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arXiv · 2310.08366

Constraints on the velocity of gravitational waves from NANOGrav 15-year data set

Yan-Chen Bi·Yu-Mei Wu·Zu-Cheng Chen·Qing-Guo Huang
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Abstract

General relativity predicts that gravitational waves propagate at the speed of light. Although ground-based gravitational-wave detectors have successfully constrained the velocity of gravitational waves in the high-frequency range, extending this constraint to the lower frequency range remains a challenge. In this work, we utilize the deviations in the overlap reduction function for a gravitational-wave background within pulsar timing arrays to investigate the velocity of gravitational waves in the nanohertz frequency band. By analyzing the NANOGrav 15-year data set, we obtain a well-constrained lower bound for the velocity of gravitational waves that $v \gtrsim 0.87\,c$, where $c$ is the speed of light.

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Yan-Chen Bi, Yu-Mei Wu, Zu-Cheng Chen, Qing-Guo Huang. 2023-10-12. Constraints on the velocity of gravitational waves from NANOGrav 15-year data set. https://doi.org/10.1103/physrevd.109.l061101

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