Speaker
Delphine Perrodin
Description
Compact stars such as neutron star interiors are ideal laboratories for studying
nuclear matter at extremely high densities. Pulsars are highly-magnetized,
fast-rotating neutron stars that emit beams of electromagnetic radiation (ranging
from radio to gamma rays) which we observe as periodic "pulses" with extraordinary
regularity. Pulsar timing consists in the regular monitoring of the
times-of-arrival of these pulses, and allows us to determine many pulsar
properties with high precision, including orbital properties of pulsars in binary
systems. In particular, radio observations of pulsars have led to precise
measurements of neutron star masses, while X-ray observations of pulsars have
helped determine neutron star radii. Since each proposed equation of state (EOS)
of superdense nuclear matter in neutron stars leads to a unique neutron star
mass-to-radius relation, the EOS can be constrained by neutron star mass and
radius measurements from pulsar observations. We give an introduction to pulsar
timing, constraints on the EOS of neutron stars and on theories of gravity. We
also give an introduction on the planned Square Kilometre Array, which will allow
us to improve the constraint on the EOS of neutron stars by one order of
magnitude.
