I’m a postdoctoral researcher in the Computational Relativistic Astrophysics group led by Masaru Shibata at the Albert Einstein Institute, Potsdam, working on neutron-star physics and strong-field tests of gravity. See the research, publications, and links pages for more.

Recent work


New · 2026

Convective stability of massive neutron stars formed in binary mergers

Y. Gao, K. Hayashi, K. Kiuchi, A. T.-L. Lam, H.-J. Kuan, M. Shibata — Phys. Rev. D 113, 023011 (2026)

We run fully general-relativistic hydrodynamics simulations of binary neutron-star mergers out to 100 ms post-merger and derive — then apply for the first time — convective-stability criteria for hot, differentially rotating relativistic stars that include both buoyancy and rotation. The remnant massive neutron stars show no large-scale convective instability: entropy and angular momentum both increase outward, and rotation stabilizes regions that the Schwarzschild criterion would call unstable. Mode analysis reveals no observable inertial modes after the quadrupolar f-modes damp, while the persistent m=1 one-armed mode correlates strongly with violations of linear-momentum conservation — suggesting it may be numerical rather than physical.

Recent · 2025

Nonradial oscillations of stratified neutron stars with solid crusts

Y. Gao, H.-J. Kuan, C.-J. Xia, H. O. Silva, M. Shibata — Phys. Rev. D 112, 123006 (2025)

We model the dynamical tide of an inspiraling neutron star as a set of driven harmonic oscillators whose natural frequencies are the quasinormal modes of a fully relativistic stellar model with a solid crust and compositional stratification. Stratification erases the canonical crust–core interface mode and replaces it with compositional gravity modes anchored in outer-core buoyancy; meanwhile, the f-mode and core g-mode can leak into the crust under a penetration criterion we derive. The headline result for multimessenger observations: both resonant g-mode forcing and nonresonant f- and crustal-shear-mode driving can overstress the crust before merger, potentially channeling energy into the magnetosphere and powering electromagnetic precursors.

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