Is there potential complementarity between LISA and pulsar timing?

TL;DR

This paper explores how LISA gravitational wave observations of SMBH mergers could complement pulsar timing arrays by improving parameter estimation and guiding searches for inspiral signals.

Contribution

It proposes a method to use LISA data to enhance pulsar timing GW searches and suggests future research directions involving ring-down observations for massive black hole mergers.

Findings

LISA can provide tight parameter constraints for pulsar timing GW signals.

Using LISA data could improve the detection prospects of SMBH inspirals in pulsar timing arrays.

Future work includes leveraging ring-down signals for massive black hole mergers.

Abstract

We open the discussion into how the Laser Interferometer Space Antenna (LISA) observations of supermassive black-hole (SMBH) mergers (in the mass range ~10^6-10^8 Msun) may be complementary to pulsar timing-based gravitational wave searches. We consider the toy model of determining pulsar distances by exploiting the fact that LISA SMBH inspiral observations can place tight parameter constraints on the signal present in pulsar timing observations. We also suggest, as a future path of research, the use of LISA ring-down observations from the most massive (>~ a few 10^7 Msun) black-hole mergers, for which the inspiral stage will lie outside the LISA band, as both a trigger and constraint on searches within pulsar timing data for the inspiral stage of the merger.