论文标题
低质量衰减颗粒对光子注入的光谱失真约束
Spectral distortion constraints on photon injection from low-mass decaying particles
论文作者
论文摘要
宇宙微波背景（CMB）的光谱失真（SDS）为研究粒子物理学提供了有力的工具。在这里，我们计算腐烂粒子的失真信号，这些粒子在宇宙历史期间直接转化为不同时期的光子，重点关注注入能量$ e_ \ mathrm {inj} \ sillesim 20 \，\ mathrm {kev} $。我们提供了全面的SD解决方案库，可用于研究各种粒子物理方案。我们使用{\ tt cosmotherm}来计算SD信号，包括对宇宙电离历史记录和不透明度的影响。我们还考虑了黑体引起的刺激衰减的效果，这可以显着修改注射史。然后，我们使用来自Cobe/Firas和边缘的数据来限制衰减颗粒的性质。我们探索这些场景，其中这些场景提供了暗物质（DM）候选或仅构成DM的一小部分。我们将SD约束与CMB各向异性约束相辅相成，突出了在非常低的光子能量（$Hν\ Lessim 10^{ - 4} \，\ Mathrm {ev ev} $）的注射中的新效果。我们的模型无关的约束在生命周期内表现出丰富的结构，涵盖了注入能量$ e_ \ mathrm {inj} \ simeq 10^{ - 10} \ 10} \ Mathrm {ev} -10 \ 10 -10 \ \ m mathrm 10^5 \，\ Mathrm {S} -10^{33} \ Mathrm {S} $。我们讨论了直接转化为两个光子的轴和类似轴的粒子的约束，从而修改了文献中现有的SD约束。我们的限制与轴质量的其他约束$ m_a c^2 \ gtrsim 27 \，\ mathrm {ev} $具有竞争力，我们发现基于整体能量学的简单估计通常不准确。未来的CMB光谱仪可以显着改善所获得的限制，从而提供了早期宇宙粒子物理的重要互补探针。
Spectral distortions (SDs) of the cosmic microwave background (CMB) provide a powerful tool for studying particle physics. Here we compute the distortion signals from decaying particles that convert directly into photons at different epochs during cosmic history, focusing on injection energies $E_\mathrm{inj}\lesssim 20\,\mathrm{keV}$. We deliver a comprehensive library of SD solutions that can be used to study a wide range of particle physics scenarios. We use {\tt CosmoTherm} to compute the SD signals, including effects on the ionization history and opacities of the Universe. We also consider the effect of blackbody-induced stimulated decay, which can modify the injection history significantly. Then, we use data from COBE/FIRAS and EDGES to constrain the properties of the decaying particles. We explore scenarios where these provide a dark matter (DM) candidate or constitute only a small fraction of DM. We complement the SD constraints with CMB anisotropy constraints, highlighting new effects from injections at very-low photon energies ($hν\lesssim 10^{-4}\,\mathrm{eV}$). Our model-independent constraints exhibit rich structures in the lifetime-energy domain, covering injection energies $E_\mathrm{inj}\simeq 10^{-10}\mathrm{eV}-10\mathrm{keV}$ and lifetimes $τ_X\simeq 10^5\,\mathrm{s}-10^{33}\mathrm{s}$. We discuss the constraints on axions and axion-like particles that convert directly into two photons, revising existing SD constraints in the literature. Our limits are competitive with other constraints for axion masses $m_a c^2\gtrsim 27\,\mathrm{eV}$ and we find that simple estimates based on the overall energetics are generally inaccurate. Future CMB spectrometers could significantly improve the obtained constraints, thus providing an important complementary probe of early-universe particle physics.
