超冷的相位过渡能解释脉冲星计时阵列所观察到的引力波背景吗?
Peter Athron1, Andrew Fowlie2, Chih-Ting Lu1
1Department of Physics and Institute of Theoretical Physics, Nanjing Normal University, Nanjing 210023, China.
Physical review letters
|June 15, 2024
概括
从超冷却相位过渡中在nHz频率创建一个随机引力波背景 (SGWB) 信号是具有挑战性的. 两个关键问题,不完整的过渡和重新加热温度,使SGWB与新物理学的连接复杂化.
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:
- 脉冲星计时阵列已经检测到在nHz频率的静态引力波背景 (SGWB) 的证据.
- 这种SGWB可能源于超大质量黑洞的合并,或者是100 MeV尺度附近的新物理信号.
- 超冷却的第一阶段过渡 (FOPT) 结束于100 MeV是将SGWB与电弱尺度物理联系起来的解释.
研究的目的:
- 调查从超冷却的第一阶段过渡中生成nHz SGWB信号的可行性.
- 确定可能排除对观测到的SGWB提出的超冷解释的关键挑战.
- 分析基于非线性实现的电弱对称性的特定模型作为案例研究.
主要方法:
- 超冷的第一阶段过渡的理论分析.
- 检查气泡透和过渡完成动态.
- 在相位过渡后重新加热温度的研究.
主要成果:
- 一个第一阶段过渡不能在所需的100 MeV过渡温度下完成,因为长时间的真空支配阻碍了泡透.
- 即使实现过渡完成或绕过过渡,宇宙通常会重新升温到驱动过渡的物理的能量尺度.
- 过渡温度和再加热温度之间的显著层次结构使SGWB频谱的计算变得复杂.
结论:
- 从超冷的相位过渡生成一个nHz的SGWB信号比以前假设的要复杂得多.
- 对于许多拟议的超冷FOPT模型来说,不完整的过渡和重新加热层次结构的确定的问题构成了重大障碍.
- 需要进一步的理论和观察性审查来使nHz SGWB与通过超冷却相位过渡的新物理相协调.
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