Origin of pulsar timing noise: possible correlations between pulsar spin-down rates and magnetospheric processes

English: Pulsars are extremely accurate clocks that allow us to explore certain unanswered questions in the elds of exotic compact forms of matter and gravitational wave as- trophysics. Pulsars that form part of a timing array can be used to detect stochastic gravitational wave (GWs) backgrounds produced by merging super-massive black holes by searching for systematic correlated delays in the arrival times of the pulses over decades. However, these GW backgrounds produce a small amplitude variation in the timing residuals of a pulsar over decades. Similar to the residual signature produced by GW, timing noise also exhibits a quasi-periodic timing residual signa- ture due to some unidenti ed variations in the pulsar's spin parameters. This study focused on the analysis of the timing noise phenomena observed in PSR J1326-5859. Several decades of timing and polarization data were analyzed and correlated in an attempt to model the observed timing noise signature. We propose that PSR J1326-5859 is coupled to a fossil disk that torques the star in a quasi stable manner and produces the observed spin-down evolution and polarization state changes.