Gravitational-wave Limits from Pulsar Timing Constrain Supermassive Black Hole Evolution
R. M. Shannon, V. Ravi, W. A. Coles, G. Hobbs, M. J. Keith, R. N. Manchester, J. S. B. Wyithe, M. Bailes, N. D. R. Bhat, S. Burke-Spolaor, J. Khoo, Y. Levin, S.… 展开作者
R. M. Shannon, V. Ravi, W. A. Coles, G. Hobbs, M. J. Keith, R. N. Manchester, J. S. B. Wyithe, M. Bailes, N. D. R. Bhat, S. Burke-Spolaor, J. Khoo, Y. Levin, S. Osłowski, J. M. Sarkissian, W. van Straten, J. P. W. Verbiest, J-B. Wang
The formation and growth processes of supermassive black holes (SMBHs) are not well constrained. SMBH population models, however, provide specific predictions for the properties of the gravitational-wave background (GWB) from binary SMBHs in merging galaxies throughout the Universe. Using observations from the Parkes Pulsar Timing Array, we constrain the fractional GWB energy density with 95% confidence to be $Ω_{GW}(H_0/73 {\rm km} {\rm s}^{-1} {\rm Mpc}^{-1})^2 < 1.3 \times 10^{-9}$ at a frequency of 2.8 nHz, which is approximately a factor of six more stringent than previous limits. We compare our limit to models of the SMBH population and find inconsistencies at confidence levels between 46% and 91%. For example, the standard galaxy formation model implemented in the Millennium simulations is inconsistent with our limit with 50% probability.
Non-Gaussian timing residual skewness in pulsar timing arrays
Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Leibnitz Universität Hannover(马克斯·普朗克引力物理研究所(爱因斯坦研究所),莱布尼茨汉诺威大学);Department of Physics, National Central University(国立中央大学物理系);Institute of Physics, Academia Sinica(台湾中央研究院物理研究所);Institute of Astronomy and Astrophysics, Academia Sinica(台湾中央研究院天文及天文物理研究所)
Detecting Chiral Gravitational Wave Background with a Dipole Pulsar Timing Array
National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences(中国科学院大学杭州高等研究院);School of Astronomy and Space Science, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院);Institute of Fundamental Physics and Quantum Technology, Ningbo University(宁波大学基础物理与量子技术研究所);Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo(东京大学宇宙木理论研究所);Asia Pacific Center for Theoretical Physics(亚太理论物理中心);Leung Center for Cosmology and Particle Astrophysics, National Taiwan University(台湾大学梁氏宇宙学与粒子天体物理学研究中心);Yukawa Institute for Theoretical Physics, Kyoto University(京都大学汤川理论物理研究所)