Improving the sensitivity of future GW observatories in the 1–10 Hz band: Newtonian and seismic noise

The next generation gravitational wave interferometric detectors will likely be underground detectors to extend the GW detection frequency band to frequencies below the Newtonian noise limit. Newtonian noise originates from the continuous motion of the Earth’s crust driven by human activity, tidal stresses and seismic motion, and from mass density fluctuations in the atmosphere. It is calculated that on Earth’s surface, on a typical day, it will exceed the expected GW signals at frequencies below 10 Hz. The noise will decrease underground by an unknown amount. It is important to investigate and to quantify this expected reduction and its effect on the sensitivity of future detectors, to plan for further improvement strategies. We report M. G. Beker · M. Doets · E. Hennes · D. S. Rabeling · J. F. J. van den Brand · C. M. van Leeuwen Nikhef, National Institute for Subatomic Physics, P. O. Box 41182, 1009 DB Amsterdam, The Netherlands G. Cella (B) Istituto Nazionale di Fisica Nucleare sez. Pisa, Largo B. Pontecorvo 3, 56127 Pisa, Italy e-mail: [email protected] R. DeSalvo LIGO Laboratories, California Institute of Technology, Pasadena, CA 91125, USA H. Grote Max-Planck-Institute for Gravitational Research (Albert Einstein Institute), Hannover, Germany H. Grote Leibniz University Hannover, Hannover, Germany J. Harms · V. Mandic University of Minnesota, Minneapolis, MN 55455, USA D. S. Rabeling · J. F. J. van den Brand · C. M. van Leeuwen VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands