8 papers
New Universal Relations for Magnetized Neutron Stars
Byon N. Jayawiguna, Siddarth Ajith, Takuya Katagiri +2
Unlike the neutron-star mass--radius relation, which depends sensitively on the internal stellar structure through the equation of state of dense nuclear matter, certain neutron-st…
Out-of-Equilibrium Effects in Non-Radial Relativistic Stellar Perturbations: A Model-Agnostic Formulation and Mode Analysis
Takuya Katagiri, Victor Guedes, Kent Yagi
We present a systematic, model-agnostic analysis of out-of-equilibrium effects, including viscosity and thermal conductivity, in non-radial oscillations of relativistic stars. Exte…
Dynamical Tidal Response of Neutron Stars: from Effective Field Theory to Gravitational Waveforms
Thomas Apostolidis, Valerio De Luca, Leonardo Gualtieri +3
We investigate the fully relativistic dynamical tidal response of neutron stars up to second order in the frequency. Combining the worldline effective field theory for extended gra…
The relativistic restricted three-body problem: geometry and motion around tidally perturbed black holes
Takuya Katagiri, Vitor Cardoso
We investigate the geometry of a tidally deformed, rotating black hole and timelike geodesics in its vicinity. Our framework provides a local picture of the structural evolution of…
Theoretical modeling of approximate universality of tidally deformed neutron stars
Takuya Katagiri, Gowtham Rishi Mukkamala, Kent Yagi
Quasi-universal relations are known to exist among various neutron star observables that do not depend sensitively on the underlying nuclear matter equations of state. For example,…
Stability of relativistic tidal response against small potential modification
Takuya Katagiri, Hiroyuki Nakano, Kazuyuki Omukai
The tidal response of compact objects in an inspiraling binary system is measured by a set of tidal Love and dissipation numbers imprinted in the gravitational waveforms. While a f…