Searching for gravitational wave echo with group equivariant neural posterior estimation

Jian-Wei Luo; Yun-Song Piao

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arXiv · 2609.18337

Searching for gravitational wave echo with group equivariant neural posterior estimation

Jian-Wei Luo·Yun-Song Piao

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Abstract

Current methods for the gravitational-wave (GW) echo searches generally require substantial computational time and resources. Recent advances in group equivariant neural posterior estimation (GNPE) have demonstrated the potential to substantially accelerate posterior inference. In this work, we adopt this framework and train a GNPE model to perform echo searches, significantly improving computational efficiency while maintaining comparable inference accuracy. We apply it to the O4a events and find no significant evidence for the GW echo.

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Jian-Wei Luo, Yun-Song Piao. 2026-09-16. Searching for gravitational wave echo with group equivariant neural posterior estimation. https://arxiv.org/abs/2609.18337

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