Investigation of quasibound states of black holes is significant for expected ultralight particles, as well as black holes through gravitational waves. We first investigate quasibound states of a massive scalar field for dilatonic charged black holes via numerical analysis. We study the complex eigenfrequencies of the massive scalar field in a wide range of gravitational fine structure constant $\mu M$ in detail, and show the effects of charge. Further, we study the eigenfrequencies of the massive field through an analytical approach by matching the near horizon solution and far field solution, and find its spectra for excited states by the iteration method. We demonstrate that the numerical solution and analytical solution perfectly agree with each other in the region where charge of the black hole is large, both for real and imaginary parts of the eigenfrequencies.

中文翻译：

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带电膨胀的黑洞的拟束缚态

对于预期的超轻粒子以及通过引力波产生的黑洞，研究黑洞的准结合态具有重要意义。我们首先通过数值分析研究了带膨胀带电黑洞的大标量场的准束缚状态。我们研究了在广泛的引力精细结构常数范围内大标量场的复本征频率$\mu \mathrm{中号}$详细说明充电效果。此外，我们通过匹配近视层解和远场解的分析方法研究了大场的本征频率，并通过迭代方法找到了其激发态的光谱。我们证明，对于本征频率的实部和虚部，在黑洞电荷大的区域中，数值解和解析解彼此完全吻合。