A simple optimisation for the MeerKAT Pulsar Timing Array

TL;DR

This paper presents a greedy algorithm to optimize pulsar observation schedules in the MeerKAT Pulsar Timing Array, resulting in approximately 20% increased signal-to-noise ratio for gravitational wave detection within a fixed total observation time.

Contribution

It introduces a simple, effective optimization method for pulsar observation scheduling that enhances gravitational wave signal detection sensitivity.

Findings

Schedule adjustments can increase S/N by about 20%.

Minimal disruption to existing observation strategies.

Method demonstrates potential for improved GW detection sensitivity.

Abstract

The goal of the MeerKAT radio telescope's pulsar timing array programme (MPTA) is the detection of gravitational waves (GWs) of nanohertz frequencies. Evidence for such a signal was recently announced by the MPTA and several other pulsar timing array (PTA) consortia. Given an array of pulsars and an observation strategy, we consider whether small adjustments to the observing schedule can provide gains in signal-to-noise ratio (S/N) for a stochastic GW background signal produced by a population of massive black hole binaries. Our approach uses a greedy algorithm to reallocate available integration time between pulsars in the array. The overall time dedicated to MPTA observing is kept constant so that there is only minimal disruption to the current observation strategy. We assume a GW signal consistent with those reported. For the sake of demonstrating our method, we also make several simplifying assumptions about the noise properties of the pulsars in the MPTA. Given these assumptions, we find that small adjustments to the observing schedule can provide an increased S/N by $\approx 20\%$ for a $10\,{\rm yr}$ PTA lifespan.