LIGO-California Institute of Technology, Pasadena, California 91125, USA.
Louisiana State University, Baton Rouge, Louisiana 70803, USA.
Phys Rev Lett. 2014 Apr 4;112(13):131101. doi: 10.1103/PhysRevLett.112.131101.
Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension Gμ below 10(-8) in some regions of the cosmic string parameter space.
宇宙弦可以产生各种各样有趣的天体物理现象。其中，由宇宙弦的尖点产生的强大的引力波（GW）爆发是一个很有前途的观测特征。在这封信中，我们在 LIGO 和 Virgo 引力波探测器在 2005 年至 2010 年间收集的数据中进行了搜索，这些数据的实时时间超过了 625 天。我们没有发现来自宇宙弦尖点的 GW 信号的证据。根据这一结果，我们对宇宙弦参数进行了新的限制，这补充并改进了之前从宇宙微波背景测量和脉冲星定时数据中搜索宇宙背景 GW 得到的现有限制。特别是，如果环的大小由引力反作用尺度给出，那么在宇宙弦参数空间的某些区域，我们对弦张力 Gμ 的上限低于 10（-8）。
