发表机构
University of Michigan（密歇根大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文计算热产生的大统一理论磁单极子丰度，并利用其能量密度及Parker和超级神冈实验约束，将宇宙再加热温度限制在GUT标度的0.35倍以下。
AI 中文摘要
磁单极子是大统一理论（GUT）的一个普遍预言，然而其存在与现代宇宙学和观测约束相矛盾。本文计算了早期宇宙中热产生的大统一理论单极子现今的丰度。我们通过考虑热丰度的完全相对论修正，以及由于辐射发射和与大质量规范玻色子、标准模型费米子及其超伴子散射而增强的单极子湮灭，改进了以往的计算。为了获得小于暗物质现今能量密度的单极子能量密度，我们表明，对于典型的't Hooft-Polyakov单极子质量，宇宙的再加热温度$T_{\rm RH}$必须小于大统一理论对称性破缺标度$T_{\rm GUT}$的0.55倍。考虑到现今磁单极子丰度的Parker界限，该约束被加强为$T_{\text{RH}}/T_{\text{GUT}} \lesssim 0.45$。此外，超级神冈实验的约束要求在我们的情景中$T_{\text{RH}}/T_{\text{GUT}} \lesssim 0.35$。
英文摘要
Magnetic monopoles are a generic prediction of Grand Unified Theories (GUTs) that are in tension with modern cosmological and observational bounds. In this paper, we calculate the present-day abundance of GUT monopoles produced thermally in the early Universe. We improve on previous calculations by accounting for full relativistic corrections to the thermal abundance and enhanced monopole annihilation due to the emission of radiation and scattering off massive gauge bosons, the Standard Model fermions and their superpartners. To obtain a present-day energy density less than that of dark matter, we show that the reheating temperature of the Universe, $T_{\rm RH}$, must be less than $0.55$ times the GUT symmetry breaking scale $T_{\rm GUT}$ for the canonical 't Hooft-Polyakov monopole mass. Accounting for Parker bounds on the present-day magnetic monopole abundance, the bound is tightened to $T_{\text{RH}}/T_{\text{GUT}} \lesssim 0.45$. Furthermore, experimental bounds from Super-Kamiokande require $T_{\text{RH}}/T_{\text{GUT}} \lesssim 0.35$ in our scenario.
Comments22 pages, 7 figures
