标题： 随机引力波背景的搜索模板 显示英文标题

标题： Search templates for stochastic gravitational-wave backgrounds

摘要： 多个基于地球的引力波（GW）探测器正在积极寻求对预测各种天体物理和宇宙源行为的模型施加观测限制。 这些源涵盖了广泛的范围，从中子星中的流体力学不稳定性（如r模）到早期宇宙中的粒子产生。 这些源中的一部分所发出的信号预计将在这些探测器中表现为随机引力波背景（SGWB）。 检测这些背景将有助于我们表征它们的来源。 考虑到这种背景也是某些探测器（如提议的空间探测器LISA）所需的，以便它们能够探测其他引力波信号。 在这里，我们提出了构建搜索模板库的问题，该模板库离散地覆盖了通用SGWB参数空间。 我们将其应用于一类被称为幂律模型的宇宙学SGWB的具体情况。 我们推导出模板密度在其三维参数空间中的变化，并表明对于具有LIGO-I灵敏度的LIGO 4公里探测器对，大约几百个模板就足以检测到这种背景，同时信噪比损失不超过3%。 显示英文摘要

摘要： Several earth-based gravitational-wave (GW) detectors are actively pursuing the quest for placing observational constraints on models that predict the behavior of a variety of astrophysical and cosmological sources. These sources span a wide gamut, ranging from hydrodynamic instabilities in neutron stars (such as r-modes) to particle production in the early universe. Signals from a subset of these sources are expected to appear in these detectors as stochastic GW backgrounds (SGWBs). The detection of these backgrounds will help us in characterizing their sources. Accounting for such a background will also be required by some detectors, such as the proposed space-based detector LISA, so that they can detect other GW signals. Here, we formulate the problem of constructing a bank of search templates that discretely span the parameter space of a generic SGWB. We apply it to the specific case of a class of cosmological SGWBs, known as the broken power-law models. We derive how the template density varies in their three-dimensional parameter space and show that for the LIGO 4km detector pair, with LIGO-I sensitivities, about a few hundred templates will suffice to detect such a background while incurring a loss in signal-to-noise ratio of no more than 3%.