论文标题
引力波背景的重叠函数的完整分析表达与脉冲星时阵列
Full analytic expression of overlap reduction function for gravitational wave background with pulsar timing arrays
论文作者
论文摘要
Pulsar定时阵列（PTA）有望在未来十年内检测纳米赫茨带中的重力波背景（GWB）。这提供了测试重力理论和宇宙学的机会。检测GWB的典型数据分析方法是互相关分析。重叠函数（ORF）在GWB的相关数据分析中起重要作用。当前处理ORF中复杂集成的方法是使用短波近似来删除棘手的术语。在本文中，我们为PTA提供了ORF的完整分析表达，而无需任何近似值，所有可能的极性通过一般相对性的修改允许。与数值模拟和短波近似相比，我们的结果更有效且广泛适用。尤其是对于不可用短波近似的标量延伸模式，我们的分析表达特别重要。
Pulsar timing array (PTA) is expected to detect gravitational wave background (GWB) in the nanohertz band within the next decade. This provides an opportunity to test the gravity theory and cosmology. A typical data analysis method to detect GWB is cross-correlation analysis. The overlap reduction function (ORF) plays an important role in the correlation data analysis of GWB. The present approach to dealing with the intricate integration in ORF is to use short-wave approximation to drop out the tricky terms. In this paper, we provide the full analytic expression of the ORF for PTA without any approximation for all possible polarizations allowed by modifications of general relativity. Compared with the numerical simulation and short-wave approximation, our results are more efficient and widely applicable. Especially for the scalar-longitudinal mode where the short-wave approximation is not available, our analytical expression is particularly significant.
