Whispers from the dark side: Confronting light new physics with NANOGrav data
Whispers from the dark side: Confronting light new physics with NANOGrav data
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DOI：
10.21468/scipostphys.10.2.047
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发表时间：
2020-09
期刊：
影响因子：
5.5
通讯作者：
Wolfram Ratzinger;P. Schwaller
中科院分区：
文献类型：
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作者：
Wolfram Ratzinger;P. Schwaller
NANOGrav的合作最近观察到了脉冲星计时数据中存在引力波背景(GWB)的第一个证据。在这里，我们探索了这种GWB是由于新物理的可能性，并表明该信号也可以很好地与峰值光谱相匹配，例如来自相变(PTS)或来自早期宇宙中类轴子粒子(Alps)的动力学的峰值光谱。我们发现，在1~MeV到10~MeV的温度范围内，对于非常强的PT，可以得到与数据很好的拟合。对于ALP的解释，得到了衰变常数F约为5×10^{17}F≈5×10 17~GeV和轴子质量2×10~(-13)2×10−~13 eV的最佳拟合。我们还说明了PTA约束这些模型的参数空间的能力，并获得了已经可以与其他宇宙学界限相比较的极限。
The NANOGrav collaboration has recently observed first evidence of a gravitational wave background (GWB) in pulsar timing data. Here we explore the possibility that this GWB is due to new physics, and show that the signal can be well fit also with peaked spectra like the ones expected from phase transitions (PTs) or from the dynamics of axion like particles (ALPs) in the early universe. We find that a good fit to the data is obtained for a very strong PT at temperatures around 1~MeV to 10~MeV. For the ALP explanation the best fit is obtained for a decay constant of F \approx 5\times 10^{17}F≈5×1017~GeV and an axion mass of 2\times 10^{-13}2×10−13~eV. We also illustrate the ability of PTAs to constrain the parameter space of these models, and obtain limits which are already comparable to other cosmological bounds.