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arXiv · 1908.11391

Unveiling the Gravitational Universe at \mu-Hz Frequencies

Abstract

We propose a space-based interferometer surveying the gravitational wave (GW) sky in the milli-Hz to $\mu$-Hz frequency range. By the 2040s', the $\mu$-Hz frequency band, bracketed in between the Laser Interferometer Space Antenna (LISA) and pulsar timing arrays, will constitute the largest gap in the coverage of the astrophysically relevant GW spectrum. Yet many outstanding questions related to astrophysics and cosmology are best answered by GW observations in this band. We show that a $\mu$-Hz GW detector will be a truly overarching observatory for the scientific community at large, greatly extending the potential of LISA. Conceived to detect massive black hole binaries from their early inspiral with high signal-to-noise ratio, and low-frequency stellar binaries in the Galaxy, this instrument will be a cornerstone for multimessenger astronomy from the solar neighbourhood to the high-redshift Universe.

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Alberto Sesana, Natalia Korsakova, Manuel Arca Sedda, Vishal Baibhav, Enrico Barausse, Simon Barke, Emanuele Berti, Matteo Bonetti, Pedro R. Capelo, Chiara Caprini, Juan Garcia-Bellido, Zoltan Haiman, Karan Jani, Oliver Jennrich, Peter Johansson, Fazeel Mahmood Khan, Valeriya Korol, Astrid Lamberts, Alessandro Lupi, Alberto Mangiagli, Lucio Mayer, Germano Nardini, Fabio Pacucci, Antoine Petiteau, Alvise Raccanelli, Surjeet Rajendran, John Regan, Lijing Shao, Alessandro Spallicci, Nicola Tamanini, Marta Volonteri, Niels Warburton, Kaze Wong, Miguel Zumalacarregui. 2019-08-29. Unveiling the Gravitational Universe at \mu-Hz Frequencies. https://doi.org/10.1007/s10686-021-09709-9

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