Abstract
Neutron star–white dwarf (NS + WD) binaries offer a unique opportunity for studying NS-specific phenomena with gravitational waves. In this paper, we employ the binary population synthesis technique to study the Galactic population of NS + WD binaries with the future Laser Interferometer Space Antenna (LISA). We anticipate approximately
detectable NS + WD binaries by LISA, encompassing both circular and eccentric ones formed via different pathways. Despite the challenge of distinguishing these binaries from more prevalent double white dwarfs (especially at frequencies below 2 mHz), we show that their eccentricity and chirp mass distributions may provide avenues to explore the NS natal kicks and common envelope evolution. Additionally, we investigate the spatial distribution of detectable NS + WD binaries relative to the Galactic plane and discuss prospects for identifying electromagnetic counterparts at radio wavelengths. Our results emphasise LISA’s capability to detect and characterize NS + WD binaries and to offer insights into the properties of the underlying population. Our conclusions carry significant implications for shaping LISA data analysis strategies and future data interpretation.
detectable NS + WD binaries by LISA, encompassing both circular and eccentric ones formed via different pathways. Despite the challenge of distinguishing these binaries from more prevalent double white dwarfs (especially at frequencies below 2 mHz), we show that their eccentricity and chirp mass distributions may provide avenues to explore the NS natal kicks and common envelope evolution. Additionally, we investigate the spatial distribution of detectable NS + WD binaries relative to the Galactic plane and discuss prospects for identifying electromagnetic counterparts at radio wavelengths. Our results emphasise LISA’s capability to detect and characterize NS + WD binaries and to offer insights into the properties of the underlying population. Our conclusions carry significant implications for shaping LISA data analysis strategies and future data interpretation.
| Original language | English |
|---|---|
| Pages (from-to) | 844-860 |
| Journal | Monthly Notices of the Royal Astronomical Society |
| Volume | 530 |
| Issue number | 1 |
| Early online date | 27 Mar 2024 |
| DOIs | |
| Publication status | Published - 1 May 2024 |
Bibliographical note
ACKNOWLEDGEMENTSWe are grateful to the referee for their careful reading of the manuscript and insightful comments. We also thank the LISA Birmingham group, particularly Hannah Middleton, Riccardo Buscicchio, Diganta Bandopadhyay, and Alberto Vecchio, for their fruitful discussions during group meetings. We also wish to acknowledge that preliminary work on this topic began with Ms Abbie Nicholls’ MSc thesis, a (2019/2020) Physics graduate from the University of Birmingham.
VK and ST acknowledge support from the Netherlands Research Council NWO (respectively, Rubicon 019.183EN.015, and VENI 639.041.645, VIDI 203.061 grants). Work of API is supported by STFC grant no. ST/W000873/1.
This research made use of the tools provided by the LISA Data Processing Group (LDPG) and the LISA Consortium LISA Data Challenges (LDC) working group.2
This research made use of ASTROPY,3 a community-developed core PYTHON package for Astronomy (Astropy Collaboration et al. 2013, 2018), MATPLOTLIB (Hunter 2007), NUMPY (Oliphant 2006; Van der Walt, Colbert & Varoquaux 2011), SCIPY (Virtanen et al. 2020), GALPY4 (Bovy 2015), and JOYPY5 packages.
Keywords
- gravitational waves
- binaries: close
- stars: neutron
- stars: white dwarf