activity
20242026
most citedGravitational lensing inside and outside of a marginally unstable photon sphere in a general, static, spherically symmetric, and asymptotically-flat spacetime in strong deflection limits

2 citations · 2 across the 1 of their papers we have counts for

collaborators

5 papers

gr-qc20262 cited

Gravitational lensing inside and outside of a marginally unstable photon sphere in a general, static, spherically symmetric, and asymptotically-flat spacetime in strong deflection limits

Naoki Tsukamoto

It is believed that rays bent inside and outside photon spheres could affect partially the black hole shadow images by the Event Horizon Telescope and the rays near photon spheres…

gr-qc2026

Dyonic hairy black holes in gauge-invariant scalar-vector-tensor theories: Cubic and quartic interactions

Masaki Kitagawa, Naoki Tsukamoto, Ryotaro Kase

We construct and classify asymptotically flat, static, spherically symmetric hairy black hole solutions in gauge-invariant scalar-vector-tensor (SVT) theories carrying both…

gr-qc2025

Linear perturbations of dyonic black holes in the lowest-order gauge-invariant scalar-vector-tensor theories

Kitaro Taniguchi, Shunta Nishimura, Naoki Tsukamoto +1

We study linear perturbations on top of the static and spherically symmetric background of dyonic black hole solutions endowed with electric and magnetic charges, as well as a scal…

gr-qc2025

Circular light orbits of a general, static, and spherical symmetrical wormhole with symmetry

Naoki Tsukamoto

Recently, the ring images or the shadow images of the centers of the galaxy M87 and the Milky way have been reported by Event Horizon Telescope Collaboration. It is believed that t…

gr-qc2024

Neutral particle collisions near Gibbons-Maeda-Garfinkle-Horowitz-Strominger black holes after shadow observations

Naoki Tsukamoto, Ryotaro Kase

A Gibbons-Maeda-Garfinkle-Horowitz-Strominger (GMGHS) black hole with a magnetic charge (or an electric charge) has noteworthy features that its scalar curvature near the event hor…