURE
Germán Lugones and Jorge
E. Horvath
Instituto
de Astronomia, Geofísica e Ciências Atmosféricas
Universidade
de São Paulo, Brasil
The study of superdense
stellar matter and the determination of the equation of state at high densities
(specially in the low-temperature domain) is of key importance for our
understanding of the physics of compact stars. In the last few years, the
overlap of areas such as nuclear physics, particle physics and relativistic
astrophysics and the increasing amount of data from the new generation of
orbiting observatories (Hubble, RXTE, Chandra, XMM) have contributed enormously
in this way. The global properties of compact stars such as masses and radii
are known to be sensitive to the adopted microscopic model for the particle
interactions and thus to the equation of state. Hence, by means of comparing
theoretically determined values for these quantities with observed ones one may
be able to constrain the behavior of superdense matter from the observational
neutron star data. In this work we shall concentrate on the behavior of
superdense stellar matter in the light of the last theoretical improvements of
the phase diagram of hadron matter at high densities. We shall also explore the
consequences on the general relativistic models of compact stars with special
emphasis in the possible observational signals. This features may be
interesting in view of some recent observations claming the existence of exotic
and/or deconfined phases in some nearby neutron stars.