A new detector, the Fermilab Holometer, consists of separate yet identical 39-meter Michelson interferometers. Strain sensitivity achieved is better than 10−21/Hz between 1 to 13 MHz from a 130-hr dataset. This measurement exceeds the sensitivity and frequency range made from previous high frequency gravitational wave experiments by many orders of magnitude. Constraints are placed on a stochastic background at 382 Hz resolution. The 3σ upper limit on ΩGW, the gravitational wave energy density normalized to the closure density, ranges from 5.6×1012 at 1 MHz to 8.4×1015 at 13 MHz. Another result from the same dataset is a search for nearby primordial black hole binaries (PBHB). There are no detectable monochromatic PBHBs in the mass range 0.83 - 3.5×1021g between the earth and the moon. Projections for a chirp search with the same dataset increases the mass range to 0.59−2.5×1025g and distances out to Jupiter. This result presents a new method for placing limits on a poorly constrained mass range of primordial black holes. Additionally, solar system searches for PBHBs place limits on their contribution to the total dark matter fraction.
@article{arxiv.1611.05560,
title = {MHz Gravitational Wave Constraints with Decameter Michelson Interferometers},
author = {Aaron S. Chou and Richard Gustafson and Craig Hogan and Brittany Kamai and Ohkyung Kwon and Robert Lanza and Shane L. Larson and Lee McCuller and Stephan S. Meyer and Jonathan Richardson and Chris Stoughton and Raymond Tomlin and Rainer Weiss},
journal= {arXiv preprint arXiv:1611.05560},
year = {2017}
}