# Presaging Doppler beaming discoveries of double white dwarfs during the Rubin LSST era

**Authors:** Gautham Adamane Pallathadka, Yossef Zenati, Nadia L. Zakamska, Ngan H. Nguyen, Anthony L. Piro  
**arXiv:** [2602.13137](https://arxiv.org/abs/2602.13137)  
**Date:** 2026-02-13  
**Summary page:** https://www.summarizepaper.com/en/arxiv-id/2602.13137v1/

## Key points

- Double white dwarfs (DWDs) are prevalent compact binaries in the Milky Way
- DWDs serve as crucial low-frequency gravitational-wave sources and potential progenitors of Type Ia supernovae
- A comprehensive binary population synthesis was conducted using SeBa to study DWDs
- The Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) is capable of detecting bright unequal-mass binaries in compact orbits with periods ranging from 10 to 600 minutes
- LSST is projected to identify at least 287 short-period DWDs, including 47 LISA-detectable gravitational wave sources

## Summary

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Double white dwarfs (DWDs) are prevalent compact binaries in the Milky Way, serving as crucial low-frequency gravitational-wave sources and potential progenitors of Type Ia supernovae. Despite their significance, no DWD has been exclusively identified through relativistic Doppler beaming, despite its direct correlation with radial velocity semi-amplitude. To address this gap, a comprehensive binary population synthesis was conducted using SeBa, integrating the resulting binaries into a tripartite Galaxy model. The study's proof-of-concept simulations showcased the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) as capable of reliably detecting relatively bright ($r \lesssim20~$mag) unequal-mass binaries in compact orbits with periods ranging from 10 to 600 minutes and moderate to high inclinations. The LSST is projected to identify at least 287 short-period DWDs, including 47 LISA-detectable gravitational wave sources. Notably, LSST lightcurves enable precise determination of period and full orbit characterization, contrasting with challenges faced in spectroscopic searches for DWDs. The formation of unequal mass, short-period DWDs heavily relies on assumptions regarding mass-transfer phases during binary population synthesis. The total number and characteristics of Doppler-beamed DWD systems observed by LSST will offer valuable insights into models of stellar binary evolution. This study lays the groundwork for seamlessly integrating synthetic Galactic binary populations into realistic LSST survey simulations. Such integration facilitates quantitative forecasts regarding the number and attributes of any binary sub-population throughout the LSST era. Furthermore, advanced techniques such as the accelerated Lomb-Scargle periodogram implemented by NIFTy in astropy were utilized to determine the best-fit period within a typical range expected for photometric variation in WDs (10 minutes to 50 hours). The variability in Doppler beaming amplitude across different bands was also considered. Overall, this research not only sheds light on the detection capabilities of LSST for DWDs but also underscores the importance of refining models for stellar binary evolution based on observational data from upcoming surveys like LSST.