标题： 使用脉冲星测时阵列检验无滑移模型：NANOGrav 和 IPTA 显示英文标题

标题： Testing No slip model with pulsar timing arrays: NANOGrav and IPTA

摘要： 我们针对修正引力开展了一项观测研究，考虑了脉冲星计时阵列（PTA）的一种可能的暴胀解释。我们使用了一种被称为“无滑移”的模型，其中引力波传播被修改。具体来说，通过使用该模型的两种不同参数化方法，我们找到了张量扰动的近似传递函数。这样，我们得到了引力波的谱能量密度，并利用NANOGrav和IPTA第二数据发布来限制模型的参数。我们发现模型参数$\xi$和$c_M$存在退化现象。对于$c_M$，我们只得到了参数的一个上限。因此，目前的PTA数据很难以百分比级别的精度约束它们。 显示英文摘要

摘要： We perform an observational study of modified gravity considering a potential inflationary interpretation of pulsar timing arrays (PTA). We use a motivated model known as no slip in which the gravitational wave propagation is modified. Specifically, by using two different parametrizations for the model, we find the approximate transfer functions for tensor perturbations. In this way, we obtain the spectral energy density of gravitational waves and use NANOGrav and IPTA second data release to constrain parameters of the model. We find that there is degeneracy between the model parameters $\xi$ and $c_M$. For $c_M$, we only get an upper bound on the parameter. Thus, it is difficult to constrain them with percent level accuracy with the current PTA data.