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arXiv · 2606.13642

Search for High-Frequency Gravitational Waves via Geomagnetic Conversion with Radio Telescopes

Abstract

The detection of high-frequency gravitational waves (HFGWs) above 10 kHz provides a crucial probe of exotic astrophysical phenomena and new physics. We report the first search for HFGWs via their conversion to electromagnetic radiation through the inverse Gertsenshtein effect in Earth's magnetic field, utilizing radio telescopes including the Very Large Array (VLA) and the Atacama Large Millimeter/submillimeter Array (ALMA). Since no statistically significant signal is observed, we obtain new upper limits on the characteristic strain across the 1 GHz -- 1 THz band, with the most stringent constraint reaching $h_c \lesssim 10^{-18}$, improving upon existing bounds by up to three orders of magnitude. These results significantly advance the exploration of uncharted parameter space for exotic gravitational-wave sources, paving the way for future discoveries with next-generation facilities such as the Square Kilometre Array (SKA).

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BibTeXRIS

Hongliang Tian, Lei Wu, Xiaolong Yang, Qiang Yuan, Bin Zhu. 2026-06-11. Search for High-Frequency Gravitational Waves via Geomagnetic Conversion with Radio Telescopes. https://arxiv.org/abs/2606.13642

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