Exploring the Orbital Alignments of Galactic Close White Dwarf Binaries with LISA

TL;DR

This paper discusses how LISA can measure the orientations of thousands of white dwarf binaries in our Galaxy, enabling the study of their orbital alignment patterns and revealing potential fossil records of galactic history.

Contribution

It proposes a method to analyze the orbital orientations of white dwarf binaries using LISA data, highlighting the potential to detect non-random alignment patterns.

Findings

A quadrupole pattern as small as 0.05 can be detected in bulge white dwarf binaries.

LISA's measurements will enable exploration of the Galaxy's ancient orbital configurations.

The study links binary orientations to galactic fossil records.

Abstract

Using the proposed space gravitational wave detector LISA, we will be able to measure the geometrical configurations of $\sim 10^4$ close white dwarf binaries in our Galaxy. The obtained data will be an entirely new resource to examine the randomness of their orbital orientations. Partly motivated by a recent reported on the systematic alignments of bulge planetary nebulae, we discuss the outlook of the orientational analysis with LISA. We find that a quadrupole pattern as small as $\sim 0.05$ can be detected for bulge white dwarf binaries, owing to their large available number. From such a pattern analysis, we might geometrically explore fossil records in our Galaxy billions of years ago.