Detecting kHz gravitons from a neutron star merger with a multi-mode resonant mass detector
Instrumentation and Methods for Astrophysics2025-03-11v3Cosmology and Nongalactic AstrophysicsHigh Energy Astrophysical PhenomenaGeneral Relativity and Quantum CosmologyHigh Energy Physics - TheoryInstrumentation and DetectorsQuantum Physics
We propose a multi-mode bar consisting of mass elements of decreasing size for the implementation of a gravitational version of the photo-electric effect through the stimulated absorption of up to kHz gravitons from a binary neutron star merger and post-merger. We find that the multi-mode detector has normal modes that retain the coupling strength to the gravitational wave of the largest mass-element, while only having an effective mass comparable to the mass of the smallest element. This allows the normal modes to have graviton absorption rates due to the tonne-scale largest mass, while the single graviton absorption process in the normal mode could be resolved through energy measurements of a mass-element in-principle smaller than pico-gram scale. We argue the feasibility of directly counting gravito-phonons in the bar through energy measurements of the end mass. This improves the transduction of the single-graviton signal, enhancing the feasibility of detecting single gravitons.
@article{arxiv.2406.16898,
title = {Detecting kHz gravitons from a neutron star merger with a multi-mode resonant mass detector},
author = {Germain Tobar and Igor Pikovski and Michael Edmund Tobar},
journal= {arXiv preprint arXiv:2406.16898},
year = {2025}
}