One of his graduate students, J. Bell, was charged with examining the output from the telescope. The current census of pulsars numbers over 700, and they have become important astrophysical laboratories. Some outstanding characteristics of pulsars are The interior of a pulsar is a neutron superfluid at densities of order that of nuclear matter, g cm . A neutron star is only slightly more than twice the size of its Schwarzschild radius so that general relativity is important in determining the structure of a neutron star.
Pulsars are compact, pulsed sources of polarized emission.
These propagation effects are a rich source of information about the intervening medium. Continued progress in using pulsars as high-precision laboratories will come with the deployment of more sensitive instruments and receivers, more sophisticated methods of analysis, a better understanding of the intervening medium, and discovery of additional objects and systems. In this thesis we describe the implementation of a genetic algorithm to search for planets around pulsars and demonstrate that it is superior to other methods that have been used previously to search for planets around pulsars. Further, since the optimal search parameters depend, in part, on the interstellar material along the lines of sight of interest, our results will aid in the detection of additional pulsars, particularly in the direction of the Galactic center. In the remainder of this chapter we provide a brief summary of propagation phenomena and their impact on pulsar search programs and analyses.