We report the first search results for axion dark matter using an 18 T high-temperature superconducting magnet haloscope. The scan frequency ranges from 4.7789 to 4.8094 GHz. No significant signal consistent with the Galactic halo dark matter axion is observed. The results set the best upper bound of axion-photon-photon coupling ($g_{a\gamma \gamma }$) in the mass ranges of 19.764 to $19.771\mu \mathrm{eV}$ (19.863 to $19.890\mu \mathrm{eV}$) at $1.5\times |g_{a\gamma \gamma }^{\mathrm{KSVZ}}|$ ($1.7\times |g_{a\gamma \gamma }^{\mathrm{KSVZ}}|$), and 19.772 to $19.863\mu \mathrm{eV}$ at $2.7\times |g_{a\gamma \gamma }^{\mathrm{KSVZ}}|$ with 90% confidence level, respectively. This remarkable sensitivity in the high mass region of dark matter axion is achieved by using the strongest magnetic field among the existing haloscope experiments and realizing a low-noise amplification of microwave signals using a Josephson parametric converter.

中文翻译：

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用 18 T 磁光环寻找不可见的轴子暗物质

我们使用 18 T 高温超导磁体光环报告了轴子暗物质的首次搜索结果。扫描频率范围为 4.7789 至 4.8094 GHz。没有观察到与银河晕暗物质轴子一致的显着信号。结果设定了轴子 - 光子 - 光子耦合的最佳上限（$G_{\mathrm{一个}\gamma \gamma }$) 的质量范围为 19.764 至$19.771\mu \mathrm{电子伏特}$（19.863 至$19.890\mu \mathrm{电子伏特}$） 在$1.5\times |G_{\mathrm{一个}\gamma \gamma }^{\mathrm{KSVZ}}|$($1.7\times |G_{\mathrm{一个}\gamma \gamma }^{\mathrm{KSVZ}}|$) 和 19.772 到$19.863\mu \mathrm{电子伏特}$在$2.7\times |G_{\mathrm{一个}\gamma \gamma }^{\mathrm{KSVZ}}|$分别具有 90% 的置信水平。这种在暗物质轴子高质量区域的显着灵敏度是通过使用现有光环实验中最强的磁场并使用约瑟夫森参数转换器实现微波信号的低噪声放大来实现的。