JPL pulsar timing observations. IV - Excess phase noise

Abstract

Previously published tables of geocentric arrival times for 24 pulsarscovering a 12 year span are extended here to 14.5 years. The listof pulsars is extended by nine, most of which were observed for about4 years. Known positins of these new objects are confirmed, and limitson the proper motions are obtained. Large phase excursions in PSR0525 + 21 are found. The orbital parameters of the binary pulsar0820 + 02 are tentatively confirmed. Short-term timing noise in excessof that expected from receiver considerations alone is established.Variations in the timing residuals for the original 24 pulsars areanalyzed for correlations with other observable parameters. Littlesignificant correlation with changes in pulse shape or energy orwith the drift correction is found on time scales of 500 pulses orlonger.