Determining gravitational wave radiation from close galaxy pairs using a binary population synthesis approach

TL;DR

This paper proposes a new method to detect gravitational waves from supermassive black hole binaries in close galaxy pairs using a binary population synthesis approach, with potential detection by future radio observatories.

Contribution

It introduces a novel approach combining SDSS data and population synthesis to estimate gravitational wave signals from SMBH binaries for upcoming detectors.

Findings

Strain amplitude varies from 10^{-14} to 10^{-17} over 20 years.

Approximately 100 SMBH sources could be detected with SKA.

Detection prospects improve with future PTA and SKA observations.

Abstract

Context. The early phase of the coalescence of supermassive black hole (SMBH) binaries from their host galaxies provides a guaranteed source of low-frequency (nHz-$\mu$Hz) gravitational wave (GW) radiation by pulsar timing observations. These types of GW sources would survive the coalescing and be potentially identifiable. Aims. We aim to provide an outline of a new method for detecting GW radiation from individual SMBH systems based on the Sloan Digital Sky Survey (SDSS) observational results, which can be verified by future observations. Methods. Combining the sensitivity of the international Pulsar Timing Array (PTA) and the Square Kilometer Array (SKA) detectors, we used a binary population synthesis (BPS) approach to determine GW radiation from close galaxy pairs under the assumption that SMBHs formed at the core of merged galaxies. We also performed second post-Newtonian approximation methods to estimate the variation of the strain amplitude with time. Results. We find that the value of the strain amplitude \emph{h} varies from about $10^{-14}$ to $10^{-17}$ using the observations of 20 years, and we estimate that about 100 SMBH sources can be detected with the SKA detector.