论文标题
引力波非线性和脉冲星阵列角相关性
Gravitational wave non-linearities and pulsar-timing array angular correlations
论文作者
论文摘要
几个脉冲星阵列（PTA）协作正在发现纳米赫兹式中随机重力波背景信号的诱人提示。不过，到目前为止，还没有发现预期的降期四极相关的令人信服的证据。尽管此问题可能是根据更准确，即将到来的数据来解决的，但保持关注不同的可能性并探索能够产生不同类型的PTA角相关性的情况很重要。我们指出，引力波背景的固定非高斯组件可以调节2点PTA重叠函数，从而增加了贡献，可以帮助拟合PTA数据的角度分布。我们讨论了这种非高斯信号的可能来源，就通货膨胀结束后发生的宇宙学过程而言，我们研究了这一想法的进一步测试。
Several pulsar-timing array (PTA) collaborations are finding tantalising hints for a stochastic gravitational wave background signal in the nano-Hertz regime. So far, though, no convincing evidence for the expected Hellings-Downs quadrupolar correlations has been found. While this issue might get fixed at the light of more accurate, forthcoming data, it is important to keep an eye open on different possibilities, and explore scenarios able to produce different types of PTA angular correlations. We point out that a stationary non-Gaussian component to the gravitational wave background can modulate the 2-point PTA overlap reduction function, adding contributions that can help in fitting the angular distribution of PTA data. We discuss possible sources for such non-Gaussian signal in terms of cosmological processes occurring after inflation ends, and we investigate further tests for this idea.
