Primordial black holes from Higgs inflation with a Gauss-Bonnet coupling
Primordial black holes from Higgs inflation with a Gauss-Bonnet coupling
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DOI：
10.1103/physrevd.107.063508
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发表时间：
2022-11
影响因子：
5
通讯作者：
R. Kawaguchi;S. Tsujikawa
中科院分区：
文献类型：
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作者：
R. Kawaguchi;S. Tsujikawa
原始黑洞（PBH）可能是今天所有或部分暗物质密度的来源。暴胀提供了一种机制，用于产生种子的PBH中存在的时间周期的暴胀场的速度$\phi$迅速减少到0。本文计算了在Gauss-Bonnet（GB）修正的Higgs暴胀过程中产生的曲率微扰的原初功率谱，其中暴胀子场不仅与引力有非最小耦合，而且还有GB耦合.对于一个标量-GB耦合在暴胀过程中表现出快速的变化，我们表明，曲率扰动充分增强的有效势$V_{\rmeff}（\phi）$的外观包含高原型，凹凸型，和它们的中间类型的结构。我们发现，对于这三种类型的V_{\rm eff}（\phi）$，存在着PBH可以构成所有暗物质的参数空间。特别是，凹凸和中间类型的模型产生的原始标量和张量功率谱与最近的普朗克数据尺度相关的宇宙微波背景观测相一致。这种特性归因于这样一个事实，即在$V_{\rm eff}（\phi）$的凸块区域周围获得的e-折叠$\Delta N_c$的数量可以小到几个，与其中$\Delta N_c$通常超过10的数量级的平台型形成对比。
Primordial black holes (PBHs) can be the source for all or a part of today's dark matter density. Inflation provides a mechanism for generating the seeds of PBHs in the presence of a temporal period where the velocity of an inflaton field $\phi$ rapidly decreases toward 0. We compute the primordial power spectra of curvature perturbations generated during Gauss-Bonnet (GB) corrected Higgs inflation in which the inflaton field has not only a nonminimal coupling to gravity but also a GB coupling. For a scalar-GB coupling exhibiting a rapid change during inflation, we show that curvature perturbations are sufficiently enhanced by the appearance of an effective potential $V_{\rm eff}(\phi)$ containing the structures of plateau-type, bump-type, and their intermediate type. We find that there are parameter spaces in which PBHs can constitute all dark matter for these three types of $V_{\rm eff}(\phi)$. In particular, models with bump- and intermediate-types give rise to the primordial scalar and tensor power spectra consistent with the recent Planck data on scales relevant to the observations of cosmic microwave background. This property is attributed to the fact that the number of e-foldings $\Delta N_c$ acquired around the bump region of $V_{\rm eff}(\phi)$ can be as small as a few, in contrast to the plateau-type where $\Delta N_c$ typically exceeds the order of 10.