36 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Kobe UniversityJP4 papers
- Hokkaido UniversityJP3 papers
- National Institute of Technology, Oita CollegeJP3 papers
- The University of TokyoJP3 papers
- Harish-Chandra Research InstituteIN2 papers
- National Astronomical Observatory of JapanJP2 papers
- RIKENJP2 papers
- Aichi University of EducationJP1 paper
- Institute of Space and Astronautical ScienceJP1 paper
- Japan Aerospace Exploration AgencyJP1 paper
- Kavli Institute for the Physics and Mathematics of the UniverseJP1 paper
- Korea Institute for Advanced StudyKR1 paper
18 papers
A relativistic two-stream instability in an extremely low-density plasma
Shinji Koide, Masaaki Takahashi, Rohta Takahashi
A linear analysis based on two-fluid equations in the approximation of a cold plasma, wherein the plasma temperature is assumed to be zero, demonstrates that a two-stream instabili…
3D Photon Conserving Code for Time-dependent General Relativistic Radiative Transfer : CARTOON
Mikiya M. Takahashi, Ken Ohsuga, Rohta Takahashi +3
We develop the 3-dimensional general relativistic radiative transfer code: CARTOON (Calculation code of Authentic Radiative Transfer based On phOton Number conservation in curved s…
Correspondence of topological classification between quantum graph extra dimension and topological matter
Tomonori Inoue, Makoto Sakamoto, Masatoshi Sato +1
In this paper, we study five-dimensional Dirac fermions of which extra-dimension is compactified on quantum graphs. We find that there is a non-trivial correspondence between matri…
Relativistic Rational Extended Thermodynamics of Polyatomic Gases with a New Hierarchy of Moments
Takashi Arima, Maria Cristina Carrisi, Sebastiano Pennisi +1
A relativistic version of the rational extended thermodynamics of polyatomic gases based on a new hierarchy of moments that takes into account the total energy composed by the rest…
Peculiarity of Symmetric Ring Systems with Double Y-Junctions and the magnetic effects
Yukihiro Fujimoto, Kohkichi Konno, Tomoaki Nagasawa
We discuss quantum dynamics in the ring systems with double Y-junctions in which two arms have same length. The node of a Y-junction can be parametrized by U(3). Considering mathem…
Quantum Reflection and Transmission in Ring Systems with Double Y-Junctions: Occurrence of Perfect Reflection
Yukihiro Fujimoto, Kohkichi Konno, Tomoaki Nagasawa +1
We consider the scattering problems of a quantum particle in a system with a single Y-junction and in ring systems with double Y-junctions. We provide new formalism for such quantu…
Resonant Transmission in One-Dimensional Quantum Mechanics with Two Independent Point Interactions: Full Parameter Analysis
Kohkichi Konno, Tomoaki Nagasawa, Rohta Takahashi
We discuss the scattering of a quantum particle by two independent successive point interactions in one dimension. The parameter space for two point interactions is given by $U(2)\…
Effects of Two Successive Parity-Invariant Point Interactions on One-Dimensional Quantum Transmission: Resonance Conditions for the Parameter Space
Kohkichi Konno, Tomoaki Nagasawa, Rohta Takahashi
We consider the scattering of a quantum particle by two independent, successive parity-invariant point interactions in one dimension. The parameter space for the two point interact…
Active Dirac Neutrinos via Doublets in 5d
Yukihiro Fujimoto, K. Hasegawa, Tomoaki Nagasawa +3
We propose a new mechanism to generate minuscule active neutrino masses in a five-dimensional~(5d) spacetime of an interval without introducing singlet neutrinos. Under a…
Scalar field excited around a rapidly rotating black hole in Chern-Simons modified gravity
Kohkichi Konno, Rohta Takahashi
We discuss a Chern-Simons (CS) scalar field around a rapidly rotating black hole in dynamical CS modified gravity. The CS correction can be obtained perturbatively by considering t…
Multi-Epoch VERA Observations of Sagittarius A*: I. Images and Structural Variability
Kazunori Akiyama, Rohta Takahashi, Mareki Honma +2
We report the results of multi-epoch observations of Sgr A* with VLBI Exploration of Radio Astrometry (VERA) at 43 GHz, carried out from 2004 to 2008. We detected a time variation…
Counter effects of meridional flows and magnetic fields in stationary axisymmetric self-gravitating barotropes under the ideal MHD approximation: clear examples - toroidal configurations
Kotaro Fujisawa, Rohta Takahashi, Shijun Yoshida +1
We obtain the general forms for the current density and the vorticity from the integrability conditions of the basic equations which govern the stationary states of axisymmetric ma…
Spectroscopy along Multiple, Lensed Sightlines through Outflowing Winds in the Quasar SDSS J1029+2623
Toru Misawa, Naohisa Inada, Ken Ohsuga +3
We study the origin of absorption features on the blue side of the C IV broad emission line of the large-separation lensed quasar SDSS J1029+2623 at z_em ~ 2.197. The quasar images…
Quark mass hierarchy and mixing via geometry of extra dimension with point interactions
Yukihiro Fujimoto, Tomoaki Nagasawa, Kenji Nishiwaki +1
We propose a new model which can naturally explain origins of fermion generations, quark mass hierarchy, and Cabibbo-Kobayashi-Maskawa matrix simultaneously from geometry of an ext…
Spacetime rotation-induced Landau quantization
Kohkichi Konno, Rohta Takahashi
We investigate non-inertial and gravitational effects on quantum states in electromagnetic fields and present the analytic solution for energy eigenstates for the Schrödinger equat…
Phase Structure of Gauge Theories on an Interval
Yukihiro Fujimoto, Tomoaki Nagasawa, Satoshi Ohya +1
We discuss gauge symmetry breaking in a general framework of gauge theories on an interval. We first derive a possible set of boundary conditions for a scalar field, which are comp…
Emergent Supersymmetry in Warped Backgrounds
Tomoaki Nagasawa, Satoshi Ohya, Kazuki Sakamoto +1
We show that quantum mechanical supersymmetries are emerged in Kaluza-Klein spectrum of linearized gravity in several warped backgrounds as a consequence of higher-dimensional gene…
Effects of Chern-Simons Corrections on Conserved Quantities of Relativistic Fluid
Kohkichi Konno, Toyoki Matsuyama, Satoshi Tanda
We consider relativistic fluid flow under Chern-Simons modified Maxwell theory and under Chern-Simons modified gravity theory. We take account of the effects of Chern-Simons correc…