497 citations · 775 across the 20 of their papers we have counts for
20 papers
Strong deflection of massive particles via the geodesic deviation equation
Takahisa Igata, Yohsuke Takamori
We develop a formulation of the strong deflection limit for the scattering of particles following timelike geodesics in asymptotically flat, static, and spherically symmetric space…
Gravitational lensing and accretion disk imaging of a Buchdahl dense core
Takahisa Igata, Motoki Omamiuda, Yohsuke Takamori
In this paper, we investigate the gravitational lensing and accretion disk imaging characteristics of a dense core modeled by the Buchdahl spacetime. By imposing the appropriate en…
Parametrized-Post-Newtonian Test of Black Hole Spacetime for Galactic Center Massive Black Hole Sgr A*: Formulation and Fitting
Hiromi Saida, Sena A. Matsui, Tsutomu T. Takeuchi +4
We have performed a parametrized post-Newtonian (PPN) test of a black hole spacetime using observational data of the star S0-2/S2 orbiting the massive black hole at our galactic ce…
Origin of an Orbiting Star Around the Galactic Supermassive Black Hole
Shogo Nishiyama, Tomohiro Kara, Brian Thorsbro +6
The tremendous tidal force that is linked to the supermassive black hole (SMBH) at the center of our galaxy is expected to strongly subdue star formation in its vicinity. Stars wit…
General formulae for the periapsis shift of a quasi-circular orbit in static spherically symmetric spacetimes and the active gravitational mass density
Tomohiro Harada, Takahisa Igata, Hiromi Saida +1
We study the periapsis shift of a quasi-circular orbit in general static spherically symmetric spacetimes. We derive two formulae in full order with respect to the gravitational fi…
Periapsis shifts in dark matter distribution with a dense core
Takahisa Igata, Yohsuke Takamori
We consider the periapsis shifts in dark matter distribution with a dense core. We model the dark matter distribution as an isotropic gas sphere, the Emden polytropic sphere of ind…