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arXiv · 2508.09931

Fundamental Physics with Pulsars around Sagittarius A$^\star$

Lijing Shao·Zexin Hu
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Abstract

Searching for radio pulsars orbiting around the Galactic centre black hole (BH), Sagittarius A$^\star$ (Sgr A$^\star$), represents a holy grail goal for large-area radio telescopes, in particular for the Square Kilometre Array. Follow-up timing observation of such a PSR-Sgr A$^\star$ binary system with an orbital period $\lesssim O(1\,{\rm year})$ will bring forward a handful of new tests on different aspects of fundamental physics that are barely accessible with other means. However, mass perturbation in the Galactic centre harms the gravitational cleanness of PSR-Sgr A$^\star$ systems. In order to flexibly account for perturbations, a numerical pulsar timing model is gradually being built, which can be used to probe the spacetime around Sgr A$^\star$ BH and study the nature of dark matter.

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Lijing Shao, Zexin Hu. 2025-08-13. Fundamental Physics with Pulsars around Sagittarius A$^\star$. https://doi.org/10.1088/1742-6596%2F3177%2F1%2F012043

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