Ultra-light bosons such as axions or axion-like particles (ALPs), are promising candidates to solve the dark matter problem. A unique way to detect such ALPs is to search for the periodic oscillation feature of the position angles of linearly polarized photons emitted from the galaxy center. In this work, we use the high-resolution polarimetric measurements of the radiation near the super-massive black hole (SMBH) in the center of the Milky Way, i.e., Sagittarius A^⋆ (Sgr A^⋆), by a sub-array of the Event Horizon Telescope to search for the ultra-light ALPs. We derive upper limits on the ALP-photon coupling of ∼ 10^-12 GeV^-1 for ALP masses of m_a∼ (10^-19-10^-18) eV, with a solitonic core + NFW dark matter density profile. Our results are stronger than that derived from the observations of SN1987A and a population of supernovae in the mass window of (10^-19-10^-17)eV. Improved polarimetric measurements with the full Event Horizon Telescope can further strengthen theconstraints.

超轻的玻色子，例如斧子或类似斧子的粒子（ALP），有望解决暗物质问题。检测此类ALP的一种独特方法是搜索从银河中心发射的线性偏振光子的位置角的周期性振荡特征。在这项工作中，我们使用银河系的子阵列对银河系中心超大质量黑洞（SMBH）附近的辐射（即人马座^A⋆（Sgr ^A⋆））进行高分辨率偏振测量。使用Event Horizo​​n望远镜搜索超轻型ALP。我们推导上〜10的ALP光子耦合上限^-12 GeV的^-1对于m的ALP群众_一个〜（10 ^-19 -10 ^-18）eV，具有孤子芯+ NFW暗物质密度分布图。我们的结果比从SN1987A的观测结果和在（10 ^-19 -10 ^-17）eV的质量窗口中的超新星种群所得出的结果要强。使用完整的事件地平线望远镜改进的偏振测量可以进一步加强约束条件。