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arXiv · 2302.11796

Constraining gravitational wave propagation using pulsar timing array correlations

Reginald Christian Bernardo·Kin-Wang Ng
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Abstract

Pulsar timing arrays (PTA) are a promising probe to the cosmologically novel nanohertz gravitational wave (GW) regime through the stochastic GW background. In this work, we consider subluminal GW modes as a possible source of correlations in a PTA, utilizing the public code PTAfast and the 12.5 years correlations data by NANOGrav, which we hypothesize are sourced by GWs. Our results show no evidence in support of tensor- or vector-induced GW correlations in the data, and that vector correlations are disfavored. This places an upper bound to the graviton mass, $m_{\rm g} \lesssim 10^{-22}$ eV, characteristic of the PTA GW energy scale.

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Reginald Christian Bernardo, Kin-Wang Ng. 2023-02-23. Constraining gravitational wave propagation using pulsar timing array correlations. https://doi.org/10.1103/physrevd.107.l101502

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