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arXiv · 2402.03984

Angular correlation and deformed Hellings-Downs curve from spin-2 ultralight dark matter

Rong-Gen Cai·Jing-Rui Zhang·Yun-Long Zhang
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Abstract

The pulsar timings are sensitive to both the nanohertz gravitational-wave background and the oscillation of ultralight dark matter. The Hellings-Downs angular correlation curve provides a criterion to search for stochastic gravitational-wave backgrounds at nanohertz via pulsar timing arrays. We study the angular correlation of the timing residuals induced by the spin-2 ultralight dark matter, which is different from the usual Hellings-Downs correlation. At a typical frequency, we show that the spin-2 ultralight dark matter can give rise to the deformation of the Hellings-Downs correlation curve induced by the stochastic gravitational wave background.

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Rong-Gen Cai, Jing-Rui Zhang, Yun-Long Zhang. 2024-02-06. Angular correlation and deformed Hellings-Downs curve from spin-2 ultralight dark matter. https://doi.org/10.1103/physrevd.110.044052

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