# Extracting Astrophysical Information of Highly-Eccentric Binaries in the Millihertz Gravitational Wave Band

**Authors:** Zeyuan Xuan, Smadar Naoz, Alvin K. Y. Li, Bence Kocsis, Erik Petigura, Alan M. Knee, Jess McIver, Kyle Kremer, Will M. Farr  
**arXiv:** [2409.15413](https://arxiv.org/abs/2409.15413)  
**Date:** 2024-09-23  
**Summary page:** https://www.summarizepaper.com/en/paper/2409.15413v2/

## Key points

- Study focuses on wide and highly eccentric compact binaries as potential progenitors of gravitational wave (GW) mergers
- Highly eccentric systems in millihertz (mHz) band emit distinctive GW signals characterized by "repeated bursts" during pericenter passages
- Detection of mHz GW signals can significantly constrain orbital parameters with high precision: relative measurement error of approximately $10^{-6}$ for orbital frequency and around 1% for eccentricity
- Parameters like mass ratio, distance, and intrinsic orbital inclination may have less precise determination due to degeneracies in the GW waveform
- Mock LISA data analysis shows efficient identification of highly eccentric systems under conditions with multiple GW sources and Gaussian noise
- Extracting signals from "bursting" LISA sources provides valuable insights into orbital evolution, surrounding environment, and formation channels of these systems

## Summary

In their study titled "Extracting Astrophysical Information of Highly-Eccentric Binaries in the Millihertz Gravitational Wave Band," authors Zeyuan Xuan, Smadar Naoz, Alvin K. Y. Li, Bence Kocsis, Erik Petigura, Alan M. Knee, Jess McIver, Kyle Kremer, and Will M. Farr delve into the exploration of wide and highly eccentric compact binaries as potential progenitors of gravitational wave (GW) mergers. These systems are anticipated to be prevalent in the millihertz (mHz) band and exhibit distinctive GW signals characterized by "repeated bursts" emitted during each pericenter passage. The researchers demonstrate that detecting mHz GW signals from highly eccentric stellar mass binaries within the local universe can significantly constrain their orbital parameters with remarkable precision. Specifically, they achieve a relative measurement error of approximately $10^{-6}$ for orbital frequency and around 1% for eccentricity (as $1-e$) in most detectable cases. However, parameters such as the binary's mass ratio, distance, and intrinsic orbital inclination may be subject to less precise determination due to degeneracies present in the GW waveform. To evaluate the realistic detectability of highly eccentric compact binaries, the team conducts mock LISA data analysis under conditions where multiple GW sources and stationary Gaussian instrumental noise are present in the detector output. Their findings indicate that highly eccentric systems can be efficiently identified under such circumstances. This research underscores the potential significance of extracting signals from "bursting" LISA sources as a means to gain valuable insights into various aspects of these systems including their orbital evolution, surrounding environment, and formation channels. The comprehensive analysis presented by Xuan et al. sheds light on the astrophysical implications of highly eccentric binaries in the millihertz gravitational wave band and highlights avenues for further exploration in this intriguing field of study.