Gravitational wave burst source direction estimation using time and amplitude information
Gravitational wave burst source direction estimation using time and amplitude information
复制标题
使用时间和幅度信息估计引力波爆发源方向
DOI：
10.1103/physrevd.78.122003
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发表时间：
2008
影响因子：
5
通讯作者：
E. Katsavounidis
中科院分区：
文献类型：
--
作者：
Jared Markowitz;M. Zanolin;L.Cadonati;E. Katsavounidis
在本文中，我们研究了使用干涉仪网络（IFO）的定时和幅度估计来评估入射引力波爆发的方向时出现的两个问题。首先，我们讨论基于最小二乘定时的方法中的角度偏差，该方法与中低信噪比变得越来越相关。我们展示了如何使用每个探测器的到达时间不确定性的估计来纠正这种偏差。我们还引入了一种独立的参数估计算法，该算法可以改进到达时间估计并提供每个站点的和方根应变幅度 (h{sub rss}) 值。在本文的第二部分中，我们讨论如何解决在真实源位置与其跨包含探测器的平面的镜像之间的三个非共处 IFO 中的观测所产生的方向模糊性。我们在三个站点的 h{sub rss} 值之间引入了一种新的精确关系，对于足够大的信号幅度，无论信号是否是线性偏振的，都可以确定真实的源方向。估计到达时间、到达时间不确定性和 h{sub rss} 值的算法以及定向跟踪都可以应用于在三个非共处 IFO 的网络中观察到的任何一组候选引力波。作为案例研究，我们在设计灵敏度下测试了 LIGO 和 Virgo 探测器噪声模拟中嵌入的模拟波形的方法。« less
In this article we study two problems that arise when using timing and amplitude estimates from a network of interferometers (IFOs) to evaluate the direction of an incident gravitational wave burst. First, we discuss an angular bias in the least squares timing-based approach that becomes increasingly relevant for moderate to low signal-to-noise ratios. We show how estimates of the arrival time uncertainties in each detector can be used to correct this bias. We also introduce a stand-alone parameter estimation algorithm that can improve the arrival time estimation and provide root-sum-squared strain amplitude (h{sub rss}) values for each site. In the second part of the paper we discuss how to resolve the directional ambiguity that arises from observations in three non co-located IFOs between the true source location and its mirror image across the plane containing the detectors. We introduce a new, exact relationship among the h{sub rss} values at the three sites that, for sufficiently large signal amplitudes, determines the true source direction regardless of whether or not the signal is linearly polarized. Both the algorithm estimating arrival times, arrival time uncertainties, and h{sub rss} values and the directional follow-up can be applied to any set of gravitational wave candidatesmore » observed in a network of three non co-located IFOs. As a case study we test the methods on simulated waveforms embedded in simulations of the noise of the LIGO and Virgo detectors at design sensitivity.« less