论文标题
来自轴向黑暗光子系统的重力波：晶格研究
Gravitational Waves from an Axion-Dark Photon System: A Lattice Study
论文作者
论文摘要
在这项工作中，我们介绍了早期宇宙中轴轴 - 暗光子系统的晶格研究，并表明该系统产生的随机重力波（GW）背景可以通过在广泛频率的未来GW实验进行探测。晶格上的数值模拟使我们能够考虑非线性的反应效应，并使我们能够准确预测轴法或轴突样粒子（ALP）及其不均匀性的最终遗物丰度，并提供了GW Spectrum的更精确预测。重要的是，我们发现，由于$ 2 \ rightarrow1 $流程，GW频谱在高电平方面具有更大的功率。此外，我们发现GW频谱峰的极化程度取决于ALP-Dark光子偶联，并且可以将极化洗净甚至可以以其大值洗涤。与文献中的最新结果一致，我们发现ALP遗物丰度可以被两个数量级抑制，并讨论扩展可行参数空间的模型的可能扩展。最后，我们讨论了通过CMB的光谱扭曲探测超轻ALP暗物质的可能性。
In this work, we present a lattice study of an axion - dark photon system in the early Universe and show that the stochastic gravitational wave (GW) background produced by this system may be probed by future GW experiments across a vast range of frequencies. The numerical simulation on the lattice allows us to take into account non-linear backreaction effects and enables us to accurately predict the final relic abundance of the axion or axion-like particle (ALP) as well as its inhomogeneities, and gives a more precise prediction of the GW spectrum. Importantly, we find that the GW spectrum has more power at high momenta due to $2\rightarrow1$ processes. Furthermore, we find the degree of polarization of the peak of the GW spectrum depends on the ALP-dark photon coupling and that the polarization can be washed out or even flipped for large values thereof. In line with recent results in the literature, we find the ALP relic abundance may be suppressed by two orders of magnitude and discuss possible extensions of the model that expand the viable parameter space. Finally, we discuss the possibility to probe ultralight ALP dark matter via spectral distortions of the CMB.
