Detection prospects for the GW background of Galactic (sub)solar mass primordial black holes

Abstract

In multi-component dark matter models, a fraction $f_{\text{pbh}}$ of the dark matter could be in the form of primordial black holes (PBHs) with (sub)solar masses. Some would have formed binaries that presently trace the Milky Way halo of particle dark matter. We explore the gravitational wave (GW) signal produced by such a hypothetical population of Galactic PBH binaries and assess its detectability by the LISA experiment. For this purpose, we model the formation and evolution of early-type PBH binaries accounting for GW hardening and binary disruption in the Milky Way. Our analysis reveals that the present-day Galactic population of PBH binaries is characterized by very high orbital eccentricities $|1-e|\ll 1$. For a PBH mass $M_{\mathrm{pbh}}\sim 0.1-1M_{\odot }$, this yields a GW background that peaks in the millihertz frequency range where the LISA instrumental noise is minimum. While this signal remains below the LISA detection threshold for viable $f_{\text{pbh}}\lesssim 0.01$, future GW observatories such as DECIGO and BBO could detect it if $0.01\lesssim M_{\mathrm{pbh}}\lesssim 0.1M_{\odot }$. Furthermore, we anticipate that, after 5 years of observations, LISA should be able to detect $\mathcal{O}(100)$ (resp. $\mathcal{O}(1)$) loud Galactic PBH binaries of mass $M_{\mathrm{pbh}}\sim 0.1-1M_{\odot }$ with a SNR $\ge 5$ if $f_{\mathrm{pbh}}=0.01$ (resp. $f_{\mathrm{pbh}}=0.001$). Nonlinear effects not considered here such as mass accretion and dynamical capture could alter these predictions.

44 pages, 17 figures, fixed typos and unclear phrasing

References in corpus (44)

• Primordial Black Holes as Dark Matter: Recent Developments
• The merger rate of primordial-black-hole binaries
• Effect of Primordial Black Holes on the Cosmic Microwave Background and Cosmological Parameter Estimates
• On the mass-to-light ratio of the local Galactic disc and the optical luminosity of the Galaxy
• Observational Evidence for Primordial Black Holes: A Positivist Perspective
• A brief review on primordial black holes as dark matter
• Inflation and Primordial Black Holes
• Solving puzzles of GW150914 by primordial black holes
• Complete waveform model for compact binaries on eccentric orbits
• The Effect of Orbital Eccentricity on Gravitational Wave Background Radiation from Supermassive Black Hole Binaries
• Observationally driven Galactic double white dwarf population for LISA
• No massive black holes in the Milky Way halo
• Search for subsolar-mass binaries in the first half of Advanced LIGO and Virgo's third observing run
• Constraining particle acceleration in Sgr A* with simultaneous GRAVITY, Spitzer, NuSTAR and Chandra observations
• LISA Sensitivity and SNR Calculations
• The effects of dynamical substructure on Milky Way mass estimates from the high velocity tail of the local stellar halo
• Spectral separation of the stochastic gravitational-wave background for LISA in the context of a modulated Galactic foreground
• Gravitational wave sources in our Galactic backyard: Predictions for BHBH, BHNS and NSNS binaries detectable with LISA
• Chaotic dynamics of wide triples induced by galactic tides: a novel channel for producing compact binaries, mergers, and collisions
• Constraints on primordial black holes from LIGO-Virgo-KAGRA O3 events
• A Rosetta Stone for eccentric gravitational waveform models
• The binary fraction, separation distribution, and merger rate of white dwarfs from SPY
• Gravitational Waves from Double White Dwarfs as probes of the Milky Way
• Close encounters of the primordial kind: a new observable for primordial black holes as dark matter
• The Population of Eccentric Binary Black Holes: Implications for mHz Gravitational Wave Experiments
• Rogue worlds meet the dark side: revealing terrestrial-mass primordial black holes with the Nancy Grace Roman Space Telescope
• Eccentricity dynamics of wide binaries -- I. The effect of Galactic tides
• Structure formation with primordial black holes: collisional dynamics, binaries, and gravitational waves
• GW230529_181500: A Potential Primordial Binary Black Hole Merger in the Mass Gap
• Binaries are softer than they seem: Effects of an external potential on the scattering dynamics of binaries
• Redshift evolution of primordial black hole merger rate
• Eccentricity effects on the supermassive black hole gravitational wave background
• Multi-messenger Probes of Asteroid Mass Primordial Black Holes: Superradiance Spectroscopy, Hawking Radiation, and Microlensing
• Subtraction of the confusion foreground and parameter uncertainty of resolvable galactic binaries on the networks of space-based gravitational-wave detectors
• Analysis of the subsolar-mass black hole candidate SSM200308 from the second part of the third observing run of Advanced LIGO-Virgo
• White dwarf binary modulation can help stochastic gravitational wave background search
• Lectures on Gravitational Wave Signatures of Primordial Black Holes
• Dancing with invisible partners: Three-body exchanges with primordial black holes
• Gravitational wave background from primordial black holes in globular clusters
• Frequency-Domain Distribution of Astrophysical Gravitational-Wave Backgrounds
• Observing dark matter clumps and asteroid-mass primordial black holes in the solar system with gravimeters and GNSS networks
• Projected gravitational wave constraints on primordial black hole abundance for extended mass distributions
• Gravitational waves from an eccentric population of primordial black holes orbiting Sgr A${}^{\star }$
• Lensing Constraints on PBHs: Substellar to Intermediate Masses

Cited by in corpus (1)

• Detection of the stochastic gravitational wave background with the space-borne gravitational-wave detector network