Pulsars as Astrophysical Laboratories for Nuclear and Particle Physics

Abstract

A forefront area of research concerns the exploration of the properties of hadronic matter under extreme conditions of temperature and density, and the determination of the equation of state--the relation between pressure, temperature and density--of such matter. Experimentally, relativistic heavy-ion collision experiments enable physicists to cast a brief glance at hot and ultra-dense matter for times as little as about $10^{-22}$ seconds. Complementary to this, the matter that exists in the cores of neutron stars, observed as radio pulsars, X-ray pulsars, and magnetars, is at low temperatures but compressed permanently to ultra-high densities that may be more than an order of magnitude higher than the density of atomic nuclei. This makes pulsars superb astrophysical laboratories for medium and high-energy nuclear physics, as discussed in this paper.Comment: 10 pages, 13 figures; Paper presented at the International School Of Nuclear Physics, 28th Course: Radioactive Beams, Nuclear Dynamics and Astrophysics, Erice-Sicily, 16-24 September 2006; to be published in Prog. Part. Nucl. Phy