High-Frequency Gravitational Waves (HFGWs) constitute a unique window on the early Universe as well as exotic astrophysical objects. While the current gravitational wave experiments are more dedicated to the low frequency regime, the graviton conversion into photons in a strong magnetic field constitutes a powerful tool to probe HFGWs. In this paper, we show that neutron stars, due to their extreme magnetic field, are a perfect laboratory to study the conversion of HFGWs into photons. Using realistic models for the galactic neutron star population, we calculate for the first time the expected photon flux induced by the conversion of an isotropic stochastic gravitational wave background in the magnetosphere of the ensemble of neutron stars present in the Milky Way. We compare this photon flux to the observed one from several telescopes and derive upper limits on the stochastic gravitational wave background in the frequency range 108 Hz–1025 Hz. We find our limits to be competitive in the frequency range 108 Hz–1012 Hz.

中文翻译：

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来自银河系中子星的高频引力波范围


高频引力波 （HFGW） 构成了早期宇宙以及奇异天体物理天体的独特窗口。虽然目前的引力波实验更专注于低频状态，但在强磁场中引力子转化为光子构成了探测 HFGW 的有力工具。在本文中，我们表明，由于中子星具有极强的磁场，因此是研究 HFGW 转化为光子的完美实验室。使用银河系中子星群的真实模型，我们首次计算了银河系中中子星系群磁层中各向同性随机引力波背景转换所引起的预期光子通量。我们将该光子通量与从多台望远镜观测到的光子通量进行比较，并得出了频率范围为 108 Hz–1025 Hz 的随机引力波背景的上限。我们发现，在 108 Hz–1012 Hz 的频率范围内，我们的极限具有竞争力。