Exploring Temperature Influences on Gravitational Wave Production in Binary White Dwarfs

TL;DR

This paper examines how temperature affects gravitational wave emission from merging hot white dwarfs, finding that higher temperatures reduce GW signals while more massive stars produce stronger, more detectable waves.

Contribution

It introduces calculations of tidal deformability and GW characteristics for hot white dwarfs, highlighting the impact of temperature and mass on GW detectability with LISA.

Findings

Higher central temperatures increase tidal deformability

More massive white dwarfs emit stronger GWs

High-mass binaries have frequencies within LISA's detection range

Abstract

This study investigates the conditions under which gravitational waves (GWs) are emitted during the merger of hot white dwarfs (WDs) in a binary system. Traditionally, these systems consist of two low-mass stars or a more massive WD paired with a less massive companion. In addition, recent work has investigated the possibility that double white dwarf (DWD) mergers are possibly the leading formation channel of massive, rapidly rotating, high-field magnetic WDs , particularly SDSS J221141.80 + 113604.4 (hereafter J2211+1136) and ZTF J190132.9 + 145808.7 (hereafter J1901 + 14588). Motivated by these findings and the Laser Interferometer Space Antenna (LISA) prospects, this study aims to calculate the tidal Love number, the dimensionless tidal deformability, as well as the frequency and amplitude of GWs of hot WDs. The results indicate that the tidal deformability is more pronounced in stars with higher central temperatures and lower masses, which would lead to reduced emission of GWs. In contrast, more massive stars exhibit less deformability, making them prime candidates for generating stronger GWs. Additionally, the analysis of frequency and amplitude reveals that the frequencies of high-mass binaries are smaller and evolve more rapidly, reaching a limit that aligns with the operational detection capabilities of LISA during its initial phase.