NANOGrav 11年数据集：脉冲星计时对随机引力波背景的约束
高能天体物理现象
2018-06-11 v2 星系天体物理
广义相对论与量子宇宙学
摘要
我们在北美纳赫兹引力波天文台(NANOGrav)新发布的年数据集中搜寻各向同性随机引力波背景(GWB)。虽然我们未发现GWB的显著证据，但我们对来自超大质量黑洞双星种群、宇宙弦以及原初GWB的GWB给出了约束。我们首次发现GWB的上限与探测统计量对所采用的太阳系星历(SSE)模型敏感，且SSE误差可模仿GWB信号。我们开发了一种弥合系统性SSE差异的方法，产生了首个对SSE不确定性稳健的PTA约束。因此，对于基准幂律谱且建模了脉冲星间相关，我们在频率 yr处对GW应变振幅给出上限，这比采用相同流程计算的NANOGrav 年极限改善了约倍。鉴于SSE系统性不确定性，先前PTA对GWB的上限需作修订。我们利用约束刻画了星系核中恒星质量密度、SMBH双星偏心率以及SMBH—星系核球标度关系对GWB的综合影响。我们利用近期模拟约束宇宙弦张力，得出SSE边缘化后的宇宙弦张力上限——比已发表的NANOGrav 年约束改善约倍。我们对原初GWB(针对暴胀后辐射主导宇宙)能量密度的SSE边缘化上限为。
引用
@article{arxiv.1801.02617,
title = {The NANOGrav 11-year Data Set: Pulsar-timing Constraints On The Stochastic Gravitational-wave Background},
author = {Z. Arzoumanian and P. T. Baker and A. Brazier and S. Burke-Spolaor and S. J. Chamberlin and S. Chatterjee and B. Christy and J. M. Cordes and N. J. Cornish and F. Crawford and H. Thankful Cromartie and K. Crowter and M. DeCesar and P. B. Demorest and T. Dolch and J. A. Ellis and R. D. Ferdman and E. Ferrara and W. M. Folkner and E. Fonseca and N. Garver-Daniels and P. A. Gentile and R. Haas and J. S. Hazboun and E. A. Huerta and K. Islo and G. Jones and M. L. Jones and D. L. Kaplan and V. M. Kaspi and M. T. Lam and T. J. W. Lazio and L. Levin and A. N. Lommen and D. R. Lorimer and J. Luo and R. S. Lynch and D. R. Madison and M. A. McLaughlin and S. T. McWilliams and C. M. F. Mingarelli and C. Ng and D. J. Nice and R. S. Park and T. T. Pennucci and N. S. Pol and S. M. Ransom and P. S. Ray and A. Rasskazov and X. Siemens and J. Simon and R. Spiewak and I. H. Stairs and D. R. Stinebring and K. Stovall and J. Swiggum and S. R. Taylor and M. Vallisneri and S. Vigeland and W. W. Zhu},
journal= {arXiv preprint arXiv:1801.02617},
year = {2018}
}
备注
21 pages, 12 figures, 9 tables. Published in The Astrophysical Journal. Please send any comments/questions to S. R. Taylor ([email protected])