Prospects for Detecting Gravitational Waves at 5 Hz with Ground-Based Detectors

• Main Authors: Barr, Bryan (Author), Hammond, Giles (Author), Hild, Stefan (Author), Hough, James (Author), Huttner, Sabina (Author), Rowan, Sheila (Author), Sorazu, Borja (Author), Carbone, Ludovico (Author), Freise, Andreas (Author), Mow-Lowry, Conor (Author), Dooley, Katherine L. (Author), Fulda, Paul (Author), Grote, Hartmut (Author), Sigg, Daniel (Author), Yu, Hang (Contributor), Martynov, Denis (Contributor), Vitale, Salvatore (Contributor), Evans, Matthew J (Contributor), Shoemaker, David H (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Physics (Contributor), LIGO (Observatory : Massachusetts Institute of Technology) (Contributor), MIT Kavli Institute for Astrophysics and Space Research (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2018-04-09T18:22:38Z.
• Subjects: Article
• Online Access: Get fulltext

We propose an upgrade to Advanced LIGO (aLIGO), named LIGO-LF, that focuses on improving the sensitivity in the 5-30 Hz low-frequency band, and we explore the upgrade's astrophysical applications. We present a comprehensive study of the detector's technical noises and show that with technologies currently under development, such as interferometrically sensed seismometers and balanced-homodyne readout, LIGO-LF can reach the fundamental limits set by quantum and thermal noises down to 5 Hz. These technologies are also directly applicable to the future generation of detectors. We go on to consider this upgrade's implications for the astrophysical output of an aLIGO-like detector. A single LIGO-LF can detect mergers of stellar-mass black holes (BHs) out to a redshift of z≃6 and would be sensitive to intermediate-mass black holes up to 2000  M_{⊙}. The detection rate of merging BHs will increase by a factor of 18 compared to aLIGO. Additionally, for a given source the chirp mass and total mass can be constrained 2 times better than aLIGO and the effective spin 3-5 times better than aLIGO. Furthermore, LIGO-LF enables the localization of coalescing binary neutron stars with an uncertainty solid angle 10 times smaller than that of aLIGO at 30 Hz and 4 times smaller when the entire signal is used. LIGO-LF also significantly enhances the probability of detecting other astrophysical phenomena including the tidal excitation of neutron star r modes and the gravitational memory effects.
United States. National Aeronautics and Space Administration (Grant NNX14AB40G)