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arXiv · 2503.19512

Conditional Autoencoder for Generating Binary Neutron Star Waveforms with Tidal and Precession Effects

Mengfei Sun·Jie Wu·Jin Li·Brendan Mccane·Nan Yang·Xianghe Ma·Borui Wang·Minghui Zhang
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Abstract

Gravitational waves from binary neutron star mergers provide critical insights into dense matter physics and strong-field gravity, yet accurate waveform modeling remains computationally intensive. We present a deep generative model for gravitational waveforms from binary neutron star mergers that captures the late inspiral, merger, and ringdown phases while incorporating spin precession and tidal effects. Using a conditional autoencoder architecture, the model efficiently produces high-fidelity waveforms across a broad parameter space, including component masses (m1, m2), spin components (S1x, S1y, S1z, S2x, S2y, S2z), and tidal deformabilities (Lambda1, Lambda2). Trained on 1*10^6 waveforms generated by the IMRPhenomXP_NRTidalv2 model, our network achieves a mean mismatch of 2.13*10^-3. The generation time for a single waveform is 0.12 s, compared to 0.66 s for IMRPhenomXP_NRTidalv2, representing a speedup of about fivefold. When generating 1000 waveforms, the model completes the task in 0.75 s, roughly ten times faster than the baseline. This significant acceleration facilitates rapid parameter estimation and real-time gravitational-wave searches. With improved precision and efficiency, the model can support low-latency detection and broader applications in multi-messenger astrophysics.

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Mengfei Sun, Jie Wu, Jin Li, Brendan Mccane, Nan Yang, Xianghe Ma, Borui Wang, Minghui Zhang. 2025-03-25. Conditional Autoencoder for Generating Binary Neutron Star Waveforms with Tidal and Precession Effects. https://doi.org/10.1103/kmlw-y7yw

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