镜像QCD相位过渡作为纳米赫兹静态重力波背景的起源
Lei Zu1, Chi Zhang2, Yao-Yu Li2
1Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210023, China.
Science bulletin
|February 6, 2024
概括
一项新的研究表明,暗量子色力学中的早期宇宙相位过渡可以解释检测到的纳米赫兹静态引力波背景 (SGWB),并解决宇宙学紧张局面.
科学领域:
- 宇宙学的宇宙学是什么?
- 粒子物理学 粒子物理学
- 天体物理学 天体物理学
背景情况:
- 脉冲星定时阵列 (PTA) 合作报告了纳米赫兹静态引力波背景 (SGWB) 的证据.
- 关于哈勃常数 (H0) 和物质聚类参数 (S8) 的测量存在宇宙学上的紧张关系.
研究的目的:
- 调查早期宇宙的暗量子染色力学 (QCD) 时代的第一阶段过渡.
- 探索镜子双胞胎希格斯黑暗部门模型作为SGWB的潜在来源.
- 确定这个模型是否可以同时解释SGWB并解决宇宙学紧张关系.
主要方法:
- 在镜子双子希格斯暗板模型中,对一阶相变的理论分析.
- 建模由此产生的随机引力波背景 (SGWB) 信号.
- 将预测的SGWB信号与PTA观测结果进行比较.
- 评估模型对H0和S8张力的影响.
主要成果:
- 从早期宇宙相位过渡中预测出一个可辨别的SGWB信号.
- 这个信号与当前的PTA测量结果一致.
- 一个显著的参数空间解决了SGWB观测和H0/S8张力.
- 镜子暗物质成分在0.2<ΔN<0.5.5.的总暗物质中不到30%.
结论:
- 镜子双子希格斯暗区模型中提出的相位过渡为纳米赫兹SGWB和宇宙参数张力提供了统一的解释.
- 这种情景提供了早期宇宙物理学和当前宇宙学观测之间的令人信服的联系.
- 未来的宇宙微波背景 (CMB) 实验,如CMB-S4,可以测试这个特定的参数区域.
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