How can LISA probe a population of GW190425-like binary neutron stars in the Milky Way?

Abstract

The nature of GW190425, a presumed binary neutron star (BNS) merger detected by the LIGO/Virgo Scientific Collaboration (LVC) with a total mass of $3.4_{-0.1}^{+0.3}$ M${}_{\odot }$, remains a mystery. With such a large total mass, GW190425 stands at five standard deviations away from the total mass distribution of Galactic BNSs of $2.66\pm 0.12$ M${}_{\odot }$. LVC suggested that this system could be a BNS formed from a fast-merging channel rendering its non-detection at radio wavelengths due to selection effects. BNSs with orbital periods less than a few hours - progenitors of LIGO/Virgo mergers - are prime target candidates for the future Laser Interferometer Space Antenna (LISA). If GW190425-like binaries exist in the Milky Way, LISA will detect them within the volume of our Galaxy and will measure their chirp masses to better than 10% for those binaries with gravitational wave frequencies larger than 2 mHz. This work explores how we can probe a population of Galactic GW190425-like BNSs with LISA and investigate their origin. We assume that the Milky Way's BNS population consists of two distinct sub-populations: a fraction $w_1$ that follows the observed Galactic BNS chirp mass distribution and $w_2$ that resembles chirp mass of GW190425. We show that LISA's accuracy on recovering the fraction of GW190425-like binaries depends on the BNS merger rate. For the merger rates reported in the literature, $21-212$Myr${}^{-1}$, the error on the recovered fractions varies between $\sim 30-5$%.

accepted by MNRAS

References in corpus (11)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Tests of general relativity from timing the double pulsar
• Formation of Double Neutron Star Systems
• The TianQin project: current progress on science and technology
• Science with the TianQin Observatory: Preliminary results on Galactic double white dwarf binaries
• PSR J1756$-$2251: a pulsar with a low-mass neutron star companion
• The Binary Companion of Young, Relativistic Pulsar J1906+0746
• Detecting Double Neutron Stars with LISA
• Simulating Neutron Star Mergers as r-process Sources in Ultra Faint Dwarf Galaxies
• Heavy double neutron stars: birth, mid-life and death
• How to detect the shortest-period binary pulsars in the era of LISA

Cited by in corpus (8)

• Observationally driven Galactic double white dwarf population for LISA
• Gravitational wave sources in our Galactic backyard: Predictions for BHBH, BHNS and NSNS binaries detectable with LISA
• Heavy double neutron stars: birth, mid-life and death
• Is the remnant of GW190425 a strange quark star?
• Astrophysics with the Laser Interferometer Space Antenna
• Discovering neutron stars with LISA via measurements of orbital eccentricity in Galactic binaries
• Gravitational wave energy spectral density properties from BPASS Galactic binary population in the Milky Way galaxy
• Probing the millisecond pulsar origin of the $\gamma$-ray excess in the Galactic centre with LISA