论文标题
QCD相变的MHD湍流引力波作为PULSAR定时阵列的来源
Gravitational waves from MHD turbulence at the QCD phase transition as a source for Pulsar Timing Arrays
论文作者
论文摘要
We propose that the recent observations reported by the different Pulsar Timing Array (PTA) collaborations (i.e.~IPTA, EPTA, PPTA, and NANOGrav) of a common process over several pulsars could correspond to a stochastic gravitational wave background (SGWB) produced by turbulent sources in the early universe, in particular due to the magnetohydrodynamic (MHD) turbulence induced by primordial磁场。我讨论了MHD湍流数值模拟的最新结果，并提出了通过模拟验证的SGWB的分析模板。我们使用此模板使用PTA协作报告的结果来限制磁场参数。最后，我们比较了从PTA获得的原始磁场的约束与费米大面积望远镜（LAT）观察到的Blazar信号，超高能量宇宙射线的限制，以及宇宙微波背景。我们表明，在量子染色体动力学相变的尺度上产生的非螺旋原始磁场与这种约束兼容，并且可以在重组时提供磁场，这将有助于减轻哈勃张力。
We propose that the recent observations reported by the different Pulsar Timing Array (PTA) collaborations (i.e.~IPTA, EPTA, PPTA, and NANOGrav) of a common process over several pulsars could correspond to a stochastic gravitational wave background (SGWB) produced by turbulent sources in the early universe, in particular due to the magnetohydrodynamic (MHD) turbulence induced by primordial magnetic fields. I discuss recent results of numerical simulations of MHD turbulence and present an analytical template of the SGWB validated by the simulations. We use this template to constrain the magnetic field parameters using the results reported by the PTA collaborations. Finally, we compare the constraints on the primordial magnetic fields obtained from PTA with those from blazar signals observed by Fermi Large Area Telescope (LAT), from ultra high-energy cosmic rays, and from the cosmic microwave background. We show that a non-helical primordial magnetic field produced at the scale of the quantum chromodynamics phase transition is compatible with such constraints and it could additionally provide with a magnetic field at recombination that would help to alleviate the Hubble tension.
