Binary-pulsar Timing: A 3D Solar-System Accelerometer and Unknown-Source Probe
Abstract
The acceleration of the Solar System barycenter (SSB) offers a unique precision probe of the local gravitational environment, enabling searches for otherwise invisible gravitating sources such as Planet Nine and nearby (primordial) black holes. Using the binary-pulsar timing measurements, we develop an analysis framework that combines the line-of-sight differential accelerations of 26 binary pulsars to jointly reconstruct the three-dimensional acceleration of the SSB and place directional upper limits. Across three smooth Galactic-potential baselines, the residual acceleration is consistent with zero. We obtain directional 95\% upper limits of $0.198$, $0.262$, and 0.693 μas yr−1 over 50\%, 75\%, and all sampled directions, respectively. These limits are tighter by factors of 3.5, 3.6, and 1.6 than a matched Gaia EDR3 benchmark and improve previous pulsar constraints by more than an order of magnitude. We further extend the framework to the full SSB--pulsar two-endpoint response, enabling direct position-dependent mass constraints on unknown gravitational sources. A 10 M⊙ object is excluded within 0.39, 0.34, and 0.21 pc over the same sky fractions. Our unknown-mass limits surpass the tidal-equivalent INPOP19a reference beyond 0.2 pc by about an order of magnitude over most of the sky at 1 pc.
Related
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- Hierarchical Inference of the Supermassive Black Hole Binary Merger Rates from Joint Searches using Pulsar Timing Arrays
- High precision timing of seven binary millisecond pulsars with the European Pulsar Timing Array
- Red noise and evolving signals: a complete frequentist approach to supermassive black hole binary searches with pulsar timing arrays
BibTeX
@misc{wang2026binarypulsar,
title = {{Binary-pulsar Timing: A 3D Solar-System Accelerometer and Unknown-Source Probe}},
author = {Zheng-Long Wang and Zi-Qing Xia and Bo Zhang and Yi-Zhong Fan},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.29162},
eprint = {2609.29162},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.29162},
}
RIS
TY - UNPB
TI - Binary-pulsar Timing: A 3D Solar-System Accelerometer and Unknown-Source Probe
AU - Zheng-Long Wang
AU - Zi-Qing Xia
AU - Bo Zhang
AU - Yi-Zhong Fan
PY - 2026
DA - 2026/09/24
PB - arXiv
DO - 10.48550/arxiv.2609.29162
UR - https://arxiv.org/abs/2609.29162
AB - The acceleration of the Solar System barycenter (SSB) offers a unique precision probe of the local gravitational environment, enabling searches for otherwise invisible gravitating sources such as Planet Nine and nearby (primordial) black holes. Using the binary-pulsar timing measurements, we develop an analysis framework that combines the line-of-sight differential accelerations of 26 binary pulsars to jointly reconstruct the three-dimensional acceleration of the SSB and place directional upper limits. Across three smooth Galactic-potential baselines, the residual acceleration is consistent with zero. We obtain directional 95\% upper limits of $0.198$, $0.262$, and 0.693 μas yr^−1 over 50\%, 75\%, and all sampled directions, respectively. These limits are tighter by factors of 3.5, 3.6, and 1.6 than a matched Gaia EDR3 benchmark and improve previous pulsar constraints by more than an order of magnitude. We further extend the framework to the full SSB--pulsar two-endpoint response, enabling direct position-dependent mass constraints on unknown gravitational sources. A 10 M_⊙ object is excluded within 0.39, 0.34, and 0.21 pc over the same sky fractions. Our unknown-mass limits surpass the tidal-equivalent INPOP19a reference beyond 0.2 pc by about an order of magnitude over most of the sky at 1 pc.
ER -