Ensemble Pulsar Time Scale

TL;DR

This paper introduces an optimal Wiener filtration algorithm for ensemble pulsar time scales that improves the stability of pulsar-based timekeeping by separating clock and pulsar contributions, outperforming classical methods.

Contribution

The paper presents a novel Wiener filtration approach for ensemble pulsar time scales, enhancing stability by effectively isolating clock signals from pulsar noise.

Findings

Improved fractional instability of the ensemble time scale.

Method outperforms classical weighted averaging.

Potential to reach instability levels of ~10^{-16}.

Abstract

The algorithm of the ensemble pulsar time scale (PT$_{\rm ens}$) based on the optimal Wiener filtration method has been proposed. This algorithm allows the separation of the contributions to the post-fit pulsar timing residuals of the atomic clock and pulsar itself. Filters were designed with the use of the cross-spectra of the timing residuals. The method has been applied to the timing data of six millisecond pulsars. Direct comparison with the classical method of the weighted average showed that use of the optimal Wiener filters before averaging allows noticeably to improve the fractional instability of the ensemble time scale. Application of the proposed method to the most stable millisecond pulsars with the fractional instability $\sigma_z < 10^{-15}$ may improve the fractional instability of PT$_{\rm ens}$ up to the level $\sim 10^{-16}$.