Statistical Analysis of I Stokes Parameter of Millisecond Pulsars

TL;DR

This study uses DFA and box counting to analyze polarization pulse profiles of millisecond pulsars, revealing their fractal and persistent nature, and comparing their complexity to normal pulsars.

Contribution

It introduces a combined DFA and box counting approach to characterize the fractality and complexity of MSPs' polarization profiles, highlighting differences from normal pulsars.

Findings

MSPs' PPPs are persistent and fractal in nature.

Isolated MSPs have more complex PPPs than binary MSPs.

MSPs exhibit more complex PPPs than normal pulsars due to smaller emission cones.

Abstract

Using Detrended Fluctuation Analysis (DFA) and box counting method, we test spacial correlation and fractality of Polarization Pulse Profiles (PPPs) of 24 millisecond pulsars (MSPs) which were observed in Parkes Pulsar Timing Array (PPTA) project. DFA analysis indicates that MSPs' PPPs are persistent and the results of box counting method confirm the fractality in the majority of PPPs. A Kolmogorov-Smirnov test indicates that isolated MSPs have more complex PPPs than binary ones. Then we apply our analysis on a random sample of normal pulsars. Comparing the results of our analysis on MSPs and normal pulsars shows that MSPs have more complex PPPs which is resulted from smaller angular half-width of the emission cone and more peaks in MSPs PPPs. On the other hand, high values of Hurst exponent in MSPs confirm compact emission regions in these pulsars.