Bayesian characterization of circumbinary sub-stellar objects with LISA

DOI: 
10.1093/mnras/stac2555
Publication date: 
08/11/2022
Main author: 
Katz, Michael L.
IAA authors: 
Danielski, Camilla
Authors: 
Katz, Michael L.;Danielski, Camilla;Karnesis, Nikolaos;Korol, Valeriya;Tamanini, Nicola;Cornish, Neil J.;Littenberg, Tyson B.
Journal: 
Monthly Notices of the Royal Astronomical Society
Publication type: 
Article
Volume: 
517
Pages: 
697-711
Abstract: 
The Laser Interferometer Space Antenna (LISA) will detect and characterize ~10<SUP>4</SUP> Galactic Binaries, consisting predominantly of two white dwarfs (WDs). An interesting prospect within this population is a third object - another WD star, a circumbinary exoplanet (CBP), or a brown dwarf (BD) - in orbit about the inner WD pair. We present the first fully Bayesian detection and posterior analysis of substellar objects with LISA, focusing on the characterization of CBPs. We used an optimistic astrophysically motivated catalogue of these CBP third-body sources, including their orbital eccentricity around the inner binary for the first time. We examined Bayesian evidence computations for detectability, as well as the effects on the posterior distributions for both the inner binary parameters and the third-body parameters. We find that the posterior behaviour bifurcates based on whether the third-body period is above or below half the observation time. Additionally, we find that undetectable third-body sources can bias the inner binary parameters whether or not the correct template is used. We used the information retrieved from the study of the CBP population to make an initial conservative prediction for the number of detectable BD systems in the original catalogue. We end with commentary on the predicted qualitative effects on LISA global fitting and Galactic Binary population analysis. The procedure used in this work is generic and can be directly applied to other astrophysical effects expected within the Galactic Binary population.
Database: 
ADS
SCOPUS
URL: 
https://ui.adsabs.harvard.edu/#abs/2022MNRAS.517..697K/abstract
ADS Bibcode: 
2022MNRAS.517..697K
Keywords: 
gravitational waves;white dwarfs;planets and satellites: detection;Astrophysics - Earth and Planetary Astrophysics;Astrophysics - Instrumentation and Methods for Astrophysics;Astrophysics - Solar and Stellar Astrophysics;General Relativity and Quantum Cosmology