Gravitational Wave Constraints on Planetary-Mass Primordial Black Holes Using LIGO O3a Data
Year: 2024
Type: article
Abstract: Gravitational waves from subsolar mass inspiraling compact objects would provide almost smoking-gun evidence for primordial black holes (PBHs). We perform the first search for inspiraling planetary-mass compact objects in equal-mass and highly asymmetric mass-ratio binaries using data from the first half of the LIGO-Virgo-KAGRA third observing run. Though we do not find any significant candidates, we determine the maximum luminosity distance reachable with our search to be of $\mathcal{O}(0.1--100)\text{ }\text{ }\mathrm{kpc}$, and corresponding model-independent upper limits on the merger rate densities to be $\mathcal{O}({10}^{3}--{10}^{\ensuremath{-}7})\text{ }\text{ }{\mathrm{kpc}}^{\ensuremath{-}3}\text{ }{\mathrm{yr}}^{\ensuremath{-}1}$ for systems with chirp masses of $\mathcal{O}({10}^{\ensuremath{-}4}--{10}^{\ensuremath{-}2}){M}_{\ensuremath{\bigodot}}$, respectively. Furthermore, we interpret these rate densities as arising from PBH binaries and constrain the fraction of dark matter that such objects could comprise. For equal-mass PBH binaries, we find that these objects would compose less than 4%--100% of DM for PBH masses of ${10}^{\ensuremath{-}2}{M}_{\ensuremath{\bigodot}}$ to $2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}{M}_{\ensuremath{\bigodot}}$, respectively. For asymmetric binaries, assuming one black hole mass corresponds to a peak in the mass function at $2.5{M}_{\ensuremath{\bigodot}}$, a PBH dark-matter fraction of 10% and a second, much lighter PBH, we constrain the mass function of the second PBH to be less than 1 for masses between $1.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}{M}_{\ensuremath{\bigodot}}$ and $2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}{M}_{\ensuremath{\bigodot}}$. Our constraints, recently released, are robust enough to be applied to any PBH or exotic compact object binary formation models, and complement existence microlensing results.
Source: Physical Review Letters
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, European Commission, Fonds De La Recherche Scientifique - FNRS, Max-Planck-Gesellschaft, Centre National de la Recherche Scientifique, Science and Technology Facilities Council, Australian Research Council, Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture, Instituto Nazionale di Fisica Nucleare
OpenAlex ID: W4402407600